Linus pointed out that there were locations that did the hard coded
update of the parent and rip parameters. One of them was the static tracer
which could also use the ftrace_caller_setup to do that work. In fact,
because it did not use it, it is prone to bugs, and since the static
tracer is hardly ever used (who wants function tracing code always being
called?) it doesn't get tested very often. I only run a few "does it still
work" tests on it. But I do not run stress tests on that code. Although,
since it is never turned off, just having it on should be stressful enough.
(especially for the performance folks)
There's no reason that the static tracer can't also use ftrace_caller_setup.
Have it do so.
Link: http://lkml.kernel.org/r/CA+55aFwF+qCGSKdGaEgW4p6N65GZ5_XTV=1NbtWDvxnd5yYLiw@mail.gmail.com
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1411262304010.3961@nanos
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Hand down the cpu number instead, otherwise lockdep screams when doing
echo 1 > /sys/devices/system/cpu/microcode/reload.
BUG: using smp_processor_id() in preemptible [00000000] code: amd64-microcode/2470
caller is debug_smp_processor_id+0x12/0x20
CPU: 1 PID: 2470 Comm: amd64-microcode Not tainted 3.18.0-rc6+ #26
...
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1417428741-4501-1-git-send-email-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
First, there was this: https://bugzilla.kernel.org/show_bug.cgi?id=88001
The problem there was that microcode patches are not being reapplied
after suspend-to-ram. It was important to reapply them, though, because
of for example Haswell's TSX erratum which disabled TSX instructions
with a microcode patch.
A simple fix was fb86b97300 ("x86, microcode: Update BSPs microcode
on resume") but, as it is often the case, simple fixes are too
simple. This one causes 32-bit resume to fail:
https://bugzilla.kernel.org/show_bug.cgi?id=88391
Properly fixing this would require more involved changes for which it
is too late now, right before the merge window. Thus, limit this to
64-bit only temporarily.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1417353999-32236-1-git-send-email-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This reverts commit 85c8555ff0 ("KVM: check for !is_zero_pfn() in
kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn.
The problem being addressed by the patch above was that some ARM code
based the memory mapping attributes of a pfn on the return value of
kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should
be mapped as device memory.
However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin,
and the existing non-ARM users were already using it in a way which
suggests that its name should probably have been 'kvm_is_reserved_pfn'
from the beginning, e.g., whether or not to call get_page/put_page on
it etc. This means that returning false for the zero page is a mistake
and the patch above should be reverted.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This adds the module loading prefix "crypto-" to the template lookup
as well.
For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":
net-pf-38
algif-hash
crypto-vfat(blowfish)
crypto-vfat(blowfish)-all
crypto-vfat
Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This can't be NULL and we dereferenced it earlier. Smatch used to
ignore these things where the pointer was obviously non-NULL but I've
found that sometimes the intention was to check something else so we
were maybe missing bugs.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This reverts commit 85c8555ff0 ("KVM: check for !is_zero_pfn() in
kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn.
The problem being addressed by the patch above was that some ARM code
based the memory mapping attributes of a pfn on the return value of
kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should
be mapped as device memory.
However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin,
and the existing non-ARM users were already using it in a way which
suggests that its name should probably have been 'kvm_is_reserved_pfn'
from the beginning, e.g., whether or not to call get_page/put_page on
it etc. This means that returning false for the zero page is a mistake
and the patch above should be reverted.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
These functions can be executed on the int3 stack, so kprobes
are dangerous. Tracing is probably a bad idea, too.
Fixes: b645af2d59 ("x86_64, traps: Rework bad_iret")
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: <stable@vger.kernel.org> # Backport as far back as it would apply
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/50e33d26adca60816f3ba968875801652507d0c4.1416870125.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
New updates to the ftrace generic code had ftrace_stub not always being
called when ftrace is off. This causes the static tracer to always save
and restore functions. But it also showed that when function tracing is
running, the function graph tracer can not. We should always check to see
if function graph tracing is running even if the function tracer is running
too. The function tracer code is not the only one that uses the hook to
function mcount.
Cc: Markos Chandras <Markos.Chandras@imgtec.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
cs.base is declared as a __u64 variable and vector is a u32 so this
causes a static checker warning. The user indeed can set "sipi_vector"
to any u32 value in kvm_vcpu_ioctl_x86_set_vcpu_events(), but the
value should really have 8-bit precision only.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Create a new header, and hide the device assignment functions there.
Move struct kvm_assigned_dev_kernel to assigned-dev.c by modifying
arch/x86/kvm/iommu.c to take a PCI device struct.
Based on a patch by Radim Krcmar <rkrcmark@redhat.com>.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:
https://lkml.org/lkml/2013/3/4/70
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but
not on non-paranoid returns. I suspect that this is a mistake and that
the code only works because int3 is paranoid.
Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround
for the x86 bug. With that bug fixed, we can remove _TIF_NOTIFY_RESUME
from the uprobes code.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge x86-64 iret fixes from Andy Lutomirski:
"This addresses the following issues:
- an unrecoverable double-fault triggerable with modify_ldt.
- invalid stack usage in espfix64 failed IRET recovery from IST
context.
- invalid stack usage in non-espfix64 failed IRET recovery from IST
context.
It also makes a good but IMO scary change: non-espfix64 failed IRET
will now report the correct error. Hopefully nothing depended on the
old incorrect behavior, but maybe Wine will get confused in some
obscure corner case"
* emailed patches from Andy Lutomirski <luto@amacapital.net>:
x86_64, traps: Rework bad_iret
x86_64, traps: Stop using IST for #SS
x86_64, traps: Fix the espfix64 #DF fixup and rewrite it in C
It's possible for iretq to userspace to fail. This can happen because
of a bad CS, SS, or RIP.
Historically, we've handled it by fixing up an exception from iretq to
land at bad_iret, which pretends that the failed iret frame was really
the hardware part of #GP(0) from userspace. To make this work, there's
an extra fixup to fudge the gs base into a usable state.
This is suboptimal because it loses the original exception. It's also
buggy because there's no guarantee that we were on the kernel stack to
begin with. For example, if the failing iret happened on return from an
NMI, then we'll end up executing general_protection on the NMI stack.
This is bad for several reasons, the most immediate of which is that
general_protection, as a non-paranoid idtentry, will try to deliver
signals and/or schedule from the wrong stack.
This patch throws out bad_iret entirely. As a replacement, it augments
the existing swapgs fudge into a full-blown iret fixup, mostly written
in C. It's should be clearer and more correct.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On a 32-bit kernel, this has no effect, since there are no IST stacks.
On a 64-bit kernel, #SS can only happen in user code, on a failed iret
to user space, a canonical violation on access via RSP or RBP, or a
genuine stack segment violation in 32-bit kernel code. The first two
cases don't need IST, and the latter two cases are unlikely fatal bugs,
and promoting them to double faults would be fine.
This fixes a bug in which the espfix64 code mishandles a stack segment
violation.
This saves 4k of memory per CPU and a tiny bit of code.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's nothing special enough about the espfix64 double fault fixup to
justify writing it in assembly. Move it to C.
This also fixes a bug: if the double fault came from an IST stack, the
old asm code would return to a partially uninitialized stack frame.
Fixes: 3891a04aaf
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit e6023367d7 'x86, kaslr: Prevent .bss from overlaping initrd'
broke the cross compile of x86. It added a objdump invocation, which
invokes the host native objdump and ignores an active cross tool
chain.
Use $(OBJDUMP) instead which takes the CROSS_COMPILE prefix into
account.
[ tglx: Massage changelog and use $(OBJDUMP) ]
Fixes: e6023367d7 'x86, kaslr: Prevent .bss from overlaping initrd'
Signed-off-by: Chris Clayton <chris2553@googlemail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/54705C8E.1080400@googlemail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This feature is not supported inside KVM guests yet, because we do not emulate
MSR_IA32_XSS. Mask it out.
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that ia64 is gone, we can hide deprecated device assignment in x86.
Notable changes:
- kvm_vm_ioctl_assigned_device() was moved to x86/kvm_arch_vm_ioctl()
The easy parts were removed from generic kvm code, remaining
- kvm_iommu_(un)map_pages() would require new code to be moved
- struct kvm_assigned_dev_kernel depends on struct kvm_irq_ack_notifier
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The PCI/MSI irq chip callbacks mask/unmask_msi_irq have been renamed
to pci_msi_mask/unmask_irq to mark them PCI specific. Rename all usage
sites. The conversion helper functions are kept around to avoid
conflicts in next and will be removed after merging into mainline.
Coccinelle assisted conversion. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: x86@kernel.org
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Murali Karicheri <m-karicheri2@ti.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Mohit Kumar <mohit.kumar@st.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Rename write_msi_msg() to pci_write_msi_msg() to mark it as PCI
specific.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Rename __read_msi_msg() to __pci_read_msi_msg() and kill unused
read_msi_msg(). It's a preparation to separate generic MSI code from
PCI core.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull x86 fixes from Thomas Gleixner:
"Misc fixes:
- gold linker build fix
- noxsave command line parsing fix
- bugfix for NX setup
- microcode resume path bug fix
- _TIF_NOHZ versus TIF_NOHZ bugfix as discussed in the mysterious
lockup thread"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, syscall: Fix _TIF_NOHZ handling in syscall_trace_enter_phase1
x86, kaslr: Handle Gold linker for finding bss/brk
x86, mm: Set NX across entire PMD at boot
x86, microcode: Update BSPs microcode on resume
x86: Require exact match for 'noxsave' command line option
Pull perf fixes from Ingo Molnar:
"Misc fixes: two Intel uncore driver fixes, a CPU-hotplug fix and a
build dependencies fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Fix boot crash on SBOX PMU on Haswell-EP
perf/x86/intel/uncore: Fix IRP uncore register offsets on Haswell EP
perf: Fix corruption of sibling list with hotplug
perf/x86: Fix embarrasing typo
ia64 does not need them anymore. Ack notifiers become x86-specific
too.
Suggested-by: Gleb Natapov <gleb@kernel.org>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
TIF_NOHZ is 19 (i.e. _TIF_SYSCALL_TRACE | _TIF_NOTIFY_RESUME |
_TIF_SINGLESTEP), not (1<<19).
This code is involved in Dave's trinity lockup, but I don't see why
it would cause any of the problems he's seeing, except inadvertently
by causing a different path through entry_64.S's syscall handling.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/a6cd3b60a3f53afb6e1c8081b0ec30ff19003dd7.1416434075.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Recover original IP register if the pre_handler doesn't change it.
Since current kprobes doesn't expect that another ftrace handler
may change regs->ip, it sets kprobe.addr + MCOUNT_INSN_SIZE to
regs->ip and returns to ftrace.
This seems wrong behavior since kprobes can recover regs->ip
and safely pass it to another handler.
This adds code which recovers original regs->ip passed from
ftrace right before returning to ftrace, so that another ftrace
user can change regs->ip.
Link: http://lkml.kernel.org/r/20141009130106.4698.26362.stgit@kbuild-f20.novalocal
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When trigger_all_cpu_backtrace() is called on x86, it will trigger an
NMI on each CPU and call show_regs(). But this can lead to a hard lock
up if the NMI comes in on another printk().
In order to avoid this, when the NMI triggers, it switches the printk
routine for that CPU to call a NMI safe printk function that records the
printk in a per_cpu seq_buf descriptor. After all NMIs have finished
recording its data, the seq_bufs are printed in a safe context.
Link: http://lkml.kernel.org/p/20140619213952.360076309@goodmis.org
Link: http://lkml.kernel.org/r/20141115050605.055232587@goodmis.org
Tested-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
To allow for the restructiong of the trace_seq code, we need users
of it to use the helper functions instead of accessing the internals
of the trace_seq structure itself.
Link: http://lkml.kernel.org/r/20141104160221.585025609@goodmis.org
Tested-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Mark Rustad <mark.d.rustad@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Stack traces that happen from function tracing check if the address
on the stack is a __kernel_text_address(). That is, is the address
kernel code. This calls core_kernel_text() which returns true
if the address is part of the builtin kernel code. It also calls
is_module_text_address() which returns true if the address belongs
to module code.
But what is missing is ftrace dynamically allocated trampolines.
These trampolines are allocated for individual ftrace_ops that
call the ftrace_ops callback functions directly. But if they do a
stack trace, the code checking the stack wont detect them as they
are neither core kernel code nor module address space.
Adding another field to ftrace_ops that also stores the size of
the trampoline assigned to it we can create a new function called
is_ftrace_trampoline() that returns true if the address is a
dynamically allocate ftrace trampoline. Note, it ignores trampolines
that are not dynamically allocated as they will return true with
the core_kernel_text() function.
Link: http://lkml.kernel.org/r/20141119034829.497125839@goodmis.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When CONFIG_FRAME_POINTERS are enabled, it is required that the
ftrace_caller and ftrace_regs_caller trampolines set up frame pointers
otherwise a stack trace from a function call wont print the functions
that called the trampoline. This is due to a check in
__save_stack_address():
#ifdef CONFIG_FRAME_POINTER
if (!reliable)
return;
#endif
The "reliable" variable is only set if the function address is equal to
contents of the address before the address the frame pointer register
points to. If the frame pointer is not set up for the ftrace caller
then this will fail the reliable test. It will miss the function that
called the trampoline. Worse yet, if fentry is used (gcc 4.6 and
beyond), it will also miss the parent, as the fentry is called before
the stack frame is set up. That means the bp frame pointer points
to the stack of just before the parent function was called.
Link: http://lkml.kernel.org/r/20141119034829.355440340@goodmis.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: stable@vger.kernel.org # 3.7+
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Uncorrected no action required (UCNA) - is a uncorrected recoverable
machine check error that is not signaled via a machine check exception
and, instead, is reported to system software as a corrected machine
check error. UCNA errors indicate that some data in the system is
corrupted, but the data has not been consumed and the processor state
is valid and you may continue execution on this processor. UCNA errors
require no action from system software to continue execution. Note that
UCNA errors are supported by the processor only when IA32_MCG_CAP[24]
(MCG_SER_P) is set.
-- Intel SDM Volume 3B
Deferred errors are errors that cannot be corrected by hardware, but
do not cause an immediate interruption in program flow, loss of data
integrity, or corruption of processor state. These errors indicate
that data has been corrupted but not consumed. Hardware writes information
to the status and address registers in the corresponding bank that
identifies the source of the error if deferred errors are enabled for
logging. Deferred errors are not reported via machine check exceptions;
they can be seen by polling the MCi_STATUS registers.
-- AMD64 APM Volume 2
Above two items, both UCNA and Deferred errors belong to detected
errors, but they can't be corrected by hardware, and this is very
similar to Software Recoverable Action Optional (SRAO) errors.
Therefore, we can take some actions that have been used for handling
SRAO errors to handle UCNA and Deferred errors.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Until now, the mce_severity mechanism can only identify the severity
of UCNA error as MCE_KEEP_SEVERITY. Meanwhile, it is not able to filter
out DEFERRED error for AMD platform.
This patch extends the mce_severity mechanism for handling
UCNA/DEFERRED error. In order to do this, the patch introduces a new
severity level - MCE_UCNA/DEFERRED_SEVERITY.
In addition, mce_severity is specific to machine check exception,
and it will check MCIP/EIPV/RIPV bits. In order to use mce_severity
mechanism in non-exception context, the patch also introduces a new
argument (is_excp) for mce_severity. `is_excp' is used to explicitly
specify the calling context of mce_severity.
Reviewed-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Remove FIXME comments about needing fault addresses to be returned. These
are propaagated from walk_addr_generic to gva_to_gpa and from there to
ops->read_std and ops->write_std.
Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The check on the higher limit of the segment, and the check on the
maximum accessible size, is the same for both expand-up and
expand-down segments. Only the computation of "lim" varies.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
register_address has been a duplicate of address_mask ever since the
ancestor of __linearize was born in 90de84f50b (KVM: x86 emulator:
preserve an operand's segment identity, 2010-11-17).
However, we can put it to a better use by including the call to reg_read
in register_address. Similarly, the call to reg_rmw can be moved to
register_address_increment.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In __linearize there is check of the condition whether to check if masking of
the linear address is needed. It occurs immediately after switch that
evaluates the same condition. Merge them.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When SS is used using a non-canonical address, an #SS exception is generated on
real hardware. KVM emulator causes a #GP instead. Fix it to behave as real x86
CPU.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If branch (e.g., jmp, ret) causes limit violations, since the target IP >
limit, the #GP exception occurs before the branch. In other words, the RIP
pushed on the stack should be that of the branch and not that of the target.
To do so, we can call __linearize, with new EIP, which also saves us the code
which performs the canonical address checks. On the case of assigning an EIP >=
2^32 (when switching cs.l), we also safe, as __linearize will check the new EIP
does not exceed the limit and would trigger #GP(0) otherwise.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When segment is accessed, real hardware does not perform any privilege level
checks. In contrast, KVM emulator does. This causes some discrepencies from
real hardware. For instance, reading from readable code segment may fail due to
incorrect segment checks. In addition, it introduces unnecassary overhead.
To reference Intel SDM 5.5 ("Privilege Levels"): "Privilege levels are checked
when the segment selector of a segment descriptor is loaded into a segment
register." The SDM never mentions privilege level checks during memory access,
except for loading far pointers in section 5.10 ("Pointer Validation"). Those
are actually segment selector loads and are emulated in the similarily (i.e.,
regardless to __linearize checks).
This behavior was also checked using sysexit. A data-segment whose DPL=0 was
loaded, and after sysexit (CPL=3) it is still accessible.
Therefore, all the privilege level checks in __linearize are removed.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When performing segmented-read/write in the emulator for stack operations, it
ignores the stack size, and uses the ad_bytes as indication for the pointer
size. As a result, a wrong address may be accessed.
To fix this behavior, we can remove the masking of address in __linearize and
perform it beforehand. It is already done for the operands (so currently it is
inefficiently done twice). It is missing in two cases:
1. When using rip_relative
2. On fetch_bit_operand that changes the address.
This patch masks the address on these two occassions, and removes the masking
from __linearize.
Note that it does not mask EIP during fetch. In protected/legacy mode code
fetch when RIP >= 2^32 should result in #GP and not wrap-around. Since we make
limit checks within __linearize, this is the expected behavior.
Partial revert of commit 518547b32a (KVM: x86: Emulator does not
calculate address correctly, 2014-09-30).
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 10e38fc7cab6 ("KVM: x86: Emulator flag for instruction that only support
16-bit addresses in real mode") introduced NoBigReal for instructions such as
MONITOR. Apparetnly, the Intel SDM description that led to this patch is
misleading. Since no instruction is using NoBigReal, it is safe to remove it,
we fully understand what the SDM means.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
asm-generic/mm_hooks.h provides some generic fillers for the 90%
of architectures that do not need to hook some mmap-manipulation
functions. A comment inside says:
> Define generic no-op hooks for arch_dup_mmap and
> arch_exit_mmap, to be included in asm-FOO/mmu_context.h
> for any arch FOO which doesn't need to hook these.
So, does x86 need to hook these? It depends on CONFIG_PARAVIRT.
We *conditionally* include this generic header if we have
CONFIG_PARAVIRT=n. That's madness.
With this patch, x86 stops using asm-generic/mmu_hooks.h entirely.
We use our own copies of the functions. The paravirt code
provides some stubs if it is disabled, and we always call those
stubs in our x86-private versions of arch_exit_mmap() and
arch_dup_mmap().
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20141118182349.14567FA5@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
get_reg_offset() used to return the register contents themselves
instead of the register offset. When it did that, it was an
unsigned long. I changed it to return an integer _offset_
instead of the register. But, I neglected to change the return
type of the function or the variables in which we store the
result of the call.
This fixes up the code to clear up the warnings from the smatch
bot:
New smatch warnings:
arch/x86/mm/mpx.c:178 mpx_get_addr_ref() warn: unsigned 'addr_offset' is never less than zero.
arch/x86/mm/mpx.c:184 mpx_get_addr_ref() warn: unsigned 'base_offset' is never less than zero.
arch/x86/mm/mpx.c:188 mpx_get_addr_ref() warn: unsigned 'indx_offset' is never less than zero.
arch/x86/mm/mpx.c:196 mpx_get_addr_ref() warn: unsigned 'addr_offset' is never less than zero.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20141118182343.C3E0C629@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When building with the Gold linker, the .bss and .brk areas of vmlinux
are shown as consecutive instead of having the same file offset. Allow
for either state, as long as things add up correctly.
Fixes: e6023367d7 ("x86, kaslr: Prevent .bss from overlaping initrd")
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Link: http://lkml.kernel.org/r/20141118001604.GA25045@www.outflux.net
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When setting up permissions on kernel memory at boot, the end of the
PMD that was split from bss remained executable. It should be NX like
the rest. This performs a PMD alignment instead of a PAGE alignment to
get the correct span of memory.
Before:
---[ High Kernel Mapping ]---
...
0xffffffff8202d000-0xffffffff82200000 1868K RW GLB NX pte
0xffffffff82200000-0xffffffff82c00000 10M RW PSE GLB NX pmd
0xffffffff82c00000-0xffffffff82df5000 2004K RW GLB NX pte
0xffffffff82df5000-0xffffffff82e00000 44K RW GLB x pte
0xffffffff82e00000-0xffffffffc0000000 978M pmd
After:
---[ High Kernel Mapping ]---
...
0xffffffff8202d000-0xffffffff82200000 1868K RW GLB NX pte
0xffffffff82200000-0xffffffff82e00000 12M RW PSE GLB NX pmd
0xffffffff82e00000-0xffffffffc0000000 978M pmd
[ tglx: Changed it to roundup(_brk_end, PMD_SIZE) and added a comment.
We really should unmap the reminder along with the holes
caused by init,initdata etc. but thats a different issue ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20141114194737.GA3091@www.outflux.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In the situation when we apply early microcode but do *not* apply late
microcode, we fail to update the BSP's microcode on resume because we
haven't initialized the uci->mc microcode pointer. So, in order to
alleviate that, we go and dig out the stashed microcode patch during
early boot. It is basically the same thing that is done on the APs early
during boot so do that too here.
Tested-by: alex.schnaidt@gmail.com
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=88001
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: <stable@vger.kernel.org> # v3.9
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20141118094657.GA6635@pd.tnic
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
MMIO_MAX_GEN is the same as MMIO_GEN_MASK. Use only one.
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead, just use PFERR_{FETCH, PRESENT, WRITE}_MASK
inside handle_ept_violation() for slightly better code.
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The previous patch allocates bounds tables on-demand. As noted in
an earlier description, these can add up to *HUGE* amounts of
memory. This has caused OOMs in practice when running tests.
This patch adds support for freeing bounds tables when they are no
longer in use.
There are two types of mappings in play when unmapping tables:
1. The mapping with the actual data, which userspace is
munmap()ing or brk()ing away, etc...
2. The mapping for the bounds table *backing* the data
(is tagged with VM_MPX, see the patch "add MPX specific
mmap interface").
If userspace use the prctl() indroduced earlier in this patchset
to enable the management of bounds tables in kernel, when it
unmaps the first type of mapping with the actual data, the kernel
needs to free the mapping for the bounds table backing the data.
This patch hooks in at the very end of do_unmap() to do so.
We look at the addresses being unmapped and find the bounds
directory entries and tables which cover those addresses. If
an entire table is unused, we clear associated directory entry
and free the table.
Once we unmap the bounds table, we would have a bounds directory
entry pointing at empty address space. That address space might
now be allocated for some other (random) use, and the MPX
hardware might now try to walk it as if it were a bounds table.
That would be bad. So any unmapping of an enture bounds table
has to be accompanied by a corresponding write to the bounds
directory entry to invalidate it. That write to the bounds
directory can fault, which causes the following problem:
Since we are doing the freeing from munmap() (and other paths
like it), we hold mmap_sem for write. If we fault, the page
fault handler will attempt to acquire mmap_sem for read and
we will deadlock. To avoid the deadlock, we pagefault_disable()
when touching the bounds directory entry and use a
get_user_pages() to resolve the fault.
The unmapping of bounds tables happends under vm_munmap(). We
also (indirectly) call vm_munmap() to _do_ the unmapping of the
bounds tables. We avoid unbounded recursion by disallowing
freeing of bounds tables *for* bounds tables. This would not
occur normally, so should not have any practical impact. Being
strict about it here helps ensure that we do not have an
exploitable stack overflow.
Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151831.E4531C4A@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This is really the meat of the MPX patch set. If there is one patch to
review in the entire series, this is the one. There is a new ABI here
and this kernel code also interacts with userspace memory in a
relatively unusual manner. (small FAQ below).
Long Description:
This patch adds two prctl() commands to provide enable or disable the
management of bounds tables in kernel, including on-demand kernel
allocation (See the patch "on-demand kernel allocation of bounds tables")
and cleanup (See the patch "cleanup unused bound tables"). Applications
do not strictly need the kernel to manage bounds tables and we expect
some applications to use MPX without taking advantage of this kernel
support. This means the kernel can not simply infer whether an application
needs bounds table management from the MPX registers. The prctl() is an
explicit signal from userspace.
PR_MPX_ENABLE_MANAGEMENT is meant to be a signal from userspace to
require kernel's help in managing bounds tables.
PR_MPX_DISABLE_MANAGEMENT is the opposite, meaning that userspace don't
want kernel's help any more. With PR_MPX_DISABLE_MANAGEMENT, the kernel
won't allocate and free bounds tables even if the CPU supports MPX.
PR_MPX_ENABLE_MANAGEMENT will fetch the base address of the bounds
directory out of a userspace register (bndcfgu) and then cache it into
a new field (->bd_addr) in the 'mm_struct'. PR_MPX_DISABLE_MANAGEMENT
will set "bd_addr" to an invalid address. Using this scheme, we can
use "bd_addr" to determine whether the management of bounds tables in
kernel is enabled.
Also, the only way to access that bndcfgu register is via an xsaves,
which can be expensive. Caching "bd_addr" like this also helps reduce
the cost of those xsaves when doing table cleanup at munmap() time.
Unfortunately, we can not apply this optimization to #BR fault time
because we need an xsave to get the value of BNDSTATUS.
==== Why does the hardware even have these Bounds Tables? ====
MPX only has 4 hardware registers for storing bounds information.
If MPX-enabled code needs more than these 4 registers, it needs to
spill them somewhere. It has two special instructions for this
which allow the bounds to be moved between the bounds registers
and some new "bounds tables".
They are similar conceptually to a page fault and will be raised by
the MPX hardware during both bounds violations or when the tables
are not present. This patch handles those #BR exceptions for
not-present tables by carving the space out of the normal processes
address space (essentially calling the new mmap() interface indroduced
earlier in this patch set.) and then pointing the bounds-directory
over to it.
The tables *need* to be accessed and controlled by userspace because
the instructions for moving bounds in and out of them are extremely
frequent. They potentially happen every time a register pointing to
memory is dereferenced. Any direct kernel involvement (like a syscall)
to access the tables would obviously destroy performance.
==== Why not do this in userspace? ====
This patch is obviously doing this allocation in the kernel.
However, MPX does not strictly *require* anything in the kernel.
It can theoretically be done completely from userspace. Here are
a few ways this *could* be done. I don't think any of them are
practical in the real-world, but here they are.
Q: Can virtual space simply be reserved for the bounds tables so
that we never have to allocate them?
A: As noted earlier, these tables are *HUGE*. An X-GB virtual
area needs 4*X GB of virtual space, plus 2GB for the bounds
directory. If we were to preallocate them for the 128TB of
user virtual address space, we would need to reserve 512TB+2GB,
which is larger than the entire virtual address space today.
This means they can not be reserved ahead of time. Also, a
single process's pre-popualated bounds directory consumes 2GB
of virtual *AND* physical memory. IOW, it's completely
infeasible to prepopulate bounds directories.
Q: Can we preallocate bounds table space at the same time memory
is allocated which might contain pointers that might eventually
need bounds tables?
A: This would work if we could hook the site of each and every
memory allocation syscall. This can be done for small,
constrained applications. But, it isn't practical at a larger
scale since a given app has no way of controlling how all the
parts of the app might allocate memory (think libraries). The
kernel is really the only place to intercept these calls.
Q: Could a bounds fault be handed to userspace and the tables
allocated there in a signal handler instead of in the kernel?
A: (thanks to tglx) mmap() is not on the list of safe async
handler functions and even if mmap() would work it still
requires locking or nasty tricks to keep track of the
allocation state there.
Having ruled out all of the userspace-only approaches for managing
bounds tables that we could think of, we create them on demand in
the kernel.
Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151829.AD4310DE@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch sets bound violation fields of siginfo struct in #BR
exception handler by decoding the user instruction and constructing
the faulting pointer.
We have to be very careful when decoding these instructions. They
are completely controlled by userspace and may be changed at any
time up to and including the point where we try to copy them in to
the kernel. They may or may not be MPX instructions and could be
completely invalid for all we know.
Note: This code is based on Qiaowei Ren's specialized MPX
decoder, but uses the generic decoder whenever possible. It was
tested for robustness by generating a completely random data
stream and trying to decode that stream. I also unmapped random
pages inside the stream to test the "partial instruction" short
read code.
We kzalloc() the siginfo instead of stack allocating it because
we need to memset() it anyway, and doing this makes it much more
clear when it got initialized by the MPX instruction decoder.
Changes from the old decoder:
* Use the generic decoder instead of custom functions. Saved
~70 lines of code overall.
* Remove insn->addr_bytes code (never used??)
* Make sure never to possibly overflow the regoff[] array, plus
check the register range correctly in 32 and 64-bit modes.
* Allow get_reg() to return an error and have mpx_get_addr_ref()
handle when it sees errors.
* Only call insn_get_*() near where we actually use the values
instead if trying to call them all at once.
* Handle short reads from copy_from_user() and check the actual
number of read bytes against what we expect from
insn_get_length(). If a read stops in the middle of an
instruction, we error out.
* Actually check the opcodes intead of ignoring them.
* Dynamically kzalloc() siginfo_t so we don't leak any stack
data.
* Detect and handle decoder failures instead of ignoring them.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151828.5BDD0915@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We have chosen to perform the allocation of bounds tables in
kernel (See the patch "on-demand kernel allocation of bounds
tables") and to mark these VMAs with VM_MPX.
However, there is currently no suitable interface to actually do
this. Existing interfaces, like do_mmap_pgoff(), have no way to
set a modified ->vm_ops or ->vm_flags and don't hold mmap_sem
long enough to let a caller do it.
This patch wraps mmap_region() and hold mmap_sem long enough to
make the modifications to the VMA which we need.
Also note the 32/64-bit #ifdef in the header. We actually need
to do this at runtime eventually. But, for now, we don't support
running 32-bit binaries on 64-bit kernels. Support for this will
come in later patches.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151827.CE440F67@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This allows us to use cpu_feature_enabled(X86_FEATURE_MPX) as
both a runtime and compile-time check.
When CONFIG_X86_INTEL_MPX is disabled,
cpu_feature_enabled(X86_FEATURE_MPX) will evaluate at
compile-time to 0. If CONFIG_X86_INTEL_MPX=y, then the cpuid
flag will be checked at runtime.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151823.B358EAD2@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
According to Intel SDM extension, MPX configuration and status registers
should be BNDCFGU and BNDSTATUS. This patch renames cfg_reg_u and
status_reg to bndcfgu and bndstatus.
[ tglx: Renamed 'struct bndscr_struct' to 'struct bndscr' ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Link: http://lkml.kernel.org/r/20141114151817.031762AC@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Consider the bndX MPX registers. There 4 registers each
containing a 64-bit lower and a 64-bit upper bound. That's 8*64
bits and we declare it thusly:
struct bndregs_struct {
u64 bndregs[8];
}
Let's say you want to read the upper bound from the MPX register
bnd2 out of the xsave buf. You do:
bndregno = 2;
upper_bound = xsave_buf->bndregs.bndregs[2*bndregno+1];
That kinda sucks. Every time you access it, you need to know:
1. Each bndX register is two entries wide in "bndregs"
2. The lower comes first followed by upper. We do the +1 to get
upper vs. lower.
This replaces the old definition. You can now access them
indexed by the register number directly, and with a meaningful
name for the lower and upper bound:
bndregno = 2;
xsave_buf->bndreg[bndregno].upper_bound;
It's now *VERY* clear that there are 4 registers. The programmer
now doesn't have to care what order the lower and upper bounds
are in, and it's harder to get it wrong.
[ tglx: Changed ub/lb to upper_bound/lower_bound and renamed struct
bndreg_struct to struct bndreg ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: "Yu, Fenghua" <fenghua.yu@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141031215820.5EA5E0EC@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The current x86 instruction decoder steps along through the
instruction stream but always ensures that it never steps farther
than the largest possible instruction size (MAX_INSN_SIZE).
The MPX code is now going to be doing some decoding of userspace
instructions. We copy those from userspace in to the kernel and
they're obviously completely untrusted coming from userspace. In
addition to the constraint that instructions can only be so long,
we also have to be aware of how long the buffer is that came in
from userspace. This _looks_ to be similar to what the perf and
kprobes is doing, but it's unclear to me whether they are
affected.
The whole reason we need this is that it is perfectly valid to be
executing an instruction within MAX_INSN_SIZE bytes of an
unreadable page. We should be able to gracefully handle short
reads in those cases.
This adds support to the decoder to record how long the buffer
being decoded is and to refuse to "validate" the instruction if
we would have gone over the end of the buffer to decode it.
The kprobes code probably needs to be looked at here a bit more
carefully. This patch still respects the MAX_INSN_SIZE limit
there but the kprobes code does look like it might be able to
be a bit more strict than it currently is.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: x86@kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20141114153957.E6B01535@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
apic_find_highest_irr assumes irr_pending is set if any vector in APIC_IRR is
set. If this assumption is broken and apicv is disabled, the injection of
interrupts may be deferred until another interrupt is delivered to the guest.
Ultimately, if no other interrupt should be injected to that vCPU, the pending
interrupt may be lost.
commit 56cc2406d6 ("KVM: nVMX: fix "acknowledge interrupt on exit" when APICv
is in use") changed the behavior of apic_clear_irr so irr_pending is cleared
after setting APIC_IRR vector. After this commit, if apic_set_irr and
apic_clear_irr run simultaneously, a race may occur, resulting in APIC_IRR
vector set, and irr_pending cleared. In the following example, assume a single
vector is set in IRR prior to calling apic_clear_irr:
apic_set_irr apic_clear_irr
------------ --------------
apic->irr_pending = true;
apic_clear_vector(...);
vec = apic_search_irr(apic);
// => vec == -1
apic_set_vector(...);
apic->irr_pending = (vec != -1);
// => apic->irr_pending == false
Nonetheless, it appears the race might even occur prior to this commit:
apic_set_irr apic_clear_irr
------------ --------------
apic->irr_pending = true;
apic->irr_pending = false;
apic_clear_vector(...);
if (apic_search_irr(apic) != -1)
apic->irr_pending = true;
// => apic->irr_pending == false
apic_set_vector(...);
Fixing this issue by:
1. Restoring the previous behavior of apic_clear_irr: clear irr_pending, call
apic_clear_vector, and then if APIC_IRR is non-zero, set irr_pending.
2. On apic_set_irr: first call apic_set_vector, then set irr_pending.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Logical destination mode can be used to send NMI IPIs even when all
APICs are software disabled, so if all APICs are software disabled we
should still look at the DFRs.
So the DFRs should all be the same, even if some or all APICs are
software disabled. However, the SDM does not say this, so tweak
the logic as follows:
- if one APIC is enabled and has LDR != 0, use that one to build the map.
This picks the right DFR in case an OS is only setting it for the
software-enabled APICs, or in case an OS is using logical addressing
on some APICs while leaving the rest in reset state (using LDR was
suggested by Radim).
- if all APICs are disabled, pick a random one to build the map.
We use the last one with LDR != 0 for simplicity.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, the APIC logical map does not consider VCPUs whose local-apic is
software-disabled. However, NMIs, INIT, etc. should still be delivered to such
VCPUs. Therefore, the APIC mode should first be determined, and then the map,
considering all VCPUs should be constructed.
To address this issue, first find the APIC mode, and only then construct the
logical map.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull x86 fixes from Ingo Molnar:
"Microcode fixes, a Xen fix and a KASLR boot loading fix with certain
memory layouts"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, microcode, AMD: Fix ucode patch stashing on 32-bit
x86/core, x86/xen/smp: Use 'die_complete' completion when taking CPU down
x86, microcode: Fix accessing dis_ucode_ldr on 32-bit
x86, kaslr: Prevent .bss from overlaping initrd
x86, microcode, AMD: Fix early ucode loading on 32-bit
Al Viro pointed out that the x86-64 csum_partial_copy_from_user() is
somewhat confused about what it should do on errors, notably it mostly
clears the uncopied end result buffer, but misses that for the initial
alignment case.
All users should check for errors, so it's dubious whether the clearing
is even necessary, and Al also points out that we should probably clean
up the calling conventions, but regardless of any future changes to this
function, the fact that it is inconsistent is just annoying.
So make the __get_user() failure path use the same error exit as all the
other errors do.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Miller <davem@davemloft.net>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit e00c8cc93c "x86: Use new cache mode type in memtype related
functions" broke the ARCH=um build.
arch/x86/include/asm/cacheflush.h:67:36: error: return type is an incomplete type
static inline enum page_cache_mode get_page_memtype(struct page *pg)
The reason is simple. get_page_memtype() and set_page_memtype()
require enum page_cache_mode now, which is defined in
asm/pgtable_types.h. UM does not include that file for obvious reasons.
The simple solution is to move that functions to arch/x86/mm/pat.c
where the only callsites of this are located. They should have been
there in the first place.
Fixes: e00c8cc93c "x86: Use new cache mode type in memtype related functions"
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Richard Weinberger <richard@nod.at>
We have some very similarly named command-line options:
arch/x86/kernel/cpu/common.c:__setup("noxsave", x86_xsave_setup);
arch/x86/kernel/cpu/common.c:__setup("noxsaveopt", x86_xsaveopt_setup);
arch/x86/kernel/cpu/common.c:__setup("noxsaves", x86_xsaves_setup);
__setup() is designed to match options that take arguments, like
"foo=bar" where you would have:
__setup("foo", x86_foo_func...);
The problem is that "noxsave" actually _matches_ "noxsaves" in
the same way that "foo" matches "foo=bar". If you boot an old
kernel that does not know about "noxsaves" with "noxsaves" on the
command line, it will interpret the argument as "noxsave", which
is not what you want at all.
This makes the "noxsave" handler only return success when it finds
an *exact* match.
[ tglx: We really need to make __setup() more robust. ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: x86@kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20141111220133.FE053984@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
PEBS can capture machine state regs at retiremnt of the sampled
instructions. When precise sampling is enabled on an event, PEBS
is used, so substitute the interrupted state with the PEBS state.
Note that not all registers are captured by PEBS. Those missing
are replaced by the interrupt state counter-parts.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1411559322-16548-3-git-send-email-eranian@google.com
Cc: cebbert.lkml@gmail.com
Cc: jolsa@redhat.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Disallow setting inv/cmask/etc. flags for all PEBS events
on these CPUs, except for the UOPS_RETIRED.* events on Nehalem/Westmere,
which are needed for cycles:p. This avoids an undefined situation
strongly discouraged by the Intle SDM. The PLD_* events were already
covered. This follows the earlier changes for Sandy Bridge and alter.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/1411569288-5627-3-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
My earlier commit:
86a04461a9 ("perf/x86: Revamp PEBS event selection")
made nearly all PEBS on Sandy/IvyBridge/Haswell to reject non zero flags.
However this wasn't done for the INST_RETIRED.PREC_DIST event
because no suitable macro existed. Now that we have
INTEL_FLAGS_UEVENT_CONSTRAINT enforce zero flags for
INST_RETIRED.PREC_DIST too.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/1411569288-5627-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a FLAGS_UEVENT_CONSTRAINT macro that allows us to
match on event+umask, and in additional all flags.
This is needed to ensure the INV and CMASK fields
are zero for specific events, as this can cause undefined
behavior.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com>
Cc: Mark Davies <junk@eslaf.co.uk>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1411569288-5627-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add scaling to MB/s to the memory controller read/write
events for Sandy/IvyBridge/Haswell-EP similar to how the client
does. This makes the events easier to use from the
standard perf tool.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/1415062828-19759-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
At the moment there are a lot of places that handle setting or getting
the page cache mode by treating the pgprot bits equal to the cache mode.
This is only true because there are a lot of assumptions about the setup
of the PAT MSR. Otherwise the cache type needs to get translated into
pgprot bits and vice versa.
This patch tries to prepare for that by introducing a separate type
for the cache mode and adding functions to translate between those and
pgprot values.
To avoid too much performance penalty the translation between cache mode
and pgprot values is done via tables which contain the relevant
information. Write-back cache mode is hard-wired to be 0, all other
modes are configurable via those tables. For large pages there are
translation functions as the PAT bit is located at different positions
in the ptes of 4k and large pages.
Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stefan.bader@canonical.com
Cc: xen-devel@lists.xensource.com
Cc: konrad.wilk@oracle.com
Cc: ville.syrjala@linux.intel.com
Cc: david.vrabel@citrix.com
Cc: jbeulich@suse.com
Cc: toshi.kani@hp.com
Cc: plagnioj@jcrosoft.com
Cc: tomi.valkeinen@ti.com
Cc: bhelgaas@google.com
Link: http://lkml.kernel.org/r/1415019724-4317-2-git-send-email-jgross@suse.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Another attempt at moving x86 to libstub taking advantage of the
__pure attribute - Ard Biesheuvel
* Add EFI runtime services section to ptdump - Mathias Krause
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi
Pull EFI updates for v3.19 from Matt Fleming:
- Support module unload for efivarfs - Mathias Krause
- Another attempt at moving x86 to libstub taking advantage of the
__pure attribute - Ard Biesheuvel
- Add EFI runtime services section to ptdump - Mathias Krause
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There were several reports that on some systems writing the SBOX0 PMU
initialization MSR would #GP at boot. This did not happen on all
systems -- my two test systems booted fine.
Writing the three initialization bits bit-by-bit seems to avoid the
problem. So add a special callback to do just that.
This replaces an earlier patch that disabled the SBOX.
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Reported-and-Tested-by: Patrick Lu <patrick.lu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/1415062828-19759-4-git-send-email-andi@firstfloor.org
[ Fixed a whitespace error and added attribution tags that were left out inexplicably. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The counter register offsets for the IRP box PMU for Haswell-EP
were incorrect. The offsets actually changed over IvyBridge EP.
Fix them to the correct values. For this we need to fork the read
function from the IVB and use an own counter array.
Tested-by: patrick.lu@intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/1415062828-19759-3-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the 3 private slots, this gives us 512 slots total.
Motivation for this is in addition to assigned devices
support more memory hotplug slots, where 1 slot is
used by a hotplugged memory stick.
It will allow to support upto 256 hotplug memory
slots and leave 253 slots for assigned devices and
other devices that use them.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When running the tsc_adjust kvm-unit-test on an AMD processor with the
IA32_TSC_ADJUST feature enabled, the WARN_ON in svm_adjust_tsc_offset can be
triggered. This WARN_ON checks for a negative adjustment in case __scale_tsc
is called; however it may trigger unnecessary warnings.
This patch moves the WARN_ON to trigger only if __scale_tsc will actually be
called from svm_adjust_tsc_offset. In addition make adj in kvm_set_msr_common
s64 since this can have signed values.
Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The only place where the time is invalid is when the ACPI_CSTATE_FFH entry
method is not set. Otherwise for all the drivers, the time can be correctly
measured.
Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers
for all the states, just invert the logic by replacing it by the flag
CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle
driver, remove the former flag from all the drivers and invert the logic with
this flag in the different governor.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There's nothing to switch if the host and guest values are the same.
I am unable to find evidence that this makes any difference
whatsoever.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
[I could see a difference on Nehalem. From 5 runs:
userspace exit, guest!=host 12200 11772 12130 12164 12327
userspace exit, guest=host 11983 11780 11920 11919 12040
lightweight exit, guest!=host 3214 3220 3238 3218 3337
lightweight exit, guest=host 3178 3193 3193 3187 3220
This passes the t-test with 99% confidence for userspace exit,
98.5% confidence for lightweight exit. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
New Fam15h models carry extra feature bits and extend
the MSR register space for IBS ops. Adding them here.
While at it, add functionality to read IbsBrTarget and
OpData4 depending on their availability if user wants a
PERF_SAMPLE_RAW.
Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <paulus@samba.org>
Cc: <acme@kernel.org>
Link: http://lkml.kernel.org/r/1415651066-13523-1-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'v3.18-rc4' into x86/cleanups, to refresh the tree before pulling new changes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
At least on Sandy Bridge, letting the CPU switch IA32_EFER is much
faster than switching it manually.
I benchmarked this using the vmexit kvm-unit-test (single run, but
GOAL multiplied by 5 to do more iterations):
Test Before After Change
cpuid 2000 1932 -3.40%
vmcall 1914 1817 -5.07%
mov_from_cr8 13 13 0.00%
mov_to_cr8 19 19 0.00%
inl_from_pmtimer 19164 10619 -44.59%
inl_from_qemu 15662 10302 -34.22%
inl_from_kernel 3916 3802 -2.91%
outl_to_kernel 2230 2194 -1.61%
mov_dr 172 176 2.33%
ipi (skipped) (skipped)
ipi+halt (skipped) (skipped)
ple-round-robin 13 13 0.00%
wr_tsc_adjust_msr 1920 1845 -3.91%
rd_tsc_adjust_msr 1892 1814 -4.12%
mmio-no-eventfd:pci-mem 16394 11165 -31.90%
mmio-wildcard-eventfd:pci-mem 4607 4645 0.82%
mmio-datamatch-eventfd:pci-mem 4601 4610 0.20%
portio-no-eventfd:pci-io 11507 7942 -30.98%
portio-wildcard-eventfd:pci-io 2239 2225 -0.63%
portio-datamatch-eventfd:pci-io 2250 2234 -0.71%
I haven't explicitly computed the significance of these numbers,
but this isn't subtle.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
[The results were reproducible on all of Nehalem, Sandy Bridge and
Ivy Bridge. The slowness of manual switching is because writing
to EFER with WRMSR triggers a TLB flush, even if the only bit you're
touching is SCE (so the page table format is not affected). Doing
the write as part of vmentry/vmexit, instead, does not flush the TLB,
probably because all processors that have EPT also have VPID. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Merge tag 'v3.18-rc4' into drm-next
backmerge to get vmwgfx locking changes into next as the
conflict with per-plane locking.
Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.
With HWP enbaled intel_pstate will no longer be responsible for selecting P
states for the processor. intel_pstate will continue to register to
the cpufreq core as the scaling driver for CPUs implementing
HWP. In HWP mode intel_pstate provides three functions reporting
frequency to the cpufreq core, support for the set_policy() interface
from the core and maintaining the intel_pstate sysfs interface in
/sys/devices/system/cpu/intel_pstate. User preferences expressed via
the set_policy() interface or the sysfs interface are forwared to the
CPU via the HWP MSR interface.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.
One bit CPUID.06H:EAX[bit 7] expresses the presence of the HWP feature on
the processor. The remaining bits CPUID.06H:EAX[bit 8-11] denote the
presense of various HWP features.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In commit 3891a04aaf ("x86-64, espfix: Don't leak bits 31:16 of %esp
returning..") the "ESPFix Area" was added to the page table dump special
sections. That area, though, has a limited amount of entries printed.
The EFI runtime services are, unfortunately, located in-between the
espfix area and the high kernel memory mapping. Due to the enforced
limitation for the espfix area, the EFI mappings won't be printed in the
page table dump.
To make the ESP runtime service mappings visible again, provide them a
dedicated entry.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This reverts commit 84be880560, which itself reverted my original
attempt to move x86 from #include'ing .c files from across the tree
to using the EFI stub built as a static library.
The issue that affected the original approach was that splitting
the implementation into several .o files resulted in the variable
'efi_early' becoming a global with external linkage, which under
-fPIC implies that references to it must go through the GOT. However,
dealing with this additional GOT entry turned out to be troublesome
on some EFI implementations. (GCC's visibility=hidden attribute is
supposed to lift this requirement, but it turned out not to work on
the 32-bit build.)
Instead, use a pure getter function to get a reference to efi_early.
This approach results in no additional GOT entries being generated,
so there is no need for any changes in the early GOT handling.
Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
The problem fixed by 0e4ccb1505 ("PCI: Add x86_msi.msi_mask_irq() and
msix_mask_irq()") has been fixed in a simpler way by a previous commit
("PCI/MSI: Add pci_msi_ignore_mask to prevent writes to MSI/MSI-X Mask
Bits").
The msi_mask_irq() and msix_mask_irq() x86_msi_ops added by 0e4ccb1505
are no longer needed, so revert the commit.
default_msi_mask_irq() and default_msix_mask_irq() were added by
0e4ccb1505 and are still used by s390, so keep them for now.
[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: xen-devel@lists.xenproject.org
With the introduction of the dynamic trampolines, it is useful that if
things go wrong that ftrace_bug() produces more information about what
the current state is. This can help debug issues that may arise.
Ftrace has lots of checks to make sure that the state of the system it
touchs is exactly what it expects it to be. When it detects an abnormality
it calls ftrace_bug() and disables itself to prevent any further damage.
It is crucial that ftrace_bug() produces sufficient information that
can be used to debug the situation.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Borislav Petkov <bp@suse.de>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When the static ftrace_ops (like function tracer) enables tracing, and it
is the only callback that is referencing a function, a trampoline is
dynamically allocated to the function that calls the callback directly
instead of calling a loop function that iterates over all the registered
ftrace ops (if more than one ops is registered).
But when it comes to dynamically allocated ftrace_ops, where they may be
freed, on a CONFIG_PREEMPT kernel there's no way to know when it is safe
to free the trampoline. If a task was preempted while executing on the
trampoline, there's currently no way to know when it will be off that
trampoline.
But this is not true when it comes to !CONFIG_PREEMPT. The current method
of calling schedule_on_each_cpu() will force tasks off the trampoline,
becaues they can not schedule while on it (kernel preemption is not
configured). That means it is safe to free a dynamically allocated
ftrace ops trampoline when CONFIG_PREEMPT is not configured.
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Previous versions of the espfix had a single function which did setup
the pagetables. It was later split into BSP and AP version. Drop unused
leftovers after that split.
Signed-off-by: Borislav Petkov <bp@suse.de>
* access the dis_ucode_ldr chicken bit properly
* fix patch stashing on AMD on 32-bit
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Merge tag 'microcode_fixes_for_3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/urgent
Pull two fixes for early microcode loader on 32-bit from Borislav Petkov:
- access the dis_ucode_ldr chicken bit properly
- fix patch stashing on AMD on 32-bit
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The xlate_dev_{kmem,mem}_ptr() functions take either a physical address
or a kernel virtual address, so data types should be phys_addr_t and
void *. They both return a kernel virtual address which is only ever
used in calls to copy_{from,to}_user(), so make variables that store it
void * rather than char * for consistency.
Also only define a weak unxlate_dev_mem_ptr() function if architectures
haven't overridden them in the asm/io.h header file.
Signed-off-by: Thierry Reding <treding@nvidia.com>
PCIDs are only supported in 64-bit mode. No need to clear bit 63
of CR3 unless the host is 64-bit.
Reported by Fengguang Wu's autobuilder.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Save the patch while we're running on the BSP instead of later, before
the initrd has been jettisoned. More importantly, on 32-bit we need to
access the physical address instead of the virtual.
This way we actually do find it on the APs instead of having to go
through the initrd each time.
Tested-by: Richard Hendershot <rshendershot@mchsi.com>
Fixes: 5335ba5cf4 ("x86, microcode, AMD: Fix early ucode loading")
Cc: <stable@vger.kernel.org> # v3.13+
Signed-off-by: Borislav Petkov <bp@suse.de>
Commit 2ed53c0d6c ("x86/smpboot: Speed up suspend/resume by
avoiding 100ms sleep for CPU offline during S3") introduced
completions to CPU offlining process. These completions are not
initialized on Xen kernels causing a panic in
play_dead_common().
Move handling of die_complete into common routines to make them
available to Xen guests.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: tianyu.lan@intel.com
Cc: konrad.wilk@oracle.com
Cc: xen-devel@lists.xenproject.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1414770572-7950-1-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The vsyscall emulation code sets orig_ax for seccomp's benefit,
but it forgot to set it back.
I'm not sure that this is observable at all, but it could cause
confusion to various /proc or ptrace users, and it's possible
that it could cause minor artifacts if a signal were to be
delivered on return from vsyscall emulation.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/cdc6a564517a4df09235572ee5f530ccdcf933f7.1415144089.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The new trace event records:
* the id of vcpu being updated
* the pvclock_vcpu_time_info struct being written to guest memory
This is useful for debugging pvclock bugs, such as the bug fixed by
"[PATCH] kvm: x86: Fix kvm clock versioning.".
Signed-off-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm updates the version number for the guest paravirt clock structure by
incrementing the version of its private copy. It does not read the guest
version, so will write version = 2 in the first update for every new VM,
including after restoring a saved state. If guest state is saved during
reading the clock, it could read and accept struct fields and guest TSC
from two different updates. This changes the code to increment the guest
version and write it back.
Signed-off-by: Owen Hofmann <osh@google.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 3b32004a66 ("KVM: x86: movnti minimum op size of 32-bit is not kept")
did not fully fix the minimum operand size of MONTI emulation. Still, MOVNTI
may be mistakenly performed using 16-bit opsize.
This patch add No16 flag to mark an instruction does not support 16-bits
operand size.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the guest writes to the TSC, the masterclock TSC copy must be
updated as well along with the TSC_OFFSET update, otherwise a negative
tsc_timestamp is calculated at kvm_guest_time_update.
Once "if (!vcpus_matched && ka->use_master_clock)" is simplified to
"if (ka->use_master_clock)", the corresponding "if (!ka->use_master_clock)"
becomes redundant, so remove the do_request boolean and collapse
everything into a single condition.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that KVM injects #UD on "unhandlable" error, it makes better sense to
return such error on sysenter instead of directly injecting #UD to the guest.
This allows to track more easily the unhandlable cases the emulator does not
support.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APIC base relocation is unsupported by KVM. If anyone uses it, the least should
be to report a warning in the hypervisor.
Note that KVM-unit-tests uses this feature for some reason, so running the
tests triggers the warning.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 7fe864dc94 (KVM: x86: Mark VEX-prefix instructions emulation as
unimplemented, 2014-06-02) marked VEX instructions as such in protected
mode. VEX-prefix instructions are not supported relevant on real-mode
and VM86, but should cause #UD instead of being decoded as LES/LDS.
Fix this behaviour to be consistent with real hardware.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
[Check for mod == 3, rather than 2 or 3. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Many sysfs *_show function use cpu{list,mask}_scnprintf to copy cpumap
to the buffer aligned to PAGE_SIZE, append '\n' and '\0' to return null
terminated buffer with newline.
This patch creates a new helper function cpumap_print_to_pagebuf in
cpumask.h using newly added bitmap_print_to_pagebuf and consolidates
most of those sysfs functions using the new helper function.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: x86@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Task-switch emulation checks the privilege level prior to performing the
task-switch. This check is incorrect in the case of task-gates, in which the
tss.dpl is ignored, and can cause superfluous exceptions. Moreover this check
is unnecassary, since the CPU checks the privilege levels prior to exiting.
Intel SDM 25.4.2 says "If CALL or JMP accesses a TSS descriptor directly
outside IA-32e mode, privilege levels are checked on the TSS descriptor" prior
to exiting. AMD 15.14.1 says "The intercept is checked before the task switch
takes place but after the incoming TSS and task gate (if one was involved) have
been checked for correctness."
This patch removes the CPL checks for CALL and JMP.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When emulating LTR/LDTR/LGDT/LIDT, #GP should be injected if the base is
non-canonical. Otherwise, VM-entry will fail.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
LGDT and LIDT emulation logic is almost identical. Merge the logic into a
single point to avoid redundancy. This will be used by the next patch that
will ensure the bases of the loaded GDTR and IDTR are canonical.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the emulation ends in fault, eflags should not be updated. However, several
instruction emulations (actually all the fastops) currently update eflags, if
the fault was detected afterwards (e.g., #PF during writeback).
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Although Intel SDM mentions bit 63 is reserved, MOV to CR3 can have bit 63 set.
As Intel SDM states in section 4.10.4 "Invalidation of TLBs and
Paging-Structure Caches": " MOV to CR3. ... If CR4.PCIDE = 1 and bit 63 of the
instruction’s source operand is 0 ..."
In other words, bit 63 is not reserved. KVM emulator currently consider bit 63
as reserved. Fix it.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
According to Intel SDM push of segment selectors is done in the following
manner: "if the operand size is 32-bits, either a zero-extended value is pushed
on the stack or the segment selector is written on the stack using a 16-bit
move. For the last case, all recent Core and Atom processors perform a 16-bit
move, leaving the upper portion of the stack location unmodified."
This patch modifies the behavior to match the core behavior.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CMPS and SCAS instructions are evaluated in the wrong order. For reference (of
CMPS), see http://www.fermimn.gov.it/linux/quarta/x86/cmps.htm : "Note that the
direction of subtraction for CMPS is [SI] - [DI] or [ESI] - [EDI]. The left
operand (SI or ESI) is the source and the right operand (DI or EDI) is the
destination. This is the reverse of the usual Intel convention in which the
left operand is the destination and the right operand is the source."
Introducing em_cmp_r for this matter that performs comparison in reverse order
using fastop infrastructure to avoid a wrapper function.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SYSCALL emulation currently clears in 64-bit mode eflags according to
MSR_SYSCALL_MASK. However, on bare-metal eflags[1] which is fixed to one
cannot be cleared, even if MSR_SYSCALL_MASK masks the bit. This wrong behavior
may result in failed VM-entry, as VT disallows entry with eflags[1] cleared.
This patch sets the bit after masking eflags on syscall.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In x86, you can only MOV-sreg to memory with either 16-bits or 64-bits size.
In contrast, KVM may write to 32-bits memory on MOV-sreg. This patch fixes KVM
behavior, and sets the destination operand size to two, if the destination is
memory.
When destination is registers, and the operand size is 32-bits, the high
16-bits in modern CPUs is filled with zero. This is handled correctly.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
x86 debug registers hold a linear address. Therefore, breakpoints detection
should consider CS.base, and check whether instruction linear address equals
(CS.base + RIP). This patch introduces a function to evaluate RIP linear
address and uses it for breakpoints detection.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
DR6[0:3] (previous breakpoint indications) are cleared when #DB is injected
during handle_exception, just as real hardware does. Similarily, handle_dr
should clear DR6[0:3].
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Real-mode exceptions do not deliver error code. As can be seen in Intel SDM
volume 2, real-mode exceptions do not have parentheses, which indicate
error-code. To avoid significant changes of the code, the error code is
"removed" during exception queueing.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In one occassion, decode_modrm uses the rm field after it is extended with
REX.B to determine the addressing mode. Doing so causes it not to read the
offset for rip-relative addressing with REX.B=1.
This patch moves the fetch where we already mask REX.B away instead.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A bug was reported as follows: when running Windows 7 32-bit guests on qemu-kvm,
sometimes the guests run into blue screen during reboot. The problem was that a
guest's RVI was not cleared when it rebooted. This patch has fixed the problem.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Tested-by: Rongrong Liu <rongrongx.liu@intel.com>, Da Chun <ngugc@qq.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Return a negative error code instead, and WARN() when we should be covering
the entire 2-bit space of vmcs_field_type's return value. For increased
robustness, add a BUILD_BUG_ON checking the range of vmcs_field_to_offset.
Suggested-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of vmx_init(), actually it would make reasonable sense to do
anything specific to vmx hardware setting in vmx_x86_ops->hardware_setup().
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Just move this pair of functions down to make sure later we can
add something dependent on others.
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
MSI-X vector Mask Bits are in MSI-X Tables in PCI memory space. Xen PV
guests can't write to those tables. MSI vector Mask Bits are in PCI
configuration space. Xen PV guests can write to config space, but those
writes are ignored.
Commit 0e4ccb1505 ("PCI: Add x86_msi.msi_mask_irq() and
msix_mask_irq()") added a way to override default_mask_msi_irqs() and
default_mask_msix_irqs() so they can be no-ops in Xen guests, but this is
more complicated than necessary.
Add "pci_msi_ignore_mask" in the core PCI MSI code. If set,
default_mask_msi_irqs() and default_mask_msix_irqs() return without doing
anything. This is less flexible, but much simpler.
[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: xen-devel@lists.xenproject.org
The CPP identifier 'HAS_PCBC' is defined when the Kconfig
option CRYPTO_PCBC is set as 'y' or 'm', and is further
used in two ifdef blocks to conditionally compile source
code. This indirection hides the actual Kconfig dependency
and complicates readability. Moreover, it's inconsistent
with the rest of the ifdef blocks in the file, which
directly reference Kconfig options.
This patch removes 'HAS_PCBC' and replaces its occurrences
with the actual dependency on 'CRYPTO_PCBC' being set as
'y' or 'm'.
Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We should be accessing it through a pointer, like on the BSP.
Tested-by: Richard Hendershot <rshendershot@mchsi.com>
Fixes: 65cef1311d ("x86, microcode: Add a disable chicken bit")
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: Borislav Petkov <bp@suse.de>
The emulator could reuse an op->type from a previous instruction for some
immediate values. If it mistakenly considers the operands as memory
operands, it will performs a memory read and overwrite op->val.
Consider for instance the ROR instruction - src2 (the number of times)
would be read from memory instead of being used as immediate.
Mark every immediate operand as such to avoid this problem.
Cc: stable@vger.kernel.org
Fixes: c44b4c6ab8
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Observing that per-CPU data (in the SMP case) is reachable by
exploiting 64-bit address wraparound (building on the default kernel
load address being at 16Mb), the one byte shorter RIP-relative
addressing form can be used for most per-CPU accesses. The one
exception are the "stable" reads, where the use of the "P" operand
modifier prevents the compiler from using RIP-relative addressing, but
is unavoidable due to the use of the "p" constraint (side note: with
gcc 4.9.x the intended effect of this isn't being achieved anymore,
see gcc bug 63637).
With the dependency on the minimum kernel load address, arbitrarily
low values for CONFIG_PHYSICAL_START are now no longer possible. A
link time assertion is being added, directing to the need to increase
that value when it triggers.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/5458A1780200007800044A9D@mail.emea.novell.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Both this_cpu_off and cpu_info aren't getting modified post boot, yet
are being accessed on enough code paths that grouping them with other
frequently read items seems desirable. For cpu_info this at the same
time implies removing the cache line alignment (which afaict became
pointless when it got converted to per-CPU data years ago).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/54589BD20200007800044A84@mail.emea.novell.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On large-memory x86-64 systems of 64GB or more with memory hot-plug
enabled, use a 2GB memory block size. Eg with 64GB memory, this reduces
the number of directories in /sys/devices/system/memory from 512 to 32,
making it more manageable, and reducing the creation time accordingly.
This caveat is that the memory can't be offlined (for hotplug or
otherwise) with the finer default 128MB granularity, but this is
unimportant due to the high memory densities generally used with such
large-memory systems, where eg a single DIMM is the order of 16GB.
Signed-off-by: Daniel J Blueman <daniel@numascale.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1415089784-28779-4-git-send-email-daniel@numascale.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Drop printing that serves no purpose, as it's printing fixed or known
values, and mark constant structure appropriately.
Signed-off-by: Daniel J Blueman <daniel@numascale.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1415089784-28779-3-git-send-email-daniel@numascale.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The default self-IPI path polls the ICR to delay sending the IPI until
there is no IPI in progress. This is redundant on x86-86 APICs, since
IPIs are queued. See the AMD64 Architecture Programmer's Manual, vol 2,
p525.
Signed-off-by: Daniel J Blueman <daniel@numascale.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1415089784-28779-2-git-send-email-daniel@numascale.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Prevent 16-bit APIC IDs being truncated by using correct mask. This fixes
booting large systems, where the wrong core would receive the startup and
init IPIs, causing hanging.
Signed-off-by: Daniel J Blueman <daniel@numascale.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1415089784-28779-1-git-send-email-daniel@numascale.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This adds CONFIG_X86_VSYSCALL_EMULATION, guarded by CONFIG_EXPERT.
Turning it off completely disables vsyscall emulation, saving ~3.5k
for vsyscall_64.c, 4k for vsyscall_emu_64.S (the fake vsyscall
page), some tiny amount of core mm code that supports a gate area,
and possibly 4k for a wasted pagetable. The latter is because the
vsyscall addresses are misaligned and fit poorly in the fixmap.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/406db88b8dd5f0cbbf38216d11be34bbb43c7eae.1414618407.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
vsyscall_64.c is just vsyscall emulation. Tidy it up accordingly.
[ tglx: Preserved the original copyright notices ]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/9c448d5643d0fdb618f8cde9a54c21d2bcd486ce.1414618407.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
I see no point in having an unusable read-only page sitting at
0xffffffffff600000 when vsyscall=none. Instead, skip mapping it and
remove it from /proc/PID/maps.
I kept the ratelimited warning when programs try to use a vsyscall
in this mode, since it may help admins avoid confusion.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/0dddbadc1d4e3bfbaf887938ff42afc97a7cc1f2.1414618407.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We have encountered hardware with 18 cores/socket that gives 36 CPUs/socket
with hyperthreading enabled. This exceeds the current MAX_CPUS_PER_SOCKET
causing a failure in get_cpu_topology. Increase MAX_CPUS_PER_SOCKET to 64
and MAX_CPUS_PER_UVHUB to 128.
Signed-off-by: James Custer <jcuster@sgi.com>
Cc: Russ Anderson <rja@sgi.com>
Link: http://lkml.kernel.org/r/1414952199-185319-1-git-send-email-jcuster@sgi.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In init_per_cpu(), when get_cpu_topology() fails, init_per_cpu_tunables()
is not called afterwards. This means that bau_control->statp is NULL.
If a user then reads /proc/sgi_uv/ptc_statistics ptc_seq_show() references
a NULL pointer. Therefore, since uv_bau_init calls set_bau_off when
init_per_cpu() fails, we add code that detects when the bau is off in
ptc_seq_show() to avoid referencing a NULL pointer.
Signed-off-by: James Custer <jcuster@sgi.com>
Cc: Russ Anderson <rja@sgi.com>
Link: http://lkml.kernel.org/r/1414952199-185319-2-git-send-email-jcuster@sgi.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The temp fixed area is only used during boot for early_ioremap(), and
it is unused when ioremap() is functional. vmalloc/pkmap area become
available after early boot so the temp fixed area is available for
re-use.
The virtual address is more precious on i386, especially turning on
high memory. So we can re-use the virtual address space.
Remove the now unused defines FIXADDR_BOOT_START and FIXADDR_BOOT_SIZE.
Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Cc: pbonzini@redhat.com
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/1414582717-32729-1-git-send-email-mnfhuang@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We can use get_cpu() and put_cpu() to replace
preempt_disable()/cpu = smp_processor_id() and
preempt_enable() for slightly better code.
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We mirror a subset of these registers in separate variables.
Using them directly should be faster.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APIC-write VM exits are "trap-like": they save CS:RIP values for the
instruction after the write, and more importantly, the handler will
already see the new value in the virtual-APIC page. This means that
apic_reg_write cannot use kvm_apic_get_reg to omit timer cancelation
when mode changes.
timer_mode_mask shouldn't be changing as it depends on cpuid.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
APIC-write VM exits are "trap-like": they save CS:RIP values for the
instruction after the write, and more importantly, the handler will
already see the new value in the virtual-APIC page.
This caused a bug if you used KVM_SET_IRQCHIP to set the SW-enabled bit
in the SPIV register. The chain of events is as follows:
* When the irqchip is added to the destination VM, the apic_sw_disabled
static key is incremented (1)
* When the KVM_SET_IRQCHIP ioctl is invoked, it is decremented (0)
* When the guest disables the bit in the SPIV register, e.g. as part of
shutdown, apic_set_spiv does not notice the change and the static key is
_not_ incremented.
* When the guest is destroyed, the static key is decremented (-1),
resulting in this trace:
WARNING: at kernel/jump_label.c:81 __static_key_slow_dec+0xa6/0xb0()
jump label: negative count!
[<ffffffff816bf898>] dump_stack+0x19/0x1b
[<ffffffff8107c6f1>] warn_slowpath_common+0x61/0x80
[<ffffffff8107c76c>] warn_slowpath_fmt+0x5c/0x80
[<ffffffff811931e6>] __static_key_slow_dec+0xa6/0xb0
[<ffffffff81193226>] static_key_slow_dec_deferred+0x16/0x20
[<ffffffffa0637698>] kvm_free_lapic+0x88/0xa0 [kvm]
[<ffffffffa061c63e>] kvm_arch_vcpu_uninit+0x2e/0xe0 [kvm]
[<ffffffffa05ff301>] kvm_vcpu_uninit+0x21/0x40 [kvm]
[<ffffffffa067cec7>] vmx_free_vcpu+0x47/0x70 [kvm_intel]
[<ffffffffa061bc50>] kvm_arch_vcpu_free+0x50/0x60 [kvm]
[<ffffffffa061ca22>] kvm_arch_destroy_vm+0x102/0x260 [kvm]
[<ffffffff810b68fd>] ? synchronize_srcu+0x1d/0x20
[<ffffffffa06030d1>] kvm_put_kvm+0xe1/0x1c0 [kvm]
[<ffffffffa06036f8>] kvm_vcpu_release+0x18/0x20 [kvm]
[<ffffffff81215c62>] __fput+0x102/0x310
[<ffffffff81215f4e>] ____fput+0xe/0x10
[<ffffffff810ab664>] task_work_run+0xb4/0xe0
[<ffffffff81083944>] do_exit+0x304/0xc60
[<ffffffff816c8dfc>] ? _raw_spin_unlock_irq+0x2c/0x50
[<ffffffff810fd22d>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[<ffffffff8108432c>] do_group_exit+0x4c/0xc0
[<ffffffff810843b4>] SyS_exit_group+0x14/0x20
[<ffffffff816d33a9>] system_call_fastpath+0x16/0x1b
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The check in kvm_set_lapic_tscdeadline_msr() was trying to prevent a
situation where we lose a pending deadline timer in a MSR write.
Losing it is fine, because it effectively occurs before the timer fired,
so we should be able to cancel or postpone it.
Another problem comes from interaction with QEMU, or other userspace
that can set deadline MSR without a good reason, when timer is already
pending: one guest's deadline request results in more than one
interrupt because one is injected immediately on MSR write from
userspace and one through hrtimer later.
The solution is to remove the injection when replacing a pending timer
and to improve the usual QEMU path, we inject without a hrtimer when the
deadline has already passed.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reported-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make the code reusable.
If the timer was already pending, we shouldn't be waiting in a queue,
so wake_up can be skipped, simplifying the path.
There is no 'reinject' case => the comment is removed.
Current race behaves correctly.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If DR4/5 is accessed when it is unavailable (since CR4.DE is set), then #UD
should be generated even if CPL>0. This is according to Intel SDM Table 6-2:
"Priority Among Simultaneous Exceptions and Interrupts".
Note, that this may happen on the first DR access, even if the host does not
sets debug breakpoints. Obviously, it occurs when the host debugs the guest.
This patch moves the DR4/5 checks from __kvm_set_dr/_kvm_get_dr to handle_dr.
The emulator already checks DR4/5 availability in check_dr_read. Nested
virutalization related calls to kvm_set_dr/kvm_get_dr would not like to inject
exceptions to the guest.
As for SVM, the patch follows the previous logic as much as possible. Anyhow,
it appears the DR interception code might be buggy - even if the DR access
may cause an exception, the instruction is skipped.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When read access is performed using a readable code segment, the "conforming"
and "non-conforming" checks should not be done. As a result, read using
non-conforming readable code segment fails.
This is according to Intel SDM 5.6.1 ("Accessing Data in Code Segments").
The fix is not to perform the "non-conforming" checks if the access is not a
fetch; the relevant checks are already done when loading the segment.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
DR7.LE should be cleared during task-switch. This feature is poorly documented.
For reference, see:
http://pdos.csail.mit.edu/6.828/2005/readings/i386/s12_02.htm
SDM [17.2.4]:
This feature is not supported in the P6 family processors, later IA-32
processors, and Intel 64 processors.
AMD [2:13.1.1.4]:
This bit is ignored by implementations of the AMD64 architecture.
Intel's formulation could mean that it isn't even zeroed, but current
hardware indeed does not behave like that.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In long-mode, when the address size is 4 bytes, the linear address is not
truncated as the emulator mistakenly does. Instead, the offset within the
segment (the ea field) should be truncated according to the address size.
As Intel SDM says: "In 64-bit mode, the effective address components are added
and the effective address is truncated ... before adding the full 64-bit
segment base."
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Intel SDM 17.2.4 (Debug Control Register (DR7)) says: "The processor clears the
GD flag upon entering to the debug exception handler." This sentence may be
misunderstood as if it happens only on #DB due to debug-register protection,
but it happens regardless to the cause of the #DB.
Fix the behavior to match both real hardware and Bochs.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM does not deliver x2APIC broadcast messages with physical mode. Intel SDM
(10.12.9 ICR Operation in x2APIC Mode) states: "A destination ID value of
FFFF_FFFFH is used for broadcast of interrupts in both logical destination and
physical destination modes."
In addition, the local-apic enables cluster mode broadcast. As Intel SDM
10.6.2.2 says: "Broadcast to all local APICs is achieved by setting all
destination bits to one." This patch enables cluster mode broadcast.
The fix tries to combine broadcast in different modes through a unified code.
One rare case occurs when the source of IPI has its APIC disabled. In such
case, the source can still issue IPIs, but since the source is not obliged to
have the same LAPIC mode as the enabled ones, we cannot rely on it.
Since it is a rare case, it is unoptimized and done on the slow-path.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com>
[As per Radim's review, use unsigned int for X2APIC_BROADCAST, return bool from
kvm_apic_broadcast. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CR4.TSD is guest-owned; don't trap writes to it in VMX guests. This
avoids a VM exit on context switches into or out of a PR_TSC_SIGSEGV
task.
I think that this fixes an unintentional side-effect of:
4c38609ac5 KVM: VMX: Make guest cr4 mask more conservative
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the operand size is not 64-bit, then the sysexit instruction should assign
ECX to RSP and EDX to RIP. The current code assigns the full 64-bits.
Fix it by masking.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In 64-bit, stack operations default to 64-bits, but can be overriden (to
16-bit) using opsize override prefix. In contrast, near-branches are always
64-bit. This patch distinguish between the different behaviors.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Breaking grp45 to the relevant functions to speed up the emulation and simplify
the code. In addition, it is necassary the next patch will distinguish between
far and near branches according to the flags.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace the current canonical address check with the new function which is
identical.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"A small set of x86 fixes. The most serious is an SRCU lockdep fix.
A bit late - needed some time to test the SRCU fix, which only came in
on Friday"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: vmx: defer load of APIC access page address during reset
KVM: nVMX: Disable preemption while reading from shadow VMCS
KVM: x86: Fix far-jump to non-canonical check
KVM: emulator: fix execution close to the segment limit
KVM: emulator: fix error code for __linearize
In order to access the shadow VMCS, we need to load it. At this point,
vmx->loaded_vmcs->vmcs and the actually loaded one start to differ. If
we now get preempted by Linux, vmx_vcpu_put and, on return, the
vmx_vcpu_load will work against the wrong vmcs. That can cause
copy_shadow_to_vmcs12 to corrupt the vmcs12 state.
Fix the issue by disabling preemption during the copy operation.
copy_vmcs12_to_shadow is safe from this issue as it is executed by
vmx_vcpu_run when preemption is already disabled before vmentry.
This bug is exposed by running Jailhouse within KVM on CPUs with
shadow VMCS support. Jailhouse never expects an interrupt pending
vmexit, but the bug can cause it if, after copy_shadow_to_vmcs12
is preempted, the active VMCS happens to have the virtual interrupt
pending flag set in the CPU-based execution controls.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit d1442d85cc ("KVM: x86: Handle errors when RIP is set during far
jumps") introduced a bug that caused the fix to be incomplete. Due to
incorrect evaluation, far jump to segment with L bit cleared (i.e., 32-bit
segment) and RIP with any of the high bits set (i.e, RIP[63:32] != 0) set may
not trigger #GP. As we know, this imposes a security problem.
In addition, the condition for two warnings was incorrect.
Fixes: d1442d85cc
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
[Add #ifdef CONFIG_X86_64 to avoid complaints of undefined behavior. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This adds a comment detailing the various intermediate files used to build
the bootable decompression image for the x86 kernel.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Link: http://lkml.kernel.org/r/20141031162204.GA26268@www.outflux.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When choosing a random address, the current implementation does not take into
account the reversed space for .bss and .brk sections. Thus the relocated kernel
may overlap other components in memory. Here is an example of the overlap from a
x86_64 kernel in qemu (the ranges of physical addresses are presented):
Physical Address
0x0fe00000 --+--------------------+ <-- randomized base
/ | relocated kernel |
vmlinux.bin | (from vmlinux.bin) |
0x1336d000 (an ELF file) +--------------------+--
\ | | \
0x1376d870 --+--------------------+ |
| relocs table | |
0x13c1c2a8 +--------------------+ .bss and .brk
| | |
0x13ce6000 +--------------------+ |
| | /
0x13f77000 | initrd |--
| |
0x13fef374 +--------------------+
The initrd image will then be overwritten by the memset during early
initialization:
[ 1.655204] Unpacking initramfs...
[ 1.662831] Initramfs unpacking failed: junk in compressed archive
This patch prevents the above situation by requiring a larger space when looking
for a random kernel base, so that existing logic can effectively avoids the
overlap.
[kees: switched to perl to avoid hex translation pain in mawk vs gawk]
[kees: calculated overlap without relocs table]
Fixes: 82fa9637a2 ("x86, kaslr: Select random position from e820 maps")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Junjie Mao <eternal.n08@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1414762838-13067-1-git-send-email-eternal.n08@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
gcc-4.4.4:
arch/x86/vdso/vma.c: In function 'vgetcpu_cpu_init':
arch/x86/vdso/vma.c:247: error: unknown field 'limit0' specified in initializer
arch/x86/vdso/vma.c:247: warning: missing braces around initializer
arch/x86/vdso/vma.c:247: warning: (near initialization for '(anonymous).<anonymous>')
arch/x86/vdso/vma.c:248: error: unknown field 'limit' specified in initializer
arch/x86/vdso/vma.c:248: warning: excess elements in struct initializer
arch/x86/vdso/vma.c:248: warning: (near initialization for '(anonymous)')
....
I couldn't find any way of tricking it into accepting an initializer
format :(
Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Fixes: 258801563b ("x86/vdso: Change the PER_CPU segment to use struct desc_struct")
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Konrad triggered the following splat below in a 32-bit guest on an AMD
box. As it turns out, in save_microcode_in_initrd_amd() we're using the
*physical* address of the container *after* we have enabled paging and
thus we #PF in load_microcode_amd() when trying to access the microcode
container in the ramdisk range.
Because the ramdisk is exactly there:
[ 0.000000] RAMDISK: [mem 0x35e04000-0x36ef9fff]
and we fault at 0x35e04304.
And since this guest doesn't relocate the ramdisk, we don't do the
computation which will give us the correct virtual address and we end up
with the PA.
So, we should actually be using virtual addresses on 32-bit too by the
time we're freeing the initrd. Do that then!
Unpacking initramfs...
BUG: unable to handle kernel paging request at 35d4e304
IP: [<c042e905>] load_microcode_amd+0x25/0x4a0
*pde = 00000000
Oops: 0000 [#1] SMP
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.17.1-302.fc21.i686 #1
Hardware name: Xen HVM domU, BIOS 4.4.1 10/01/2014
task: f5098000 ti: f50d0000 task.ti: f50d0000
EIP: 0060:[<c042e905>] EFLAGS: 00010246 CPU: 0
EIP is at load_microcode_amd+0x25/0x4a0
EAX: 00000000 EBX: f6e9ec4c ECX: 00001ec4 EDX: 00000000
ESI: f5d4e000 EDI: 35d4e2fc EBP: f50d1ed0 ESP: f50d1e94
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 35d4e304 CR3: 00e33000 CR4: 000406d0
Stack:
00000000 00000000 f50d1ebc f50d1ec4 f5d4e000 c0d7735a f50d1ed0 15a3d17f
f50d1ec4 00600f20 00001ec4 bfb83203 f6e9ec4c f5d4e000 c0d7735a f50d1ed8
c0d80861 f50d1ee0 c0d80429 f50d1ef0 c0d889a9 f5d4e000 c0000000 f50d1f04
Call Trace:
? unpack_to_rootfs
? unpack_to_rootfs
save_microcode_in_initrd_amd
save_microcode_in_initrd
free_initrd_mem
populate_rootfs
? unpack_to_rootfs
do_one_initcall
? unpack_to_rootfs
? repair_env_string
? proc_mkdir
kernel_init_freeable
kernel_init
ret_from_kernel_thread
? rest_init
Reported-and-tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
References: https://bugzilla.redhat.com/show_bug.cgi?id=1158204
Fixes: 75a1ba5b2c ("x86, microcode, AMD: Unify valid container checks")
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # v3.14+
Link: http://lkml.kernel.org/r/20141101100100.GA4462@pd.tnic
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There are some AMD CPU models which have thresholding banks but which
cannot generate a thresholding interrupt. This is denoted by the bit
MCi_MISC[IntP]. Make sure to check that bit before assigning the
thresholding interrupt handler.
Signed-off-by: Chen Yucong <slaoub@gmail.com>
[ Boris: save an indentation level and rewrite commit message. ]
Link: http://lkml.kernel.org/r/1412662128.28440.18.camel@debian
Signed-off-by: Borislav Petkov <bp@suse.de>
Rusty noticed a Really Bad Bug (tm) in my NT fix. The entry code
reads out of bounds, causing the NT fix to be unreliable. But, and
this is much, much worse, if your stack is somehow just below the
top of the direct map (or a hole), you read out of bounds and crash.
Excerpt from the crash:
[ 1.129513] RSP: 0018:ffff88001da4bf88 EFLAGS: 00010296
2b:* f7 84 24 90 00 00 00 testl $0x4000,0x90(%rsp)
That read is deterministically above the top of the stack. I
thought I even single-stepped through this code when I wrote it to
check the offset, but I clearly screwed it up.
Fixes: 8c7aa698ba ("x86_64, entry: Filter RFLAGS.NT on entry from userspace")
Reported-by: Rusty Russell <rusty@ozlabs.org>
Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fixes from Ingo Molnar:
"Fixes from all around the place:
- hyper-V 32-bit PAE guest kernel fix
- two IRQ allocation fixes on certain x86 boards
- intel-mid boot crash fix
- intel-quark quirk
- /proc/interrupts duplicate irq chip name fix
- cma boot crash fix
- syscall audit fix
- boot crash fix with certain TSC configurations (seen on Qemu)
- smpboot.c build warning fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAE
ACPI, irq, x86: Return IRQ instead of GSI in mp_register_gsi()
x86, intel-mid: Create IRQs for APB timers and RTC timers
x86: Don't enable F00F workaround on Intel Quark processors
x86/irq: Fix XT-PIC-XT-PIC in /proc/interrupts
x86, cma: Reserve DMA contiguous area after initmem_init()
i386/audit: stop scribbling on the stack frame
x86, apic: Handle a bad TSC more gracefully
x86: ACPI: Do not translate GSI number if IOAPIC is disabled
x86/smpboot: Move data structure to its primary usage scope
Pull scheduler fixes from Ingo Molnar:
"Various scheduler fixes all over the place: three SCHED_DL fixes,
three sched/numa fixes, two generic race fixes and a comment fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/dl: Fix preemption checks
sched: Update comments for CLONE_NEWNS
sched: stop the unbound recursion in preempt_schedule_context()
sched/fair: Fix division by zero sysctl_numa_balancing_scan_size
sched/fair: Care divide error in update_task_scan_period()
sched/numa: Fix unsafe get_task_struct() in task_numa_assign()
sched/deadline: Fix races between rt_mutex_setprio() and dl_task_timer()
sched/deadline: Don't replenish from a !SCHED_DEADLINE entity
sched: Fix race between task_group and sched_task_group
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, plus on the kernel side:
- a revert for a newly introduced PMU driver which isn't complete yet
and where we ran out of time with fixes (to be tried again in
v3.19) - this makes up for a large chunk of the diffstat.
- compilation warning fixes
- a printk message fix
- event_idx usage fixes/cleanups"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf probe: Trivial typo fix for --demangle
perf tools: Fix report -F dso_from for data without branch info
perf tools: Fix report -F dso_to for data without branch info
perf tools: Fix report -F symbol_from for data without branch info
perf tools: Fix report -F symbol_to for data without branch info
perf tools: Fix report -F mispredict for data without branch info
perf tools: Fix report -F in_tx for data without branch info
perf tools: Fix report -F abort for data without branch info
perf tools: Make CPUINFO_PROC an array to support different kernel versions
perf callchain: Use global caching provided by libunwind
perf/x86/intel: Revert incomplete and undocumented Broadwell client support
perf/x86: Fix compile warnings for intel_uncore
perf: Fix typos in sample code in the perf_event.h header
perf: Fix and clean up initialization of pmu::event_idx
perf: Fix bogus kernel printk
perf diff: Add missing hists__init() call at tool start
The file /sys/kernel/debug/tracing/eneabled_functions is used to debug
ftrace function hooks. Add to the output what function is being called
by the trampoline if the arch supports it.
Add support for this feature in x86_64.
Cc: H. Peter Anvin <hpa@linux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The current method of handling multiple function callbacks is to register
a list function callback that calls all the other callbacks based on
their hash tables and compare it to the function that the callback was
called on. But this is very inefficient.
For example, if you are tracing all functions in the kernel and then
add a kprobe to a function such that the kprobe uses ftrace, the
mcount trampoline will switch from calling the function trace callback
to calling the list callback that will iterate over all registered
ftrace_ops (in this case, the function tracer and the kprobes callback).
That means for every function being traced it checks the hash of the
ftrace_ops for function tracing and kprobes, even though the kprobes
is only set at a single function. The kprobes ftrace_ops is checked
for every function being traced!
Instead of calling the list function for functions that are only being
traced by a single callback, we can call a dynamically allocated
trampoline that calls the callback directly. The function graph tracer
already uses a direct call trampoline when it is being traced by itself
but it is not dynamically allocated. It's trampoline is static in the
kernel core. The infrastructure that called the function graph trampoline
can also be used to call a dynamically allocated one.
For now, only ftrace_ops that are not dynamically allocated can have
a trampoline. That is, users such as function tracer or stack tracer.
kprobes and perf allocate their ftrace_ops, and until there's a safe
way to free the trampoline, it can not be used. The dynamically allocated
ftrace_ops may, although, use the trampoline if the kernel is not
compiled with CONFIG_PREEMPT. But that will come later.
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In order to access the shadow VMCS, we need to load it. At this point,
vmx->loaded_vmcs->vmcs and the actually loaded one start to differ. If
we now get preempted by Linux, vmx_vcpu_put and, on return, the
vmx_vcpu_load will work against the wrong vmcs. That can cause
copy_shadow_to_vmcs12 to corrupt the vmcs12 state.
Fix the issue by disabling preemption during the copy operation.
copy_vmcs12_to_shadow is safe from this issue as it is executed by
vmx_vcpu_run when preemption is already disabled before vmentry.
This bug is exposed by running Jailhouse within KVM on CPUs with
shadow VMCS support. Jailhouse never expects an interrupt pending
vmexit, but the bug can cause it if, after copy_shadow_to_vmcs12
is preempted, the active VMCS happens to have the virtual interrupt
pending flag set in the CPU-based execution controls.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit d1442d85cc ("KVM: x86: Handle errors when RIP is set during far
jumps") introduced a bug that caused the fix to be incomplete. Due to
incorrect evaluation, far jump to segment with L bit cleared (i.e., 32-bit
segment) and RIP with any of the high bits set (i.e, RIP[63:32] != 0) set may
not trigger #GP. As we know, this imposes a security problem.
In addition, the condition for two warnings was incorrect.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
[Add #ifdef CONFIG_X86_64 to avoid complaints of undefined behavior. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Emulation of code that is 14 bytes to the segment limit or closer
(e.g. RIP = 0xFFFFFFF2 after reset) is broken because we try to read as
many as 15 bytes from the beginning of the instruction, and __linearize
fails when the passed (address, size) pair reaches out of the segment.
To fix this, let __linearize return the maximum accessible size (clamped
to 2^32-1) for usage in __do_insn_fetch_bytes, and avoid the limit check
by passing zero for the desired size.
For expand-down segments, __linearize is performing a redundant check.
(u32)(addr.ea + size - 1) <= lim can only happen if addr.ea is close
to 4GB; in this case, addr.ea + size - 1 will also fail the check against
the upper bound of the segment (which is provided by the D/B bit).
After eliminating the redundant check, it is simple to compute
the *max_size for expand-down segments too.
Now that the limit check is done in __do_insn_fetch_bytes, we want
to inject a general protection fault there if size < op_size (like
__linearize would have done), instead of just aborting.
This fixes booting Tiano Core from emulated flash with EPT disabled.
Cc: stable@vger.kernel.org
Fixes: 719d5a9b24
Reported-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The error code for #GP and #SS is zero when the segment is used to
access an operand or an instruction. It is only non-zero when
a segment register is being loaded; for limit checks this means
cases such as:
* for #GP, when RIP is beyond the limit on a far call (before the first
instruction is executed). We do not implement this check, but it
would be in em_jmp_far/em_call_far.
* for #SS, if the new stack overflows during an inter-privilege-level
call to a non-conforming code segment. We do not implement stack
switching at all.
So use an error code of zero.
Reviewed-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These patches:
86a349a28b ("perf/x86/intel: Add Broadwell core support")
c46e665f03 ("perf/x86: Add INST_RETIRED.ALL workarounds")
fdda3c4aac ("perf/x86/intel: Use Broadwell cache event list for Haswell")
introduced magic constants and unexplained changes:
https://lkml.org/lkml/2014/10/28/1128https://lkml.org/lkml/2014/10/27/325https://lkml.org/lkml/2014/8/27/546https://lkml.org/lkml/2014/10/28/546
Peter Zijlstra has attempted to help out, to clean up the mess:
https://lkml.org/lkml/2014/10/28/543
But has not received helpful and constructive replies which makes
me doubt wether it can all be finished in time until v3.18 is
released.
Despite various review feedback the author (Andi Kleen) has answered
only few of the review questions and has generally been uncooperative,
only giving replies when prompted repeatedly, and only giving minimal
answers instead of constructively explaining and helping along the effort.
That kind of behavior is not acceptable.
There's also a boot crash on Intel E5-1630 v3 CPUs reported for another
commit from Andi Kleen:
e735b9db12 ("perf/x86/intel/uncore: Add Haswell-EP uncore support")
https://lkml.org/lkml/2014/10/22/730
Which is not yet resolved. The uncore driver is independent in theory,
but the crash makes me worry about how well all these patches were
tested and makes me uneasy about the level of interminging that the
Broadwell and Haswell code has received by the commits above.
As a first step to resolve the mess revert the Broadwell client commits
back to the v3.17 version, before we run out of time and problematic
code hits a stable upstream kernel.
( If the Haswell-EP crash is not resolved via a simple fix then we'll have
to revert the Haswell-EP uncore driver as well. )
The Broadwell client series has to be submitted in a clean fashion, with
single, well documented changes per patch. If they are submitted in time
and are accepted during review then they can possibly go into v3.19 but
will need additional scrutiny due to the rocky history of this patch set.
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1409683455-29168-3-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long <<
PAGE_SHIFT" will overflow for PFNs above 4GB.
Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V,
with 5GB memory assigned, can't load the netvsc driver successfully and
hence the synthetic network device can't work (we can use the kernel parameter
mem=3000M to work around the issue).
Cast pte_pfn() to phys_addr_t before shifting.
Fixes: "commit d76565344512: x86, mm: Create slow_virt_to_phys()"
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: gregkh@linuxfoundation.org
Cc: linux-mm@kvack.org
Cc: olaf@aepfle.de
Cc: apw@canonical.com
Cc: jasowang@redhat.com
Cc: dave.hansen@intel.com
Cc: riel@redhat.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1414580017-27444-1-git-send-email-decui@microsoft.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Function mp_register_gsi() returns blindly the GSI number for the ACPI
SCI interrupt. That causes a regression when the GSI for ACPI SCI is
shared with other devices.
The regression was caused by commit 84245af729 "x86, irq, ACPI:
Change __acpi_register_gsi to return IRQ number instead of GSI" and
exposed on a SuperMicro system, which shares one GSI between ACPI SCI
and PCI device, with following failure:
http://sourceforge.net/p/linux1394/mailman/linux1394-user/?viewmonth=201410
[ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low
level)
[ 2.699224] firewire_ohci 0000:06:00.0: failed to allocate interrupt
20
Return mp_map_gsi_to_irq(gsi, 0) instead of the GSI number.
Reported-and-Tested-by: Daniel Robbins <drobbins@funtoo.org>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: <stable@vger.kernel.org> # 3.17
Link: http://lkml.kernel.org/r/1414387308-27148-4-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Intel MID platforms has no legacy interrupts, so no IRQ descriptors
preallocated. We need to call mp_map_gsi_to_irq() to create IRQ
descriptors for APB timers and RTC timers, otherwise it may cause
invalid memory access as:
[ 0.116839] BUG: unable to handle kernel NULL pointer dereference at
0000003a
[ 0.123803] IP: [<c1071c0e>] setup_irq+0xf/0x4d
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Cohen <david.a.cohen@linux.intel.com>
Cc: <stable@vger.kernel.org> # 3.17
Link: http://lkml.kernel.org/r/1414387308-27148-3-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Intel Quark processor is a part of family 5, but does not have the
F00F bug present in Pentiums of the same family.
Pentiums were models 0 through 8, Quark is model 9.
Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Link: http://lkml.kernel.org/r/20141028175753.GA12743@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It is a problem when configuring high memory off where the
vmalloc reserve area could end up overlapping the early_ioremap
fixmap area on i386.
The ordering of the VMALLOC_RESERVE space is:
FIXADDR_TOP
fixed_addresses
FIXADDR_START
early_ioremap fixed addresses
FIXADDR_BOOT_START
Persistent kmap area
PKMAP_BASE
VMALLOC_END
Vmalloc area
VMALLOC_START
high_memory
The available address we can use is lower than
FIXADDR_BOOT_START. So we will set the kmap boundary below the
FIXADDR_BOOT_START, if we configure high memory.
If we configure high memory, the vmalloc reserve area should
end up to PKMAP_BASE, otherwise should end up to
FIXADDR_BOOT_START.
Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/6B680A9E-6CE9-4C96-934B-CB01DCB58278@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix duplicate XT-PIC seen in /proc/interrupts on x86 systems
that make use of 8259A Programmable Interrupt Controllers.
Specifically convert output like this:
CPU0
0: 76573 XT-PIC-XT-PIC timer
1: 11 XT-PIC-XT-PIC i8042
2: 0 XT-PIC-XT-PIC cascade
4: 8 XT-PIC-XT-PIC serial
6: 3 XT-PIC-XT-PIC floppy
7: 0 XT-PIC-XT-PIC parport0
8: 1 XT-PIC-XT-PIC rtc0
10: 448 XT-PIC-XT-PIC fddi0
12: 23 XT-PIC-XT-PIC eth0
14: 2464 XT-PIC-XT-PIC ide0
NMI: 0 Non-maskable interrupts
ERR: 0
to one like this:
CPU0
0: 122033 XT-PIC timer
1: 11 XT-PIC i8042
2: 0 XT-PIC cascade
4: 8 XT-PIC serial
6: 3 XT-PIC floppy
7: 0 XT-PIC parport0
8: 1 XT-PIC rtc0
10: 145 XT-PIC fddi0
12: 31 XT-PIC eth0
14: 2245 XT-PIC ide0
NMI: 0 Non-maskable interrupts
ERR: 0
that is one like we used to have from ~2.2 till it was changed
sometime.
The rationale is there is no value in this duplicate
information, it merely clutters output and looks ugly. We only
have one handler for 8259A interrupts so there is no need to
give it a name separate from the name already given to
irq_chip.
We could define meaningful names for handlers based on bits in
the ELCR register on systems that have it or the value of the
LTIM bit we use in ICW1 otherwise (hardcoded to 0 though with
MCA support gone), to tell edge-triggered and level-triggered
inputs apart. While that information does not affect 8259A
interrupt handlers it could help people determine which lines
are shareable and which are not. That is material for a
separate change though.
Any tools that parse /proc/interrupts are supposed not to be
affected since it was many years we used the format this change
converts back to.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1410260147190.21390@eddie.linux-mips.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Drop double entry for pt_regs_bx.
This seems to be a typo - resulting in a double entry in the
generated include/generated/asm-offsets.h, which is not necessary.
Build-tested and booted on x86 64 box to make sure it was not
doing any strange magic.... after all it was in the kernel in
this form for almost 10 years.
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141027172805.GA19760@opentech.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
IMO users ought not to be able to use 16-bit segments without
using modify_ldt. Fortunately, it's impossible to break
espfix64 by loading the PER_CPU segment into SS because it's
PER_CPU is marked read-only and SS cannot contain an RO segment,
but marking PER_CPU as 32-bit is less fragile.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/179f490d659307873eefd09206bebd417e2ab5ad.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The first userspace attempt to read or write the PER_CPU segment
will write the accessed bit to the GDT. This is visible to
userspace using the LAR instruction, and it also pointlessly
dirties a cache line.
Set the segment's accessed bit at boot to prevent userspace
access to segments from having side effects.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/ac63814ca4c637a08ec2fd0360d67ca67560a9ee.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The code is correct, but only for a rather subtle reason. This
confused me for quite a while when I read switch_mm, so clarify
the code to avoid confusing other people, too.
TBH, I wouldn't be surprised if this code was only correct by
accident.
[ I wouldn't normally send a comment-only patch, but it took me a long
time to first figure out wtf was going on here, and then to figure
out why this wasn't exploitable by malicious code, and then to
figure out why this oddity had no user-visible effect at all. Let's
spare future readers the same confusion. ]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/36275c99801a87d8dcf0502a41cf4e2ad81aae46.1412623954.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that the kernel always runs with clean flags (in particular,
NT is clear), there is no need to save and restore flags on
every context switch.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Sebastian Lackner <sebastian@fds-team.de>
Cc: Anish Bhatt <anish@chelsio.com>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/bf6fb790787eb95b922157838f52712c25dda157.1412187233.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy spotted the fail in what was intended as a conditional printk level.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Fixes: cc6cd47e73 ("perf/x86: Tone down kernel messages when the PMU check fails in a virtual environment")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141007124757.GH19379@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
task_preempt_count() is pointless if preemption counter is per-cpu,
currently this is x86 only. It is only valid if the task is not
running, and even in this case the only info it can provide is the
state of PREEMPT_ACTIVE bit.
Change its single caller to check p->on_rq instead, this should be
the same if p->state != TASK_RUNNING, and kill this helper.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/20141008183348.GC17495@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
preempt_schedule_context() does preempt_enable_notrace() at the end
and this can call the same function again; exception_exit() is heavy
and it is quite possible that need-resched is true again.
1. Change this code to dec preempt_count() and check need_resched()
by hand.
2. As Linus suggested, we can use the PREEMPT_ACTIVE bit and avoid
the enable/disable dance around __schedule(). But in this case
we need to move into sched/core.c.
3. Cosmetic, but x86 forgets to declare this function. This doesn't
really matter because it is only called by asm helpers, still it
make sense to add the declaration into asm/preempt.h to match
preempt_schedule().
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20141005202322.GB27962@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fengguang Wu reported a boot crash on the x86 platform
via the 0-day Linux Kernel Performance Test:
cma: dma_contiguous_reserve: reserving 31 MiB for global area
BUG: Int 6: CR2 (null)
[<41850786>] dump_stack+0x16/0x18
[<41d2b1db>] early_idt_handler+0x6b/0x6b
[<41072227>] ? __phys_addr+0x2e/0xca
[<41d4ee4d>] cma_declare_contiguous+0x3c/0x2d7
[<41d6d359>] dma_contiguous_reserve_area+0x27/0x47
[<41d6d4d1>] dma_contiguous_reserve+0x158/0x163
[<41d33e0f>] setup_arch+0x79b/0xc68
[<41d2b7cf>] start_kernel+0x9c/0x456
[<41d2b2ca>] i386_start_kernel+0x79/0x7d
(See details at: https://lkml.org/lkml/2014/10/8/708)
It is because dma_contiguous_reserve() is called before
initmem_init() in x86, the variable high_memory is not
initialized but accessed by __pa(high_memory) in
dma_contiguous_reserve().
This patch moves dma_contiguous_reserve() after initmem_init()
so that high_memory is initialized before accessed.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: iamjoonsoo.kim@lge.com
Cc: 'Linux-MM' <linux-mm@kvack.org>
Cc: 'Weijie Yang' <weijie.yang.kh@gmail.com>
Link: http://lkml.kernel.org/r/000101cfef69%2431e528a0%2495af79e0%24%25yang@samsung.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ok, new attempt, this time around with full ppgtt disabled again.
drm-intel-next-2014-10-03:
- first batch of skl stage 1 enabling
- fixes from Rodrigo to the PSR, fbc and sink crc code
- kerneldoc for the frontbuffer tracking code, runtime pm code and the basic
interrupt enable/disable functions
- smaller stuff all over
drm-intel-next-2014-09-19:
- bunch more i830M fixes from Ville
- full ppgtt now again enabled by default
- more ppgtt fixes from Michel Thierry and Chris Wilson
- plane config work from Gustavo Padovan
- spinlock clarifications
- piles of smaller improvements all over, as usual
* tag 'drm-intel-next-2014-10-03-no-ppgtt' of git://anongit.freedesktop.org/drm-intel: (114 commits)
Revert "drm/i915: Enable full PPGTT on gen7"
drm/i915: Update DRIVER_DATE to 20141003
drm/i915: Remove the duplicated logic between the two shrink phases
drm/i915: kerneldoc for interrupt enable/disable functions
drm/i915: Use dev_priv instead of dev in irq setup functions
drm/i915: s/pm._irqs_disabled/pm.irqs_enabled/
drm/i915: Clear TX FIFO reset master override bits on chv
drm/i915: Make sure hardware uses the correct swing margin/deemph bits on chv
drm/i915: make sink_crc return -EIO on aux read/write failure
drm/i915: Constify send buffer for intel_dp_aux_ch
drm/i915: De-magic the PSR AUX message
drm/i915: Reinstate error level message for non-simulated gpu hangs
drm/i915: Kerneldoc for intel_runtime_pm.c
drm/i915: Call runtime_pm_disable directly
drm/i915: Move intel_display_set_init_power to intel_runtime_pm.c
drm/i915: Bikeshed rpm functions name a bit.
drm/i915: Extract intel_runtime_pm.c
drm/i915: Remove intel_modeset_suspend_hw
drm/i915: spelling fixes for frontbuffer tracking kerneldoc
drm/i915: Tighting frontbuffer tracking around flips
...
To query resources in ACPI systems we need to define a data structure. This
would be set as platform_info for the devices.
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This will be used to abstract the differances in ipc offsets for different
chips.
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
git commit b4f0d3755c was very very dumb.
It was writing over %esp/pt_regs semi-randomly on i686 with the expected
"system can't boot" results. As noted in:
https://bugs.freedesktop.org/show_bug.cgi?id=85277
This patch stops fscking with pt_regs. Instead it sets up the registers
for the call to __audit_syscall_entry in the most obvious conceivable
way. It then does just a tiny tiny touch of magic. We need to get what
started in PT_EDX into 0(%esp) and PT_ESI into 4(%esp). This is as easy
as a pair of pushes.
After the call to __audit_syscall_entry all we need to do is get that
now useless junk off the stack (pair of pops) and reload %eax with the
original syscall so other stuff can keep going about it's business.
Reported-by: Paulo Zanoni <przanoni@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Link: http://lkml.kernel.org/r/1414037043-30647-1-git-send-email-eparis@redhat.com
Cc: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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Merge tag 'v3.18-rc1' into x86/urgent
Reason:
Need to apply audit patch on top of v3.18-rc1.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
as what I usually had for the _whole_ rc period.
There are a few bad bugs where the guest can OOPS or crash the host. We
have also started looking at attack models for nested virtualization;
bugs that usually result in the guest ring 0 crashing itself become
more worrisome if you have nested virtualization, because the nested
guest might bring down the non-nested guest as well. For current
uses of nested virtualization these do not really have a security
impact, but you never know and bugs are bugs nevertheless.
A lot of these bugs are in 3.17 too, resulting in a large number of
stable@ Ccs. I checked that all the patches apply there with no
conflicts.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"This is a pretty large update. I think it is roughly as big as what I
usually had for the _whole_ rc period.
There are a few bad bugs where the guest can OOPS or crash the host.
We have also started looking at attack models for nested
virtualization; bugs that usually result in the guest ring 0 crashing
itself become more worrisome if you have nested virtualization,
because the nested guest might bring down the non-nested guest as
well. For current uses of nested virtualization these do not really
have a security impact, but you never know and bugs are bugs
nevertheless.
A lot of these bugs are in 3.17 too, resulting in a large number of
stable@ Ccs. I checked that all the patches apply there with no
conflicts"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: vfio: fix unregister kvm_device_ops of vfio
KVM: x86: Wrong assertion on paging_tmpl.h
kvm: fix excessive pages un-pinning in kvm_iommu_map error path.
KVM: x86: PREFETCH and HINT_NOP should have SrcMem flag
KVM: x86: Emulator does not decode clflush well
KVM: emulate: avoid accessing NULL ctxt->memopp
KVM: x86: Decoding guest instructions which cross page boundary may fail
kvm: x86: don't kill guest on unknown exit reason
kvm: vmx: handle invvpid vm exit gracefully
KVM: x86: Handle errors when RIP is set during far jumps
KVM: x86: Emulator fixes for eip canonical checks on near branches
KVM: x86: Fix wrong masking on relative jump/call
KVM: x86: Improve thread safety in pit
KVM: x86: Prevent host from panicking on shared MSR writes.
KVM: x86: Check non-canonical addresses upon WRMSR
- Fix regression in xen_clocksource_read() which caused all Xen guests
to crash early in boot.
- Several fixes for super rare race conditions in the p2m.
- Assorted other minor fixes.
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Merge tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen bug fixes from David Vrabel:
- Fix regression in xen_clocksource_read() which caused all Xen guests
to crash early in boot.
- Several fixes for super rare race conditions in the p2m.
- Assorted other minor fixes.
* tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pci: Allocate memory for physdev_pci_device_add's optarr
x86/xen: panic on bad Xen-provided memory map
x86/xen: Fix incorrect per_cpu accessor in xen_clocksource_read()
x86/xen: avoid race in p2m handling
x86/xen: delay construction of mfn_list_list
x86/xen: avoid writing to freed memory after race in p2m handling
xen/balloon: Don't continue ballooning when BP_ECANCELED is encountered
Even after the recent fix, the assertion on paging_tmpl.h is triggered.
Apparently, the assertion wants to check that the PAE is always set on
long-mode, but does it in incorrect way. Note that the assertion is not
enabled unless the code is debugged by defining MMU_DEBUG.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The decode phase of the x86 emulator assumes that every instruction with the
ModRM flag, and which can be used with RIP-relative addressing, has either
SrcMem or DstMem. This is not the case for several instructions - prefetch,
hint-nop and clflush.
Adding SrcMem|NoAccess for prefetch and hint-nop and SrcMem for clflush.
This fixes CVE-2014-8480.
Fixes: 41061cdb98
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, all group15 instructions are decoded as clflush (e.g., mfence,
xsave). In addition, the clflush instruction requires no prefix (66/f2/f3)
would exist. If prefix exists it may encode a different instruction (e.g.,
clflushopt).
Creating a group for clflush, and different group for each prefix.
This has been the case forever, but the next patch needs the cflush group
in order to fix a bug introduced in 3.17.
Fixes: 41061cdb98
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A failure to decode the instruction can cause a NULL pointer access.
This is fixed simply by moving the "done" label as close as possible
to the return.
This fixes CVE-2014-8481.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Cc: stable@vger.kernel.org
Fixes: 41061cdb98
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Once an instruction crosses a page boundary, the size read from the second page
disregards the common case that part of the operand resides on the first page.
As a result, fetch of long insturctions may fail, and thereby cause the
decoding to fail as well.
Cc: stable@vger.kernel.org
Fixes: 5cfc7e0f5e
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_EXIT_UNKNOWN is a kvm bug, we don't really know whether it was
triggered by a priveledged application. Let's not kill the guest: WARN
and inject #UD instead.
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On systems with invvpid instruction support (corresponding bit in
IA32_VMX_EPT_VPID_CAP MSR is set) guest invocation of invvpid
causes vm exit, which is currently not handled and results in
propagation of unknown exit to userspace.
Fix this by installing an invvpid vm exit handler.
This is CVE-2014-3646.
Cc: stable@vger.kernel.org
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Far jmp/call/ret may fault while loading a new RIP. Currently KVM does not
handle this case, and may result in failed vm-entry once the assignment is
done. The tricky part of doing so is that loading the new CS affects the
VMCS/VMCB state, so if we fail during loading the new RIP, we are left in
unconsistent state. Therefore, this patch saves on 64-bit the old CS
descriptor and restores it if loading RIP failed.
This fixes CVE-2014-3647.
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before changing rip (during jmp, call, ret, etc.) the target should be asserted
to be canonical one, as real CPUs do. During sysret, both target rsp and rip
should be canonical. If any of these values is noncanonical, a #GP exception
should occur. The exception to this rule are syscall and sysenter instructions
in which the assigned rip is checked during the assignment to the relevant
MSRs.
This patch fixes the emulator to behave as real CPUs do for near branches.
Far branches are handled by the next patch.
This fixes CVE-2014-3647.
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Relative jumps and calls do the masking according to the operand size, and not
according to the address size as the KVM emulator does today.
This patch fixes KVM behavior.
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There's a race condition in the PIT emulation code in KVM. In
__kvm_migrate_pit_timer the pit_timer object is accessed without
synchronization. If the race condition occurs at the wrong time this
can crash the host kernel.
This fixes CVE-2014-3611.
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The previous patch blocked invalid writes directly when the MSR
is written. As a precaution, prevent future similar mistakes by
gracefulling handle GPs caused by writes to shared MSRs.
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
[Remove parts obsoleted by Nadav's patch. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Upon WRMSR, the CPU should inject #GP if a non-canonical value (address) is
written to certain MSRs. The behavior is "almost" identical for AMD and Intel
(ignoring MSRs that are not implemented in either architecture since they would
anyhow #GP). However, IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if
non-canonical address is written on Intel but not on AMD (which ignores the top
32-bits).
Accordingly, this patch injects a #GP on the MSRs which behave identically on
Intel and AMD. To eliminate the differences between the architecutres, the
value which is written to IA32_SYSENTER_ESP and IA32_SYSENTER_EIP is turned to
canonical value before writing instead of injecting a #GP.
Some references from Intel and AMD manuals:
According to Intel SDM description of WRMSR instruction #GP is expected on
WRMSR "If the source register contains a non-canonical address and ECX
specifies one of the following MSRs: IA32_DS_AREA, IA32_FS_BASE, IA32_GS_BASE,
IA32_KERNEL_GS_BASE, IA32_LSTAR, IA32_SYSENTER_EIP, IA32_SYSENTER_ESP."
According to AMD manual instruction manual:
LSTAR/CSTAR (SYSCALL): "The WRMSR instruction loads the target RIP into the
LSTAR and CSTAR registers. If an RIP written by WRMSR is not in canonical
form, a general-protection exception (#GP) occurs."
IA32_GS_BASE and IA32_FS_BASE (WRFSBASE/WRGSBASE): "The address written to the
base field must be in canonical form or a #GP fault will occur."
IA32_KERNEL_GS_BASE (SWAPGS): "The address stored in the KernelGSbase MSR must
be in canonical form."
This patch fixes CVE-2014-3610.
Cc: stable@vger.kernel.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Steven Rostedt (Red Hat)