Rather than trying to deal with aliases once they appear, just completely
inhibit them. Mostly the removal of aliases was managable, but it comes
unstuck in xen_create_contiguous_region() because it gets executed at
interrupt time (as a result of dma_alloc_coherent()), which causes all
sorts of confusion in the vmap code, as it was never intended to be run
in interrupt context.
This has the unfortunate side effect of removing all the unmap batching
the vmap code so carefully added, but that can't be helped.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
A memory region must be physically contiguous in order to be accessed
through DMA. This patch adds xen_create_contiguous_region, which
ensures a region of contiguous virtual memory is also physically
contiguous.
Based on Stephen Tweedie's port of the 2.6.18-xen version.
Remove contiguous_bitmap[] as it's no longer needed.
Ported from linux-2.6.18-xen.hg 707:e410857fd83c
[ Impact: add Xen-internal API to make pages phys-contig ]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen_create_contiguous_region needs access to the balloon lock to
ensure memory doesn't change under its feet, so expose the balloon
lock
* Change the name of the lock to xen_reservation_lock, to imply it's
now less-specific usage.
[ Impact: cleanup ]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
PV DomU domains are allowed to map hardware MFNs for PCI passthrough,
but are not generally allowed to map raw machine pages. In particular,
various pieces of code try to map DMI and ACPI tables in the ISA ROM
range. We disallow _PAGE_IOMAP for those mappings, so that they are
redirected to a set of local zeroed pages we reserve for that purpose.
[ Impact: prevent passthrough of ISA space, as we only allow PCI ]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In a Xen domain, ioremap operates on machine addresses, not
pseudo-physical addresses. We use _PAGE_IOMAP to determine whether a
mapping is intended for machine addresses.
[ Impact: allow Xen domain to map real hardware ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Do not blindly access extended configuration space unless we actively
know we're on a Moorestown platform. The fixed-size BAR capability
lives in the extended configuration space, and thus is not applicable
if the configuration space isn't appropriately sized.
This fixes booting certain VMware configurations with CONFIG_MRST=y.
Moorestown will add a fake PCI-X 266 capability to advertise the
presence of extended configuration space.
Reported-and-tested-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Jacob Pan <jacob.jun.pan@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <AANLkTiltKUa3TrKR1M51eGw8FLNoQJSLT0k0_K5X3-OJ@mail.gmail.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, cacheinfo: Turn off L3 cache index disable feature in virtualized environments
x86, k8: Fix build error when K8_NB is disabled
x86, amd: Check X86_FEATURE_OSVW bit before accessing OSVW MSRs
x86: Fix fake apicid to node mapping for numa emulation
K8_NB depends on PCI and when the last is disabled (allnoconfig) we fail
at the final linking stage due to missing exported num_k8_northbridges.
Add a header stub for that.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100503183036.GJ26107@aftab>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
If host CPU is exposed to a guest the OSVW MSRs are not guaranteed
to be present and a GP fault occurs. Thus checking the feature flag is
essential.
Cc: <stable@kernel.org> # .32.x .33.x
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100427101348.GC4489@alberich.amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
As the processor may not consider GUEST_INTR_STATE_STI as a reason for
blocking NMI, it could return immediately with EXIT_REASON_NMI_WINDOW
when we asked for it. But as we consider this state as NMI-blocking, we
can run into an endless loop.
Resolve this by allowing NMI injection if just GUEST_INTR_STATE_STI is
active (originally suggested by Gleb). Intel confirmed that this is
safe, the processor will never complain about NMI injection in this
state.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
KVM-Stable-Tag
Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
cpuid_update may operate VMCS, so vcpu_load() and vcpu_put()
should be called to ensure correctness.
Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch makes KVM on 32 bit SVM working again by
correcting the masks used for iret interception. With the
wrong masks the upper 32 bits of the intercepts are masked
out which leaves vmrun unintercepted. This is not legal on
svm and the vmrun fails.
Bug was introduced by commits 95ba827313 and 3cfc3092.
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Fix kprobe/x86 to check removed int3 when failing to get kprobe
from hlist. Since we have a time window between checking int3
exists on probed address and getting kprobe on that address,
we can have following scenario:
-------
CPU1 CPU2
hit int3
check int3 exists
remove int3
remove kprobe from hlist
get kprobe from hlist
no kprobe->OOPS!
-------
This patch moves int3 checking if there is no kprobe on that
address for fixing this problem as follows:
------
CPU1 CPU2
hit int3
remove int3
remove kprobe from hlist
get kprobe from hlist
no kprobe->check int3 exists
->rollback&retry
------
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100427223348.2322.9112.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With NUMA emulation, it's possible for a single cpu to be bound
to multiple nodes since more than one may have affinity if
allocated on a physical node that is local to the cpu.
APIC ids must therefore be mapped to the lowest node ids to
maintain generic kernel use of functions such as cpu_to_node()
that determine device affinity. For example, if a device has
proximity to physical node 1, for instance, and a cpu happens to
be mapped to a higher emulated node id 8, the proximity may not
be correctly determined by comparison in generic code even
though the cpu may be truly local and allocated on physical node 1.
When this happens, the true topology of the machine isn't
accurately represented in the emulated environment; although
this isn't critical to the system's uptime, any generic code
that is NUMA aware benefits from the physical topology being
accurately represented.
This can affect any system that maps multiple APIC ids to a
single node and is booted with numa=fake=N where N is greater
than the number of physical nodes.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <alpine.DEB.2.00.1005060224140.19473@chino.kir.corp.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
powernow-k8: Fix frequency reporting
x86: Fix parse_reservetop() build failure on certain configs
x86: Fix NULL pointer access in irq_force_complete_move() for Xen guests
x86: Fix 'reservetop=' functionality
The x86_64 call_rwsem_wait() treats the active state counter part of the
R/W semaphore state as being 16-bit when it's actually 32-bit (it's half
of the 64-bit state). It should do "decl %edx" not "decw %dx".
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With F10, model 10, all valid frequencies are in the ACPI _PST table.
Cc: <stable@kernel.org> # 33.x 32.x
Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
LKML-Reference: <1270065406-1814-6-git-send-email-bp@amd64.org>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Reviewed-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit e67a807 ("x86: Fix 'reservetop=' functionality") added a
fixup_early_ioremap() call to parse_reservetop() and declared it
in io.h.
But asm/io.h was only included indirectly - and on some configs
not at all, causing a build failure on those configs.
Cc: Liang Li <liang.li@windriver.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Wang Chen <wangchen@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1272621711-8683-1-git-send-email-liang.li@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Upstream PV guests fail to boot because of a NULL pointer in
irq_force_complete_move(). It is possible that xen guests have
irq_desc->chip_data = NULL.
Test for NULL chip_data pointer before attempting to complete an irq move.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
LKML-Reference: <20100427152434.16193.49104.sendpatchset@prarit.bos.redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org> [2.6.33]
When specifying the 'reservetop=0xbadc0de' kernel parameter,
the kernel will stop booting due to a early_ioremap bug that
relates to commit 8827247ff.
The root cause of boot failure problem is the value of
'slot_virt[i]' was initialized in setup_arch->early_ioremap_init().
But later in setup_arch, the function 'parse_early_param' will
modify 'FIXADDR_TOP' when 'reservetop=0xbadc0de' being specified.
The simplest fix might be use __fix_to_virt(idx0) to get updated
value of 'FIXADDR_TOP' in '__early_ioremap' instead of reference
old value from slot_virt[slot] directly.
Changelog since v0:
-v1: When reservetop being handled then FIXADDR_TOP get
adjusted, Hence check prev_map then re-initialize slot_virt and
PMD based on new FIXADDR_TOP.
-v2: place fixup_early_ioremap hence call early_ioremap_init in
reserve_top_address to re-initialize slot_virt and
corresponding PMD when parse_reservertop
-v3: move fixup_early_ioremap out of reserve_top_address to make
sure other clients of reserve_top_address like xen/lguest won't
broken
Signed-off-by: Liang Li <liang.li@windriver.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Wang Chen <wangchen@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1272621711-8683-1-git-send-email-liang.li@windriver.com>
[ fixed three small cleanliness details in fixup_early_ioremap() ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
x86: Disable large pages on CPUs with Atom erratum AAE44
x86-64: Clear a 64-bit FS/GS base on fork if selector is nonzero
x86, mrst: Conditionally register cpu hotplug notifier for apbt
ACPI _CRS Address Space Descriptors have _MIN, _MAX, and _LEN. Linux has
been computing Address Spaces as [_MIN to _MIN + _LEN - 1]. Based on the
tests in the bug reports below, Windows apparently uses [_MIN to _MAX].
Per spec (ACPI 4.0, Table 6-40), for _CRS fixed-size, fixed location
descriptors, "_LEN must be (_MAX - _MIN + 1)", and when that's true, it
doesn't matter which way we compute the end. But of course, there are
BIOSes that don't follow this rule, and we're better off if Linux handles
those exceptions the same way as Windows.
This patch makes Linux use [_MIN to _MAX], as Windows seems to do. This
effectively reverts d558b483d5 and 03db42adfe and replaces them with
simpler code.
https://bugzilla.kernel.org/show_bug.cgi?id=14337 (round)
https://bugzilla.kernel.org/show_bug.cgi?id=15480 (truncate)
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
When we move a PCI device or assign resources to a device not configured
by the BIOS, we want to avoid the BIOS region below 1MB. Note that if the
BIOS places devices below 1MB, we leave them there.
See https://bugzilla.kernel.org/show_bug.cgi?id=15744
and https://bugzilla.kernel.org/show_bug.cgi?id=15841
Tested-by: Andy Isaacson <adi@hexapodia.org>
Tested-by: Andy Bailey <bailey@akamai.com>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: Ensure we re-enable devices on resume
x86/PCI: parse additional host bridge window resource types
PCI: revert broken device warning
PCI aerdrv: use correct bit defines and add 2ms delay to aer_root_reset
x86/PCI: ignore Consumer/Producer bit in ACPI window descriptions
This is a standalone version of VMware Balloon driver. Ballooning is a
technique that allows hypervisor dynamically limit the amount of memory
available to the guest (with guest cooperation). In the overcommit
scenario, when hypervisor set detects that it needs to shuffle some
memory, it instructs the driver to allocate certain number of pages, and
the underlying memory gets returned to the hypervisor. Later hypervisor
may return memory to the guest by reattaching memory to the pageframes and
instructing the driver to "deflate" balloon.
We are submitting a standalone driver because KVM maintainer (Avi Kivity)
expressed opinion (rightly) that our transport does not fit well into
virtqueue paradigm and thus it does not make much sense to integrate with
virtio.
There were also some concerns whether current ballooning technique is the
right thing. If there appears a better framework to achieve this we are
prepared to evaluate and switch to using it, but in the meantime we'd like
to get this driver upstream.
We want to get the driver accepted in distributions so that users do not
have to deal with an out-of-tree module and many distributions have
"upstream first" requirement.
The driver has been shipping for a number of years and users running on
VMware platform will have it installed as part of VMware Tools even if it
will not come from a distribution, thus there should not be additional
risk in pulling the driver into mainline. The driver will only activate
if host is VMware so everyone else should not be affected at all.
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Atom erratum AAE44/AAF40/AAG38/AAH41:
"If software clears the PS (page size) bit in a present PDE (page
directory entry), that will cause linear addresses mapped through this
PDE to use 4-KByte pages instead of using a large page after old TLB
entries are invalidated. Due to this erratum, if a code fetch uses
this PDE before the TLB entry for the large page is invalidated then
it may fetch from a different physical address than specified by
either the old large page translation or the new 4-KByte page
translation. This erratum may also cause speculative code fetches from
incorrect addresses."
[http://download.intel.com/design/processor/specupdt/319536.pdf]
Where as commit 211b3d03c7 seems to
workaround errata AAH41 (mixed 4K TLBs) it reduces the window of
opportunity for the bug to occur and does not totally remove it. This
patch disables mixed 4K/4MB page tables totally avoiding the page
splitting and not tripping this processor issue.
This is based on an original patch by Colin King.
Originally-by: Colin Ian King <colin.king@canonical.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <1269271251-19775-1-git-send-email-colin.king@canonical.com>
Cc: <stable@kernel.org>
When we do a thread switch, we clear the outgoing FS/GS base if the
corresponding selector is nonzero. This is taken by __switch_to() as
an entry invariant; it does not verify that it is true on entry.
However, copy_thread() doesn't enforce this constraint, which can
result in inconsistent results after fork().
Make copy_thread() match the behavior of __switch_to().
Reported-and-tested-by: Samuel Thibault <samuel.thibault@inria.fr>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <4BD1E061.8030605@zytor.com>
Cc: <stable@kernel.org>
This adds support for Memory24, Memory32, and Memory32Fixed descriptors in
PCI host bridge _CRS.
I experimentally determined that Windows (2008 R2) accepts these descriptors
and treats them as windows that are forwarded to the PCI bus, e.g., if
it finds any PCI devices with BARs outside the windows, it moves them into
the windows.
I don't know whether any machines actually use these descriptors in PCI
host bridge _CRS methods, but if any exist and they're new enough that we
automatically turn on "pci=use_crs", they will work with Windows but not
with Linux.
Here are the details: https://bugzilla.kernel.org/show_bug.cgi?id=15817
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'kvm-updates/2.6.34' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Fix TSS size check for 16-bit tasks
KVM: Add missing srcu_read_lock() for kvm_mmu_notifier_release()
KVM: Increase NR_IOBUS_DEVS limit to 200
KVM: fix the handling of dirty bitmaps to avoid overflows
KVM: MMU: fix kvm_mmu_zap_page() and its calling path
KVM: VMX: Save/restore rflags.vm correctly in real mode
KVM: allow bit 10 to be cleared in MSR_IA32_MC4_CTL
KVM: Don't spam kernel log when injecting exceptions due to bad cr writes
KVM: SVM: Fix memory leaks that happen when svm_create_vcpu() fails
KVM: take srcu lock before call to complete_pio()
A 16-bit TSS is only 44 bytes long. So make sure to test for the correct
size on task switch.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
APB timer is used on Moorestown platforms but not on a standard PC.
If APB timer code is compiled in but not initialized at run-time due
to lack of FW reported SFI table, kernel would panic when the non-boot
CPUs are offlined and notifier is called.
https://bugzilla.kernel.org/show_bug.cgi?id=15786
This patch ensures CPU hotplug notifier for APB timer is only registered
when the APBT timer block is initialized.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
LKML-Reference: <1271701423-1162-1-git-send-email-jacob.jun.pan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Before commit e28cbf2293 ("improve
sys_newuname() for compat architectures") 64-bit x86 had a private
implementation of sys_uname which was just called sys_uname, which other
architectures used for the old uname.
Due to some merge issues with the uname refactoring patches we ended up
calling the old uname version for both the old and new system call
slots, which lead to the domainname filed never be set which caused
failures with libnss_nis.
Reported-and-tested-by: Andy Isaacson <adi@hexapodia.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Int is not long enough to store the size of a dirty bitmap.
This patch fixes this problem with the introduction of a wrapper
function to calculate the sizes of dirty bitmaps.
Note: in mark_page_dirty(), we have to consider the fact that
__set_bit() takes the offset as int, not long.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Currently we set eflags.vm unconditionally when entering real mode emulation
through virtual-8086 mode, and clear it unconditionally when we enter protected
mode. The means that the following sequence
KVM_SET_REGS (rflags.vm=1)
KVM_SET_SREGS (cr0.pe=1)
Ends up with rflags.vm clear due to KVM_SET_SREGS triggering enter_pmode().
Fix by shadowing rflags.vm (and rflags.iopl) correctly while in real mode:
reads and writes to those bits access a shadow register instead of the actual
register.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
There is a quirk for AMD K8 CPUs in many Linux kernels (see
arch/x86/kernel/cpu/mcheck/mce.c:__mcheck_cpu_apply_quirks()) that
clears bit 10 in that MCE related MSR. KVM can only cope with all
zeros or all ones, so it will inject a #GP into the guest, which
will let it panic.
So lets add a quirk to the quirk and ignore this single cleared bit.
This fixes -cpu kvm64 on all machines and -cpu host on K8 machines
with some guest Linux kernels.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
svm_create_vcpu() does not free the pages allocated during the creation
when it fails to complete the allocations. This patch fixes it.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
complete_pio() may use slot table which is protected by srcu.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
This is a partial revert of 4cd8b5e2a1 "lguest: use KVM hypercalls";
we revert to using (just as questionable but more reliable) int $15 for
hypercalls. I didn't revert the register mapping, so we still use the
same calling convention as kvm.
KVM in more recent incarnations stopped injecting a fault when a guest
tried to use the VMCALL instruction from ring 1, so lguest under kvm
fails to make hypercalls. It was nice to share code with our KVM
cousins, but this was overreach.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Matias Zabaljauregui <zabaljauregui@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
When we fetch the hot regs and rewind to the nth caller, it
might happen that we dereference a frame pointer outside the
kernel stack boundaries, like in this example:
perf_trace_sched_switch+0xd5/0x120
schedule+0x6b5/0x860
retint_careful+0xd/0x21
Since we directly dereference a userspace frame pointer here while
rewinding behind retint_careful, this may end up in a crash.
Fix this by simply using probe_kernel_address() when we rewind the
frame pointer.
This issue will have a much more proper fix in the next version of the
perf_arch_fetch_caller_regs() API that will only need to rewind to the
first caller.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: David Miller <davem@davemloft.net>
Cc: Archs <linux-arch@vger.kernel.org>
ACPI Address Space Descriptors (used in _CRS) have a Consumer/Producer
bit that is supposed to distinguish regions that are consumed directly
by a device from those that are forwarded ("produced") by a bridge.
But BIOSes have apparently not used this consistently, and Windows
seems to ignore it, so I think Linux should ignore it as well.
I can't point to any of these supposed broken BIOSes, but since we
now rely on _CRS by default, I think it's safer to ignore this bit
from the start.
Here are details of my experiments with how Windows handles it:
https://bugzilla.kernel.org/show_bug.cgi?id=15701
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip:
x86: Fix double enable_IR_x2apic() call on SMP kernel on !SMP boards
x86: Increase CONFIG_NODES_SHIFT max to 10
ibft, x86: Change reserve_ibft_region() to find_ibft_region()
x86, hpet: Fix bug in RTC emulation
x86, hpet: Erratum workaround for read after write of HPET comparator
bootmem, x86: Fix 32bit numa system without RAM on node 0
nobootmem, x86: Fix 32bit numa system without RAM on node 0
x86: Handle overlapping mptables
x86: Make e820_remove_range to handle all covered case
x86-32, resume: do a global tlb flush in S4 resume
If we boot into a crash-kernel the gart might still be
enabled and its caches might be dirty. This can result in
undefined behavior later. Fix it by explicitly disabling the
gart hardware before initialization and flushing the caches
after enablement.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>