Pull timer and x86 fix from Ingo Molnar:
"A CLOCK_TAI early expiry fix and an x86 microcode driver oops fix"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Fix incorrect tai offset calculation for non high-res timer systems
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, microcode: Return error from driver init code when loader is disabled
In acpi_table_parse(), pointer of the table to pass to handler() is
checked before handler() called, so remove all the duplicate NULL
check in the handler function.
CC: Tony Luck <tony.luck@intel.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
While perfmon2 is a sufficiently evil library (it pokes MSRs
directly) that breaking it is fair game, it's still useful, so we
might as well try to support it. This allows users to write 2 to
/sys/devices/cpu/rdpmc to disable all rdpmc protection so that hack
like perfmon2 can continue to work.
At some point, if perf_event becomes fast enough to replace
perfmon2, then this can go.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/caac3c1c707dcca48ecbc35f4def21495856f479.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We currently allow any process to use rdpmc. This significantly
weakens the protection offered by PR_TSC_DISABLED, and it could be
helpful to users attempting to exploit timing attacks.
Since we can't enable access to individual counters, use a very
coarse heuristic to limit access to rdpmc: allow access only when
a perf_event is mmapped. This protects seccomp sandboxes.
There is plenty of room to further tighen these restrictions. For
example, this allows rdpmc for any x86_pmu event, but it's only
useful for self-monitoring tasks.
As a side effect, cap_user_rdpmc will now be false for AMD uncore
events. This isn't a real regression, since .event_idx is disabled
for these events anyway for the time being. Whenever that gets
re-added, the cap_user_rdpmc code can be adjusted or refactored
accordingly.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/a2bdb3cf3a1d70c26980d7c6dddfbaa69f3182bf.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Context switches and TLB flushes can change individual bits of CR4.
CR4 reads take several cycles, so store a shadow copy of CR4 in a
per-cpu variable.
To avoid wasting a cache line, I added the CR4 shadow to
cpu_tlbstate, which is already touched in switch_mm. The heaviest
users of the cr4 shadow will be switch_mm and __switch_to_xtra, and
__switch_to_xtra is called shortly after switch_mm during context
switch, so the cacheline is likely to be hot.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CR4 manipulation was split, seemingly at random, between direct
(write_cr4) and using a helper (set/clear_in_cr4). Unfortunately,
the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code,
which only a small subset of users actually wanted.
This patch replaces all cr4 access in functions that don't leave cr4
exactly the way they found it with new helpers cr4_set_bits,
cr4_clear_bits, and cr4_set_bits_and_update_boot.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rename CONFIG_LIVE_PATCHING to CONFIG_LIVEPATCH to make the naming of
the config and the code more consistent.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This fixes a bug in the RCU code I added in ist_enter. It also includes
the sysret stuff discussed here:
http://lkml.kernel.org/g/cover.1421453410.git.luto%40amacapital.net
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Merge tag 'pr-20150201-x86-entry' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/asm
Pull "x86: Entry cleanups and a bugfix for 3.20" from Andy Lutomirski:
" This fixes a bug in the RCU code I added in ist_enter. It also includes
the sysret stuff discussed here:
http://lkml.kernel.org/g/cover.1421453410.git.luto%40amacapital.net "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'v3.19-rc7' into x86/asm, to refresh the branch before pulling in new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support for specifying PCI based UARTs for earlyprintk
using a syntax like "earlyprintk=pciserial,00:18.1,115200",
where 00:18.1 is the BDF of a UART device.
[Slightly tidied from Stuart's original patch]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Intel Moorestown platform support was removed few years ago. This is a follow
up which removes Moorestown specific code for the serial devices. It includes
mrst_max3110 and earlyprintk bits.
This was used on SFI (Medfield, Clovertrail) based platforms as well, though
new ones use normal serial interface for the console service.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We used to optimize rescheduling and audit on syscall exit. Now
that the full slow path is reasonably fast, remove these
optimizations. Syscall exit auditing is now handled exclusively by
syscall_trace_leave.
This adds something like 10ns to the previously optimized paths on
my computer, presumably due mostly to SAVE_REST / RESTORE_REST.
I think that we should eventually replace both the syscall and
non-paranoid interrupt exit slow paths with a pair of C functions
along the lines of the syscall entry hooks.
Link: http://lkml.kernel.org/r/22f2aa4a0361707a5cfb1de9d45260b39965dead.1421453410.git.luto@amacapital.net
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
The x86_64 entry code currently jumps through complex and
inconsistent hoops to try to minimize the impact of syscall exit
work. For a true fast-path syscall, almost nothing needs to be
done, so returning is just a check for exit work and sysret. For a
full slow-path return from a syscall, the C exit hook is invoked if
needed and we join the iret path.
Using iret to return to userspace is very slow, so the entry code
has accumulated various special cases to try to do certain forms of
exit work without invoking iret. This is error-prone, since it
duplicates assembly code paths, and it's dangerous, since sysret
can malfunction in interesting ways if used carelessly. It's
also inefficient, since a lot of useful cases aren't optimized
and therefore force an iret out of a combination of paranoia and
the fact that no one has bothered to write even more asm code
to avoid it.
I would argue that this approach is backwards. Rather than trying
to avoid the iret path, we should instead try to make the iret path
fast. Under a specific set of conditions, iret is unnecessary. In
particular, if RIP==RCX, RFLAGS==R11, RIP is canonical, RF is not
set, and both SS and CS are as expected, then
movq 32(%rsp),%rsp;sysret does the same thing as iret. This set of
conditions is nearly always satisfied on return from syscalls, and
it can even occasionally be satisfied on return from an irq.
Even with the careful checks for sysret applicability, this cuts
nearly 80ns off of the overhead from syscalls with unoptimized exit
work. This includes tracing and context tracking, and any return
that invokes KVM's user return notifier. For example, the cost of
getpid with CONFIG_CONTEXT_TRACKING_FORCE=y drops from ~360ns to
~280ns on my computer.
This may allow the removal and even eventual conversion to C
of a respectable amount of exit asm.
This may require further tweaking to give the full benefit on Xen.
It may be worthwhile to adjust signal delivery and exec to try hit
the sysret path.
This does not optimize returns to 32-bit userspace. Making the same
optimization for CS == __USER32_CS is conceptually straightforward,
but it will require some tedious code to handle the differences
between sysretl and sysexitl.
Link: http://lkml.kernel.org/r/71428f63e681e1b4aa1a781e3ef7c27f027d1103.1421453410.git.luto@amacapital.net
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
context_tracking_user_exit() has no effect if in_interrupt() returns true,
so ist_enter() didn't work. Fix it by calling exception_enter(), and thus
context_tracking_user_exit(), before incrementing the preempt count.
This also adds an assertion that will catch the problem reliably if
CONFIG_PROVE_RCU=y to help prevent the bug from being reintroduced.
Link: http://lkml.kernel.org/r/261ebee6aee55a4724746d0d7024697013c40a08.1422709102.git.luto@amacapital.net
Fixes: 9592747538 x86, traps: Track entry into and exit from IST context
Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
The new hw_breakpoint bits are now ready for v3.20, merge them
into the main branch, to avoid conflicts.
Conflicts:
tools/perf/Documentation/perf-record.txt
Signed-off-by: Ingo Molnar <mingo@kernel.org>
of this is an IST rework. When an IST exception interrupts user
space, we will handle it on the per-thread kernel stack instead of
on the IST stack. This sounds messy, but it actually simplifies the
IST entry/exit code, because it eliminates some ugly games we used
to play in order to handle rescheduling, signal delivery, etc on the
way out of an IST exception.
The IST rework introduces proper context tracking to IST exception
handlers. I haven't seen any bug reports, but the old code could
have incorrectly treated an IST exception handler as an RCU extended
quiescent state.
The memory failure change (included in this pull request with
Borislav and Tony's permission) eliminates a bunch of code that
is no longer needed now that user memory failure handlers are
called in process context.
Finally, this includes a few on Denys' uncontroversial and Obviously
Correct (tm) cleanups.
The IST and memory failure changes have been in -next for a while.
LKML references:
IST rework:
http://lkml.kernel.org/r/cover.1416604491.git.luto@amacapital.net
Memory failure change:
http://lkml.kernel.org/r/54ab2ffa301102cd6e@agluck-desk.sc.intel.com
Denys' cleanups:
http://lkml.kernel.org/r/1420927210-19738-1-git-send-email-dvlasenk@redhat.com
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Merge tag 'pr-20150114-x86-entry' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux into x86/asm
Pull x86/entry enhancements from Andy Lutomirski:
" This is my accumulated x86 entry work, part 1, for 3.20. The meat
of this is an IST rework. When an IST exception interrupts user
space, we will handle it on the per-thread kernel stack instead of
on the IST stack. This sounds messy, but it actually simplifies the
IST entry/exit code, because it eliminates some ugly games we used
to play in order to handle rescheduling, signal delivery, etc on the
way out of an IST exception.
The IST rework introduces proper context tracking to IST exception
handlers. I haven't seen any bug reports, but the old code could
have incorrectly treated an IST exception handler as an RCU extended
quiescent state.
The memory failure change (included in this pull request with
Borislav and Tony's permission) eliminates a bunch of code that
is no longer needed now that user memory failure handlers are
called in process context.
Finally, this includes a few on Denys' uncontroversial and Obviously
Correct (tm) cleanups.
The IST and memory failure changes have been in -next for a while.
LKML references:
IST rework:
http://lkml.kernel.org/r/cover.1416604491.git.luto@amacapital.net
Memory failure change:
http://lkml.kernel.org/r/54ab2ffa301102cd6e@agluck-desk.sc.intel.com
Denys' cleanups:
http://lkml.kernel.org/r/1420927210-19738-1-git-send-email-dvlasenk@redhat.com
"
This tree semantically depends on and is based on the following RCU commit:
734d168013 ("rcu: Make rcu_nmi_enter() handle nesting")
... and for that reason won't be pushed upstream before the RCU bits hit Linus's tree.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a systematic crash in rapl_scale()
due to an invalid pointer.
The bug was introduced by commit:
89cbc76768 ("x86: Replace __get_cpu_var uses")
The fix is simple. Just put the parenthesis where it needs
to be, i.e., around rapl_pmu. To my surprise, the compiler
was not complaining about passing an integer instead of a
pointer.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 89cbc76768 ("x86: Replace __get_cpu_var uses")
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: cl@linux.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150122203834.GA10228@thinkpad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There were some issues about the uncore driver tried to access
non-existing boxes, which caused boot crashes. These issues have
been all fixed. But we should avoid boot failures if that ever
happens again.
This patch intends to prevent this kind of potential issues.
It moves uncore_box_init out of driver initialization. The box
will be initialized when it's first enabled.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421729665-5912-1-git-send-email-kan.liang@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commits 65cef1311d ("x86, microcode: Add a disable chicken bit") and
a18a0f6850 ("x86, microcode: Don't initialize microcode code on
paravirt") allow microcode driver skip initialization when microcode
loading is not permitted.
However, they don't prevent the driver from being loaded since the
init code returns 0. If at some point later the driver gets unloaded
this will result in an oops while trying to deregister the (never
registered) device.
To avoid this, make init code return an error on paravirt or when
microcode loading is disabled. The driver will then never be loaded.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1422411669-25147-1-git-send-email-boris.ostrovsky@oracle.com
Reported-by: James Digwall <james@dingwall.me.uk>
Cc: stable@vger.kernel.org # 3.18
Signed-off-by: Borislav Petkov <bp@suse.de>
Pull x86 fixes from Thomas Gleixner:
"Hopefully the last round of fixes for 3.19
- regression fix for the LDT changes
- regression fix for XEN interrupt handling caused by the APIC
changes
- regression fixes for the PAT changes
- last minute fixes for new the MPX support
- regression fix for 32bit UP
- fix for a long standing relocation issue on 64bit tagged for stable
- functional fix for the Hyper-V clocksource tagged for stable
- downgrade of a pr_err which tends to confuse users
Looks a bit on the large side, but almost half of it are valuable
comments"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tsc: Change Fast TSC calibration failed from error to info
x86/apic: Re-enable PCI_MSI support for non-SMP X86_32
x86, mm: Change cachemode exports to non-gpl
x86, tls: Interpret an all-zero struct user_desc as "no segment"
x86, tls, ldt: Stop checking lm in LDT_empty
x86, mpx: Strictly enforce empty prctl() args
x86, mpx: Fix potential performance issue on unmaps
x86, mpx: Explicitly disable 32-bit MPX support on 64-bit kernels
x86, hyperv: Mark the Hyper-V clocksource as being continuous
x86: Don't rely on VMWare emulating PAT MSR correctly
x86, irq: Properly tag virtualization entry in /proc/interrupts
x86, boot: Skip relocs when load address unchanged
x86/xen: Override ACPI IRQ management callback __acpi_unregister_gsi
ACPI: pci: Do not clear pci_dev->irq in acpi_pci_irq_disable()
x86/xen: Treat SCI interrupt as normal GSI interrupt
The argument 3 of sanitize_e820_map() will only be updated upon a
successful sanitization. Some of the callers have extra conditionals
for the same purpose. Clean them up.
default_machine_specific_memory_setup() must keep the extra
conditional because boot_params.e820_entries is an u8 and not an u32,
so the direct update would overwrite other fields in boot_params.
[ tglx: Massaged changelog ]
Signed-off-by: WANG Chao <chaowang@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Lee Chun-Yi <joeyli.kernel@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Link: http://lkml.kernel.org/r/1420601859-18439-1-git-send-email-chaowang@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
early_memremap() takes care of page alignment and map size, so we can
just remap the required data size and get rid of the adjustments in
the setup code.
[tglx: Massaged changelog ]
Signed-off-by: WANG Chao <chaowang@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Link: http://lkml.kernel.org/r/1420628150-16872-1-git-send-email-chaowang@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Many users see this message when booting without knowning that it is
of no importance and that TSC calibration may have succeeded by
another way.
As explained by Paul Bolle in
http://lkml.kernel.org/r/1348488259.1436.22.camel@x61.thuisdomein
"Fast TSC calibration failed" should not be considered as an error
since other calibration methods are being tried afterward. At most,
those send a warning if they fail (not an error). So let's change
the message from error to warning.
[ tglx: Make if pr_info. It's really not important at all ]
Fixes: c767a54ba0 x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>
Signed-off-by: Alexandre Demers <alexandre.f.demers@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1418106470-6906-1-git-send-email-alexandre.f.demers@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Building with clang:
CC arch/x86/kernel/rtc.o
arch/x86/kernel/rtc.c:173:29: warning: duplicate 'const' declaration
specifier [-Wduplicate-decl-specifier]
static const char * const const ids[] __initconst =
Remove the duplicate const, it is not needed and causes a warning.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: http://lkml.kernel.org/r/1421244475-313-1-git-send-email-colin.king@canonical.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The Witcher 2 did something like this to allocate a TLS segment index:
struct user_desc u_info;
bzero(&u_info, sizeof(u_info));
u_info.entry_number = (uint32_t)-1;
syscall(SYS_set_thread_area, &u_info);
Strictly speaking, this code was never correct. It should have set
read_exec_only and seg_not_present to 1 to indicate that it wanted
to find a free slot without putting anything there, or it should
have put something sensible in the TLS slot if it wanted to allocate
a TLS entry for real. The actual effect of this code was to
allocate a bogus segment that could be used to exploit espfix.
The set_thread_area hardening patches changed the behavior, causing
set_thread_area to return -EINVAL and crashing the game.
This changes set_thread_area to interpret this as a request to find
a free slot and to leave it empty, which isn't *quite* what the game
expects but should be close enough to keep it working. In
particular, using the code above to allocate two segments will
allocate the same segment both times.
According to FrostbittenKing on Github, this fixes The Witcher 2.
If this somehow still causes problems, we could instead allocate
a limit==0 32-bit data segment, but that seems rather ugly to me.
Fixes: 41bdc78544 x86/tls: Validate TLS entries to protect espfix
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: stable@vger.kernel.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/0cb251abe1ff0958b8e468a9a9a905b80ae3a746.1421954363.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
First two are minor fallout from the param rework which went in this merge
window.
Next three are a series which fixes a longstanding (but never previously
reported and unlikely , so no CC stable) race between kallsyms and freeing
the init section.
Finally, a minor cleanup as our module refcount will now be -1 during
unload.
Thanks,
Rusty.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module and param fixes from Rusty Russell:
"Surprising number of fixes this merge window :(
The first two are minor fallout from the param rework which went in
this merge window.
The next three are a series which fixes a longstanding (but never
previously reported and unlikely , so no CC stable) race between
kallsyms and freeing the init section.
Finally, a minor cleanup as our module refcount will now be -1 during
unload"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
module: make module_refcount() a signed integer.
module: fix race in kallsyms resolution during module load success.
module: remove mod arg from module_free, rename module_memfree().
module_arch_freeing_init(): new hook for archs before module->module_init freed.
param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOC
param: initialize store function to NULL if not available.
Now that the APIC bringup is consolidated we can move the setup call
for the percpu clock event device to apic_bsp_setup().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211704.162567839@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Extend apic_bsp_setup() so the same code flow can be used for
APIC_init_uniprocessor().
Folded Jiangs fix to provide proper ordering of the UP setup.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211704.084765674@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The UP related setups for local apic are mangled into smp_sanity_check().
That results in duplicate calls to disable_smp() and makes the code
hard to follow. Let smp_sanity_check() return dedicated values for the
various exit reasons and handle them at the call site.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.987833932@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We better provide proper functions which implement the required code
flow in the apic code rather than letting the smpboot code open code
it. That allows to make more functions static and confines the APIC
functionality to apic.c where it belongs.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.907616730@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The UP local API support can be set up from an early initcall. No need
for horrible hackery in the init code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211703.827943883@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Move the code to a different place so we can make other functions
inline. Preparatory patch for further cleanups. No change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.731329006@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
smpboot is very creative with the ways to disable ioapic.
smpboot_clear_io_apic() smpboot_clear_io_apic_irqs() and
disable_ioapic_support() serve a similar purpose.
smpboot_clear_io_apic_irqs() is the most useless of all
functions as it clears a variable which has not been setup yet.
Aside of that it has the same ifdef mess and conditionals around the
ioapic related code, which can now be removed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.650280684@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We have proper stubs for the IOAPIC=n case and the setup/enable
function have the required checks inside now. Remove the ifdeffery and
the copy&pasted conditionals.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>C
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.569830549@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No point to have the same checks at every call site. Add them to the
functions, so they can be called unconditionally.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.490719938@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No point for a separate header file.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211703.304126687@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Use the state information to simplify the disable logic further.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.209387598@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
enable_x2apic() is a convoluted unreadable mess because it is used for
both enablement in early boot and for setup in cpu_init().
Split the code into x2apic_enable() for enablement and x2apic_setup()
for setup of (secondary cpus). Make use of the new state tracking to
simplify the logic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211703.129287153@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There is no point in postponing the hardware disablement of x2apic. It
can be disabled right away in the nox2apic setup function.
Disable it right away and set the state to DISABLED . This allows to
remove all the nox2apic conditionals all over the place.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211703.051214090@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Having 3 different variables to track the state is just silly and
error prone. Add a proper state tracking variable which covers the
three possible states: ON/OFF/DISABLED.
We cannot use x2apic_mode for this as this would require to change all
users of x2apic_mode with explicit comparisons for a state value
instead of treating it as boolean.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211702.955392443@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Rename the argument of try_to_enable_x2apic() so the purpose becomes
more clear.
Make the pr_warning more consistent and avoid the double print of
"disabling".
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211702.876012628@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No point in having try_to_enable_x2apic() outside of the
CONFIG_X86_X2APIC section and having inline functions and more ifdefs
to deal with it. Move the code into the existing ifdef section and
remove the inline cruft.
Fixup the printk about not enabling interrupt remapping as suggested
by Boris.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211702.795388613@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No point in delaying the x2apic detection for the CONFIG_X86_X2APIC=n
case to enable_IR_x2apic(). We rather detect that before we try to
setup anything there.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211702.702479404@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If x2apic_preenabled is not enabled, then disable_x2apic() is not
called from various places which results in x2apic_disabled not being
set. So other code pathes can happily reenable the x2apic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211702.621431109@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The x2apic_preenabled flag is just a horrible hack and if X2APIC
support is disabled it does not reflect the actual hardware
state. Check the hardware instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211702.541280622@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Having several disjunct pieces of code for x2apic support makes
reading the code unnecessarily hard. Move it to one ifdeffed section.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211702.445212133@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No point in having a static variable around which is always 0. Let the
compiler optimize code out if disabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211702.363274310@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
enable_IR_x2apic() grew a open coded x2apic detection. Implement a
proper helper function which shares the code with the already existing
x2apic_enabled().
Made it use rdmsrl_safe as suggested by Boris.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211702.285038186@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
math_state_restore() can race with kernel_fpu_begin() if irq comes
right after __thread_fpu_begin(), __save_init_fpu() will overwrite
fpu->state we are going to restore.
Add 2 simple helpers, kernel_fpu_disable() and kernel_fpu_enable()
which simply set/clear in_kernel_fpu, and change math_state_restore()
to exclude kernel_fpu_begin() in between.
Alternatively we could use local_irq_save/restore, but probably these
new helpers can have more users.
Perhaps they should disable/enable preemption themselves, in this case
we can remove preempt_disable() in __restore_xstate_sig().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: matt.fleming@intel.com
Cc: bp@suse.de
Cc: pbonzini@redhat.com
Cc: luto@amacapital.net
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/20150115192028.GD27332@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Now that we have in_kernel_fpu we can remove __thread_clear_has_fpu()
in __kernel_fpu_begin(). And this allows to replace the asymmetrical
and nontrivial use_eager_fpu + tsk_used_math check in kernel_fpu_end()
with the same __thread_has_fpu() check.
The logic becomes really simple; if _begin() does save() then _end()
needs restore(), this is controlled by __thread_has_fpu(). Otherwise
they do clts/stts unless use_eager_fpu().
Not only this makes begin/end symmetrical and imo more understandable,
potentially this allows to change irq_fpu_usable() to avoid all other
checks except "in_kernel_fpu".
Also, with this patch __kernel_fpu_end() does restore_fpu_checking()
and WARNs if it fails instead of math_state_restore(). I think this
looks better because we no longer need __thread_fpu_begin(), and it
would be better to report the failure in this case.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: matt.fleming@intel.com
Cc: bp@suse.de
Cc: pbonzini@redhat.com
Cc: luto@amacapital.net
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/20150115192005.GC27332@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
interrupted_kernel_fpu_idle() tries to detect if kernel_fpu_begin()
is safe or not. In particular it should obviously deny the nested
kernel_fpu_begin() and this logic looks very confusing.
If use_eager_fpu() == T we rely on a) __thread_has_fpu() check in
interrupted_kernel_fpu_idle(), and b) on the fact that _begin() does
__thread_clear_has_fpu().
Otherwise we demand that the interrupted task has no FPU if it is in
kernel mode, this works because __kernel_fpu_begin() does clts() and
interrupted_kernel_fpu_idle() checks X86_CR0_TS.
Add the per-cpu "bool in_kernel_fpu" variable, and change this code
to check/set/clear it. This allows to do more cleanups and fixes, see
the next changes.
The patch also moves WARN_ON_ONCE() under preempt_disable() just to
make this_cpu_read() look better, this is not really needed. And in
fact I think we should move it into __kernel_fpu_begin().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: matt.fleming@intel.com
Cc: bp@suse.de
Cc: pbonzini@redhat.com
Cc: luto@amacapital.net
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/20150115191943.GB27332@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The PSS register reflects the power state of each island on SoC. It would be
useful to know which of the islands is on or off at the momemnt.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P. Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1421253575-22509-6-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There is no need to use err variable.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P. Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1421253575-22509-5-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
DRIVER_NAME seems unused. This patch just removes it. There is no functional
change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P. Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1421253575-22509-4-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
debugfs_remove_recursive() is NULL-aware, thus, we may safely remove the check
here. There is no need to assing NULL to variable since it will be not used
anywhere.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P. Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1421253575-22509-3-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
pmc_dbgfs_unregister() will be called when pmc->dbgfs_dir is unconditionally
NULL on error path in pmc_dbgfs_register(). To prevent this we move the
assignment to where is should be.
Fixes: f855911c1f (x86/pmc_atom: Expose PMC device state and platform sleep state)
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P. Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1421253575-22509-2-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Currently Xen Domain0 has special treatment for ACPI SCI interrupt,
that is initialize irq for ACPI SCI at early stage in a special way as:
xen_init_IRQ()
->pci_xen_initial_domain()
->xen_setup_acpi_sci()
Allocate and initialize irq for ACPI SCI
Function xen_setup_acpi_sci() calls acpi_gsi_to_irq() to get an irq
number for ACPI SCI. But unfortunately acpi_gsi_to_irq() depends on
IOAPIC irqdomains through following path
acpi_gsi_to_irq()
->mp_map_gsi_to_irq()
->mp_map_pin_to_irq()
->check IOAPIC irqdomain
For PV domains, it uses Xen event based interrupt manangement and
doesn't make uses of native IOAPIC, so no irqdomains created for IOAPIC.
This causes Xen domain0 fail to install interrupt handler for ACPI SCI
and all ACPI events will be lost. Please refer to:
https://lkml.org/lkml/2014/12/19/178
So the fix is to get rid of special treatment for ACPI SCI, just treat
ACPI SCI as normal GSI interrupt as:
acpi_gsi_to_irq()
->acpi_register_gsi()
->acpi_register_gsi_xen()
->xen_register_gsi()
With above change, there's no need for xen_setup_acpi_sci() anymore.
The above change also works with bare metal kernel too.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Tony Luck <tony.luck@intel.com>
Cc: xen-devel@lists.xenproject.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1421720467-7709-2-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Nothing needs the module pointer any more, and the next patch will
call it from RCU, where the module itself might no longer exist.
Removing the arg is the safest approach.
This just codifies the use of the module_alloc/module_free pattern
which ftrace and bpf use.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: x86@kernel.org
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: linux-cris-kernel@axis.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: nios2-dev@lists.rocketboards.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: netdev@vger.kernel.org
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, but also two PMU driver fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf tools powerpc: Use dwfl_report_elf() instead of offline.
perf tools: Fix segfault for symbol annotation on TUI
perf test: Fix dwarf unwind using libunwind.
perf tools: Avoid build splat for syscall numbers with uclibc
perf tools: Elide strlcpy warning with uclibc
perf tools: Fix statfs.f_type data type mismatch build error with uclibc
tools: Remove bitops/hweight usage of bits in tools/perf
perf machine: Fix __machine__findnew_thread() error path
perf tools: Fix building error in x86_64 when dwarf unwind is on
perf probe: Propagate error code when write(2) failed
perf/x86/intel: Fix bug for "cycles:p" and "cycles:pp" on SLM
perf/rapl: Fix sysfs_show() initialization for RAPL PMU
The int_ret_from_sys_call and syscall tracing code disagrees
with the sysret path as to the value of RCX.
The Intel SDM, the AMD APM, and my laptop all agree that sysret
returns with RCX == RIP. The syscall tracing code does not
respect this property.
For example, this program:
int main()
{
extern const char syscall_rip[];
unsigned long rcx = 1;
unsigned long orig_rcx = rcx;
asm ("mov $-1, %%eax\n\t"
"syscall\n\t"
"syscall_rip:"
: "+c" (rcx) : : "r11");
printf("syscall: RCX = %lX RIP = %lX orig RCX = %lx\n",
rcx, (unsigned long)syscall_rip, orig_rcx);
return 0;
}
prints:
syscall: RCX = 400556 RIP = 400556 orig RCX = 1
Running it under strace gives this instead:
syscall: RCX = FFFFFFFFFFFFFFFF RIP = 400556 orig RCX = 1
This changes FIXUP_TOP_OF_STACK to match sysret, causing the
test to show RCX == RIP even under strace.
It looks like this is a partial revert of:
88e4bc32686e ("[PATCH] x86-64 architecture specific sync for 2.5.8")
from the historic git tree.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/c9a418c3dc3993cb88bb7773800225fd318a4c67.1421453410.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
the mixture of function graph tracing and kprobes.
When jprobes and function graph tracing is enabled at the same time
it will crash the system.
# modprobe jprobe_example
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
After the first fork (jprobe_example probes it), the system will crash.
This is due to the way jprobes copies the stack frame and does not
do a normal function return. This messes up with the function graph
tracing accounting which hijacks the return address from the stack
and replaces it with a hook function. It saves the return addresses in
a separate stack to put back the correct return address when done.
But because the jprobe functions do not do a normal return, their
stack addresses are not put back until the function they probe is called,
which means that the probed function will get the return address of
the jprobe handler instead of its own.
The simple fix here was to disable function graph tracing while the
jprobe handler is being called.
While debugging this I found two minor bugs with the function graph
tracing.
The first was about the function graph tracer sharing its function hash
with the function tracer (they both get filtered by the same input).
The changing of the set_ftrace_filter would not sync the function recording
records after a change if the function tracer was disabled but the
function graph tracer was enabled. This was due to the update only checking
one of the ops instead of the shared ops to see if they were enabled and
should perform the sync. This caused the ftrace accounting to break and
a ftrace_bug() would be triggered, disabling ftrace until a reboot.
The second was that the check to update records only checked one of the
filter hashes. It needs to test both the "filter" and "notrace" hashes.
The "filter" hash determines what functions to trace where as the "notrace"
hash determines what functions not to trace (trace all but these).
Both hashes need to be passed to the update code to find out what change
is being done during the update. This also broke the ftrace record
accounting and triggered a ftrace_bug().
This patch set also include two more fixes that were reported separately
from the kprobe issue.
One was that init_ftrace_syscalls() was called twice at boot up.
This is not a major bug, but that call performed a rather large kmalloc
(NR_syscalls * sizeof(*syscalls_metadata)). The second call made the first
one a memory leak, and wastes memory.
The other fix is a regression caused by an update in the v3.19 merge window.
The moving to enable events early, moved the enabling before PID 1 was
created. The syscall events require setting the TIF_SYSCALL_TRACEPOINT
for all tasks. But for_each_process_thread() does not include the swapper
task (PID 0), and ended up being a nop. A suggested fix was to add
the init_task() to have its flag set, but I didn't really want to mess
with PID 0 for this minor bug. Instead I disable and re-enable events again
at early_initcall() where it use to be enabled. This also handles any other
event that might have its own reg function that could break at early
boot up.
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Merge tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fixes from Steven Rostedt:
"This holds a few fixes to the ftrace infrastructure as well as the
mixture of function graph tracing and kprobes.
When jprobes and function graph tracing is enabled at the same time it
will crash the system:
# modprobe jprobe_example
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
After the first fork (jprobe_example probes it), the system will
crash.
This is due to the way jprobes copies the stack frame and does not do
a normal function return. This messes up with the function graph
tracing accounting which hijacks the return address from the stack and
replaces it with a hook function. It saves the return addresses in a
separate stack to put back the correct return address when done. But
because the jprobe functions do not do a normal return, their stack
addresses are not put back until the function they probe is called,
which means that the probed function will get the return address of
the jprobe handler instead of its own.
The simple fix here was to disable function graph tracing while the
jprobe handler is being called.
While debugging this I found two minor bugs with the function graph
tracing.
The first was about the function graph tracer sharing its function
hash with the function tracer (they both get filtered by the same
input). The changing of the set_ftrace_filter would not sync the
function recording records after a change if the function tracer was
disabled but the function graph tracer was enabled. This was due to
the update only checking one of the ops instead of the shared ops to
see if they were enabled and should perform the sync. This caused the
ftrace accounting to break and a ftrace_bug() would be triggered,
disabling ftrace until a reboot.
The second was that the check to update records only checked one of
the filter hashes. It needs to test both the "filter" and "notrace"
hashes. The "filter" hash determines what functions to trace where as
the "notrace" hash determines what functions not to trace (trace all
but these). Both hashes need to be passed to the update code to find
out what change is being done during the update. This also broke the
ftrace record accounting and triggered a ftrace_bug().
This patch set also include two more fixes that were reported
separately from the kprobe issue.
One was that init_ftrace_syscalls() was called twice at boot up. This
is not a major bug, but that call performed a rather large kmalloc
(NR_syscalls * sizeof(*syscalls_metadata)). The second call made the
first one a memory leak, and wastes memory.
The other fix is a regression caused by an update in the v3.19 merge
window. The moving to enable events early, moved the enabling before
PID 1 was created. The syscall events require setting the
TIF_SYSCALL_TRACEPOINT for all tasks. But for_each_process_thread()
does not include the swapper task (PID 0), and ended up being a nop.
A suggested fix was to add the init_task() to have its flag set, but I
didn't really want to mess with PID 0 for this minor bug. Instead I
disable and re-enable events again at early_initcall() where it use to
be enabled. This also handles any other event that might have its own
reg function that could break at early boot up"
* tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix enabling of syscall events on the command line
tracing: Remove extra call to init_ftrace_syscalls()
ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing
ftrace: Check both notrace and filter for old hash
ftrace: Fix updating of filters for shared global_ops filters
cycles:p and cycles:pp do not work on SLM since commit:
86a04461a9 ("perf/x86: Revamp PEBS event selection")
UOPS_RETIRED.ALL is not a PEBS capable event, so it should not be used
to count cycle number.
Actually SLM calls intel_pebs_aliases_core2() which uses INST_RETIRED.ANY_P
to count the number of cycles. It's a PEBS capable event. But inv and
cmask must be set to count cycles.
Considering SLM allows all events as PEBS with no flags, only
INST_RETIRED.ANY_P, inv=1, cmask=16 needs to handled specially.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421084541-31639-1-git-send-email-kan.liang@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a problem with the initialization of the
sysfs_show() routine for the RAPL PMU.
The current code was wrongly relying on the EVENT_ATTR_STR()
macro which uses the events_sysfs_show() function in the x86
PMU code. That function itself was relying on the x86_pmu data
structure. Yet RAPL and the core PMU (x86_pmu) have nothing to
do with each other. They should therefore not interact with
each other.
The x86_pmu structure is initialized at boot time based on
the host CPU model. When the host CPU is not supported, the
x86_pmu remains uninitialized and some of the callbacks it
contains are NULL.
The false dependency with x86_pmu could potentially cause crashes
in case the x86_pmu is not initialized while the RAPL PMU is. This
may, for instance, be the case in virtualized environments.
This patch fixes the problem by using a private sysfs_show()
routine for exporting the RAPL PMU events.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150113225953.GA21525@thinkpad
Cc: vincent.weaver@maine.edu
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>
If the function graph tracer traces a jprobe callback, the system will
crash. This can easily be demonstrated by compiling the jprobe
sample module that is in the kernel tree, loading it and running the
function graph tracer.
# modprobe jprobe_example.ko
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# ls
The first two commands end up in a nice crash after the first fork.
(do_fork has a jprobe attached to it, so "ls" just triggers that fork)
The problem is caused by the jprobe_return() that all jprobe callbacks
must end with. The way jprobes works is that the function a jprobe
is attached to has a breakpoint placed at the start of it (or it uses
ftrace if fentry is supported). The breakpoint handler (or ftrace callback)
will copy the stack frame and change the ip address to return to the
jprobe handler instead of the function. The jprobe handler must end
with jprobe_return() which swaps the stack and does an int3 (breakpoint).
This breakpoint handler will then put back the saved stack frame,
simulate the instruction at the beginning of the function it added
a breakpoint to, and then continue on.
For function tracing to work, it hijakes the return address from the
stack frame, and replaces it with a hook function that will trace
the end of the call. This hook function will restore the return
address of the function call.
If the function tracer traces the jprobe handler, the hook function
for that handler will not be called, and its saved return address
will be used for the next function. This will result in a kernel crash.
To solve this, pause function tracing before the jprobe handler is called
and unpause it before it returns back to the function it probed.
Some other updates:
Used a variable "saved_sp" to hold kcb->jprobe_saved_sp. This makes the
code look a bit cleaner and easier to understand (various tries to fix
this bug required this change).
Note, if fentry is being used, jprobes will change the ip address before
the function graph tracer runs and it will not be able to trace the
function that the jprobe is probing.
Link: http://lkml.kernel.org/r/20150114154329.552437962@goodmis.org
Cc: stable@vger.kernel.org # 2.6.30+
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
and a cleanup from me.
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Merge tag 'ras_for_3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/ras
Pull RAS updates from Borislav Petkov:
"Nothing special this time, just an error messages improvement from Andy
and a cleanup from me."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Simplify irq_remapping code by killing irq_remapping_supported() and
related interfaces.
Joerg posted a similar patch at https://lkml.org/lkml/2014/12/15/490,
so assume an signed-off from Joerg.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When interrupt remapping hardware is not in X2APIC, CPU X2APIC mode
will be disabled if:
1) Maximum CPU APIC ID is bigger than 255
2) hypervisior doesn't support x2apic mode.
But we should only check whether hypervisor supports X2APIC mode when
hypervisor(CONFIG_HYPERVISOR_GUEST) is enabled, otherwise X2APIC will
always be disabled when CONFIG_HYPERVISOR_GUEST is disabled and IR
doesn't work in X2APIC mode.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Tested-by: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-12-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If remapping is in XAPIC mode, the setup code just skips X2APIC
initialization without checking max CPU APIC ID in system, which may
cause problem if system has a CPU with APIC ID bigger than 255.
Handle IR in XAPIC mode the same way as if remapping is disabled.
[ tglx: Split out from previous patch ]
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-8-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Refine enable_IR_x2apic() and related functions for better readability.
[ tglx: Removed the XAPIC mode change and split it out into a seperate
patch. Added comments. ]
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-8-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
X2APIC will be disabled if user specifies "nox2apic" on kernel command
line, even when x2apic_preenabled is true. So correctly detect X2APIC
status by using x2apic_enabled() instead of x2apic_preenabled.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-7-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Local variable x2apic_enabled has been assigned to but never referred,
so kill it.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-6-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When kernel doesn't support X2APIC but BIOS has enabled X2APIC, system
may panic or hang without useful messages. On the other hand, it's
hard to dynamically disable X2APIC when CONFIG_X86_X2APIC is disabled.
So panic with a clear message in such a case.
Now system panics as below when X2APIC is disabled and interrupt remapping
is enabled:
[ 0.316118] LAPIC pending interrupts after 512 EOI
[ 0.322126] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
[ 0.368655] Kernel panic - not syncing: timer doesn't work through Interrupt-remapped IO-APIC
[ 0.378300] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.18.0+ #340
[ 0.385300] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRIVTIN1.86B.0051.L05.1406240953 06/24/2014
[ 0.396997] ffff88046dc03000 ffff88046c307dd8 ffffffff8179dada 00000000000043f2
[ 0.405629] ffffffff81a92158 ffff88046c307e58 ffffffff8179b757 0000000000000002
[ 0.414261] 0000000000000008 ffff88046c307e68 ffff88046c307e08 ffffffff813ad82b
[ 0.422890] Call Trace:
[ 0.425711] [<ffffffff8179dada>] dump_stack+0x45/0x57
[ 0.431533] [<ffffffff8179b757>] panic+0xc1/0x1f5
[ 0.436978] [<ffffffff813ad82b>] ? delay_tsc+0x3b/0x70
[ 0.442910] [<ffffffff8166fa2c>] panic_if_irq_remap+0x1c/0x20
[ 0.449524] [<ffffffff81d73645>] setup_IO_APIC+0x405/0x82e
[ 0.464979] [<ffffffff81d6fcc2>] native_smp_prepare_cpus+0x2d9/0x31c
[ 0.472274] [<ffffffff81d5d0ac>] kernel_init_freeable+0xd6/0x223
[ 0.479170] [<ffffffff81792ad0>] ? rest_init+0x80/0x80
[ 0.485099] [<ffffffff81792ade>] kernel_init+0xe/0xf0
[ 0.490932] [<ffffffff817a537c>] ret_from_fork+0x7c/0xb0
[ 0.497054] [<ffffffff81792ad0>] ? rest_init+0x80/0x80
[ 0.502983] ---[ end Kernel panic - not syncing: timer doesn't work through Interrupt-remapped IO-APIC
System hangs as below when X2APIC and interrupt remapping are both disabled:
[ 1.102782] pci 0000:00:02.0: System wakeup disabled by ACPI
[ 1.109351] pci 0000:00:03.0: System wakeup disabled by ACPI
[ 1.115915] pci 0000:00:03.2: System wakeup disabled by ACPI
[ 1.122479] pci 0000:00:03.3: System wakeup disabled by ACPI
[ 1.132274] pci 0000:00:1c.0: Enabling MPC IRBNCE
[ 1.137620] pci 0000:00:1c.0: Intel PCH root port ACS workaround enabled
[ 1.145239] pci 0000:00:1c.0: System wakeup disabled by ACPI
[ 1.151790] pci 0000:00:1c.7: Enabling MPC IRBNCE
[ 1.157128] pci 0000:00:1c.7: Intel PCH root port ACS workaround enabled
[ 1.164748] pci 0000:00:1c.7: System wakeup disabled by ACPI
[ 1.171447] pci 0000:00:1e.0: System wakeup disabled by ACPI
[ 1.178612] acpiphp: Slot [8] registered
[ 1.183095] pci 0000:00:02.0: PCI bridge to [bus 01]
[ 1.188867] acpiphp: Slot [2] registered
With this patch applied, the system panics in both cases with a proper
panic message.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1420615903-28253-5-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If x2apic got disabled on the kernel command line, then the following
issue can happen:
enable_IR_x2apic()
....
x2apic_mode = 1;
enable_x2apic();
if (x2apic_disabled) {
__disable_x2apic();
return;
}
That leaves X2APIC disabled in hardware, but x2apic_mode stays 1. So
all other code which checks x2apic_mode gets the wrong information.
Set x2apic_mode to 0 after disabling it in hardware.
This is just a hotfix. The proper solution is to rework this code so
it has seperate functions for the initial setup on the boot processor
and the secondary cpus, but that's beyond the scope of this fix.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
enable_IR_x2apic() calls setup_irq_remapping_ops() which by default
installs the intel dmar remapping ops and then calls the amd iommu irq
remapping prepare callback to figure out whether we are running on an
AMD machine with irq remapping hardware.
Right after that it calls irq_remapping_prepare() which pointlessly
checks:
if (!remap_ops || !remap_ops->prepare)
return -ENODEV;
and then calls
remap_ops->prepare()
which is silly in the AMD case as it got called from
setup_irq_remapping_ops() already a few microseconds ago.
Simplify this and just collapse everything into
irq_remapping_prepare().
The irq_remapping_prepare() remains still silly as it assigns blindly
the intel ops, but that's not scope of this patch.
The scope here is to move the preperatory work, i.e. memory
allocations out of the atomic section which is required to enable irq
remapping.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Acked-and-tested-by: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: Joerg Roedel <jroedel@suse.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Oren Twaig <oren@scalemp.com>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20141205084147.232633738@linutronix.de
Link: http://lkml.kernel.org/r/1420615903-28253-2-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No code changes.
This is a preparatory patch for change in "struct pt_regs" handling.
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Oleg Nesterov <oleg@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: X86 ML <x86@kernel.org>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: linux-kernel@vger.kernel.org
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
A define, two macros and an unreferenced bit of assembly are gone.
Acked-by: Borislav Petkov <bp@suse.de>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Oleg Nesterov <oleg@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: X86 ML <x86@kernel.org>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: linux-kernel@vger.kernel.org
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Pass the original kprobe for preparing an optimized kprobe arch-dep
part, since for some architecture (e.g. ARM32) requires the information
in original kprobe.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Pull x86 fixes from Ingo Molnar:
"Misc fixes: two vdso fixes, two kbuild fixes and a boot failure fix
with certain odd memory mappings"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, vdso: Use asm volatile in __getcpu
x86/build: Clean auto-generated processor feature files
x86: Fix mkcapflags.sh bash-ism
x86: Fix step size adjustment during initial memory mapping
x86_64, vdso: Fix the vdso address randomization algorithm
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, but also some kernel side fixes: uncore PMU
driver fix, user regs sampling fix and an instruction decoder fix that
unbreaks PEBS precise sampling"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/uncore/hsw-ep: Handle systems with only two SBOXes
perf/x86_64: Improve user regs sampling
perf: Move task_pt_regs sampling into arch code
x86: Fix off-by-one in instruction decoder
perf hists browser: Fix segfault when showing callchain
perf callchain: Free callchains when hist entries are deleted
perf hists: Fix children sort key behavior
perf diff: Fix to sort by baseline field by default
perf list: Fix --raw-dump option
perf probe: Fix crash in dwarf_getcfi_elf
perf probe: Fix to fall back to find probe point in symbols
perf callchain: Append callchains only when requested
perf ui/tui: Print backtrace symbols when segfault occurs
perf report: Show progress bar for output resorting
dmesg (from util-linux) currently has two methods for reading the kernel
message ring buffer: /dev/kmsg and syslog(2). Since kernel 3.5.0 kmsg
has been the default, which escapes control characters (e.g. new lines)
before they are shown.
This change means that when dmesg is using /dev/kmsg, a 2 line printk
makes the output messy, because the second line does not get a
timestamp.
For example:
[ 0.012863] CPU0: Thermal monitoring enabled (TM1)
[ 0.012869] Last level iTLB entries: 4KB 1024, 2MB 1024, 4MB 1024
Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 1024, 1GB 4
[ 0.012958] Freeing SMP alternatives memory: 28K (ffffffff81d86000 - ffffffff81d8d000)
[ 0.014961] dmar: Host address width 39
Because printk.c intentionally escapes control characters, they should
not be there in the first place. This patch fixes two occurrences of
this.
Signed-off-by: Steven Honeyman <stevenhoneyman@gmail.com>
Link: https://lkml.kernel.org/r/1414856696-8094-1-git-send-email-stevenhoneyman@gmail.com
[ Boris: make cpu_detect_tlb() static, while at it. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
There was another report of a boot failure with a #GP fault in the
uncore SBOX initialization. The earlier work around was not enough
for this system.
The boot was failing while trying to initialize the third SBOX.
This patch detects parts with only two SBOXes and limits the number
of SBOX units to two there.
Stable material, as it affects boot problems on 3.18.
Tested-by: Andreas Oehler <andreas@oehler-net.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Link: http://lkml.kernel.org/r/1420583675-9163-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Perf reports user regs for kernel-mode samples so that samples can
be backtraced through user code. The old code was very broken in
syscall context, resulting in useless backtraces.
The new code, in contrast, is still dangerously racy, but it should
at least work most of the time.
Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: chenggang.qcg@taobao.com
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/243560c26ff0f739978e2459e203f6515367634d.1420396372.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On x86_64, at least, task_pt_regs may be only partially initialized
in many contexts, so x86_64 should not use it without extra care
from interrupt context, let alone NMI context.
This will allow x86_64 to override the logic and will supply some
scratch space to use to make a cleaner copy of user regs.
Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: chenggang.qcg@taobao.com
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/e431cd4c18c2e1c44c774f10758527fb2d1025c4.1420396372.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We now switch to the kernel stack when a machine check interrupts
during user mode. This means that we can perform recovery actions
in the tail of do_machine_check()
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
acpi_map_lsapic() will allocate a logical CPU number and map it to
physical CPU id (such as APIC id) for the hot-added CPU, it will also
do some mapping for NUMA node id and etc, acpi_unmap_lsapic() will
do the reverse.
We can see that the name of the function is a little bit confusing and
arch (IA64) dependent so rename them as acpi_(un)map_cpu() to make arch
agnostic and explicit.
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In some IST handlers, if the interrupt came from user mode,
we can safely enable preemption. Add helpers to do it safely.
This is intended to be used my the memory failure code in
do_machine_check.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
There's no good reason for it to be a macro, and x86_64 will want to
use it, so it should be in a header.
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
We currently pretend that IST context is like standard exception
context, but this is incorrect. IST entries from userspace are like
standard exceptions except that they use per-cpu stacks, so they are
atomic. IST entries from kernel space are like NMIs from RCU's
perspective -- they are not quiescent states even if they
interrupted the kernel during a quiescent state.
Add and use ist_enter and ist_exit to track IST context. Even
though x86_32 has no IST stacks, we track these interrupts the same
way.
This fixes two issues:
- Scheduling from an IST interrupt handler will now warn. It would
previously appear to work as long as we got lucky and nothing
overwrote the stack frame. (I don't know of any bugs in this
that would trigger the warning, but it's good to be on the safe
side.)
- RCU handling in IST context was dangerous. As far as I know,
only machine checks were likely to trigger this, but it's good to
be on the safe side.
Note that the machine check handlers appears to have been missing
any context tracking at all before this patch.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
This causes all non-NMI, non-double-fault kernel entries from
userspace to run on the normal kernel stack. Double-fault is
exempt to minimize confusion if we double-fault directly from
userspace due to a bad kernel stack.
This is, suprisingly, simpler and shorter than the current code. It
removes the IMO rather frightening paranoid_userspace path, and it
make sync_regs much simpler.
There is no risk of stack overflow due to this change -- the kernel
stack that we switch to is empty.
This will also enable us to create non-atomic sections within
machine checks from userspace, which will simplify memory failure
handling. It will also allow the upcoming fsgsbase code to be
simplified, because it doesn't need to worry about usergs when
scheduling in paranoid_exit, as that code no longer exists.
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Commit 9def39be4e ("x86: Support compiling out human-friendly
processor feature names") made two source file targets
conditional. Such conditional targets will not be cleaned
automatically by make mrproper.
Fix by adding explicit clean-files targets for the two files.
Fixes: 9def39be4e ("x86: Support compiling out human-friendly processor feature names")
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Cc: Josh Triplett <josh@joshtriplett.org>
Link: http://lkml.kernel.org/r/1419335863-10608-1-git-send-email-bjorn@mork.no
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove the function is_apbt_capable() that is not used anywhere.
This was partially found by using a static code analysis program
called 'cppcheck'.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Reviewed-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1419166698-2470-1-git-send-email-rickard_strandqvist@spectrumdigital.se
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds