Commit graph

10243 commits

Author SHA1 Message Date
David Rientjes
e76661ba09 x86, apic: Remove multi_timer_check callback
Since commit b5660ba76b ("x86, platforms: Remove NUMAQ") removed NUMAQ,
the multi_timer_check() apic callback has been obsolete.  Remove it.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302351120.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:43 -07:00
David Rientjes
4c59f3e63d x86, apic: Replace noop_check_apicid_used
noop_check_apicid_used() has the same implementation as
default_check_apicid_used() in the standard header file, so replace the
former with the latter.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302350450.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:43 -07:00
David Rientjes
658ffd7e6f x86, apic: Remove check_apicid_present callback
The check_apicid_present() apic callback is never called, so remove it
and functions that implement it.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302350160.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:42 -07:00
David Rientjes
c460b5d340 x86, apic: Remove mps_oem_check callback
Since commit b5660ba76b ("x86, platforms: Remove NUMAQ") removed NUMAQ,
the mps_oem_check() apic callback has been obsolete.  Remove it.

This allows generic_mps_oem_check() to be removed as well.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302349390.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:42 -07:00
David Rientjes
300eddf967 x86, apic: Remove smp_callin_clear_local_apic callback
Since commit b5660ba76b ("x86, platforms: Remove NUMAQ") removed NUMAQ,
the smp_callin_clear_local_apic() apic callback has been obsolete.
Remove it.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302349040.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:41 -07:00
David Rientjes
6ab1b27c84 x86, apic: Replace trampoline physical addresses with defaults
The trampoline_phys_{high,low} members of struct apic are always
initialized to DEFAULT_TRAMPOLINE_PHYS_HIGH and TRAMPOLINE_PHYS_LOW,
respectively.  Hardwire the constants and remove the unneeded members.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302348330.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:41 -07:00
David Rientjes
80a2670379 x86, apic: Remove x86_32_numa_cpu_node callback
Since commit b5660ba76b ("x86, platforms: Remove NUMAQ") removed NUMAQ,
the x86_32_numa_cpu_node() apic callback has been obsolete.  Remove it.

Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302348060.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31 08:05:40 -07:00
H. Peter Anvin
c3107e3c50 APEI is currently implemented so that it depends on x86 hardware.
The primary dependency is that GHES uses the x86 NMI for hardware
 error notification and MCE for memory error handling. These patches
 remove that dependency.
 
 Other APEI features such as error reporting via external IRQ, error
 serialization, or error injection, do not require changes to use them
 on non-x86 architectures.
 
 The following patch set eliminates the APEI Kconfig x86 dependency
 by making these changes:
 - treat NMI notification as GHES architecture - HAVE_ACPI_APEI_NMI
 - group and wrap around #ifdef CONFIG_HAVE_ACPI_APEI_NMI code which
   is used only for NMI path
 - identify architectural boxes and abstract it accordingly (tlb flush and MCE)
 - rework ioremap for both IRQ and NMI context
 
 NMI code is kept in ghes.c file since NMI and IRQ context are tightly coupled.
 
 Note, these patches introduce no functional changes for x86. The NMI notification
 feature is hard selected for x86. Architectures that want to use this
 feature should also provide NMI code infrastructure.
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Merge tag 'please-pull-apei' into x86/ras

APEI is currently implemented so that it depends on x86 hardware.
The primary dependency is that GHES uses the x86 NMI for hardware
error notification and MCE for memory error handling. These patches
remove that dependency.

Other APEI features such as error reporting via external IRQ, error
serialization, or error injection, do not require changes to use them
on non-x86 architectures.

The following patch set eliminates the APEI Kconfig x86 dependency
by making these changes:
- treat NMI notification as GHES architecture - HAVE_ACPI_APEI_NMI
- group and wrap around #ifdef CONFIG_HAVE_ACPI_APEI_NMI code which
  is used only for NMI path
- identify architectural boxes and abstract it accordingly (tlb flush and MCE)
- rework ioremap for both IRQ and NMI context

NMI code is kept in ghes.c file since NMI and IRQ context are tightly coupled.

Note, these patches introduce no functional changes for x86. The NMI notification
feature is hard selected for x86. Architectures that want to use this
feature should also provide NMI code infrastructure.
2014-07-30 10:48:00 -07:00
Andy Lutomirski
7209a75d20 x86_64/entry/xen: Do not invoke espfix64 on Xen
This moves the espfix64 logic into native_iret.  To make this work,
it gets rid of the native patch for INTERRUPT_RETURN:
INTERRUPT_RETURN on native kernels is now 'jmp native_iret'.

This changes the 16-bit SS behavior on Xen from OOPSing to leaking
some bits of the Xen hypervisor's RSP (I think).

[ hpa: this is a nonzero cost on native, but probably not enough to
  measure. Xen needs to fix this in their own code, probably doing
  something equivalent to espfix64. ]

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/7b8f1d8ef6597cb16ae004a43c56980a7de3cf94.1406129132.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>
2014-07-28 15:25:40 -07:00
Ingo Molnar
5030c69755 Linux 3.16-rc7
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Merge tag 'v3.16-rc7' into perf/core, to merge in the latest fixes before applying new changes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-28 10:00:33 +02:00
Linus Torvalds
9dae0a3fc4 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A bunch of fixes for perf and kprobes:
   - revert a commit that caused a perf group regression
   - silence dmesg spam
   - fix kprobe probing errors on ia64 and ppc64
   - filter kprobe faults from userspace
   - lockdep fix for perf exit path
   - prevent perf #GP in KVM guest
   - correct perf event and filters"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kprobes: Fix "Failed to find blacklist" probing errors on ia64 and ppc64
  kprobes/x86: Don't try to resolve kprobe faults from userspace
  perf/x86/intel: Avoid spamming kernel log for BTS buffer failure
  perf/x86/intel: Protect LBR and extra_regs against KVM lying
  perf: Fix lockdep warning on process exit
  perf/x86/intel/uncore: Fix SNB-EP/IVT Cbox filter mappings
  perf/x86/intel: Use proper dTLB-load-misses event on IvyBridge
  perf: Revert ("perf: Always destroy groups on exit")
2014-07-27 09:57:16 -07:00
Andy Lutomirski
53b884ac37 x86_64/vsyscall: Fix warn_bad_vsyscall log output
This commit in Linux 3.6:

    commit c767a54ba0
    Author: Joe Perches <joe@perches.com>
    Date:   Mon May 21 19:50:07 2012 -0700

        x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>

caused warn_bad_vsyscall to output garbage in the middle of the
line.  Revert the bad part of it.

The printk in question isn't actually bare; the level is "%s".

The bug this fixes is purely cosmetic; backports are optional.

Cc: <stable@vger.kernel.org> # v3.6+
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/03eac1f24110bbe496ecc12a4df467e0d88466d4.1406330947.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-25 16:34:15 -07:00
Li, Aubrey
f855911c1f x86/pmc_atom: Expose PMC device state and platform sleep state
Add the following interfaces to exposes PMC device state and sleep
state residency via debugfs:
	/sys/kernel/debugfs/pmc_atom/dev_state
	/sys/kernel/debugfs/pmc_atom/sleep_state

Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Link: http://lkml.kernel.org/r/53B0FF59.8000600@linux.intel.com
Signed-off-by: Kasagar, Srinidhi <srinidhi.kasagar@intel.com>
Reviewed-by: Rudramuni, Vishwesh M <vishwesh.m.rudramuni@intel.com>
Reviewed-by: Joe Perches <joe@perches.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-25 14:12:14 -07:00
Li, Aubrey
b00055cade x86/pmc_atom: Eisable a few S0ix wake up events for S0ix residency
Disable PMC S0IX_WAKE_EN events coming from LPC block(unused) and
also from GPIO_SUS ored dedicated IRQs (must be disabled as per PMC
programming rule), GPIOSCORE ored dedicated IRQs (must be disabled
as per PMC programming rule), GPIO_SUS shared IRQ (not necessary
since the IOAPIC_DS wake event will still work), GPIO_SCORE shared
IRQ (not necessary since the IOAPIC_DS wake event will still work).

Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Link: http://lkml.kernel.org/r/53B0FF22.5080403@linux.intel.com
Signed-off-by: Olivier Leveque <olivier.leveque@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-25 14:11:58 -07:00
Li, Aubrey
93e5eadd1f x86/platform: New Intel Atom SOC power management controller driver
The Power Management Controller (PMC) controls many of the power
management features present in the Atom SoC. This driver provides
a native power off function via PMC PCI IO port.

On some ACPI hardware-reduced platforms(e.g. ASUS-T100), ACPI sleep
registers are not valid so that (*pm_power_off)() is not hooked by
acpi_power_off(). The power off function in this driver is installed
only when pm_power_off is NULL.

Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Link: http://lkml.kernel.org/r/53B0FEEA.3010805@linux.intel.com
Signed-off-by: Lejun Zhu <lejun.zhu@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-25 14:11:29 -07:00
Henrique de Moraes Holschuh
532ed3740c x86, microcode, intel: Rename apply_microcode and declare it static
Rename apply_microcode() in microcode/intel.c to
apply_microcode_intel(), and declare it as static. This is a cosmetic
fix to silence a warning issued by sparse.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: http://lkml.kernel.org/r/1406146251-8540-1-git-send-email-hmh@hmh.eng.br
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-07-25 17:57:51 +02:00
H. Peter Anvin
bf72f5dee0 Promote one fix for 3.16
This fix was necessary after
 
 9c15a24b03 ("x86/mce: Improve mcheck_init_device() error handling")
 
 went in. What this patch did was, among others, check the return value
 of misc_register and exit early if it encountered an error. Original
 code sloppily didn't do that.
 
 However,
 
         cef12ee52b ("xen/mce: Add mcelog support for Xen platform")
 
 made it so that xen's init routine xen_late_init_mcelog runs first. This
 was needed for the xen mcelog device which is supposed to be independent
 from the baremetal one.
 
 Initially it was reported that misc_register() fails often on xen and
 that's why it needed fixing. However, it is *supposed* to fail by
 design, when running in dom0 so that the xen mcelog device file gets
 registered first.
 
 And *then* you need the notifier *not* unregistered on the error path so
 that the timer does get deleted properly in the CPU hotplug notifier.
 
 Btw, this fix is needed also on baremetal in the unlikely event that
 misc_register(&mce_chrdev_device) fails there too.
 
 I was unsure whether to rush it in now and decided to delay it to 3.17.
 However, xen people wanted it promoted as it breaks xen when doing cpu
 hotplug there. So, after a bit of simmering in tip/master for initial
 smoke testing, let's move it to 3.16. It fixes a semi-regression which
 got introduced in 3.16 so no need for stable tagging.
 
 tip/x86/ras contains that exact same commit but we can't remove it
 there as it is not the last one. It won't cause any merge issues, as I
 confirmed locally but I should state here the special situation of this
 one fix explicitly anyway.
 
 Thanks.
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x86: Merge tag 'ras_urgent' into x86/urgent

Promote one fix for 3.16

This fix was necessary after

9c15a24b03 ("x86/mce: Improve mcheck_init_device() error handling")

went in. What this patch did was, among others, check the return value
of misc_register and exit early if it encountered an error. Original
code sloppily didn't do that.

However,

        cef12ee52b ("xen/mce: Add mcelog support for Xen platform")

made it so that xen's init routine xen_late_init_mcelog runs first. This
was needed for the xen mcelog device which is supposed to be independent
from the baremetal one.

Initially it was reported that misc_register() fails often on xen and
that's why it needed fixing. However, it is *supposed* to fail by
design, when running in dom0 so that the xen mcelog device file gets
registered first.

And *then* you need the notifier *not* unregistered on the error path so
that the timer does get deleted properly in the CPU hotplug notifier.

Btw, this fix is needed also on baremetal in the unlikely event that
misc_register(&mce_chrdev_device) fails there too.

I was unsure whether to rush it in now and decided to delay it to 3.17.
However, xen people wanted it promoted as it breaks xen when doing cpu
hotplug there. So, after a bit of simmering in tip/master for initial
smoke testing, let's move it to 3.16. It fixes a semi-regression which
got introduced in 3.16 so no need for stable tagging.

tip/x86/ras contains that exact same commit but we can't remove it
there as it is not the last one. It won't cause any merge issues, as I
confirmed locally but I should state here the special situation of this
one fix explicitly anyway.

Thanks.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-24 16:32:31 -07:00
Henrique de Moraes Holschuh
f99b45c3c2 x86, microcode, intel: Fix typos
Fix some typos. One of them was in a struct name, fortunately harmless
because it happened on a "sizeof(struct foo*)" construction.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: http://lkml.kernel.org/r/1406146251-8540-1-git-send-email-hmh@hmh.eng.br
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-07-24 12:32:49 +02:00
Henrique de Moraes Holschuh
05a5f76d03 x86, microcode, intel: Add missing static declarations
gcc reports that a few declarations are missing.
Fix two obvious ones.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: http://lkml.kernel.org/r/1406146251-8540-1-git-send-email-hmh@hmh.eng.br
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-07-24 12:26:52 +02:00
Henrique de Moraes Holschuh
1d2ce978d1 x86, microcode, amd: Fix missing static declaration
Make locally used variable static.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: http://lkml.kernel.org/r/1406146251-8540-1-git-send-email-hmh@hmh.eng.br
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-07-24 12:21:46 +02:00
Thomas Gleixner
d28ede8379 timekeeping: Create struct tk_read_base and use it in struct timekeeper
The members of the new struct are the required ones for the new NMI
safe accessor to clcok monotonic. In order to reuse the existing
timekeeping code and to make the update of the fast NMI safe
timekeepers a simple memcpy use the struct for the timekeeper as well
and convert all users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23 15:01:53 -07:00
Thomas Gleixner
4a0e637738 clocksource: Get rid of cycle_last
cycle_last was added to the clocksource to support the TSC
validation. We moved that to the core code, so we can get rid of the
extra copy.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23 15:01:52 -07:00
Thomas Gleixner
09ec54429c clocksource: Move cycle_last validation to core code
The only user of the cycle_last validation is the x86 TSC. In order to
provide NMI safe accessor functions for clock monotonic and
monotonic_raw we need to do that in the core.

We can't do the TSC specific

    if (now < cycle_last)
       	    now = cycle_last;

for the other wrapping around clocksources, but TSC has
CLOCKSOURCE_MASK(64) which actually does not mask out anything so if
now is less than cycle_last the subtraction will give a negative
result. So we can check for that in clocksource_delta() and return 0
for that case.

Implement and enable it for x86

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23 15:01:51 -07:00
Peter Zijlstra
2a2261553d x86, cpu: Fix cache topology for early P4-SMT
P4 systems with cpuid level < 4 can have SMT, but the cache topology
description available (cpuid2) does not include SMP information.

Now we know that SMT shares all cache levels, and therefore we can
mark all available cache levels as shared.

We do this by setting cpu_llc_id to ->phys_proc_id, since that's
the same for each SMT thread. We can do this unconditional since if
there's no SMT its still true, the one CPU shares cache with only
itself.

This fixes a problem where such CPUs report an incorrect LLC CPU mask.

This in turn fixes a crash in the scheduler where the topology was
build wrong, it assumes the LLC mask to include at least the SMT CPUs.

Cc: Josh Boyer <jwboyer@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Bruno Wolff III <bruno@wolff.to>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140722133514.GM12054@laptop.lan
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-23 08:16:17 -07:00
Tomasz Nowicki
594c7255dc acpi, apei, ghes: Factor out ioremap virtual memory for IRQ and NMI context.
GHES currently maps two pages with atomic_ioremap.  From now
on, NMI is architectural depended so there is no need to allocate
an NMI page for platforms without NMI support.

To make it possible to not use a second page, swap the existing
page order so that the IRQ context page is first, and the optional
NMI context page is second.  Then, use HAVE_ACPI_APEI_NMI to decide
how many pages are to be allocated.

Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-07-22 15:05:06 -07:00
Tomasz Nowicki
9dae3d0d9e apei, mce: Factor out APEI architecture specific MCE calls.
This commit abstracts MCE calls and provides weak corresponding default
implementation for those architectures which do not need arch specific
actions. Each platform willing to do additional architectural actions
should provides desired function definition. It allows us to avoid wrap
code into #ifdef in generic code and prevent new platform from introducing
dummy stub function too.

Initially, there are two APEI arch-specific calls:
- arch_apei_enable_cmcff()
- arch_apei_report_mem_error()
Both interact with MCE driver for X86 architecture.

Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-07-22 15:05:06 -07:00
Sven Wegener
8142b21550 x86_32, entry: Store badsys error code in %eax
Commit 554086d ("x86_32, entry: Do syscall exit work on badsys
(CVE-2014-4508)") introduced a regression in the x86_32 syscall entry
code, resulting in syscall() not returning proper errors for undefined
syscalls on CPUs supporting the sysenter feature.

The following code:

> int result = syscall(666);
> printf("result=%d errno=%d error=%s\n", result, errno, strerror(errno));

results in:

> result=666 errno=0 error=Success

Obviously, the syscall return value is the called syscall number, but it
should have been an ENOSYS error. When run under ptrace it behaves
correctly, which makes it hard to debug in the wild:

> result=-1 errno=38 error=Function not implemented

The %eax register is the return value register. For debugging via ptrace
the syscall entry code stores the complete register context on the
stack. The badsys handlers only store the ENOSYS error code in the
ptrace register set and do not set %eax like a regular syscall handler
would. The old resume_userspace call chain contains code that clobbers
%eax and it restores %eax from the ptrace registers afterwards. The same
goes for the ptrace-enabled call chain. When ptrace is not used, the
syscall return value is the passed-in syscall number from the untouched
%eax register.

Use %eax as the return value register in syscall_badsys and
sysenter_badsys, like a real syscall handler does, and have the caller
push the value onto the stack for ptrace access.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Link: http://lkml.kernel.org/r/alpine.LNX.2.11.1407221022380.31021@titan.int.lan.stealer.net
Reviewed-and-tested-by: Andy Lutomirski <luto@amacapital.net>
Cc: <stable@vger.kernel.org> # If 554086d is backported
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-22 02:34:05 -07:00
Borislav Petkov
51cbe7e7c4 x86, MCE: Robustify mcheck_init_device
BorisO reports that misc_register() fails often on xen. The current code
unregisters the CPU hotplug notifier in that case. If then a CPU is
offlined and onlined back again, we end up with a second timer running
on that CPU, leading to soft lockups and system hangs.

So let's leave the hotcpu notifier always registered - even if
mce_device_create failed for some cores and never unreg it so that we
can deal with the timer handling accordingly.

Reported-and-Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1403274493-1371-1-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Borislav Petkov <bp@suse.de>
2014-07-21 18:14:32 +02:00
Linus Torvalds
1b9f0efd61 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "A couple of key fixes and a few less critical ones.  The main ones
  are:

   - add a .bss section to the PE/COFF headers when building with EFI
     stub

   - invoke the correct paravirt magic when building the espfix page
     tables

  Unfortunately both of these areas also have at least one additional
  fix each still in thie pipeline, but which are not yet ready to push"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Remove unused variable "polling"
  x86/espfix/xen: Fix allocation of pages for paravirt page tables
  x86/efi: Include a .bss section within the PE/COFF headers
  efi: fdt: Do not report an error during boot if UEFI is not available
  efi/arm64: efistub: remove local copy of linux_banner
2014-07-18 20:46:55 -10:00
Daniel Kiper
9402973d49 arch/x86: Replace plain strings with constants
We've got constants, so let's use them instead of hard-coded values.

Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-07-18 21:23:59 +01:00
Matt Fleming
44be28e9dd x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag
It appears that the BayTrail-T class of hardware requires EFI in order
to powerdown and reboot and no other reliable method exists.

This quirk is generally applicable to all hardware that has the ACPI
Hardware Reduced bit set, since usually ACPI would be the preferred
method.

Cc: Len Brown <len.brown@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-07-18 21:23:52 +01:00
Matt Fleming
8562c99cdd efi/reboot: Add generic wrapper around EfiResetSystem()
Implement efi_reboot(), which is really just a wrapper around the
EfiResetSystem() EFI runtime service, but it does at least allow us to
funnel all callers through a single location.

It also simplifies the callsites since users no longer need to check to
see whether EFI_RUNTIME_SERVICES are enabled.

Cc: Tony Luck <tony.luck@intel.com>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-07-18 21:23:51 +01:00
Steven Rostedt (Red Hat)
fdc841b58c ftrace: x86: Remove check of obsolete variable function_trace_stop
Nothing sets function_trace_stop to disable function tracing anymore.
Remove the check for it in the arch code.

Link: http://lkml.kernel.org/r/53C54D32.6000000@zytor.com

Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-07-18 13:57:02 -04:00
Steven Rostedt (Red Hat)
84b2bc7fa0 ftrace/x86: Add call to ftrace_graph_is_dead() in function graph code
ftrace_stop() is going away as it disables parts of function tracing
that affects users that should not be affected. But ftrace_graph_stop()
is built on ftrace_stop(). Here's another example of killing all of
function tracing because something went wrong with function graph
tracing.

Instead of disabling all users of function tracing on function graph
error, disable only function graph tracing. To do this, the arch code
must call ftrace_graph_is_dead() before it implements function graph.

Link: http://lkml.kernel.org/r/53C54D18.3020602@zytor.com

Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-07-17 09:45:08 -04:00
Linus Torvalds
bcf44bfe5e Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "A cpufreq lockup fix and a compiler warning fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix compiler warnings
  x86, tsc: Fix cpufreq lockup
2014-07-16 10:11:02 -10:00
Linus Torvalds
d14aef3872 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Tooling fixes and an Intel PMU driver fixlet"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Do not allow optimized switch for non-cloned events
  perf/x86/intel: ignore CondChgd bit to avoid false NMI handling
  perf symbols: Get kernel start address by symbol name
  perf tools: Fix segfault in cumulative.callchain report
2014-07-16 10:10:27 -10:00
Christoph Schulz
cbace46a97 x86: don't exclude low BIOS area when allocating address space for non-PCI cards
Commit 30919b0bf3 ("x86: avoid low BIOS area when allocating address
space") moved the test for resource allocations that fall within the first
1MB of address space from the PCI-specific path to a generic path, such
that all resource allocations will avoid this area.  However, this breaks
ISA cards which need to allocate a memory region within the first 1MB.  An
example is the i82365 PCMCIA controller and derivatives like the Ricoh
RF5C296/396 which map part of the PCMCIA socket memory address space into
the first 1MB of system memory address space.  They do not work anymore as
no usable memory region exists due to this change:

  Intel ISA PCIC probe: Ricoh RF5C296/396 ISA-to-PCMCIA at port 0x3e0 ofs 0x00, 2 sockets
  host opts [0]: none
  host opts [1]: none
  ISA irqs (scanned) = 3,4,5,9,10 status change on irq 10
  pcmcia_socket pcmcia_socket1: pccard: PCMCIA card inserted into slot 1
  pcmcia_socket pcmcia_socket0: cs: IO port probe 0xc00-0xcff: excluding 0xcf8-0xcff
  pcmcia_socket pcmcia_socket0: cs: IO port probe 0xa00-0xaff: clean.
  pcmcia_socket pcmcia_socket0: cs: IO port probe 0x100-0x3ff: excluding 0x170-0x177 0x1f0-0x1f7 0x2f8-0x2ff 0x370-0x37f 0x3c0-0x3e7 0x3f0-0x3ff
  pcmcia_socket pcmcia_socket0: cs: memory probe 0x0a0000-0x0affff: excluding 0xa0000-0xaffff
  pcmcia_socket pcmcia_socket0: cs: memory probe 0x0b0000-0x0bffff: excluding 0xb0000-0xbffff
  pcmcia_socket pcmcia_socket0: cs: memory probe 0x0c0000-0x0cffff: excluding 0xc0000-0xcbfff
  pcmcia_socket pcmcia_socket0: cs: memory probe 0x0d0000-0x0dffff: clean.
  pcmcia_socket pcmcia_socket0: cs: memory probe 0x0e0000-0x0effff: clean.
  pcmcia_socket pcmcia_socket0: cs: memory probe 0x60000000-0x60ffffff: clean.
  pcmcia_socket pcmcia_socket0: cs: memory probe 0xa0000000-0xa0ffffff: clean.
  pcmcia_socket pcmcia_socket1: cs: IO port probe 0xc00-0xcff: excluding 0xcf8-0xcff
  pcmcia_socket pcmcia_socket1: cs: IO port probe 0xa00-0xaff: clean.
  pcmcia_socket pcmcia_socket1: cs: IO port probe 0x100-0x3ff: excluding 0x170-0x177 0x1f0-0x1f7 0x2f8-0x2ff 0x370-0x37f 0x3c0-0x3e7 0x3f0-0x3ff
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x0a0000-0x0affff: excluding 0xa0000-0xaffff
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x0b0000-0x0bffff: excluding 0xb0000-0xbffff
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x0c0000-0x0cffff: excluding 0xc0000-0xcbfff
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x0d0000-0x0dffff: clean.
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x0e0000-0x0effff: clean.
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x60000000-0x60ffffff: clean.
  pcmcia_socket pcmcia_socket1: cs: memory probe 0xa0000000-0xa0ffffff: clean.
  pcmcia_socket pcmcia_socket1: cs: memory probe 0x0cc000-0x0effff: excluding 0xe0000-0xeffff
  pcmcia_socket pcmcia_socket1: cs: unable to map card memory!

If filtering out the first 1MB is reverted, everything works as expected.

Tested-by: Robert Resch <fli4l@robert.reschpara.de>
Signed-off-by: Christoph Schulz <develop@kristov.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v2.6.37+
2014-07-16 12:29:36 -06:00
Jan Beulich
3bab13b015 x86/debug: Drop several unnecessary CFI annotations
With the conversion of the register saving code from macros to
functions, and with those functions not clobbering most of the
registers they spill, there's no need to annotate most of the
spill operations; the only exceptions being %rbx (always
modified) and %rcx (modified on the error_kernelspace: path).

Also remove a bogus commented out annotation - there's no
register %orig_rax after all.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/53AAE69A020000780001D3C7@mail.emea.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 15:23:06 +02:00
Andy Lutomirski
0cdd192cf4 kprobes/x86: Don't try to resolve kprobe faults from userspace
This commit:

    commit 6f6343f53d
    Author: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
    Date:   Thu Apr 17 17:17:33 2014 +0900

        kprobes/x86: Call exception handlers directly from do_int3/do_debug

appears to have inadvertently dropped a check that the int3 came
from kernel mode.  Trying to dereference addr when addr is
user-controlled is completely bogus.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/c4e339882c121aa76254f2adde3fcbdf502faec2.1405099506.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 14:16:32 +02:00
David Rientjes
4485154138 perf/x86/intel: Avoid spamming kernel log for BTS buffer failure
It's unnecessary to excessively spam the kernel log anytime the BTS buffer
cannot be allocated, so make this allocation __GFP_NOWARN.

The user probably will want to at least find some artifact that the
allocation has failed in the past, probably due to fragmentation because
of its large size, when it's not allocated at bootstrap.  Thus, add a
WARN_ONCE() so something is left behind for them to understand why perf
commnads that require PEBS is not working properly.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1406301600460.26302@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:31:30 +02:00
Zhouyi Zhou
503d3291a9 perf/x86/amd: Try to fix some mem allocation failure handling
According to Peter's advice, put the failure handling to a goto chain.
Compiled in x86_64, could you check if there is anything that I missed.

Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1402459743-20513-1-git-send-email-zhouzhouyi@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:31:06 +02:00
Kan Liang
338b522ca4 perf/x86/intel: Protect LBR and extra_regs against KVM lying
With -cpu host, KVM reports LBR and extra_regs support, if the host has
support.

When the guest perf driver tries to access LBR or extra_regs MSR,
it #GPs all MSR accesses,since KVM doesn't handle LBR and extra_regs support.
So check the related MSRs access right once at initialization time to avoid
the error access at runtime.

For reproducing the issue, please build the kernel with CONFIG_KVM_INTEL = y
(for host kernel).
And CONFIG_PARAVIRT = n and CONFIG_KVM_GUEST = n (for guest kernel).
Start the guest with -cpu host.
Run perf record with --branch-any or --branch-filter in guest to trigger LBR
Run perf stat offcore events (E.g. LLC-loads/LLC-load-misses ...) in guest to
trigger offcore_rsp #GP

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com>
Cc: Mark Davies <junk@eslaf.co.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Link: http://lkml.kernel.org/r/1405365957-20202-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:18:43 +02:00
Stephane Eranian
7711fe4fc2 perf/x86/intel/uncore: Fix SNB-EP/IVT Cbox filter mappings
This patch fixes the SNB-EP and IVT Cbox filter mapping
table. The table controls which filters are supported by
which events. There were several mistakes in those tables
causing some filters to be ignored, such as NID on
TOR_INSERTS.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: zheng.z.yan@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140630144624.GA2604@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:18:41 +02:00
Vince Weaver
1996388e9f perf/x86/intel: Use proper dTLB-load-misses event on IvyBridge
This was discussed back in February:

	https://lkml.org/lkml/2014/2/18/956

But I never saw a patch come out of it.

On IvyBridge we share the SandyBridge cache event tables, but the
dTLB-load-miss event is not compatible.  Patch it up after
the fact to the proper DTLB_LOAD_MISSES.DEMAND_LD_MISS_CAUSES_A_WALK

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1407141528200.17214@vincent-weaver-1.umelst.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:18:40 +02:00
Paul Bolle
d3f44fbabe x86: Remove unused variable "polling"
Compile tested. "polling" is unused since commit f80c5b39b8
("sched/idle, x86: Switch from TS_POLLING to TIF_POLLING_NRFLAG").

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Link: http://lkml.kernel.org/r/1404138749.2978.6.camel@x41
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 12:58:47 +02:00
Boris Ostrovsky
8762e50928 x86/espfix/xen: Fix allocation of pages for paravirt page tables
init_espfix_ap() is currently off by one level when informing hypervisor
that allocated pages will be used for ministacks' page tables.

The most immediate effect of this on a PV guest is that if
'stack_page = __get_free_page()' returns a non-zeroed-out page the hypervisor
will refuse to use it for a page table (which it shouldn't be anyway). This will
result in warnings by both Xen and Linux.

More importantly, a subsequent write to that page (again, by a PV guest) is
likely to result in fatal page fault.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1404926298-5565-1-git-send-email-boris.ostrovsky@oracle.com
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>
2014-07-14 13:47:32 -07:00
Borislav Petkov
26bfa5f894 x86, amd: Cleanup init_amd
Distribute family-specific code to corresponding functions.

Also,

* move the direct mapping splitting around the TSEG SMM area to
bsp_init_amd().

* kill ancient comment about what we should do for K5.

* merge amd_k7_smp_check() into its only caller init_amd_k7 and drop
cpu_has_mp macro.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1403609105-8332-3-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-14 12:21:40 -07:00
Borislav Petkov
80a208bd39 x86/cpufeature: Add bug flags to /proc/cpuinfo
Dump the flags which denote we have detected and/or have applied bug
workarounds to the CPU we're executing on, in a similar manner to the
feature flags.

The advantage is that those are not accumulating over time like the CPU
features.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1403609105-8332-2-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-14 12:21:39 -07:00
Oren Twaig
411cf9ee29 x86, vsmp: Remove is_vsmp_box() from apic_is_clustered_box()
When a vSMP Foundation box is detected, the function apic_cluster_num() counts
the number of APIC clusters found. If more than one found, a multi board
configuration is assumed, and TSC marked as unstable. This behavior is
incorrect as vSMP Foundation may use processors from single node only, attached
to memory of other nodes - and such node may have more than one APIC cluster
(typically any recent intel box has more than single APIC_CLUSTERID(x)).

To fix this, we simply remove the code which detects a vSMP Foundation box and
affects apic_is_clusted_box() return value. This can be done because later the
kernel checks by itself if the TSC is stable using the
check_tsc_sync_[source|target]() functions and marks TSC as unstable if needed.

Acked-by: Shai Fultheim <shai@scalemp.com>
Signed-off-by: Oren Twaig <oren@scalemp.com>
Link: http://lkml.kernel.org/r/1404036068-11674-1-git-send-email-oren@scalemp.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-13 17:48:03 -07:00
Borislav Petkov
b08ee5f7e4 x86: Simplify __HAVE_ARCH_CMPXCHG tests
Both the 32-bit and 64-bit cmpxchg.h header define __HAVE_ARCH_CMPXCHG
and there's ifdeffery which checks it. But since both bitness define it,
we can just as well move it up to the main cmpxchg header and simpify a
bit of code in doing that.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20140711104338.GB17083@pd.tnic
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 17:28:51 -07:00