linux.git/arch/x86/kernel/cpu, branch v4.12

x86/intel_rdt: Fix memory leak on mount failure

2017-06-30T19:20:00+00:00

If mount fails, the kn_info directory is not freed causing memory leak.

Add the missing error handling path.

Fixes: 4e978d06dedb ("x86/intel_rdt: Add "info" files to resctrl file system")
Signed-off-by: Vikas Shivappa 
Signed-off-by: Thomas Gleixner 
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: vikas.shivappa@intel.com
Cc: andi.kleen@intel.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1498503368-20173-3-git-send-email-vikas.shivappa@linux.intel.com

x86/microcode/intel: Clear patch pointer before jettisoning the initrd

2017-06-08T08:03:05+00:00

During early boot, load_ucode_intel_ap() uses __load_ucode_intel()
to obtain a pointer to the relevant microcode patch (embedded in the
initrd), and stores this value in 'intel_ucode_patch' to speed up the
microcode patch application for subsequent CPUs.

On resuming from suspend-to-RAM, however, load_ucode_ap() calls
load_ucode_intel_ap() for each non-boot-CPU. By then the initramfs is
long gone so the pointer stored in 'intel_ucode_patch' no longer points to
a valid microcode patch.

Clear that pointer so that we effectively fall back to the CPU hotplug
notifier callbacks to update the microcode.

Signed-off-by: Dominik Brodowski 
[ Edit and massage commit message. ]
Signed-off-by: Borislav Petkov 
Cc:  # 4.10..
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20170607095819.9754-1-bp@alien8.de
Signed-off-by: Ingo Molnar

x86/cpu/cyrix: Add alternative Device ID of Geode GX1 SoC

2017-06-05T06:34:20+00:00

A SoC variant of Geode GX1, notably NSC branded SC1100, seems to
report an inverted Device ID in its DIR0 configuration register,
specifically 0xb instead of the expected 0x4.

Catch this presumably quirky version so it's properly recognized
as GX1 and has its cache switched to write-back mode, which provides
a significant performance boost in most workloads.

SC1100's datasheet "Geode™ SC1100 Information Appliance On a Chip",
states in section 1.1.7.1 "Device ID" that device identification
values are specified in SC1100's device errata. These, however,
seem to not have been publicly released.

Wading through a number of boot logs and /proc/cpuinfo dumps found on
pastebin and blogs, this patch should mostly be relevant for a number
of now admittedly aging Soekris NET4801 and PC Engines WRAP devices,
the latter being the platform this issue was discovered on.
Performance impact was verified using "openssl speed", with
write-back caching scaling throughput between -3% and +41%.

Signed-off-by: Christian Sünkenberg 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1496596719.26725.14.camel@student.kit.edu
Signed-off-by: Ingo Molnar

x86/microcode/AMD: Change load_microcode_amd()'s param to bool to fix preemptibility bug

2017-05-29T06:22:48+00:00

With CONFIG_DEBUG_PREEMPT enabled, I get:

  BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
  caller is debug_smp_processor_id
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.12.0-rc2+ #2
  Call Trace:
   dump_stack
   check_preemption_disabled
   debug_smp_processor_id
   save_microcode_in_initrd_amd
   ? microcode_init
   save_microcode_in_initrd
   ...

because, well, it says it above, we're using smp_processor_id() in
preemptible code.

But passing the CPU number is not really needed. It is only used to
determine whether we're on the BSP, and, if so, to save the microcode
patch for early loading.

 [ We don't absolutely need to do it on the BSP but we do that
   customarily there. ]

Instead, convert that function parameter to a boolean which denotes
whether the patch should be saved or not, thereby avoiding the use of
smp_processor_id() in preemptible code.

Signed-off-by: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20170528200414.31305-1-bp@alien8.de
Signed-off-by: Ingo Molnar

x86/MCE: Export memory_error()

2017-05-21T19:39:58+00:00

Export the function which checks whether an MCE is a memory error to
other users so that we can reuse the logic. Drop the boot_cpu_data use,
while at it, as mce.cpuvendor already has the CPU vendor in there.

Integrate a piece from a patch from Vishal Verma
 to export it for modules (nfit).

The main reason we're exporting it is that the nfit handler
nfit_handle_mce() needs to detect a memory error properly before doing
its recovery actions.

Signed-off-by: Borislav Petkov 
Cc: Tony Luck 
Cc: Vishal Verma 
Cc: 
Link: http://lkml.kernel.org/r/20170519093915.15413-2-bp@alien8.de
Signed-off-by: Thomas Gleixner

Tigran has moved

2017-05-12T22:57:15+00:00

Cc: Tigran Aivazian 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-12T17:11:50+00:00

Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - two boot crash fixes
   - unwinder fixes
   - kexec related kernel direct mappings enhancements/fixes
   - more Clang support quirks
   - minor cleanups
   - Documentation fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel_rdt: Fix a typo in Documentation
  x86/build: Don't add -maccumulate-outgoing-args w/o compiler support
  x86/boot/32: Fix UP boot on Quark and possibly other platforms
  x86/mm/32: Set the '__vmalloc_start_set' flag in initmem_init()
  x86/kexec/64: Use gbpages for identity mappings if available
  x86/mm: Add support for gbpages to kernel_ident_mapping_init()
  x86/boot: Declare error() as noreturn
  x86/mm/kaslr: Use the _ASM_MUL macro for multiplication to work around Clang incompatibility
  x86/mm: Fix boot crash caused by incorrect loop count calculation in sync_global_pgds()
  x86/asm: Don't use RBP as a temporary register in csum_partial_copy_generic()
  x86/microcode/AMD: Remove redundant NULL check on mc

Merge tag 'for-linus-4.12b-rc0c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2017-05-12T17:09:14+00:00

Pull xen fixes from Juergen Gross:
 "This contains two fixes for booting under Xen introduced during this
  merge window and two fixes for older problems, where one is just much
  more probable due to another merge window change"

* tag 'for-linus-4.12b-rc0c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: adjust early dom0 p2m handling to xen hypervisor behavior
  x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen
  xen/x86: Do not call xen_init_time_ops() until shared_info is initialized
  x86/xen: fix xsave capability setting

x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen

2017-05-11T13:55:14+00:00

When running as Xen pv guest X86_BUG_SYSRET_SS_ATTRS must not be set
on AMD cpus.

This bug/feature bit is kind of special as it will be used very early
when switching threads. Setting the bit and clearing it a little bit
later leaves a critical window where things can go wrong. This time
window has enlarged a little bit by using setup_clear_cpu_cap() instead
of the hypervisor's set_cpu_features callback. It seems this larger
window now makes it rather easy to hit the problem.

The proper solution is to never set the bit in case of Xen.

Signed-off-by: Juergen Gross 
Reviewed-by: Boris Ostrovsky 
Acked-by: Thomas Gleixner 
Signed-off-by: Juergen Gross

x86: use set_memory.h header

2017-05-09T00:15:13+00:00

set_memory_* functions have moved to set_memory.h.  Switch to this
explicitly.

Link: http://lkml.kernel.org/r/1488920133-27229-6-git-send-email-labbott@redhat.com
Signed-off-by: Laura Abbott 
Acked-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds