1. 02 9月, 2013 3 次提交
  2. 26 8月, 2013 1 次提交
  3. 23 8月, 2013 2 次提交
  4. 20 8月, 2013 1 次提交
    • Y
      x86/ioapic/kcrash: Prevent crash_kexec() from deadlocking on ioapic_lock · 17405453
      Yoshihiro YUNOMAE 提交于
      Prevent crash_kexec() from deadlocking on ioapic_lock. When
      crash_kexec() is executed on a CPU, the CPU will take ioapic_lock
      in disable_IO_APIC(). So if the cpu gets an NMI while locking
      ioapic_lock, a deadlock will happen.
      
      In this patch, ioapic_lock is zapped/initialized before disable_IO_APIC().
      
      You can reproduce this deadlock the following way:
      
      1. Add mdelay(1000) after raw_spin_lock_irqsave() in
         native_ioapic_set_affinity()@arch/x86/kernel/apic/io_apic.c
      
         Although the deadlock can occur without this modification, it will increase
         the potential of the deadlock problem.
      
      2. Build and install the kernel
      
      3. Set up the OS which will run panic() and kexec when NMI is injected
          # echo "kernel.unknown_nmi_panic=1" >> /etc/sysctl.conf
          # vim /etc/default/grub
            add "nmi_watchdog=0 crashkernel=256M" in GRUB_CMDLINE_LINUX line
          # grub2-mkconfig
      
      4. Reboot the OS
      
      5. Run following command for each vcpu on the guest
          # while true; do echo <CPU num> > /proc/irq/<IO-APIC-edge or IO-APIC-fasteoi>/smp_affinitity; done;
         By running this command, cpus will get ioapic_lock for setting affinity.
      
      6. Inject NMI (push a dump button or execute 'virsh inject-nmi <domain>' if you
         use VM). After injecting NMI, panic() is called in an nmi-handler context.
         Then, kexec will normally run in panic(), but the operation will be stopped
         by deadlock on ioapic_lock in crash_kexec()->machine_crash_shutdown()->
         native_machine_crash_shutdown()->disable_IO_APIC()->clear_IO_APIC()->
         clear_IO_APIC_pin()->ioapic_read_entry().
      Signed-off-by: NYoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Gleb Natapov <gleb@redhat.com>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Joerg Roedel <joro@8bytes.org>
      Cc: Marcelo Tosatti <mtosatti@redhat.com>
      Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
      Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
      Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
      Cc: Eric W. Biederman <ebiederm@xmission.com>
      Cc: yrl.pp-manager.tt@hitachi.com
      Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: Seiji Aguchi <seiji.aguchi@hds.com>
      Link: http://lkml.kernel.org/r/20130820070107.28245.83806.stgit@yunodevelSigned-off-by: NIngo Molnar <mingo@kernel.org>
      17405453
  5. 16 8月, 2013 3 次提交
  6. 14 8月, 2013 1 次提交
  7. 13 8月, 2013 2 次提交
    • T
      x86, microcode, AMD: Fix early microcode loading · 84516098
      Torsten Kaiser 提交于
      load_microcode_amd() (and the helper it is using) should not have an
      cpu parameter. The microcode loading does not depend on the CPU wrt the
      patches loaded since they will end up in a global list for all CPUs
      anyway.
      
      The change from cpu to x86family in load_microcode_amd()
      now allows to drop the code messing with cpu_data(cpu) from
      collect_cpu_info_amd_early(), which is wrong anyway because at that
      point the per-cpu cpu_info is not yet setup (These values would later be
      overwritten by smp_store_boot_cpu_info() / smp_store_cpu_info()).
      
      Fold the rest of collect_cpu_info_amd_early() into load_ucode_amd_ap(),
      because its only used at one place and without the cpuinfo_x86 accesses
      it was not much left.
      Signed-off-by: NTorsten Kaiser <just.for.lkml@googlemail.com>
      [ Fengguang: build fix ]
      Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
      [ Boris: adapt it to current tree. ]
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      84516098
    • T
      x86, microcode, AMD: Make cpu_has_amd_erratum() use the correct struct cpuinfo_x86 · 8c6b79bb
      Torsten Kaiser 提交于
      cpu_has_amd_erratum() is buggy, because it uses the per-cpu cpu_info
      before it is filled by smp_store_boot_cpu_info() / smp_store_cpu_info().
      
      If early microcode loading is enabled its collect_cpu_info_amd_early()
      will fill ->x86 and so the fallback to boot_cpu_data is not used. But
      ->x86_vendor was not filled and is still X86_VENDOR_INTEL resulting in
      no errata fixes getting applied and my system hangs on boot.
      
      Using cpu_info in cpu_has_amd_erratum() is wrong anyway: its only
      caller init_amd() will have a struct cpuinfo_x86 as parameter and the
      set_cpu_bug() that is controlled by cpu_has_amd_erratum() also only uses
      that struct.
      
      So pass the struct cpuinfo_x86 from init_amd() to cpu_has_amd_erratum()
      and the broken fallback can be dropped.
      
      [ Boris: Drop WARN_ON() since we're called only from init_amd() ]
      Signed-off-by: NTorsten Kaiser <just.for.lkml@googlemail.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      8c6b79bb
  8. 12 8月, 2013 1 次提交
  9. 07 8月, 2013 10 次提交
  10. 05 8月, 2013 1 次提交
    • V
      perf/x86: Fix intel QPI uncore event definitions · c9601247
      Vince Weaver 提交于
      John McCalpin reports that the "drs_data" and "ncb_data" QPI
      uncore events are missing the "extra bit" and always return zero
      values unless the bit is properly set.
      
      More details from him:
      
       According to the Xeon E5-2600 Product Family Uncore Performance
       Monitoring Guide, Table 2-94, about 1/2 of the QPI Link Layer events
       (including the ones that "perf" calls "drs_data" and "ncb_data") require
       that the "extra bit" be set.
      
       This was confusing for a while -- a note at the bottom of page 94 says
       that the "extra bit" is bit 16 of the control register.
       Unfortunately, Table 2-86 clearly says that bit 16 is reserved and must
       be zero.  Looking around a bit, I found that bit 21 appears to be the
       correct "extra bit", and further investigation shows that "perf" actually
       agrees with me:
      	[root@c560-003.stampede]# cat /sys/bus/event_source/devices/uncore_qpi_0/format/event
      	config:0-7,21
      
       So the command
      	# perf -e "uncore_qpi_0/event=drs_data/"
       Is the same as
      	# perf -e "uncore_qpi_0/event=0x02,umask=0x08/"
       While it should be
      	# perf -e "uncore_qpi_0/event=0x102,umask=0x08/"
      
       I confirmed that this last version gives results that agree with the
       amount of data that I expected the STREAM benchmark to move across the QPI
       link in the second (cross-chip) test of the original script.
      Reported-by: NJohn McCalpin <mccalpin@tacc.utexas.edu>
      Signed-off-by: NVince Weaver <vincent.weaver@maine.edu>
      Cc: zheng.z.yan@intel.com
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: <stable@kernel.org>
      Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1308021037280.26119@vincent-weaver-1.um.maine.eduSigned-off-by: NIngo Molnar <mingo@kernel.org>
      c9601247
  11. 31 7月, 2013 2 次提交
  12. 30 7月, 2013 1 次提交
  13. 27 7月, 2013 1 次提交
    • H
      x86, fpu: correct the asm constraints for fxsave, unbreak mxcsr.daz · eaa5a990
      H.J. Lu 提交于
      GCC will optimize mxcsr_feature_mask_init in arch/x86/kernel/i387.c:
      
      		memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct));
      		asm volatile("fxsave %0" : : "m" (fx_scratch));
      		mask = fx_scratch.mxcsr_mask;
      		if (mask == 0)
      			mask = 0x0000ffbf;
      
      to
      
      		memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct));
      		asm volatile("fxsave %0" : : "m" (fx_scratch));
      		mask = 0x0000ffbf;
      
      since asm statement doesn’t say it will update fx_scratch.  As the
      result, the DAZ bit will be cleared.  This patch fixes it. This bug
      dates back to at least kernel 2.6.12.
      Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      Cc: <stable@vger.kernel.org>
      eaa5a990
  14. 23 7月, 2013 4 次提交
  15. 19 7月, 2013 3 次提交
  16. 17 7月, 2013 3 次提交
  17. 16 7月, 2013 1 次提交