1. 19 8月, 2009 26 次提交
  2. 18 8月, 2009 12 次提交
  3. 17 8月, 2009 2 次提交
    • I
      x86, mce: Don't initialize MCEs on unknown CPUs · e412cd25
      Ingo Molnar 提交于
      An older test-box started hanging at the following point during
      bootup:
      
       [    0.022996] Mount-cache hash table entries: 512
       [    0.024996] Initializing cgroup subsys debug
       [    0.025996] Initializing cgroup subsys cpuacct
       [    0.026995] Initializing cgroup subsys devices
       [    0.027995] Initializing cgroup subsys freezer
       [    0.028995] mce: CPU supports 5 MCE banks
      
      I've bisected it down to commit 4efc0670 ("x86, mce: use 64bit
      machine check code on 32bit"), which utilizes the MCE code on
      32-bit systems too.
      
      The problem is caused by this detail in my config:
      
        # CONFIG_CPU_SUP_INTEL is not set
      
      This disables the quirks in mce_cpu_quirks() but still enables
      MCE support - which then hangs due to the missing quirk
      workaround needed on this CPU:
      
      	if (c->x86 == 6 && c->x86_model < 0x1A && banks > 0)
      		mce_banks[0].init = 0;
      
      The safe solution is to not initialize MCEs if we dont know on
      what CPU we are running (or if that CPU's support code got
      disabled in the config).
      
      Also be a bit more defensive on 32-bit systems: dont do a
      boot-time dump of pending MCEs not just on the specific system
      that we found a problem with (Pentium-M), but earlier ones as
      well.
      
      Now this problem is probably not common and disabling CPU
      support is rare - but still being more defensive in something
      we turned on for a wide range of CPUs is prudent.
      
      Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      LKML-Reference: Message-ID: <4A88E3E4.40506@jp.fujitsu.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      e412cd25
    • B
      x86, mce: don't log boot MCEs on Pentium M (model == 13) CPUs · c7f6fa44
      Bartlomiej Zolnierkiewicz 提交于
      On my legacy Pentium M laptop (Acer Extensa 2900) I get bogus MCE on a cold
      boot with CONFIG_X86_NEW_MCE enabled, i.e. (after decoding it with mcelog):
      
      MCE 0
      HARDWARE ERROR. This is *NOT* a software problem!
      Please contact your hardware vendor
      CPU 0 BANK 1 MCG status:
      MCi status:
      Error overflow
      Uncorrected error
      Error enabled
      Processor context corrupt
      MCA: Data CACHE Level-1 UNKNOWN Error
      STATUS f200000000000195 MCGSTATUS 0
      
      [ The other STATUS values observed: f2000000000001b5 (... UNKNOWN error)
        and f200000000000115 (... READ Error).
      
        To verify that this is not a CONFIG_X86_NEW_MCE bug I also modified
        the CONFIG_X86_OLD_MCE code (which doesn't log any MCEs) to dump
        content of STATUS MSR before it is cleared during initialization. ]
      
      Since the bogus MCE results in a kernel taint (which in turn disables
      lockdep support) don't log boot MCEs on Pentium M (model == 13) CPUs
      by default ("mce=bootlog" boot parameter can be be used to get the old
      behavior).
      Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      Reviewed-by: NAndi Kleen <andi@firstfloor.org>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      c7f6fa44