| commit | 184e1fdfea066ab8f12a1e8912f402d2d6556d11 | |
| author | Huang Ying <ying.huang@intel.com> | |
| Mon, 15 Jun 2009 07:37:07 +0000 (15 15:37 +0800) | ||
| committer | H. Peter Anvin <hpa@zytor.com> | |
| Tue, 16 Jun 2009 23:56:04 +0000 (16 16:56 -0700) | ||
| tree | f9ffff79d1924f530e582a2aab9f0cb032f0a4e3 | treesnapshot (tar.gz zip) |
| parent | 300df7dc89cc276377fc020704e34875d5c473b6 | commitdiff |
x86, mce: fix a race condition about mce_callin and no_way_out
If one CPU has no_way_out == 1, all other CPUs should have no_way_out
== 1. But despite global_nwo is read after mce_callin, global_nwo is
updated after mce_callin too. So it is possible that some CPU read
global_nwo before some other CPU update global_nwo, so that no_way_out
== 1 for some CPU, while no_way_out == 0 for some other CPU.
This patch fixes this race condition via moving mce_callin updating
after global_nwo updating, with a smp_wmb in between. A smp_rmb is
added between their reading too.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
If one CPU has no_way_out == 1, all other CPUs should have no_way_out
== 1. But despite global_nwo is read after mce_callin, global_nwo is
updated after mce_callin too. So it is possible that some CPU read
global_nwo before some other CPU update global_nwo, so that no_way_out
== 1 for some CPU, while no_way_out == 0 for some other CPU.
This patch fixes this race condition via moving mce_callin updating
after global_nwo updating, with a smp_wmb in between. A smp_rmb is
added between their reading too.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
| arch/x86/kernel/cpu/mcheck/mce.c | diffblobblamehistory |