diff options
| author | Linus Torvalds | 2005-09-17 15:41:04 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2005-09-17 15:41:04 -0700 |
| commit | bc5e8fdfc622b03acf5ac974a1b8b26da6511c99 (patch) | |
| tree | 912dbeaadd246bd053a9650c79d1bd98bbc71556 | |
| parent | 61ffcafafb3d985e1ab8463be0187b421614775c (diff) | |
x86-64/smp: fix random SIGSEGV issues
They seem to have been due to AMD errata 63/122; the fix is to disable
TLB flush filtering in SMP configurations.
Confirmed to fix the problem by Andrew Walrond <andrew@walrond.org>
[ Let's see if we'll have a better fix eventually, this is the Q&D
"let's get this fixed and out there" version ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | arch/x86_64/kernel/setup.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c index 351d8d64c2fb..238f73e1a834 100644 --- a/arch/x86_64/kernel/setup.c +++ b/arch/x86_64/kernel/setup.c @@ -831,11 +831,26 @@ static void __init amd_detect_cmp(struct cpuinfo_x86 *c) #endif } +#define HWCR 0xc0010015 + static int __init init_amd(struct cpuinfo_x86 *c) { int r; int level; +#ifdef CONFIG_SMP + unsigned long value; + + // Disable TLB flush filter by setting HWCR.FFDIS: + // bit 6 of msr C001_0015 + // + // Errata 63 for SH-B3 steppings + // Errata 122 for all(?) steppings + rdmsrl(HWCR, value); + value |= 1 << 6; + wrmsrl(HWCR, value); +#endif + /* Bit 31 in normal CPUID used for nonstandard 3DNow ID; 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway */ clear_bit(0*32+31, &c->x86_capability); |