summaryrefslogtreecommitdiff
path: root/arch/x86
diff options
context:
space:
mode:
authorBorislav Petkov <bp@suse.de>2017-01-05 10:26:38 +0100
committerIngo Molnar <mingo@kernel.org>2017-01-06 08:37:41 +0100
commita33d331761bc5dd330499ca5ceceb67f0640a8e6 (patch)
tree3c8d1d08f992cfcc2f87f77309aa586c22663296 /arch/x86
parent159d3726db12b3476bc59ea0ab0a702103d466b5 (diff)
x86/CPU/AMD: Fix Bulldozer topology
The following commit: 8196dab4fc15 ("x86/cpu: Get rid of compute_unit_id") ... broke the initial strategy for Bulldozer-based cores' topology, where we consider each thread of a compute unit a standalone core and not a HT or SMT thread. Revert to the firmware-supplied core_id numbering and do not make them thread siblings as we don't consider them for such even if they technically are, more or less. Reported-and-tested-by: Brice Goglin <Brice.Goglin@inria.fr> Tested-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> # v4.6+ Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 8196dab4fc15 ("x86/cpu: Get rid of compute_unit_id") Link: http://lkml.kernel.org/r/20170105092638.5247-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/kernel/cpu/amd.c9
1 files changed, 1 insertions, 8 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 71cae73a5076..1d3167269a67 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -309,15 +309,8 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
/* get information required for multi-node processors */
if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
- u32 eax, ebx, ecx, edx;
- cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
- node_id = ecx & 7;
-
- /* get compute unit information */
- smp_num_siblings = ((ebx >> 8) & 3) + 1;
- c->x86_max_cores /= smp_num_siblings;
- c->cpu_core_id = ebx & 0xff;
+ node_id = cpuid_ecx(0x8000001e) & 7;
/*
* We may have multiple LLCs if L3 caches exist, so check if we