From: Yazen Ghannam <yazen.ghannam@xxxxxxx> [ Upstream commit cb09a379724d299c603a7a79f444f52a9a75b8d2 ] CPUID Leaf 0x1F defines a DIE_TYPE level (nb: ECX[8:15] level type == 0x5), but CPUID Leaf 0xB does not. However, detect_extended_topology() will set struct cpuinfo_x86.cpu_die_id regardless of whether a valid Die ID was found. Only set cpu_die_id if a DIE_TYPE level is found. CPU topology code may use another value for cpu_die_id, e.g. the AMD NodeId on AMD-based systems. Code ordering should be maintained so that the CPUID Leaf 0x1F Die ID value will take precedence on systems that may use another value. Suggested-by: Borislav Petkov <bp@xxxxxxxxx> Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Link: https://lkml.kernel.org/r/20201109210659.754018-5-Yazen.Ghannam@xxxxxxx Stable-dep-of: 2b12a7a126d6 ("x86/topology: Fix multiple packages shown on a single-package system") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/kernel/cpu/topology.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c index 91288da29599..8678864ce712 100644 --- a/arch/x86/kernel/cpu/topology.c +++ b/arch/x86/kernel/cpu/topology.c @@ -96,6 +96,7 @@ int detect_extended_topology(struct cpuinfo_x86 *c) unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width; unsigned int core_select_mask, core_level_siblings; unsigned int die_select_mask, die_level_siblings; + bool die_level_present = false; int leaf; leaf = detect_extended_topology_leaf(c); @@ -126,6 +127,7 @@ int detect_extended_topology(struct cpuinfo_x86 *c) die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); } if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) { + die_level_present = true; die_level_siblings = LEVEL_MAX_SIBLINGS(ebx); die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); } @@ -139,8 +141,12 @@ int detect_extended_topology(struct cpuinfo_x86 *c) c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width) & core_select_mask; - c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid, - core_plus_mask_width) & die_select_mask; + + if (die_level_present) { + c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid, + core_plus_mask_width) & die_select_mask; + } + c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, die_plus_mask_width); /* -- 2.35.1
