iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/topology: Set cpu_die_id only if DIE_TYPE found

Browse Source 
[ 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@alien8.de>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201109210659.754018-5-Yazen.Ghannam@amd.com
Stable-dep-of: 2b12a7a126d6 ("x86/topology: Fix multiple packages shown on a single-package system")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Yazen Ghannam 2020-11-09 21:06:59 +00:00 committed by Greg Kroah-Hartman
parent 570fa3bcd2
commit f5ad52da14
1 changed files with 8 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/kernel/cpu/topology.c
View File

@ -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);
/*