diff mbox series

[PULL,4/9] target/i386: Adjust feature level according to FEAT_7_1_EDX

Message ID 20230707140432.88073-5-pbonzini@redhat.com
State New
Headers show
Series [PULL,1/9] python: bump minimum requirements so they are compatible with 3.12 | expand

Commit Message

Paolo Bonzini July 7, 2023, 2:04 p.m. UTC 
From: Tao Su <tao1.su@linux.intel.com>

If FEAT_7_1_EAX is 0 and FEAT_7_1_EDX is non-zero, as is the case
with a Granite Rapids host and
'-cpu host,-avx-vnni,-avx512-bf16,-fzrm,-fsrs,-fsrc,-amx-fp16', we can't
get CPUID_7_1 leaf even though CPUID_7_1_EDX has non-zero value.

Update cpuid_level_func7 according to CPUID_7_1_EDX, otherwise
guest may report wrong maximum number sub-leaves in leaf 07H.

Fixes: eaaa197d5b11 ("target/i386: Add support for AVX-VNNI-INT8 in CPUID enumeration")
Cc: qemu-stable@nongnu.org
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-ID: <20230706054949.66556-2-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/cpu.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Michael Tokarev July 17, 2023, 11:19 a.m. UTC | #1 
07.07.2023 17:04, Paolo Bonzini wrote:
> From: Tao Su <tao1.su@linux.intel.com>
> 
> If FEAT_7_1_EAX is 0 and FEAT_7_1_EDX is non-zero, as is the case
> with a Granite Rapids host and
> '-cpu host,-avx-vnni,-avx512-bf16,-fzrm,-fsrs,-fsrc,-amx-fp16', we can't
> get CPUID_7_1 leaf even though CPUID_7_1_EDX has non-zero value.
> 
> Update cpuid_level_func7 according to CPUID_7_1_EDX, otherwise
> guest may report wrong maximum number sub-leaves in leaf 07H.
> 
> Fixes: eaaa197d5b11 ("target/i386: Add support for AVX-VNNI-INT8 in CPUID enumeration")
> Cc: qemu-stable@nongnu.org

This patch is not applicable for any stable qemu releases, since the
commit it fixes (eaaa197d5b11, which also introduced FEAT_7_1_EDX) is
not in any released version, it is v8.0.0-290-geaaa197d5b.

This is just for the information (I'm not picking it up for stable),
there's nothing wrong with it tagged for stable initially.

Thanks!

/mjt
diff mbox series

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index b5688cabb4f..952744af97c 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6880,6 +6880,7 @@  void x86_cpu_expand_features(X86CPU *cpu, Error **errp)
         x86_cpu_adjust_feat_level(cpu, FEAT_6_EAX);
         x86_cpu_adjust_feat_level(cpu, FEAT_7_0_ECX);
         x86_cpu_adjust_feat_level(cpu, FEAT_7_1_EAX);
+        x86_cpu_adjust_feat_level(cpu, FEAT_7_1_EDX);
         x86_cpu_adjust_feat_level(cpu, FEAT_8000_0001_EDX);
         x86_cpu_adjust_feat_level(cpu, FEAT_8000_0001_ECX);
         x86_cpu_adjust_feat_level(cpu, FEAT_8000_0007_EDX);