diff options
| author |  Jing Liu <jing2.liu@intel.com>
| 2022-01-05 04:35:14 -0800 |
|---|---|---|
| committer |  Paolo Bonzini <pbonzini@redhat.com>
| 2022-01-07 13:33:04 -0500 |
| commit | cc04b6a21d431359eceeec0d812b492088b04af5 (patch) | |
| tree | 39bd997cf64cc983f1efe5553ebd833a8befb501 /arch/x86/kvm/cpuid.c | |
| parent | x86/fpu: Prepare guest FPU for dynamically enabled FPU features (diff) | |
| download | linux-cc04b6a21d431359eceeec0d812b492088b04af5.tar.gz linux-cc04b6a21d431359eceeec0d812b492088b04af5.tar.bz2 linux-cc04b6a21d431359eceeec0d812b492088b04af5.zip | |
kvm: x86: Fix xstate_required_size() to follow XSTATE alignment rule
CPUID.0xD.1.EBX enumerates the size of the XSAVE area (in compacted
format) required by XSAVES. If CPUID.0xD.i.ECX[1] is set for a state
component (i), this state component should be located on the next
64-bytes boundary following the preceding state component in the
compacted layout.
Fix xstate_required_size() to follow the alignment rule. AMX is the
first state component with 64-bytes alignment to catch this bug.
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-4-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 0b920e12bb6d..f3e6fda6b858 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -42,7 +42,11 @@ static u32 xstate_required_size(u64 xstate_bv, bool compacted) if (xstate_bv & 0x1) { u32 eax, ebx, ecx, edx, offset; cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx); - offset = compacted ? ret : ebx; + /* ECX[1]: 64B alignment in compacted form */ + if (compacted) + offset = (ecx & 0x2) ? ALIGN(ret, 64) : ret; + else + offset = ebx; ret = max(ret, offset + eax); } |