diff options
| author | Sean Christopherson <seanjc@google.com> | 2024-12-10 17:32:59 -0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2025-02-12 10:16:30 -0800 |
| commit | aa93b6f96f6486fa1a78b7b92ebe43f49f35d8bf (patch) | |
| tree | b710255189123cdeed266ad90b5c1c562bdb4eed | |
| parent | a11128ce16366d455a6f937e2a2d1aa2a8b2bd45 (diff) | |
KVM: x86: Use for-loop to iterate over XSTATE size entries
Rework xstate_required_size() to use a for-loop and continue, to make it
more obvious that the xstate_sizes[] lookups are indeed correctly bounded,
and to make it (hopefully) easier to understand that the loop is iterating
over supported XSAVE features.
Link: https://lore.kernel.org/r/20241211013302.1347853-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 29 |
1 files changed, 14 insertions, 15 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 269ffbd5c2e0..a57fa0123c77 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -58,25 +58,24 @@ void __init kvm_init_xstate_sizes(void) u32 xstate_required_size(u64 xstate_bv, bool compacted) { - int feature_bit = 0; u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; + int i; xstate_bv &= XFEATURE_MASK_EXTEND; - while (xstate_bv) { - if (xstate_bv & 0x1) { - struct cpuid_xstate_sizes *xs = &xstate_sizes[feature_bit]; - u32 offset; - - /* ECX[1]: 64B alignment in compacted form */ - if (compacted) - offset = (xs->ecx & 0x2) ? ALIGN(ret, 64) : ret; - else - offset = xs->ebx; - ret = max(ret, offset + xs->eax); - } + for (i = XFEATURE_YMM; i < ARRAY_SIZE(xstate_sizes) && xstate_bv; i++) { + struct cpuid_xstate_sizes *xs = &xstate_sizes[i]; + u32 offset; - xstate_bv >>= 1; - feature_bit++; + if (!(xstate_bv & BIT_ULL(i))) + continue; + + /* ECX[1]: 64B alignment in compacted form */ + if (compacted) + offset = (xs->ecx & 0x2) ? ALIGN(ret, 64) : ret; + else + offset = xs->ebx; + ret = max(ret, offset + xs->eax); + xstate_bv &= ~BIT_ULL(i); } return ret; |