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Subject[PATCH] KVM: x86/mmu: Fix a benign Bitwise vs. Logical OR mixup
Date
Use a Logical OR in __is_rsvd_bits_set() to combine the two reserved bit
checks, which are obviously intended to be logical statements. Switching
to a Logical OR is functionally a nop, but allows the compiler to better
optimize the checks.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/mmu/mmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 7269130ea5e2..72e845709027 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3970,7 +3970,7 @@ __is_rsvd_bits_set(struct rsvd_bits_validate *rsvd_check, u64 pte, int level)
{
int bit7 = (pte >> 7) & 1, low6 = pte & 0x3f;

- return (pte & rsvd_check->rsvd_bits_mask[bit7][level-1]) |
+ return (pte & rsvd_check->rsvd_bits_mask[bit7][level-1]) ||
((rsvd_check->bad_mt_xwr & (1ull << low6)) != 0);
}

--
2.24.1
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