diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/mmu.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 986aea55366b..ca6f72ab4c3b 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3602,6 +3602,14 @@ static bool detect_write_misaligned(struct kvm_mmu_page *sp, gpa_t gpa, offset = offset_in_page(gpa); pte_size = sp->role.cr4_pae ? 8 : 4; + + /* + * Sometimes, the OS only writes the last one bytes to update status + * bits, for example, in linux, andb instruction is used in clear_bit(). + */ + if (!(offset & (pte_size - 1)) && bytes == 1) + return false; + misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1); misaligned |= bytes < 4; |