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yaml --- r: 282000 b: refs/heads/master c: 5d9ca30 h: refs/heads/master v: v3
git-mirror · Dec 27, 2011 · d1fba50 · d1fba50
1 parent ef56835
commit d1fba50
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Showing 2 changed files with 9 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 889e5cbced6c191bb7e25c1b30b43e59a12561f9
+refs/heads/master: 5d9ca30e96f567b67a36727aa4ebb34911a2b84a
diff --git a/trunk/arch/x86/kvm/mmu.c b/trunk/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;