linux-kernel - [PATCH 12/12] KVM: MMU: clean up spte_write

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 30 Jul 2013 21:02:10 +0800
From:	Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
To:	gleb@...hat.com
Cc:	avi.kivity@...il.com, mtosatti@...hat.com, pbonzini@...hat.com,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
	Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
Subject: [PATCH 12/12] KVM: MMU: clean up spte_write_protect

Now, the only user of spte_write_protect is rmap_write_protect which
always calls spte_write_protect with pt_protect = true, so drop
it and the unused parameter @kvm

Signed-off-by: Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
---
 arch/x86/kvm/mmu.c | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a50eea8..8073c1f 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1319,8 +1319,7 @@ static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
 }
 
 /*
- * Write-protect on the specified @sptep, @pt_protect indicates whether
- * spte write-protection is caused by protecting shadow page table.
+ * Write-protect on the specified @sptep.
  *
  * Note: write protection is difference between drity logging and spte
  * protection:
@@ -1331,25 +1330,23 @@ static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep)
  *
  * Return true if tlb need be flushed.
  */
-static bool spte_write_protect(struct kvm *kvm, u64 *sptep, bool pt_protect)
+static bool spte_write_protect(u64 *sptep)
 {
 	u64 spte = *sptep;
 
 	if (!is_writable_pte(spte) &&
-	      !(pt_protect && spte_is_locklessly_modifiable(spte)))
+	      !spte_is_locklessly_modifiable(spte))
 		return false;
 
 	rmap_printk("rmap_write_protect: spte %p %llx\n", sptep, *sptep);
 
-	if (pt_protect)
-		spte &= ~SPTE_MMU_WRITEABLE;
-	spte = spte & ~PT_WRITABLE_MASK;
+	spte &= ~SPTE_MMU_WRITEABLE;
+	spte &= ~PT_WRITABLE_MASK;
 
 	return mmu_spte_update(sptep, spte);
 }
 
-static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp,
-				 bool pt_protect)
+static bool __rmap_write_protect(unsigned long *rmapp)
 {
 	u64 *sptep;
 	struct rmap_iterator iter;
@@ -1358,7 +1355,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp,
 	for (sptep = rmap_get_first(*rmapp, &iter); sptep;) {
 		BUG_ON(!(*sptep & PT_PRESENT_MASK));
 
-		flush |= spte_write_protect(kvm, sptep, pt_protect);
+		flush |= spte_write_protect(sptep);
 		sptep = rmap_get_next(&iter);
 	}
 
@@ -1426,7 +1423,7 @@ static bool rmap_write_protect(struct kvm *kvm, u64 gfn)
 	for (i = PT_PAGE_TABLE_LEVEL;
 	     i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) {
 		rmapp = __gfn_to_rmap(gfn, i, slot);
-		write_protected |= __rmap_write_protect(kvm, rmapp, true);
+		write_protected |= __rmap_write_protect(rmapp);
 	}
 
 	return write_protected;
-- 
1.8.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/