| 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
| ||
|
Message-Id: <1364810209-25954-3-git-send-email-xiaoguangrong@linux.vnet.ibm.com>
Date: Mon, 1 Apr 2013 17:56:45 +0800
From: Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
To: mtosatti@...hat.com
Cc: gleb@...hat.com, linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
Subject: [PATCH v2 2/6] KVM: MMU: store generation-number into mmio spte
Store the generation-number into bit3 ~ bit11 and bit52 ~ bit61, totally
19 bits can be used, it should be enough for nearly all most common cases
In this patch, the generation-number is always 0, it will be changed in
the later patch
Signed-off-by: Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
---
arch/x86/kvm/mmu.c | 58 +++++++++++++++++++++++++++++++++++--------
arch/x86/kvm/mmutrace.h | 10 ++++---
arch/x86/kvm/paging_tmpl.h | 3 +-
3 files changed, 55 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 1ebca53..be4f733 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -197,15 +197,50 @@ void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask)
}
EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_mask);
-static void mark_mmio_spte(u64 *sptep, u64 gfn, unsigned access)
+/*
+ * spte bits of bit 3 ~ bit 11 are used as low 9 bits of generation number,
+ * the bits of bits 52 ~ bit 61 are used as high 10 bits of generation
+ * number.
+ */
+#define MMIO_SPTE_GEN_LOW_SHIFT 3
+#define MMIO_SPTE_GEN_HIGH_SHIFT 52
+
+#define MMIO_GEN_LOW_SHIFT 9
+#define MMIO_GEN_LOW_MASK ((1 << MMIO_GEN_LOW_SHIFT) - 1)
+#define MMIO_MAX_GEN ((1 << 19) - 1)
+
+static u64 generation_mmio_spte_mask(unsigned int gen)
{
- struct kvm_mmu_page *sp = page_header(__pa(sptep));
+ u64 mask;
+
+ WARN_ON(gen > MMIO_MAX_GEN);
+
+ mask = (gen & MMIO_GEN_LOW_MASK) << MMIO_SPTE_GEN_LOW_SHIFT;
+ mask |= ((u64)gen >> MMIO_GEN_LOW_SHIFT) << MMIO_SPTE_GEN_HIGH_SHIFT;
+ return mask;
+}
+
+static unsigned int get_mmio_spte_generation(u64 spte)
+{
+ unsigned int gen;
+
+ spte &= ~shadow_mmio_mask;
+
+ gen = (spte >> MMIO_SPTE_GEN_LOW_SHIFT) & MMIO_GEN_LOW_MASK;
+ gen |= (spte >> MMIO_SPTE_GEN_HIGH_SHIFT) << MMIO_GEN_LOW_SHIFT;
+ return gen;
+}
+
+static void mark_mmio_spte(struct kvm *kvm, u64 *sptep, u64 gfn,
+ unsigned access)
+{
+ u64 mask = generation_mmio_spte_mask(0);
access &= ACC_WRITE_MASK | ACC_USER_MASK;
+ mask |= shadow_mmio_mask | access | gfn << PAGE_SHIFT;
- sp->mmio_cached = true;
- trace_mark_mmio_spte(sptep, gfn, access);
- mmu_spte_set(sptep, shadow_mmio_mask | access | gfn << PAGE_SHIFT);
+ trace_mark_mmio_spte(sptep, gfn, access, 0);
+ mmu_spte_set(sptep, mask);
}
static bool is_mmio_spte(u64 spte)
@@ -223,10 +258,11 @@ static unsigned get_mmio_spte_access(u64 spte)
return (spte & ~shadow_mmio_mask) & ~PAGE_MASK;
}
-static bool set_mmio_spte(u64 *sptep, gfn_t gfn, pfn_t pfn, unsigned access)
+static bool set_mmio_spte(struct kvm *kvm, u64 *sptep, gfn_t gfn,
+ pfn_t pfn, unsigned access)
{
if (unlikely(is_noslot_pfn(pfn))) {
- mark_mmio_spte(sptep, gfn, access);
+ mark_mmio_spte(kvm, sptep, gfn, access);
return true;
}
@@ -2335,7 +2371,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
u64 spte;
int ret = 0;
- if (set_mmio_spte(sptep, gfn, pfn, pte_access))
+ if (set_mmio_spte(vcpu->kvm, sptep, gfn, pfn, pte_access))
return 0;
spte = PT_PRESENT_MASK;
@@ -3388,8 +3424,8 @@ static inline void protect_clean_gpte(unsigned *access, unsigned gpte)
*access &= mask;
}
-static bool sync_mmio_spte(u64 *sptep, gfn_t gfn, unsigned access,
- int *nr_present)
+static bool sync_mmio_spte(struct kvm *kvm, u64 *sptep, gfn_t gfn,
+ unsigned access, int *nr_present)
{
if (unlikely(is_mmio_spte(*sptep))) {
if (gfn != get_mmio_spte_gfn(*sptep)) {
@@ -3398,7 +3434,7 @@ static bool sync_mmio_spte(u64 *sptep, gfn_t gfn, unsigned access,
}
(*nr_present)++;
- mark_mmio_spte(sptep, gfn, access);
+ mark_mmio_spte(kvm, sptep, gfn, access);
return true;
}
diff --git a/arch/x86/kvm/mmutrace.h b/arch/x86/kvm/mmutrace.h
index b8f6172..f5b62a7 100644
--- a/arch/x86/kvm/mmutrace.h
+++ b/arch/x86/kvm/mmutrace.h
@@ -197,23 +197,25 @@ DEFINE_EVENT(kvm_mmu_page_class, kvm_mmu_prepare_zap_page,
TRACE_EVENT(
mark_mmio_spte,
- TP_PROTO(u64 *sptep, gfn_t gfn, unsigned access),
- TP_ARGS(sptep, gfn, access),
+ TP_PROTO(u64 *sptep, gfn_t gfn, unsigned access, unsigned int gen),
+ TP_ARGS(sptep, gfn, access, gen),
TP_STRUCT__entry(
__field(void *, sptep)
__field(gfn_t, gfn)
__field(unsigned, access)
+ __field(unsigned int, gen)
),
TP_fast_assign(
__entry->sptep = sptep;
__entry->gfn = gfn;
__entry->access = access;
+ __entry->gen = gen;
),
- TP_printk("sptep:%p gfn %llx access %x", __entry->sptep, __entry->gfn,
- __entry->access)
+ TP_printk("sptep:%p gfn %llx access %x gen %x", __entry->sptep,
+ __entry->gfn, __entry->access, __entry->gen)
);
TRACE_EVENT(
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index af143f0..bddc5f6 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -791,7 +791,8 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
pte_access &= gpte_access(vcpu, gpte);
protect_clean_gpte(&pte_access, gpte);
- if (sync_mmio_spte(&sp->spt[i], gfn, pte_access, &nr_present))
+ if (sync_mmio_spte(vcpu->kvm, &sp->spt[i], gfn, pte_access,
+ &nr_present))
continue;
if (gfn != sp->gfns[i]) {
--
1.7.7.6
--
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/
Powered by blists - more mailing lists