Signed-off-by: Blaise Boscaccy <blaise.bosca...@oracle.com>
Signed-off-by: Vegard Nossum <vegard.nos...@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com>
---
xen/arch/arm/livepatch.c | 7 ++++---
xen/arch/x86/livepatch.c | 10 ++++++++++
xen/arch/x86/x86_64/mm.c | 33 ++++++++++++++++++++++++---------
xen/include/asm-x86/mm.h | 1 +
xen/include/xen/livepatch.h | 3 +++
5 files changed, 42 insertions(+), 12 deletions(-)
diff --git a/xen/arch/arm/livepatch.c b/xen/arch/arm/livepatch.c
index e1d5d58f97..1771b3c558 100644
--- a/xen/arch/arm/livepatch.c
+++ b/xen/arch/arm/livepatch.c
@@ -13,9 +13,10 @@
#include <asm/livepatch.h>
#include <asm/mm.h>
-/* Override macros from asm/page.h to make them work with mfn_t */
-#undef virt_to_mfn
-#define virt_to_mfn(va) _mfn(__virt_to_mfn(va))
+mfn_t arch_livepatch_lookup_mfn(unsigned long addr)
+{
+ return _mfn(__virt_to_mfn(addr));
+}
void arch_livepatch_revive(void)
{
diff --git a/xen/arch/x86/livepatch.c b/xen/arch/x86/livepatch.c
index 12287d445f..667573c6de 100644
--- a/xen/arch/x86/livepatch.c
+++ b/xen/arch/x86/livepatch.c
@@ -14,6 +14,16 @@
#include <asm/nmi.h>
#include <asm/livepatch.h>
+mfn_t arch_livepatch_lookup_mfn(unsigned long addr)
+{
+ unsigned long cr3 = read_cr3() >> PAGE_SHIFT;
+
+ if ( !mfn_valid(_mfn(cr3)) )
+ return INVALID_MFN;
+
+ return _do_page_walk(cr3, addr);
+}
+
void arch_livepatch_revive(void)
{
/* Nothing to do. */
diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c
index 11746730b4..f8a963bbba 100644
--- a/xen/arch/x86/x86_64/mm.c
+++ b/xen/arch/x86/x86_64/mm.c
@@ -44,29 +44,28 @@ unsigned int __read_mostly m2p_compat_vstart =
__HYPERVISOR_COMPAT_VIRT_START;
l2_pgentry_t *compat_idle_pg_table_l2;
-void *do_page_walk(struct vcpu *v, unsigned long addr)
+mfn_t _do_page_walk(unsigned long mfn, unsigned long addr)
{
- unsigned long mfn = pagetable_get_pfn(v->arch.guest_table);
l4_pgentry_t l4e, *l4t;
l3_pgentry_t l3e, *l3t;
l2_pgentry_t l2e, *l2t;
l1_pgentry_t l1e, *l1t;
- if ( !is_pv_vcpu(v) || !is_canonical_address(addr) )
- return NULL;
+ if ( !is_canonical_address(addr) )
+ return INVALID_MFN;
l4t = map_domain_page(_mfn(mfn));
l4e = l4t[l4_table_offset(addr)];
unmap_domain_page(l4t);
if ( !(l4e_get_flags(l4e) & _PAGE_PRESENT) )
- return NULL;
+ return INVALID_MFN;
l3t = map_l3t_from_l4e(l4e);
l3e = l3t[l3_table_offset(addr)];
unmap_domain_page(l3t);
mfn = l3e_get_pfn(l3e);
if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) || !mfn_valid(_mfn(mfn)) )
- return NULL;
+ return INVALID_MFN;
if ( (l3e_get_flags(l3e) & _PAGE_PSE) )
{
mfn += PFN_DOWN(addr & ((1UL << L3_PAGETABLE_SHIFT) - 1));
@@ -78,7 +77,7 @@ void *do_page_walk(struct vcpu *v, unsigned long addr)
unmap_domain_page(l2t);
mfn = l2e_get_pfn(l2e);
if ( !(l2e_get_flags(l2e) & _PAGE_PRESENT) || !mfn_valid(_mfn(mfn)) )
- return NULL;
+ return INVALID_MFN;
if ( (l2e_get_flags(l2e) & _PAGE_PSE) )
{
mfn += PFN_DOWN(addr & ((1UL << L2_PAGETABLE_SHIFT) - 1));
@@ -90,10 +89,26 @@ void *do_page_walk(struct vcpu *v, unsigned long addr)
unmap_domain_page(l1t);
mfn = l1e_get_pfn(l1e);
if ( !(l1e_get_flags(l1e) & _PAGE_PRESENT) || !mfn_valid(_mfn(mfn)) )
- return NULL;
+ return INVALID_MFN;
ret:
- return map_domain_page(_mfn(mfn)) + (addr & ~PAGE_MASK);
+ return _mfn(mfn);
+}
+
+void *do_page_walk(struct vcpu *v, unsigned long addr)
+{
+ mfn_t mfn;
+ unsigned long cr3;
+
+ if ( !is_pv_vcpu(v) )
+ return NULL;
+
+ cr3 = pagetable_get_pfn(v->arch.guest_table);
+ mfn = _do_page_walk(cr3, addr);
+ if ( mfn_eq(mfn, INVALID_MFN) )
+ return NULL;
+
+ return map_domain_page(mfn) + (addr & ~PAGE_MASK);
}
/*
diff --git a/xen/include/asm-x86/mm.h b/xen/include/asm-x86/mm.h
index bef45e8e9f..224a94494a 100644
--- a/xen/include/asm-x86/mm.h
+++ b/xen/include/asm-x86/mm.h
@@ -540,6 +540,7 @@ int new_guest_cr3(mfn_t mfn);
void make_cr3(struct vcpu *v, mfn_t mfn);
void update_cr3(struct vcpu *v);
int vcpu_destroy_pagetables(struct vcpu *);
+mfn_t _do_page_walk(unsigned long mfn, unsigned long addr);
void *do_page_walk(struct vcpu *v, unsigned long addr);
int __sync_local_execstate(void);
diff --git a/xen/include/xen/livepatch.h b/xen/include/xen/livepatch.h
index 065c1a323a..e529f0e7c3 100644
--- a/xen/include/xen/livepatch.h
+++ b/xen/include/xen/livepatch.h
@@ -72,6 +72,9 @@ int arch_livepatch_secure(const void *va, unsigned int pages,
enum va_type types
void arch_livepatch_init(void);
+#include <xen/mm.h> /* For mfn_t decleration. */
+mfn_t arch_livepatch_lookup_mfn(unsigned long addr);
+
#include <public/sysctl.h> /* For struct livepatch_func. */
#include <asm/livepatch.h>
int arch_livepatch_verify_func(const struct livepatch_func *func);
