![]() | |||||||||||
Messages in this thread
Patch in this message |
2.6.26 -stable review patch. If anyone has any objections, please let us know. ------------------ From: Avi Kivity <avi@qumranet.com> Original-Commit-Hash: c23a6fe17abf8562e675465f8d55ba1a551d314d The direct mapped shadow code (used for real mode and two dimensional paging) sets upper-level ptes using direct assignment rather than calling set_shadow_pte(). A nonpae host will split this into two writes, which opens up a race if another vcpu accesses the same memory area. Fix by calling set_shadow_pte() instead of assigning directly. Noticed by Izik Eidus. Signed-off-by: Avi Kivity <avi@qumranet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- arch/x86/kvm/mmu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1171,9 +1171,10 @@ static int __direct_map(struct kvm_vcpu return -ENOMEM; } - table[index] = __pa(new_table->spt) - | PT_PRESENT_MASK | PT_WRITABLE_MASK - | shadow_user_mask | shadow_x_mask; + set_shadow_pte(&table[index], + __pa(new_table->spt) + | PT_PRESENT_MASK | PT_WRITABLE_MASK + | shadow_user_mask | shadow_x_mask); } table_addr = table[index] & PT64_BASE_ADDR_MASK; } -- | ||||||||||
| Last update: 2008-07-31 02:11 [from the cache] ©2003-2008 | |||||||||||