| Message ID | 1236255153-4432-7-git-send-email-joerg.roedel@amd.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
Joerg Roedel wrote: > We also need to do a remote tlb flush if the PSE bit changes. The > pte_pfn should also change if this bit changes but we can't rely on > that. So check this bit too to be on the save side. > > Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> > --- > arch/x86/kvm/mmu.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 2a36f7f..055b181 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -121,7 +121,7 @@ module_param(oos_shadow, bool, 0644); > (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1)) > > #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \ > - | PT64_NX_MASK) > + | PT64_NX_MASK | PT_PAGE_SIZE_MASK) > > PT64_PERM_MASK is used in this way: static bool need_remote_flush(u64 old, u64 new) { if (!is_shadow_present_pte(old)) return false; if (!is_shadow_present_pte(new)) return true; if ((old ^ new) & PT64_BASE_ADDR_MASK) return true; old ^= PT64_NX_MASK; new ^= PT64_NX_MASK; return (old & ~new & PT64_PERM_MASK) != 0; } We don't check whether a bit changes, rather we check if a bit is turned off (or on in the case of nx). But I think we need a tlb flush even if we change PSE from 0 to 1. Thinking a bit more, this will never trigger, since an spte at a particular level cannot have its pse bit changed (at least in kvm_mmu_pte_write).
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 2a36f7f..055b181 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -121,7 +121,7 @@ module_param(oos_shadow, bool, 0644); (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1)) #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \ - | PT64_NX_MASK) + | PT64_NX_MASK | PT_PAGE_SIZE_MASK) #define PFERR_PRESENT_MASK (1U << 0) #define PFERR_WRITE_MASK (1U << 1)
We also need to do a remote tlb flush if the PSE bit changes. The pte_pfn should also change if this bit changes but we can't rely on that. So check this bit too to be on the save side. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> --- arch/x86/kvm/mmu.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)