Only test present bit is not enough since mmio spte is also set this bit, use is_shadow_present_pte() instead of it
Also move the BUG_ONs to the common function to cleanup the code Signed-off-by: Xiao Guangrong <[email protected]> --- arch/x86/kvm/mmu.c | 38 ++++++++++++++++++++------------------ 1 files changed, 20 insertions(+), 18 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index aee13c6..91518b6 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -993,17 +993,25 @@ struct rmap_iterator { */ static u64 *rmap_get_first(unsigned long rmap, struct rmap_iterator *iter) { + u64 *sptep; + if (!rmap) return NULL; if (!(rmap & 1)) { iter->desc = NULL; - return (u64 *)rmap; + sptep = (u64 *)rmap; + + goto exit; } iter->desc = (struct pte_list_desc *)(rmap & ~1ul); iter->pos = 0; - return iter->desc->sptes[iter->pos]; + sptep = iter->desc->sptes[iter->pos]; + +exit: + WARN_ON(sptep && !is_shadow_present_pte(*sptep)); + return sptep; } /* @@ -1013,14 +1021,14 @@ static u64 *rmap_get_first(unsigned long rmap, struct rmap_iterator *iter) */ static u64 *rmap_get_next(struct rmap_iterator *iter) { + u64 *sptep = NULL; + if (iter->desc) { if (iter->pos < PTE_LIST_EXT - 1) { - u64 *sptep; - ++iter->pos; sptep = iter->desc->sptes[iter->pos]; if (sptep) - return sptep; + goto exit; } iter->desc = iter->desc->more; @@ -1028,11 +1036,14 @@ static u64 *rmap_get_next(struct rmap_iterator *iter) if (iter->desc) { iter->pos = 0; /* desc->sptes[0] cannot be NULL */ - return iter->desc->sptes[iter->pos]; + sptep = iter->desc->sptes[iter->pos]; + goto exit; } } - return NULL; +exit: + WARN_ON(sptep && !is_shadow_present_pte(*sptep)); + return sptep; } static void drop_spte(struct kvm *kvm, u64 *sptep) @@ -1048,7 +1059,6 @@ static int __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, int level int write_protected = 0; for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); rmap_printk("rmap_write_protect: spte %p %llx\n", sptep, *sptep); if (!is_writable_pte(*sptep)) { @@ -1123,7 +1133,6 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, int need_tlb_flush = 0; while ((sptep = rmap_get_first(*rmapp, &iter))) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", sptep, *sptep); drop_spte(kvm, sptep); @@ -1147,7 +1156,6 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, new_pfn = pte_pfn(*ptep); for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!is_shadow_present_pte(*sptep)); rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", sptep, *sptep); need_flush = 1; @@ -1242,14 +1250,11 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, return kvm_unmap_rmapp(kvm, rmapp, data); for (sptep = rmap_get_first(*rmapp, &iter); sptep; - sptep = rmap_get_next(&iter)) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); - + sptep = rmap_get_next(&iter)) if (*sptep & PT_ACCESSED_MASK) { young = 1; clear_bit(PT_ACCESSED_SHIFT, (unsigned long *)sptep); } - } return young; } @@ -1270,14 +1275,11 @@ static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp, goto out; for (sptep = rmap_get_first(*rmapp, &iter); sptep; - sptep = rmap_get_next(&iter)) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); - + sptep = rmap_get_next(&iter)) if (*sptep & PT_ACCESSED_MASK) { young = 1; break; } - } out: return young; } -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
