diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index b1ed0a1a5913..b666d8d106a9 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -1960,6 +1961,27 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, return pt_write; } +static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn) +{ + char buf[1]; + void __user *hva; + int r; + + /* Touch the page, so send SIGBUS */ + hva = (void __user *)gfn_to_hva(kvm, gfn); + r = copy_from_user(buf, hva, 1); +} + +static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn) +{ + kvm_release_pfn_clean(pfn); + if (is_hwpoison_pfn(pfn)) { + kvm_send_hwpoison_signal(kvm, gfn); + return 0; + } + return 1; +} + static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn) { int r; @@ -1983,10 +2005,8 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn) pfn = gfn_to_pfn(vcpu->kvm, gfn); /* mmio */ - if (is_error_pfn(pfn)) { - kvm_release_pfn_clean(pfn); - return 1; - } + if (is_error_pfn(pfn)) + return kvm_handle_bad_page(vcpu->kvm, gfn, pfn); spin_lock(&vcpu->kvm->mmu_lock); if (mmu_notifier_retry(vcpu, mmu_seq)) @@ -2198,10 +2218,8 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); pfn = gfn_to_pfn(vcpu->kvm, gfn); - if (is_error_pfn(pfn)) { - kvm_release_pfn_clean(pfn); - return 1; - } + if (is_error_pfn(pfn)) + return kvm_handle_bad_page(vcpu->kvm, gfn, pfn); spin_lock(&vcpu->kvm->mmu_lock); if (mmu_notifier_retry(vcpu, mmu_seq)) goto out_unlock; diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 2331bdc2b549..c7f27779c998 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -431,11 +431,8 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, pfn = gfn_to_pfn(vcpu->kvm, walker.gfn); /* mmio */ - if (is_error_pfn(pfn)) { - pgprintk("gfn %lx is mmio\n", walker.gfn); - kvm_release_pfn_clean(pfn); - return 1; - } + if (is_error_pfn(pfn)) + return kvm_handle_bad_page(vcpu->kvm, walker.gfn, pfn); spin_lock(&vcpu->kvm->mmu_lock); if (mmu_notifier_retry(vcpu, mmu_seq)) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7cb116afa1cd..a0e019769f5d 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -266,6 +266,7 @@ extern pfn_t bad_pfn; int is_error_page(struct page *page); int is_error_pfn(pfn_t pfn); +int is_hwpoison_pfn(pfn_t pfn); int kvm_is_error_hva(unsigned long addr); int kvm_set_memory_region(struct kvm *kvm, struct kvm_userspace_memory_region *mem, diff --git a/include/linux/mm.h b/include/linux/mm.h index a2b48041b910..7a9ab7db1975 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1465,6 +1465,14 @@ extern int sysctl_memory_failure_recovery; extern void shake_page(struct page *p, int access); extern atomic_long_t mce_bad_pages; extern int soft_offline_page(struct page *page, int flags); +#ifdef CONFIG_MEMORY_FAILURE +int is_hwpoison_address(unsigned long addr); +#else +static inline int is_hwpoison_address(unsigned long addr) +{ + return 0; +} +#endif extern void dump_page(struct page *page); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 620b0b461593..378b0f61fd3c 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -45,6 +45,7 @@ #include #include #include +#include #include "internal.h" int sysctl_memory_failure_early_kill __read_mostly = 0; @@ -1296,3 +1297,32 @@ done: /* keep elevated page count for bad page */ return ret; } + +int is_hwpoison_address(unsigned long addr) +{ + pgd_t *pgdp; + pud_t pud, *pudp; + pmd_t pmd, *pmdp; + pte_t pte, *ptep; + swp_entry_t entry; + + pgdp = pgd_offset(current->mm, addr); + if (!pgd_present(*pgdp)) + return 0; + pudp = pud_offset(pgdp, addr); + pud = *pudp; + if (!pud_present(pud) || pud_large(pud)) + return 0; + pmdp = pmd_offset(pudp, addr); + pmd = *pmdp; + if (!pmd_present(pmd) || pmd_large(pmd)) + return 0; + ptep = pte_offset_map(pmdp, addr); + pte = *ptep; + pte_unmap(ptep); + if (!is_swap_pte(pte)) + return 0; + entry = pte_to_swp_entry(pte); + return is_hwpoison_entry(entry); +} +EXPORT_SYMBOL_GPL(is_hwpoison_address); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f032806a212f..187aa8d984a7 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -92,6 +92,9 @@ static bool kvm_rebooting; static bool largepages_enabled = true; +struct page *hwpoison_page; +pfn_t hwpoison_pfn; + inline int kvm_is_mmio_pfn(pfn_t pfn) { if (pfn_valid(pfn)) { @@ -810,16 +813,22 @@ EXPORT_SYMBOL_GPL(kvm_disable_largepages); int is_error_page(struct page *page) { - return page == bad_page; + return page == bad_page || page == hwpoison_page; } EXPORT_SYMBOL_GPL(is_error_page); int is_error_pfn(pfn_t pfn) { - return pfn == bad_pfn; + return pfn == bad_pfn || pfn == hwpoison_pfn; } EXPORT_SYMBOL_GPL(is_error_pfn); +int is_hwpoison_pfn(pfn_t pfn) +{ + return pfn == hwpoison_pfn; +} +EXPORT_SYMBOL_GPL(is_hwpoison_pfn); + static inline unsigned long bad_hva(void) { return PAGE_OFFSET; @@ -945,6 +954,11 @@ static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr) if (unlikely(npages != 1)) { struct vm_area_struct *vma; + if (is_hwpoison_address(addr)) { + get_page(hwpoison_page); + return page_to_pfn(hwpoison_page); + } + down_read(¤t->mm->mmap_sem); vma = find_vma(current->mm, addr); @@ -2197,6 +2211,15 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, bad_pfn = page_to_pfn(bad_page); + hwpoison_page = alloc_page(GFP_KERNEL | __GFP_ZERO); + + if (hwpoison_page == NULL) { + r = -ENOMEM; + goto out_free_0; + } + + hwpoison_pfn = page_to_pfn(hwpoison_page); + if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) { r = -ENOMEM; goto out_free_0; @@ -2269,6 +2292,8 @@ out_free_1: out_free_0a: free_cpumask_var(cpus_hardware_enabled); out_free_0: + if (hwpoison_page) + __free_page(hwpoison_page); __free_page(bad_page); out: kvm_arch_exit(); @@ -2290,6 +2315,7 @@ void kvm_exit(void) kvm_arch_hardware_unsetup(); kvm_arch_exit(); free_cpumask_var(cpus_hardware_enabled); + __free_page(hwpoison_page); __free_page(bad_page); } EXPORT_SYMBOL_GPL(kvm_exit);