Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
 "Misc fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Flush lazy MMU when DEBUG_PAGEALLOC is set
  x86/mm/cpa/selftest: Fix false positive in CPA self test
  x86/mm/cpa: Convert noop to functional fix
  x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metal
  x86, mm, paravirt: Fix vmalloc_fault oops during lazy MMU updates

8 files changed, 33 insertions, 21 deletions

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 5edd1742cfd0..7361e47db79f 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -703,7 +703,10 @@ static inline void arch_leave_lazy_mmu_mode(void)
         PVOP_VCALL0(pv_mmu_ops.lazy_mode.leave);
 }
 
-void arch_flush_lazy_mmu_mode(void);
+static inline void arch_flush_lazy_mmu_mode(void)
+{
+        PVOP_VCALL0(pv_mmu_ops.lazy_mode.flush);
+}
 
 static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
                                 phys_addr_t phys, pgprot_t flags)
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 142236ed83af..b3b0ec1dac86 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -91,6 +91,7 @@ struct pv_lazy_ops {
         /* Set deferred update mode, used for batching operations. */
         void (*enter)(void);
         void (*leave)(void);
+        void (*flush)(void);
 };
 
 struct pv_time_ops {
@@ -679,6 +680,7 @@ void paravirt_end_context_switch(struct task_struct *next);
 
 void paravirt_enter_lazy_mmu(void);
 void paravirt_leave_lazy_mmu(void);
+void paravirt_flush_lazy_mmu(void);
 
 void _paravirt_nop(void);
 u32 _paravirt_ident_32(u32);
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 17fff18a1031..8bfb335f74bb 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -263,6 +263,18 @@ void paravirt_leave_lazy_mmu(void)
         leave_lazy(PARAVIRT_LAZY_MMU);
 }
 
+void paravirt_flush_lazy_mmu(void)
+{
+        preempt_disable();
+
+        if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
+                arch_leave_lazy_mmu_mode();
+                arch_enter_lazy_mmu_mode();
+        }
+
+        preempt_enable();
+}
+
 void paravirt_start_context_switch(struct task_struct *prev)
 {
         BUG_ON(preemptible());
@@ -292,18 +304,6 @@ enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
         return this_cpu_read(paravirt_lazy_mode);
 }
 
-void arch_flush_lazy_mmu_mode(void)
-{
-        preempt_disable();
-
-        if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
-                arch_leave_lazy_mmu_mode();
-                arch_enter_lazy_mmu_mode();
-        }
-
-        preempt_enable();
-}
-
 struct pv_info pv_info = {
         .name = "bare hardware",
         .paravirt_enabled = 0,
@@ -475,6 +475,7 @@ struct pv_mmu_ops pv_mmu_ops = {
         .lazy_mode = {
                 .enter = paravirt_nop,
                 .leave = paravirt_nop,
+                .flush = paravirt_nop,
         },
 
         .set_fixmap = native_set_fixmap,
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 1cbd89ca5569..7114c63f047d 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -1334,6 +1334,7 @@ __init void lguest_init(void)
         pv_mmu_ops.read_cr3 = lguest_read_cr3;
         pv_mmu_ops.lazy_mode.enter = paravirt_enter_lazy_mmu;
         pv_mmu_ops.lazy_mode.leave = lguest_leave_lazy_mmu_mode;
+        pv_mmu_ops.lazy_mode.flush = paravirt_flush_lazy_mmu;
         pv_mmu_ops.pte_update = lguest_pte_update;
         pv_mmu_ops.pte_update_defer = lguest_pte_update;
 
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 2b97525246d4..0e883364abb5 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -378,10 +378,12 @@ static noinline __kprobes int vmalloc_fault(unsigned long address)
         if (pgd_none(*pgd_ref))
                 return -1;
 
-        if (pgd_none(*pgd))
+        if (pgd_none(*pgd)) {
                 set_pgd(pgd, *pgd_ref);
-        else
+                arch_flush_lazy_mmu_mode();
+        } else {
                 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
+        }
 
         /*
          * Below here mismatches are bugs because these lower tables
diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pageattr-test.c
index b0086567271c..0e38951e65eb 100644
--- a/arch/x86/mm/pageattr-test.c
+++ b/arch/x86/mm/pageattr-test.c
@@ -68,7 +68,7 @@ static int print_split(struct split_state *s)
                         s->gpg++;
                         i += GPS/PAGE_SIZE;
                 } else if (level == PG_LEVEL_2M) {
-                        if (!(pte_val(*pte) & _PAGE_PSE)) {
+                        if ((pte_val(*pte) & _PAGE_PRESENT) && !(pte_val(*pte) & _PAGE_PSE)) {
                                 printk(KERN_ERR
                                         "%lx level %d but not PSE %Lx\n",
                                         addr, level, (u64)pte_val(*pte));
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 091934e1d0d9..fb4e73ec24d8 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -467,7 +467,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
          * We are safe now. Check whether the new pgprot is the same:
          */
         old_pte = *kpte;
-        old_prot = new_prot = req_prot = pte_pgprot(old_pte);
+        old_prot = req_prot = pte_pgprot(old_pte);
 
         pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr);
         pgprot_val(req_prot) |= pgprot_val(cpa->mask_set);
@@ -478,12 +478,12 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
          * a non present pmd. The canon_pgprot will clear _PAGE_GLOBAL
          * for the ancient hardware that doesn't support it.
          */
-        if (pgprot_val(new_prot) & _PAGE_PRESENT)
-                pgprot_val(new_prot) |= _PAGE_PSE | _PAGE_GLOBAL;
+        if (pgprot_val(req_prot) & _PAGE_PRESENT)
+                pgprot_val(req_prot) |= _PAGE_PSE | _PAGE_GLOBAL;
         else
-                pgprot_val(new_prot) &= ~(_PAGE_PSE | _PAGE_GLOBAL);
+                pgprot_val(req_prot) &= ~(_PAGE_PSE | _PAGE_GLOBAL);
 
-        new_prot = canon_pgprot(new_prot);
+        req_prot = canon_pgprot(req_prot);
 
         /*
          * old_pte points to the large page base address. So we need
@@ -1413,6 +1413,8 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
          * but that can deadlock->flush only current cpu:
          */
         __flush_tlb_all();
+
+        arch_flush_lazy_mmu_mode();
 }
 
 #ifdef CONFIG_HIBERNATION
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index a4ea92477e01..e006c18d288a 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -2200,6 +2200,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
         .lazy_mode = {
                 .enter = paravirt_enter_lazy_mmu,
                 .leave = xen_leave_lazy_mmu,
+                .flush = paravirt_flush_lazy_mmu,
         },
 
         .set_fixmap = xen_set_fixmap,