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

Pull x86 fixes from Ingo Molnar:
 "Various fixes:

   - Fix the PAT performance regression that downgraded write-combining
     device memory regions to uncached.

   - There's been a number of bugs in 32-bit double fault handling -
     hopefully all fixed now.

   - Fix an LDT crash

   - Fix an FPU over-optimization that broke with GCC9 code
     optimizations.

   - Misc cleanups"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/pat: Fix off-by-one bugs in interval tree search
  x86/ioperm: Save an indentation level in tss_update_io_bitmap()
  x86/fpu: Don't cache access to fpu_fpregs_owner_ctx
  x86/entry/32: Remove unused 'restore_all_notrace' local label
  x86/ptrace: Document FSBASE and GSBASE ABI oddities
  x86/ptrace: Remove set_segment_reg() implementations for current
  x86/traps: die() instead of panicking on a double fault
  x86/doublefault/32: Rewrite the x86_32 #DF handler and unify with 64-bit
  x86/doublefault/32: Move #DF stack and TSS to cpu_entry_area
  x86/doublefault/32: Rename doublefault.c to doublefault_32.c
  x86/traps: Disentangle the 32-bit and 64-bit doublefault code
  lkdtm: Add a DOUBLE_FAULT crash type on x86
  selftests/x86/single_step_syscall: Check SYSENTER directly
  x86/mm/32: Sync only to VMALLOC_END in vmalloc_sync_all()

3 files changed, 20 insertions, 8 deletions

diff --git a/arch/x86/mm/cpu_entry_area.c b/arch/x86/mm/cpu_entry_area.c
index 82ead8e27888..56f9189bbadb 100644
--- a/arch/x86/mm/cpu_entry_area.c
+++ b/arch/x86/mm/cpu_entry_area.c
@@ -17,6 +17,10 @@ static DEFINE_PER_CPU_PAGE_ALIGNED(struct exception_stacks, exception_stacks);
 DEFINE_PER_CPU(struct cea_exception_stacks*, cea_exception_stacks);
 #endif
 
+#if defined(CONFIG_X86_32) && defined(CONFIG_DOUBLEFAULT)
+DECLARE_PER_CPU_PAGE_ALIGNED(struct doublefault_stack, doublefault_stack);
+#endif
+
 struct cpu_entry_area *get_cpu_entry_area(int cpu)
 {
 	unsigned long va = CPU_ENTRY_AREA_PER_CPU + cpu * CPU_ENTRY_AREA_SIZE;
@@ -108,7 +112,15 @@ static void __init percpu_setup_exception_stacks(unsigned int cpu)
 	cea_map_stack(MCE);
 }
 #else
-static inline void percpu_setup_exception_stacks(unsigned int cpu) {}
+static inline void percpu_setup_exception_stacks(unsigned int cpu)
+{
+#ifdef CONFIG_DOUBLEFAULT
+	struct cpu_entry_area *cea = get_cpu_entry_area(cpu);
+
+	cea_map_percpu_pages(&cea->doublefault_stack,
+			     &per_cpu(doublefault_stack, cpu), 1, PAGE_KERNEL);
+#endif
+}
 #endif
 
 /* Setup the fixmap mappings only once per-processor */
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 9ceacd1156db..304d31d8cbbc 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -197,7 +197,7 @@ void vmalloc_sync_all(void)
 		return;
 
 	for (address = VMALLOC_START & PMD_MASK;
-	     address >= TASK_SIZE_MAX && address < FIXADDR_TOP;
+	     address >= TASK_SIZE_MAX && address < VMALLOC_END;
 	     address += PMD_SIZE) {
 		struct page *page;
 
diff --git a/arch/x86/mm/pat_interval.c b/arch/x86/mm/pat_interval.c
index 47a1bf30748f..6855362eaf21 100644
--- a/arch/x86/mm/pat_interval.c
+++ b/arch/x86/mm/pat_interval.c
@@ -56,7 +56,7 @@ static struct memtype *memtype_match(u64 start, u64 end, int match_type)
 {
 	struct memtype *match;
 
-	match = memtype_interval_iter_first(&memtype_rbroot, start, end);
+	match = memtype_interval_iter_first(&memtype_rbroot, start, end-1);
 	while (match != NULL && match->start < end) {
 		if ((match_type == MEMTYPE_EXACT_MATCH) &&
 		    (match->start == start) && (match->end == end))
@@ -66,7 +66,7 @@ static struct memtype *memtype_match(u64 start, u64 end, int match_type)
 		    (match->start < start) && (match->end == end))
 			return match;
 
-		match = memtype_interval_iter_next(match, start, end);
+		match = memtype_interval_iter_next(match, start, end-1);
 	}
 
 	return NULL; /* Returns NULL if there is no match */
@@ -79,7 +79,7 @@ static int memtype_check_conflict(u64 start, u64 end,
 	struct memtype *match;
 	enum page_cache_mode found_type = reqtype;
 
-	match = memtype_interval_iter_first(&memtype_rbroot, start, end);
+	match = memtype_interval_iter_first(&memtype_rbroot, start, end-1);
 	if (match == NULL)
 		goto success;
 
@@ -89,12 +89,12 @@ static int memtype_check_conflict(u64 start, u64 end,
 	dprintk("Overlap at 0x%Lx-0x%Lx\n", match->start, match->end);
 	found_type = match->type;
 
-	match = memtype_interval_iter_next(match, start, end);
+	match = memtype_interval_iter_next(match, start, end-1);
 	while (match) {
 		if (match->type != found_type)
 			goto failure;
 
-		match = memtype_interval_iter_next(match, start, end);
+		match = memtype_interval_iter_next(match, start, end-1);
 	}
 success:
 	if (newtype)
@@ -160,7 +160,7 @@ struct memtype *memtype_erase(u64 start, u64 end)
 struct memtype *memtype_lookup(u64 addr)
 {
 	return memtype_interval_iter_first(&memtype_rbroot, addr,
-					   addr + PAGE_SIZE);
+					   addr + PAGE_SIZE-1);
 }
 
 #if defined(CONFIG_DEBUG_FS)