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

Pull x86 fixes from Ingo Molnar:
 "Fixes all around the map: W+X kernel mapping fix, WCHAN fixes, two
  build failure fixes for corner case configs, x32 header fix and a
  speling fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/headers/uapi: Fix __BITS_PER_LONG value for x32 builds
  x86/mm: Set NX on gap between __ex_table and rodata
  x86/kexec: Fix kexec crash in syscall kexec_file_load()
  x86/process: Unify 32bit and 64bit implementations of get_wchan()
  x86/process: Add proper bound checks in 64bit get_wchan()
  x86, efi, kasan: Fix build failure on !KASAN && KMEMCHECK=y kernels
  x86/hyperv: Fix the build in the !CONFIG_KEXEC_CORE case
  x86/cpufeatures: Correct spelling of the HWP_NOTIFY flag

9 files changed, 69 insertions, 65 deletions

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index e6cf2ad350d1..9727b3b48bd1 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -193,7 +193,7 @@
 #define X86_FEATURE_HW_PSTATE   ( 7*32+ 8) /* AMD HW-PState */
 #define X86_FEATURE_PROC_FEEDBACK ( 7*32+ 9) /* AMD ProcFeedbackInterface */
 #define X86_FEATURE_HWP         ( 7*32+ 10) /* "hwp" Intel HWP */
-#define X86_FEATURE_HWP_NOITFY  ( 7*32+ 11) /* Intel HWP_NOTIFY */
+#define X86_FEATURE_HWP_NOTIFY  ( 7*32+ 11) /* Intel HWP_NOTIFY */
 #define X86_FEATURE_HWP_ACT_WINDOW ( 7*32+ 12) /* Intel HWP_ACT_WINDOW */
 #define X86_FEATURE_HWP_EPP     ( 7*32+13) /* Intel HWP_EPP */
 #define X86_FEATURE_HWP_PKG_REQ ( 7*32+14) /* Intel HWP_PKG_REQ */
diff --git a/arch/x86/include/uapi/asm/bitsperlong.h b/arch/x86/include/uapi/asm/bitsperlong.h
index b0ae1c4dc791..217909b4d6f5 100644
--- a/arch/x86/include/uapi/asm/bitsperlong.h
+++ b/arch/x86/include/uapi/asm/bitsperlong.h
@@ -1,7 +1,7 @@
 #ifndef __ASM_X86_BITSPERLONG_H
 #define __ASM_X86_BITSPERLONG_H
 
-#ifdef __x86_64__
+#if defined(__x86_64__) && !defined(__ILP32__)
 # define __BITS_PER_LONG 64
 #else
 # define __BITS_PER_LONG 32
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 381c8b9b3a33..20e242ea1bc4 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -34,11 +34,10 @@
 struct ms_hyperv_info ms_hyperv;
 EXPORT_SYMBOL_GPL(ms_hyperv);
 
-static void (*hv_kexec_handler)(void);
-static void (*hv_crash_handler)(struct pt_regs *regs);
-
 #if IS_ENABLED(CONFIG_HYPERV)
 static void (*vmbus_handler)(void);
+static void (*hv_kexec_handler)(void);
+static void (*hv_crash_handler)(struct pt_regs *regs);
 
 void hyperv_vector_handler(struct pt_regs *regs)
 {
@@ -96,8 +95,8 @@ void hv_remove_crash_handler(void)
         hv_crash_handler = NULL;
 }
 EXPORT_SYMBOL_GPL(hv_remove_crash_handler);
-#endif
 
+#ifdef CONFIG_KEXEC_CORE
 static void hv_machine_shutdown(void)
 {
         if (kexec_in_progress && hv_kexec_handler)
@@ -111,7 +110,8 @@ static void hv_machine_crash_shutdown(struct pt_regs *regs)
                 hv_crash_handler(regs);
         native_machine_crash_shutdown(regs);
 }
-
+#endif /* CONFIG_KEXEC_CORE */
+#endif /* CONFIG_HYPERV */
 
 static uint32_t  __init ms_hyperv_platform(void)
 {
@@ -186,8 +186,10 @@ static void __init ms_hyperv_init_platform(void)
         no_timer_check = 1;
 #endif
 
+#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
         machine_ops.shutdown = hv_machine_shutdown;
         machine_ops.crash_shutdown = hv_machine_crash_shutdown;
+#endif
         mark_tsc_unstable("running on Hyper-V");
 }
 
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 3d423a101fae..608fb26c7254 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -37,7 +37,7 @@ void init_scattered_cpuid_features(struct cpuinfo_x86 *c)
                 { X86_FEATURE_PLN,              CR_EAX, 4, 0x00000006, 0 },
                 { X86_FEATURE_PTS,              CR_EAX, 6, 0x00000006, 0 },
                 { X86_FEATURE_HWP,              CR_EAX, 7, 0x00000006, 0 },
-                { X86_FEATURE_HWP_NOITFY,       CR_EAX, 8, 0x00000006, 0 },
+                { X86_FEATURE_HWP_NOTIFY,       CR_EAX, 8, 0x00000006, 0 },
                 { X86_FEATURE_HWP_ACT_WINDOW,   CR_EAX, 9, 0x00000006, 0 },
                 { X86_FEATURE_HWP_EPP,          CR_EAX,10, 0x00000006, 0 },
                 { X86_FEATURE_HWP_PKG_REQ,      CR_EAX,11, 0x00000006, 0 },
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index e068d6683dba..74ca2fe7a0b3 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -185,10 +185,9 @@ void native_machine_crash_shutdown(struct pt_regs *regs)
 }
 
 #ifdef CONFIG_KEXEC_FILE
-static int get_nr_ram_ranges_callback(unsigned long start_pfn,
-                                unsigned long nr_pfn, void *arg)
+static int get_nr_ram_ranges_callback(u64 start, u64 end, void *arg)
 {
-        int *nr_ranges = arg;
+        unsigned int *nr_ranges = arg;
 
         (*nr_ranges)++;
         return 0;
@@ -214,7 +213,7 @@ static void fill_up_crash_elf_data(struct crash_elf_data *ced,
 
         ced->image = image;
 
-        walk_system_ram_range(0, -1, &nr_ranges,
+        walk_system_ram_res(0, -1, &nr_ranges,
                                 get_nr_ram_ranges_callback);
 
         ced->max_nr_ranges = nr_ranges;
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 6d0e62ae8516..39e585a554b7 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -506,3 +506,58 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
         return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
 }
 
+/*
+ * Called from fs/proc with a reference on @p to find the function
+ * which called into schedule(). This needs to be done carefully
+ * because the task might wake up and we might look at a stack
+ * changing under us.
+ */
+unsigned long get_wchan(struct task_struct *p)
+{
+        unsigned long start, bottom, top, sp, fp, ip;
+        int count = 0;
+
+        if (!p || p == current || p->state == TASK_RUNNING)
+                return 0;
+
+        start = (unsigned long)task_stack_page(p);
+        if (!start)
+                return 0;
+
+        /*
+         * Layout of the stack page:
+         *
+         * ----------- topmax = start + THREAD_SIZE - sizeof(unsigned long)
+         * PADDING
+         * ----------- top = topmax - TOP_OF_KERNEL_STACK_PADDING
+         * stack
+         * ----------- bottom = start + sizeof(thread_info)
+         * thread_info
+         * ----------- start
+         *
+         * The tasks stack pointer points at the location where the
+         * framepointer is stored. The data on the stack is:
+         * ... IP FP ... IP FP
+         *
+         * We need to read FP and IP, so we need to adjust the upper
+         * bound by another unsigned long.
+         */
+        top = start + THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;
+        top -= 2 * sizeof(unsigned long);
+        bottom = start + sizeof(struct thread_info);
+
+        sp = READ_ONCE(p->thread.sp);
+        if (sp < bottom || sp > top)
+                return 0;
+
+        fp = READ_ONCE(*(unsigned long *)sp);
+        do {
+                if (fp < bottom || fp > top)
+                        return 0;
+                ip = READ_ONCE(*(unsigned long *)(fp + sizeof(unsigned long)));
+                if (!in_sched_functions(ip))
+                        return ip;
+                fp = READ_ONCE(*(unsigned long *)fp);
+        } while (count++ < 16 && p->state != TASK_RUNNING);
+        return 0;
+}
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index c13df2c735f8..737527b40e5b 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -324,31 +324,3 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 
         return prev_p;
 }
-
-#define top_esp                (THREAD_SIZE - sizeof(unsigned long))
-#define top_ebp                (THREAD_SIZE - 2*sizeof(unsigned long))
-
-unsigned long get_wchan(struct task_struct *p)
-{
-        unsigned long bp, sp, ip;
-        unsigned long stack_page;
-        int count = 0;
-        if (!p || p == current || p->state == TASK_RUNNING)
-                return 0;
-        stack_page = (unsigned long)task_stack_page(p);
-        sp = p->thread.sp;
-        if (!stack_page || sp < stack_page || sp > top_esp+stack_page)
-                return 0;
-        /* include/asm-i386/system.h:switch_to() pushes bp last. */
-        bp = *(unsigned long *) sp;
-        do {
-                if (bp < stack_page || bp > top_ebp+stack_page)
-                        return 0;
-                ip = *(unsigned long *) (bp+4);
-                if (!in_sched_functions(ip))
-                        return ip;
-                bp = *(unsigned long *) bp;
-        } while (count++ < 16);
-        return 0;
-}
-
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 3c1bbcf12924..b35921a670b2 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -499,30 +499,6 @@ void set_personality_ia32(bool x32)
 }
 EXPORT_SYMBOL_GPL(set_personality_ia32);
 
-unsigned long get_wchan(struct task_struct *p)
-{
-        unsigned long stack;
-        u64 fp, ip;
-        int count = 0;
-
-        if (!p || p == current || p->state == TASK_RUNNING)
-                return 0;
-        stack = (unsigned long)task_stack_page(p);
-        if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE)
-                return 0;
-        fp = *(u64 *)(p->thread.sp);
-        do {
-                if (fp < (unsigned long)stack ||
-                    fp >= (unsigned long)stack+THREAD_SIZE)
-                        return 0;
-                ip = *(u64 *)(fp+8);
-                if (!in_sched_functions(ip))
-                        return ip;
-                fp = *(u64 *)fp;
-        } while (count++ < 16);
-        return 0;
-}
-
 long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 {
         int ret = 0;
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 30564e2752d3..df48430c279b 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1132,7 +1132,7 @@ void mark_rodata_ro(void)
          * has been zapped already via cleanup_highmem().
          */
         all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
-        set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT);
+        set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
 
         rodata_test();