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

Pull x86 stackdump update from Ingo Molnar:
 "A number of stackdump enhancements"

* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/dumpstack: Add show_stack_regs() and use it
  printk: Make the printk*once() variants return a value
  x86/dumpstack: Honor supplied @regs arg

1 files changed, 8 insertions, 5 deletions

diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 0f90cc218d04..832b98f822be 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -1,6 +1,7 @@
 #include <linux/module.h>
 #include <asm/uaccess.h>
 #include <asm/traps.h>
+#include <asm/kdebug.h>
 
 typedef bool (*ex_handler_t)(const struct exception_table_entry *,
                             struct pt_regs *, int);
@@ -46,8 +47,9 @@ EXPORT_SYMBOL(ex_handler_ext);
 bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup,
                              struct pt_regs *regs, int trapnr)
 {
-        WARN_ONCE(1, "unchecked MSR access error: RDMSR from 0x%x\n",
-                  (unsigned int)regs->cx);
+        if (pr_warn_once("unchecked MSR access error: RDMSR from 0x%x at rIP: 0x%lx (%pF)\n",
+                         (unsigned int)regs->cx, regs->ip, (void *)regs->ip))
+                show_stack_regs(regs);
 
         /* Pretend that the read succeeded and returned 0. */
         regs->ip = ex_fixup_addr(fixup);
@@ -60,9 +62,10 @@ EXPORT_SYMBOL(ex_handler_rdmsr_unsafe);
 bool ex_handler_wrmsr_unsafe(const struct exception_table_entry *fixup,
                              struct pt_regs *regs, int trapnr)
 {
-        WARN_ONCE(1, "unchecked MSR access error: WRMSR to 0x%x (tried to write 0x%08x%08x)\n",
-                  (unsigned int)regs->cx,
-                  (unsigned int)regs->dx, (unsigned int)regs->ax);
+        if (pr_warn_once("unchecked MSR access error: WRMSR to 0x%x (tried to write 0x%08x%08x) at rIP: 0x%lx (%pF)\n",
+                         (unsigned int)regs->cx, (unsigned int)regs->dx,
+                         (unsigned int)regs->ax,  regs->ip, (void *)regs->ip))
+                show_stack_regs(regs);
 
         /* Pretend that the write succeeded. */
         regs->ip = ex_fixup_addr(fixup);