x86/dumpstack: Unify show_regs()

The 32-bit version uses KERN_EMERG and commit

  b0f4c4b32c8e ("bugs, x86: Fix printk levels for panic, softlockups and stack dumps")

changed the 64-bit version to KERN_DEFAULT. The same justification in
that commit that those messages do not belong in the terminal, holds
true for 32-bit also, so make it so.

Make code_bytes static, while at it.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180306094920.16917-4-bp@alien8.de

diff --git a/arch/x86/include/asm/stacktrace.h b/arch/x86/include/asm/stacktrace.h
index f737068787729f045a578776845231b0a0ee3e0d..133d9425fced99a50dadd6cdf11b7597ac67c175 100644 (file)
--- a/arch/x86/include/asm/stacktrace.h
+++ b/arch/x86/include/asm/stacktrace.h
@@ -87,8 +87,6 @@ get_stack_pointer(struct task_struct *task, struct pt_regs *regs)
 void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
                        unsigned long *stack, char *log_lvl);
 
-extern unsigned int code_bytes;
-
 /* The form of the top of the frame on the stack */
 struct stack_frame {
        struct stack_frame *next_frame;

diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index a2d8a3908670993c898cd0d22cbdd6742e51b4da..18fa9d74c18246a572c5a74787c60925c205bb60 100644 (file)
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -24,7 +24,7 @@
 
 int panic_on_unrecovered_nmi;
 int panic_on_io_nmi;
-unsigned int code_bytes = 64;
+static unsigned int code_bytes = 64;
 static int die_counter;
 
 bool in_task_stack(unsigned long *stack, struct task_struct *task,
@@ -375,3 +375,50 @@ static int __init code_bytes_setup(char *s)
        return 1;
 }
 __setup("code_bytes=", code_bytes_setup);
+
+void show_regs(struct pt_regs *regs)
+{
+       bool all = true;
+       int i;
+
+       show_regs_print_info(KERN_DEFAULT);
+
+       if (IS_ENABLED(CONFIG_X86_32))
+               all = !user_mode(regs);
+
+       __show_regs(regs, all);
+
+       /*
+        * When in-kernel, we also print out the stack and code at the
+        * time of the fault..
+        */
+       if (!user_mode(regs)) {
+               unsigned int code_prologue = code_bytes * 43 / 64;
+               unsigned int code_len = code_bytes;
+               unsigned char c;
+               u8 *ip;
+
+               show_trace_log_lvl(current, regs, NULL, KERN_DEFAULT);
+
+               printk(KERN_DEFAULT "Code: ");
+
+               ip = (u8 *)regs->ip - code_prologue;
+               if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
+                       /* try starting at IP */
+                       ip = (u8 *)regs->ip;
+                       code_len = code_len - code_prologue + 1;
+               }
+               for (i = 0; i < code_len; i++, ip++) {
+                       if (ip < (u8 *)PAGE_OFFSET ||
+                                       probe_kernel_address(ip, c)) {
+                               pr_cont(" Bad RIP value.");
+                               break;
+                       }
+                       if (ip == (u8 *)regs->ip)
+                               pr_cont("<%02x> ", c);
+                       else
+                               pr_cont("%02x ", c);
+               }
+       }
+       pr_cont("\n");
+}

diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
index 04170f63e3a1d567caac3deea641e014b7e10823..cd53f3030e4004e89d7d027cee217fb8e0ea08a7 100644 (file)
--- a/arch/x86/kernel/dumpstack_32.c
+++ b/arch/x86/kernel/dumpstack_32.c
@@ -127,45 +127,3 @@ unknown:
        info->type = STACK_TYPE_UNKNOWN;
        return -EINVAL;
 }
-
-void show_regs(struct pt_regs *regs)
-{
-       int i;
-
-       show_regs_print_info(KERN_EMERG);
-       __show_regs(regs, !user_mode(regs));
-
-       /*
-        * When in-kernel, we also print out the stack and code at the
-        * time of the fault..
-        */
-       if (!user_mode(regs)) {
-               unsigned int code_prologue = code_bytes * 43 / 64;
-               unsigned int code_len = code_bytes;
-               unsigned char c;
-               u8 *ip;
-
-               show_trace_log_lvl(current, regs, NULL, KERN_EMERG);
-
-               pr_emerg("Code:");
-
-               ip = (u8 *)regs->ip - code_prologue;
-               if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
-                       /* try starting at IP */
-                       ip = (u8 *)regs->ip;
-                       code_len = code_len - code_prologue + 1;
-               }
-               for (i = 0; i < code_len; i++, ip++) {
-                       if (ip < (u8 *)PAGE_OFFSET ||
-                                       probe_kernel_address(ip, c)) {
-                               pr_cont("  Bad EIP value.");
-                               break;
-                       }
-                       if (ip == (u8 *)regs->ip)
-                               pr_cont(" <%02x>", c);
-                       else
-                               pr_cont(" %02x", c);
-               }
-       }
-       pr_cont("\n");
-}

diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 563e28d14f2ca157178d9de3a139d8370aaf89fe..5cdb9e84da57db3d4a494fdd41805219303bd7b6 100644 (file)
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -149,45 +149,3 @@ unknown:
        info->type = STACK_TYPE_UNKNOWN;
        return -EINVAL;
 }
-
-void show_regs(struct pt_regs *regs)
-{
-       int i;
-
-       show_regs_print_info(KERN_DEFAULT);
-       __show_regs(regs, 1);
-
-       /*
-        * When in-kernel, we also print out the stack and code at the
-        * time of the fault..
-        */
-       if (!user_mode(regs)) {
-               unsigned int code_prologue = code_bytes * 43 / 64;
-               unsigned int code_len = code_bytes;
-               unsigned char c;
-               u8 *ip;
-
-               show_trace_log_lvl(current, regs, NULL, KERN_DEFAULT);
-
-               printk(KERN_DEFAULT "Code: ");
-
-               ip = (u8 *)regs->ip - code_prologue;
-               if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
-                       /* try starting at IP */
-                       ip = (u8 *)regs->ip;
-                       code_len = code_len - code_prologue + 1;
-               }
-               for (i = 0; i < code_len; i++, ip++) {
-                       if (ip < (u8 *)PAGE_OFFSET ||
-                                       probe_kernel_address(ip, c)) {
-                               pr_cont(" Bad RIP value.");
-                               break;
-                       }
-                       if (ip == (u8 *)regs->ip)
-                               pr_cont("<%02x> ", c);
-                       else
-                               pr_cont("%02x ", c);
-               }
-       }
-       pr_cont("\n");
-}