x86: print which shared library/executable faulted in segfault etc. messages v3

They now look like:

hal-resmgr[13791]: segfault at 3c rip 2b9c8caec182 rsp 7fff1e825d30 error 4 in libacl.so.1.1.0[2b9c8caea000+6000]

This makes it easier to pinpoint bugs to specific libraries.

And printing the offset into a mapping also always allows to find the
correct fault point in a library even with randomized mappings. Previously
there was no way to actually find the correct code address inside
the randomized mapping.

Relies on earlier patch to shorten the printk formats.

They are often now longer than 80 characters, but I think that's worth it.

[includes fix from Eric Dumazet to check d_path error value]

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 4eb751c60390..7347bb14e306 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -484,9 +484,12 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
 void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
 { 
         struct task_struct *me = current; 
-        if (show_unhandled_signals && printk_ratelimit())
-                printk("%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx\n",
+        if (show_unhandled_signals && printk_ratelimit()) {
+                printk("%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx",
                me->comm,me->pid,where,frame,regs->ip,regs->sp,regs->orig_ax);
+                print_vma_addr(" in ", regs->ip);
+                printk("\n");
+        }
 
         force_sig(SIGSEGV, me); 
 }