[PATCH] kdump: Save trap information for later analysis

If we are faulting in kernel it is quite possible this will lead to a
panic.  Save trap number, cr2 (in case of page fault) and error_code in the
current thread (these fields already exist for signal delivery but are not
used here).

This helps later kdump crash analyzing from user-space (a script has been
submitted to dig this info out in gdb).

Signed-off-by: Alexander Nyberg <alexn@telia.com>
Cc: <fastboot@lists.osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c
index a509237c4815..92ed6c0a55da 100644
--- a/arch/i386/mm/fault.c
+++ b/arch/i386/mm/fault.c
@@ -463,6 +463,9 @@ no_context:
                 printk(KERN_ALERT "*pte = %08lx\n", page);
         }
 #endif
+        tsk->thread.cr2 = address;
+        tsk->thread.trap_no = 14;
+        tsk->thread.error_code = error_code;
         die("Oops", regs, error_code);
         bust_spinlocks(0);
         do_exit(SIGKILL);