uml: dump core on panic

Dump core after a panic.  This will provide better debugging information than
is currently available.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 8 insertions, 1 deletions

diff --git a/arch/um/include/os.h b/arch/um/include/os.h
index b463170a5308..901804db3c35 100644
--- a/arch/um/include/os.h
+++ b/arch/um/include/os.h
@@ -279,6 +279,7 @@ extern int raw(int fd);
 extern void setup_machinename(char *machine_out);
 extern void setup_hostinfo(char *buf, int len);
 extern int setjmp_wrapper(void (*proc)(void *, void *), ...);
+extern void os_dump_core(void);
 
 /* time.c */
 #define BILLION (1000 * 1000 * 1000)
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 9bf31533a8fd..1cf954a47fd7 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -474,7 +474,7 @@ static int panic_exit(struct notifier_block *self, unsigned long unused1,
         show_regs(&(current->thread.regs));
         bust_spinlocks(0);
         uml_exitcode = 1;
-        machine_halt();
+        os_dump_core();
         return 0;
 }
 
diff --git a/arch/um/os-Linux/util.c b/arch/um/os-Linux/util.c
index 48bc4927b996..c307a89ed259 100644
--- a/arch/um/os-Linux/util.c
+++ b/arch/um/os-Linux/util.c
@@ -119,3 +119,9 @@ int setjmp_wrapper(void (*proc)(void *, void *), ...)
         va_end(args);
         return n;
 }
+
+void os_dump_core(void)
+{
+        signal(SIGSEGV, SIG_DFL);
+        abort();
+}