[PATCH] uml: fix segfault on exit with CONFIG_GCOV

We need to disable signals on exit in all cases, not just when rebooting.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 20 insertions, 18 deletions

diff --git a/arch/um/kernel/main.c b/arch/um/kernel/main.c
index 939e3b708670..e42e6364ca13 100644
--- a/arch/um/kernel/main.c
+++ b/arch/um/kernel/main.c
@@ -87,7 +87,7 @@ int main(int argc, char **argv, char **envp)
 {
         char **new_argv;
         sigset_t mask;
-        int ret, i;
+        int ret, i, err;
 
         /* Enable all signals except SIGIO - in some environments, we can
          * enter with some signals blocked
@@ -160,27 +160,29 @@ int main(int argc, char **argv, char **envp)
          */
         change_sig(SIGPROF, 0);
 
-        /* Reboot */
-        if(ret){
-                int err;
-
-                printf("\n");
+        /* This signal stuff used to be in the reboot case.  However,
+         * sometimes a SIGVTALRM can come in when we're halting (reproducably
+         * when writing out gcov information, presumably because that takes
+         * some time) and cause a segfault.
+         */
 
-                /* stop timers and set SIG*ALRM to be ignored */
-                disable_timer();
+        /* stop timers and set SIG*ALRM to be ignored */
+        disable_timer();
 
-                /* disable SIGIO for the fds and set SIGIO to be ignored */
-                err = deactivate_all_fds();
-                if(err)
-                        printf("deactivate_all_fds failed, errno = %d\n",
-                               -err);
+        /* disable SIGIO for the fds and set SIGIO to be ignored */
+        err = deactivate_all_fds();
+        if(err)
+                printf("deactivate_all_fds failed, errno = %d\n", -err);
 
-                /* Let any pending signals fire now.  This ensures
-                 * that they won't be delivered after the exec, when
-                 * they are definitely not expected.
-                 */
-                unblock_signals();
+        /* Let any pending signals fire now.  This ensures
+         * that they won't be delivered after the exec, when
+         * they are definitely not expected.
+         */
+        unblock_signals();
 
+        /* Reboot */
+        if(ret){
+                printf("\n");
                 execvp(new_argv[0], new_argv);
                 perror("Failed to exec kernel");
                 ret = 1;