[PATCH] uml: Move signal handlers to arch code

Have most signals go through an arch-provided handler which recovers the
sigcontext and then calls a generic handler.  This replaces the
ARCH_GET_SIGCONTEXT macro, which was somewhat fragile.  On x86_64, recovering
%rdx (which holds the sigcontext pointer) must be the first thing that
happens.  sig_handler duly invokes that first, but there is no guarantee that
I can see that instructions won't be reordered such that %rdx is used before
that.  Having the arch provide the handler seems much more robust.

Some signals in some parts of UML require their own handlers - these places
don't call set_handler any more.  They call sigaction or signal themselves.

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, 2 insertions, 2 deletions

diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
index 4ae73c0e5485..7f5ebbadca63 100644
--- a/arch/um/os-Linux/time.c
+++ b/arch/um/os-Linux/time.c
@@ -40,8 +40,8 @@ void disable_timer(void)
                 printk("disnable_timer - setitimer failed, errno = %d\n",
                        errno);
         /* If there are signals already queued, after unblocking ignore them */
-        set_handler(SIGALRM, SIG_IGN, 0, -1);
-        set_handler(SIGVTALRM, SIG_IGN, 0, -1);
+        signal(SIGALRM, SIG_IGN);
+        signal(SIGVTALRM, SIG_IGN);
 }
 
 void switch_timers(int to_real)