From 69be8f189653cd81aae5a74e26615b12871bb72e Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 29 Aug 2005 11:44:09 -0400 Subject: [PATCH] convert signal handling of NODEFER to act like other Unix boxes. It has been reported that the way Linux handles NODEFER for signals is not consistent with the way other Unix boxes handle it. I've written a program to test the behavior of how this flag affects signals and had several reports from people who ran this on various Unix boxes, confirming that Linux seems to be unique on the way this is handled. The way NODEFER affects signals on other Unix boxes is as follows: 1) If NODEFER is set, other signals in sa_mask are still blocked. 2) If NODEFER is set and the signal is in sa_mask, then the signal is still blocked. (Note: this is the behavior of all tested but Linux _and_ NetBSD 2.0 *). The way NODEFER affects signals on Linux: 1) If NODEFER is set, other signals are _not_ blocked regardless of sa_mask (Even NetBSD doesn't do this). 2) If NODEFER is set and the signal is in sa_mask, then the signal being handled is not blocked. The patch converts signal handling in all current Linux architectures to the way most Unix boxes work. Unix boxes that were tested: DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU 3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX. * NetBSD was the only other Unix to behave like Linux on point #2. The main concern was brought up by point #1 which even NetBSD isn't like Linux. So with this patch, we leave NetBSD as the lonely one that behaves differently here with #2. Signed-off-by: Linus Torvalds --- arch/arm/kernel/signal.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 5e435e42dac..a94d75fef59 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -658,11 +658,12 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, /* * Block the signal if we were unsuccessful. */ - if (ret != 0 || !(ka->sa.sa_flags & SA_NODEFER)) { + if (ret != 0) { spin_lock_irq(&tsk->sighand->siglock); sigorsets(&tsk->blocked, &tsk->blocked, &ka->sa.sa_mask); - sigaddset(&tsk->blocked, sig); + if (!(ka->sa.sa_flags & SA_NODEFER)) + sigaddset(&tsk->blocked, sig); recalc_sigpending(); spin_unlock_irq(&tsk->sighand->siglock); } -- cgit v1.2.3