From 34a89d26bdc4ba46a406fa3842239e921c493d44 Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Thu, 28 Oct 2010 15:03:30 -0400 Subject: [PATCH] arch/tile: correct double syscall restart for nested signals This change is modelled on similar fixes for other architectures. The pt_regs "faultnum" member is set to the trap (fault) number that caused us to enter the kernel, and is INT_SWINT_1 for the syscall software interrupt. We already supported a pseudo value, INT_SWINT_1_SIGRETURN, that we used for the rt_sigreturn syscall; it avoided the case where one signal was handled, then we "tail-called" to another handler. This change avoids the similar case where we start to call one handler, then are preempted into another handler when we start trying to run the first handler. We clear ->faultnum after calling handle_signal(), and to be paranoid also in the case where there was no signal to deliver. Signed-off-by: Chris Metcalf --- arch/tile/kernel/signal.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/tile/kernel/signal.c b/arch/tile/kernel/signal.c index fb28e85ae3ae..704ce0bce833 100644 --- a/arch/tile/kernel/signal.c +++ b/arch/tile/kernel/signal.c @@ -330,7 +330,7 @@ void do_signal(struct pt_regs *regs) current_thread_info()->status &= ~TS_RESTORE_SIGMASK; } - return; + goto done; } /* Did we come from a system call? */ @@ -358,4 +358,8 @@ void do_signal(struct pt_regs *regs) current_thread_info()->status &= ~TS_RESTORE_SIGMASK; sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); } + +done: + /* Avoid double syscall restart if there are nested signals. */ + regs->faultnum = INT_SWINT_1_SIGRETURN; } -- 2.11.4.GIT