From 89b9ba661bd2d6155308f895ec075d813f0e129b Mon Sep 17 00:00:00 2001 From: Alexandre Raymond Date: Wed, 15 Jun 2011 01:20:31 -0400 Subject: [PATCH] Fix signal handling of SIG_IPI when io-thread is enabled Both the signal thread (via sigwait()) and the cpu thread (via a normal signal handler) were attempting to catch SIG_IPI. This resulted in random freezes under Darwin. This patch separates SIG_IPI from the rest of the signals handled by the signal thread, because it is independently caught by the cpu thread. Signed-off-by: Alexandre Raymond Acked-by: Jan Kiszka Signed-off-by: Blue Swirl --- cpus.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/cpus.c b/cpus.c index e02576c..3035314 100644 --- a/cpus.c +++ b/cpus.c @@ -396,10 +396,18 @@ static int qemu_signal_init(void) sigaddset(&set, SIGUSR2); pthread_sigmask(SIG_UNBLOCK, &set, NULL); + /* + * SIG_IPI must be blocked in the main thread and must not be caught + * by sigwait() in the signal thread. Otherwise, the cpu thread will + * not catch it reliably. + */ + sigemptyset(&set); + sigaddset(&set, SIG_IPI); + pthread_sigmask(SIG_BLOCK, &set, NULL); + sigemptyset(&set); sigaddset(&set, SIGIO); sigaddset(&set, SIGALRM); - sigaddset(&set, SIG_IPI); sigaddset(&set, SIGBUS); #else sigemptyset(&set); -- 2.7.4