From 7249493949314557a5d22f52315713e5f9013e15 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 2 Jun 2020 23:46:48 +1000 Subject: jobs: Fix waitcmd busy loop We need to clear gotsigchld in waitproc because it is used as a loop conditional for the waitcmd case. Without it waitcmd may busy loop after a SIGCHLD. This patch also changes gotsigchld into a volatile sig_atomic_t to prevent compilers from optimising its accesses away. Fixes: 6c691b3e5099 ("jobs: Only clear gotsigchld when waiting...") Signed-off-by: Herbert Xu --- src/jobs.c | 2 +- src/trap.c | 2 +- src/trap.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/src/jobs.c b/src/jobs.c index 0926360..d4c13c0 100644 --- a/src/jobs.c +++ b/src/jobs.c @@ -1136,7 +1136,6 @@ static int dowait(int block, struct job *jp) rpid = 1; do { - gotsigchld = 0; pid = waitone(block, jp); rpid &= !!pid; @@ -1176,6 +1175,7 @@ waitproc(int block, int *status) #endif do { + gotsigchld = 0; do err = wait3(status, flags, NULL); while (err < 0 && errno == EINTR); diff --git a/src/trap.c b/src/trap.c index 82e7ece..cd84814 100644 --- a/src/trap.c +++ b/src/trap.c @@ -76,7 +76,7 @@ static char gotsig[NSIG - 1]; /* last pending signal */ volatile sig_atomic_t pending_sig; /* received SIGCHLD */ -int gotsigchld; +volatile sig_atomic_t gotsigchld; extern char *signal_names[]; diff --git a/src/trap.h b/src/trap.h index 4c455a8..beaf660 100644 --- a/src/trap.h +++ b/src/trap.h @@ -39,7 +39,7 @@ extern int trapcnt; extern char sigmode[]; extern volatile sig_atomic_t pending_sig; -extern int gotsigchld; +extern volatile sig_atomic_t gotsigchld; int trapcmd(int, char **); void setsignal(int); -- cgit 1.4.1