The patch titled aio: wake all waiters when destroying ctx has been added to the -mm tree. Its filename is aio-wake-all-waiters-when-destroying-ctx.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: aio: wake all waiters when destroying ctx From: Roland Dreier <roland@xxxxxxxxxxxxxxx> The test program below will hang because io_getevents() uses add_wait_queue_exclusive(), which means the wake_up() in io_destroy() only wakes up one of the threads. Fix this by using wake_up_all() in the aio code paths where we want to make sure no one gets stuck. // t.c -- compile with gcc -lpthread -laio t.c #include <libaio.h> #include <pthread.h> #include <stdio.h> #include <unistd.h> static const int nthr = 2; void *getev(void *ctx) { struct io_event ev; io_getevents(ctx, 1, 1, &ev, NULL); printf("io_getevents returned\n"); return NULL; } int main(int argc, char *argv[]) { io_context_t ctx = 0; pthread_t thread[nthr]; int i; io_setup(1024, &ctx); for (i = 0; i < nthr; ++i) pthread_create(&thread[i], NULL, getev, ctx); sleep(1); io_destroy(ctx); for (i = 0; i < nthr; ++i) pthread_join(thread[i], NULL); return 0; } Signed-off-by: Roland Dreier <roland@xxxxxxxxxxxxxxx> Reviewed-by: Jeff Moyer <jmoyer@xxxxxxxxxx> Cc: <stable@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/aio.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff -puN fs/aio.c~aio-wake-all-waiters-when-destroying-ctx fs/aio.c --- a/fs/aio.c~aio-wake-all-waiters-when-destroying-ctx +++ a/fs/aio.c @@ -509,7 +509,7 @@ static inline void really_put_req(struct ctx->reqs_active--; if (unlikely(!ctx->reqs_active && ctx->dead)) - wake_up(&ctx->wait); + wake_up_all(&ctx->wait); } static void aio_fput_routine(struct work_struct *data) @@ -1218,7 +1218,7 @@ static void io_destroy(struct kioctx *io * by other CPUs at this point. Right now, we rely on the * locking done by the above calls to ensure this consistency. */ - wake_up(&ioctx->wait); + wake_up_all(&ioctx->wait); put_ioctx(ioctx); /* once for the lookup */ } _ Patches currently in -mm which might be from roland@xxxxxxxxxxxxxxx are linux-next.patch aio-wake-all-waiters-when-destroying-ctx.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html