eventfd: guard wake_up in eventfd fs calls as well
Guard wakeups that the user can trigger, and that may end up triggering a call back into eventfd_signal. This is in addition to the current approach that only guards in eventfd_signal. Rename in_eventfd_signal -> in_eventfd at the same time to reflect this. Without this there would be a deadlock in the following code using libaio: int main() { struct io_context *ctx = NULL; struct iocb iocb; struct iocb *iocbs[] = { &iocb }; int evfd; uint64_t val = 1; evfd = eventfd(0, EFD_CLOEXEC); assert(!io_setup(2, &ctx)); io_prep_poll(&iocb, evfd, POLLIN); io_set_eventfd(&iocb, evfd); assert(1 == io_submit(ctx, 1, iocbs)); write(evfd, &val, 8); } Signed-off-by:Dylan Yudaken <dylany@fb.com> Reviewed-by:
Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20220816135959.1490641-1-dylany@fb.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
parent
521a547c
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