diff options
| author | Davidlohr Bueso <dave@stgolabs.net> | 2018-08-21 21:56:45 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-22 10:52:47 -0700 |
| commit | 92e641784055998879942d39c74d4f84fa750968 (patch) | |
| tree | 590e88eb19ef4597e2e4a6ad36d18ada7ce166e5 | |
| parent | 304b18b8d6af796c8ece221d34c92aeb1559789b (diff) | |
| download | linux-92e641784055998879942d39c74d4f84fa750968.tar.bz2 | |
s/epoll: robustify irq safety with lockdep_assert_irqs_enabled()
Sprinkle lockdep_assert_irqs_enabled() checks in the functions that do not
save and restore interrupts when dealing with the ep->wq.lock. These are
ep_scan_ready_list() and those called by epoll_ctl(): ep_insert, ep_modify
and ep_remove.
[akpm@linux-foundation.org: remove too-obvious comments]
Link: http://lkml.kernel.org/r/20180721183127.3busfa335zlcjeox@linux-r8p5
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/eventpoll.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 1b1abc461fc0..58b96d8a898a 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -670,6 +670,8 @@ static __poll_t ep_scan_ready_list(struct eventpoll *ep, struct epitem *epi, *nepi; LIST_HEAD(txlist); + lockdep_assert_irqs_enabled(); + /* * We need to lock this because we could be hit by * eventpoll_release_file() and epoll_ctl(). @@ -764,6 +766,8 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi) { struct file *file = epi->ffd.file; + lockdep_assert_irqs_enabled(); + /* * Removes poll wait queue hooks. */ @@ -1412,6 +1416,8 @@ static int ep_insert(struct eventpoll *ep, const struct epoll_event *event, struct epitem *epi; struct ep_pqueue epq; + lockdep_assert_irqs_enabled(); + user_watches = atomic_long_read(&ep->user->epoll_watches); if (unlikely(user_watches >= max_user_watches)) return -ENOSPC; @@ -1540,6 +1546,8 @@ static int ep_modify(struct eventpoll *ep, struct epitem *epi, int pwake = 0; poll_table pt; + lockdep_assert_irqs_enabled(); + init_poll_funcptr(&pt, NULL); /* |