Freezing process can abort when a client is waiting uninterruptibly
for a response. Add new macro wait_fatal_freezable to try to fix it.
Signed-off-by: cuilifei <cuili...@xiaomi.com>
---
fs/fuse/dev.c | 46 ++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 42 insertions(+), 4 deletions(-)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 70ea57c..5c63518 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -23,6 +23,23 @@
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
+#define wait_fatal_freezable(wq, condition, exclusive) \
+({ \
+ int __ret = 0; \
+ do { \
+ if (exclusive) \
+ ret = wait_event_interruptible_exclusive(wq, \
+ condition); \
+ else \
+ ret = wait_event_interruptible(wq, condition); \
+ if (!__ret || fatal_signal_pending(current)) \
+ break; \
+ if (!freezing(current)) \
+ continue; \
+ } while (try_to_freeze()); \
+ __ret; \
+})
+
static struct kmem_cache *fuse_req_cachep;
static struct fuse_dev *fuse_get_dev(struct file *file)
@@ -99,6 +116,19 @@ void fuse_request_free(struct fuse_req *req)
kmem_cache_free(fuse_req_cachep, req);
}
+static void block_sigs(sigset_t *oldset)
+{
+ sigset_t mask;
+
+ siginitsetinv(&mask, sigmask(SIGKILL));
+ sigprocmask(SIG_BLOCK, &mask, oldset);
+}
+
+static void restore_sigs(sigset_t *oldset)
+{
+ sigprocmask(SIG_SETMASK, oldset, NULL);
+}
+
void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
@@ -134,13 +164,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn
*fc, unsigned npages,
bool for_background)
{
struct fuse_req *req;
+ sigset_t oldset;
+ int intr;
int err;
atomic_inc(&fc->num_waiting);
if (fuse_block_alloc(fc, for_background)) {
err = -EINTR;
- if (wait_event_killable_exclusive(fc->blocked_waitq,
- !fuse_block_alloc(fc, for_background)))
+ block_sigs(&oldset);
+ intr = wait_fatal_freezable(fc->blocked_waitq,
+ !fuse_block_alloc(fc, for_background), true);
+ restore_sigs(&oldset);
+ if (intr)
goto out;
}
/* Matches smp_wmb() in fuse_set_initialized() */
@@ -427,9 +462,12 @@ static void request_wait_answer(struct fuse_conn *fc,
struct fuse_req *req)
}
if (!test_bit(FR_FORCE, &req->flags)) {
+ sigset_t oldset;
/* Only fatal signals may interrupt this */
- err = wait_event_killable(req->waitq,
- test_bit(FR_FINISHED, &req->flags));
+ block_sigs(&oldset);
+ err = wait_fatal_freezable(req->waitq,
+ test_bit(FR_FINISHED, &req->flags), false);
+ restore_sigs(&oldset);
if (!err)
return;
--
1.9.1
