diff options
| author | Peter Wu <lekensteyn@gmail.com> | 2013-08-20 00:32:14 +0200 |
|---|---|---|
| committer | Peter Wu <lekensteyn@gmail.com> | 2013-08-20 00:32:14 +0200 |
| commit | 77cf8f5c28d302ceb0ab64bd0af9cab1ad85fac2 (patch) | |
| tree | 1506f4fa4e3150dce60b8af8a2111d802b2c729a | |
| parent | 94fc5d9de5bd757ad46f0d94bc4ebf617c4487f6 (diff) | |
| download | linux-blockdev.tar.gz | |
writeback: fix NULL dereference when device is goneblockdev
This solves a BUG followed by a lockup in the following case:
1. Connect device and look in dmesg for the address:
[ 40.034520] usb 6-2: Product: My Passport 0748
2. Write something:
dd if=/dev/zero of=/dev/sdd bs=1M
3. Remove device:
echo 1 > /sys/bus/usb/devices/6-2/remove
4. Machine locks up (because the work queue got stuck?).
Signed-off-by: Peter Wu <lekensteyn@gmail.com>
| -rw-r--r-- | fs/fs-writeback.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 68851ff2fd41..6e38a8b50b9a 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1007,7 +1007,8 @@ void bdi_writeback_workfn(struct work_struct *work) struct backing_dev_info *bdi = wb->bdi; long pages_written; - set_worker_desc("flush-%s", dev_name(bdi->dev)); + if (bdi->dev) + set_worker_desc("flush-%s", dev_name(bdi->dev)); current->flags |= PF_SWAPWRITE; if (likely(!current_is_workqueue_rescuer() || |