diff options
| author | Oliver Neukum <oneukum@suse.com> | 2020-04-15 17:13:57 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-16 14:59:49 +0200 |
| commit | 0afccd7601514c4b83d8cc58c740089cc447051d (patch) | |
| tree | c30222401442d5626449f2fb8e4cf32eb6b90ceb /drivers | |
| parent | UAS: fix deadlock in error handling and PM flushing work (diff) | |
| download | linux-0afccd7601514c4b83d8cc58c740089cc447051d.tar.xz linux-0afccd7601514c4b83d8cc58c740089cc447051d.zip | |
cdc-acm: close race betrween suspend() and acm_softint
Suspend increments a counter, then kills the URBs,
then kills the scheduled work. The scheduled work, however,
may reschedule the URBs. Fix this by having the work
check the counter.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Tested-by: Jonas Karlsson <jonas.karlsson@actia.se>
Link: https://lore.kernel.org/r/20200415151358.32664-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 84d6f7df09a4..4ef68e6671aa 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -557,14 +557,14 @@ static void acm_softint(struct work_struct *work) struct acm *acm = container_of(work, struct acm, work); if (test_bit(EVENT_RX_STALL, &acm->flags)) { - if (!(usb_autopm_get_interface(acm->data))) { + smp_mb(); /* against acm_suspend() */ + if (!acm->susp_count) { for (i = 0; i < acm->rx_buflimit; i++) usb_kill_urb(acm->read_urbs[i]); usb_clear_halt(acm->dev, acm->in); acm_submit_read_urbs(acm, GFP_KERNEL); - usb_autopm_put_interface(acm->data); + clear_bit(EVENT_RX_STALL, &acm->flags); } - clear_bit(EVENT_RX_STALL, &acm->flags); } if (test_and_clear_bit(EVENT_TTY_WAKEUP, &acm->flags)) |