diff options
| author | Jerome Brunet <jbrunet@baylibre.com> | 2020-10-19 19:07:02 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-28 13:20:21 +0100 |
| commit | 38203b8385bf6283537162bde7d499f830964711 (patch) | |
| tree | a186fcc177e11d6f2da90355d5ffb97daeb5c739 /drivers/usb/class/cdc-acm.h | |
| parent | usb: host: fsl-mph-dr-of: check return of dma_set_mask() (diff) | |
| download | linux-38203b8385bf6283537162bde7d499f830964711.tar.xz linux-38203b8385bf6283537162bde7d499f830964711.zip | |
usb: cdc-acm: fix cooldown mechanism
Commit a4e7279cd1d1 ("cdc-acm: introduce a cool down") is causing
regression if there is some USB error, such as -EPROTO.
This has been reported on some samples of the Odroid-N2 using the Combee II
Zibgee USB dongle.
> struct acm *acm = container_of(work, struct acm, work)
is incorrect in case of a delayed work and causes warnings, usually from
the workqueue:
> WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:1474 __queue_work+0x480/0x528.
When this happens, USB eventually stops working completely after a while.
Also the ACM_ERROR_DELAY bit is never set, so the cooldown mechanism
previously introduced cannot be triggered and acm_submit_read_urb() is
never called.
This changes makes the cdc-acm driver use a single delayed work, fixing the
pointer arithmetic in acm_softint() and set the ACM_ERROR_DELAY when the
cooldown mechanism appear to be needed.
Fixes: a4e7279cd1d1 ("cdc-acm: introduce a cool down")
Cc: Oliver Neukum <oneukum@suse.com>
Reported-by: Pascal Vizeli <pascal.vizeli@nabucasa.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20201019170702.150534-1-jbrunet@baylibre.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/class/cdc-acm.h')
| -rw-r--r-- | drivers/usb/class/cdc-acm.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index 9dce179d031b..8aef5eb769a0 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -112,8 +112,7 @@ struct acm { # define ACM_ERROR_DELAY 3 unsigned long urbs_in_error_delay; /* these need to be restarted after a delay */ struct usb_cdc_line_coding line; /* bits, stop, parity */ - struct work_struct work; /* work queue entry for various purposes*/ - struct delayed_work dwork; /* for cool downs needed in error recovery */ + struct delayed_work dwork; /* work queue entry for various purposes */ unsigned int ctrlin; /* input control lines (DCD, DSR, RI, break, overruns) */ unsigned int ctrlout; /* output control lines (DTR, RTS) */ struct async_icount iocount; /* counters for control line changes */ |