lkml.org 
[lkml]   [2020]   [Apr]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.6 144/167] cdc-acm: close race betrween suspend() and acm_softint
    Date
    From: Oliver Neukum <oneukum@suse.com>

    commit 0afccd7601514c4b83d8cc58c740089cc447051d upstream.

    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>

    ---
    drivers/usb/class/cdc-acm.c | 6 +++---
    1 file changed, 3 insertions(+), 3 deletions(-)

    --- a/drivers/usb/class/cdc-acm.c
    +++ b/drivers/usb/class/cdc-acm.c
    @@ -557,14 +557,14 @@ static void acm_softint(struct work_stru
    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))

    \
     
     \ /
      Last update: 2020-04-28 20:39    [W:4.217 / U:0.344 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site