lkml.org 
[lkml]   [2018]   [Sep]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH AUTOSEL 4.9 01/43] usb: usbtest: use irqsave() in USB's complete callback
    Date
    From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

    [ Upstream commit 6f3fde684d0232e66ada3410f016a58e09a87689 ]

    The USB completion callback does not disable interrupts while acquiring
    the lock. We want to remove the local_irq_disable() invocation from
    __usb_hcd_giveback_urb() and therefore it is required for the callback
    handler to disable the interrupts while acquiring the lock.
    The callback may be invoked either in IRQ or BH context depending on the
    USB host controller.
    Use the _irqsave() variant of the locking primitives.

    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Acked-by: Alan Stern <stern@rowland.harvard.edu>
    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
    ---
    drivers/usb/misc/usbtest.c | 10 ++++++----
    1 file changed, 6 insertions(+), 4 deletions(-)

    diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
    index e31f72b3a22c..cc1dad83ec1d 100644
    --- a/drivers/usb/misc/usbtest.c
    +++ b/drivers/usb/misc/usbtest.c
    @@ -1080,11 +1080,12 @@ static void ctrl_complete(struct urb *urb)
    struct usb_ctrlrequest *reqp;
    struct subcase *subcase;
    int status = urb->status;
    + unsigned long flags;

    reqp = (struct usb_ctrlrequest *)urb->setup_packet;
    subcase = container_of(reqp, struct subcase, setup);

    - spin_lock(&ctx->lock);
    + spin_lock_irqsave(&ctx->lock, flags);
    ctx->count--;
    ctx->pending--;

    @@ -1183,7 +1184,7 @@ static void ctrl_complete(struct urb *urb)
    /* signal completion when nothing's queued */
    if (ctx->pending == 0)
    complete(&ctx->complete);
    - spin_unlock(&ctx->lock);
    + spin_unlock_irqrestore(&ctx->lock, flags);
    }

    static int
    @@ -1859,8 +1860,9 @@ struct transfer_context {
    static void complicated_callback(struct urb *urb)
    {
    struct transfer_context *ctx = urb->context;
    + unsigned long flags;

    - spin_lock(&ctx->lock);
    + spin_lock_irqsave(&ctx->lock, flags);
    ctx->count--;

    ctx->packet_count += urb->number_of_packets;
    @@ -1900,7 +1902,7 @@ static void complicated_callback(struct urb *urb)
    complete(&ctx->done);
    }
    done:
    - spin_unlock(&ctx->lock);
    + spin_unlock_irqrestore(&ctx->lock, flags);
    }

    static struct urb *iso_alloc_urb(
    --
    2.17.1
    \
     
     \ /
      Last update: 2018-09-07 02:48    [W:4.422 / U:0.020 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site