Re: [PATCH][RESEND] usb: gadget: ffs: ffs_aio_cancel(): Save/restore IRQ flags

[MichaÅ Nazarewicz]

On Thu, 16 Jan 2020 at 13:27, Alexandru Ardelean
<alexandru.ardelean@xxxxxxxxxx> wrote:
>
> From: Lars-Peter Clausen <lars@xxxxxxxxxx>
>
> ffs_aio_cancel() can be called from both interrupt and thread context. Make
> sure that the current IRQ state is saved and restored by using
> spin_{un,}lock_irq{save,restore}().
>
> Otherwise undefined behavior might occur.
>
> Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>

Acked-by: Michal Nazarewicz <mina86@xxxxxxxxxx>

> ---
>  drivers/usb/gadget/function/f_fs.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index 6f8b67e61771..bdac92d3a8d0 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -1162,18 +1162,19 @@ static int ffs_aio_cancel(struct kiocb *kiocb)
>  {
>         struct ffs_io_data *io_data = kiocb->private;
>         struct ffs_epfile *epfile = kiocb->ki_filp->private_data;
> +       unsigned long flags;
>         int value;
>
>         ENTER();
>
> -       spin_lock_irq(&epfile->ffs->eps_lock);
> +       spin_lock_irqsave(&epfile->ffs->eps_lock, flags);
>
>         if (likely(io_data && io_data->ep && io_data->req))
>                 value = usb_ep_dequeue(io_data->ep, io_data->req);
>         else
>                 value = -EINVAL;
>
> -       spin_unlock_irq(&epfile->ffs->eps_lock);
> +       spin_unlock_irqrestore(&epfile->ffs->eps_lock, flags);
>
>         return value;
>  }
> --
> 2.20.1
>


-- 
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