Re: [PATCH] platform/x86: dell_rbu: fix lock imbalance in img_update_realloc

[Andy Shevchenko]

On Wed, Feb 13, 2019 at 5:56 AM Stuart Hayes <stuart.w.hayes@xxxxxxxxx> wrote:
>
>
>
> On 2/11/2019 7:09 AM, Christoph Hellwig wrote:
> > We need to ensure rbu_data.lock is always held on return.
> >

Pushed to my review and testing queue, thanks!

> > Fixes: 289790a3ea94 ("platform/x86: dell_rbu: stop abusing the DMA API")
> > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> > ---
> >  drivers/platform/x86/dell_rbu.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/platform/x86/dell_rbu.c b/drivers/platform/x86/dell_rbu.c
> > index 8104ca0c44ca..031c68903583 100644
> > --- a/drivers/platform/x86/dell_rbu.c
> > +++ b/drivers/platform/x86/dell_rbu.c
> > @@ -436,6 +436,7 @@ static int img_update_realloc(unsigned long size)
> >       ordernum = get_order(size);
> >       image_update_buffer =
> >               (unsigned char *)__get_free_pages(GFP_DMA32, ordernum);
> > +     spin_lock(&rbu_data.lock);
> >       if (!image_update_buffer) {
> >               pr_debug("Not enough memory for image update:"
> >                       "size = %ld\n", size);
> > @@ -446,7 +447,6 @@ static int img_update_realloc(unsigned long size)
> >       if (WARN_ON_ONCE(img_buf_phys_addr > BIOS_SCAN_LIMIT))
> >               return -EINVAL; /* can't happen per definition */
> >
> > -     spin_lock(&rbu_data.lock);
> >       rbu_data.image_update_buffer = image_update_buffer;
> >       rbu_data.image_update_buffer_size = size;
> >       rbu_data.bios_image_size = rbu_data.image_update_buffer_size;
> >
>
> Acked-by: Stuart Hayes <stuart.w.hayes@xxxxxxxxx>



-- 
With Best Regards,
Andy Shevchenko