Re: [PATCH] gma500: Fix a sleep-in-atomic bug in psbfb_2d_submit

From: Patrik Jakobsson
Date: Wed May 31 2017 - 05:56:54 EST


On Wed, May 31, 2017 at 10:48 AM, Jia-Ju Bai <baijiaju1990@xxxxxxx> wrote:
> The driver may sleep under a spin lock, and the function call path is:
> psbfb_2d_submit (acquire the lock by spin_lock_irqsave)
> psb_2d_wait_available
> psb_spank
> msleep --> may sleep
>
> To fix it, the "msleep" is replaced with "mdelay" in psb_spank.
>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxx>

Thanks for the patch. checkpatch complains about DOS line endings so
you might want to take a look at your editor settings. Usually we tag
the subject with drm/gma500 but don't think there's a hard rule about
that. I'll fix it up and take it through drm-misc-next.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@xxxxxxxxx>

> ---
> drivers/gpu/drm/gma500/accel_2d.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/gma500/accel_2d.c b/drivers/gpu/drm/gma500/accel_2d.c
> index c51d925..7c24c8a 100644
> --- a/drivers/gpu/drm/gma500/accel_2d.c
> +++ b/drivers/gpu/drm/gma500/accel_2d.c
> @@ -55,7 +55,7 @@ void psb_spank(struct drm_psb_private *dev_priv)
> _PSB_CS_RESET_TWOD_RESET, PSB_CR_SOFT_RESET);
> PSB_RSGX32(PSB_CR_SOFT_RESET);
>
> - msleep(1);
> + mdelay(1);
>
> PSB_WSGX32(0, PSB_CR_SOFT_RESET);
> wmb();
> @@ -64,7 +64,7 @@ void psb_spank(struct drm_psb_private *dev_priv)
> wmb();
> (void) PSB_RSGX32(PSB_CR_BIF_CTRL);
>
> - msleep(1);
> + mdelay(1);
> PSB_WSGX32(PSB_RSGX32(PSB_CR_BIF_CTRL) & ~_PSB_CB_CTRL_CLEAR_FAULT,
> PSB_CR_BIF_CTRL);
> (void) PSB_RSGX32(PSB_CR_BIF_CTRL);
> --
> 1.7.9.5
>
>