Re: [PATCH 10/11] drm/panthor: Interrupt group start/resumption if group_bind_locked() fails

[Liviu Dudau <liviu.dudau@arm.com>]

On Thu, Jun 25, 2026 at 02:40:36PM +0200, Boris Brezillon wrote:
> group_bind_locked() can fail if the MMU block is stuck. This is normally
> a reset situation, but by the time we reset the GPU, we might have
> tried to resume a group that's not resident, which will probably trip
> out the FW. So let's avoid that by bailing out when group_bind_locked()
> returns an error. We don't even try to start more groups because the
> GPU will be reset anyway.
> 
> Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
> Reported-by: sashiko-bot@kernel.org
> Closes: https://sashiko.dev/#/patchset/20260623-panthor-signal-from-irq-v3-0-2ece396f8ee0@collabora.com?part=7
> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>

Best regards,
Liviu

> ---
>  drivers/gpu/drm/panthor/panthor_sched.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> index 5fe95d03f23e..298b046c95ed 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -2368,7 +2368,13 @@ tick_ctx_apply(struct panthor_scheduler *sched, struct panthor_sched_tick_ctx *c
>  
>  			csg_iface = panthor_fw_get_csg_iface(ptdev, csg_id);
>  			csg_slot = &sched->csg_slots[csg_id];
> -			group_bind_locked(group, csg_id);
> +			ret = group_bind_locked(group, csg_id);
> +			if (ret) {
> +				panthor_device_schedule_reset(ptdev);
> +				ctx->csg_upd_failed_mask |= BIT(csg_id);
> +				return;
> +			}
> +
>  			csg_slot_prog_locked(ptdev, csg_id, new_csg_prio--);
>  			csgs_upd_ctx_queue_reqs(ptdev, &upd_ctx, csg_id,
>  						group->state == PANTHOR_CS_GROUP_SUSPENDED ?
> 
> -- 
> 2.54.0
> 

-- 
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