This is a note to let you know that I've just added the patch titled drm/lima: fix shared irq handling on driver remove to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-lima-fix-shared-irq-handling-on-driver-remove.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 4506592b1966308989b380ed0094490ea2559498 Author: Erico Nunes <nunes.erico@xxxxxxxxx> Date: Tue Apr 2 00:43:28 2024 +0200 drm/lima: fix shared irq handling on driver remove [ Upstream commit a6683c690bbfd1f371510cb051e8fa49507f3f5e ] lima uses a shared interrupt, so the interrupt handlers must be prepared to be called at any time. At driver removal time, the clocks are disabled early and the interrupts stay registered until the very end of the remove process due to the devm usage. This is potentially a bug as the interrupts access device registers which assumes clocks are enabled. A crash can be triggered by removing the driver in a kernel with CONFIG_DEBUG_SHIRQ enabled. This patch frees the interrupts at each lima device finishing callback so that the handlers are already unregistered by the time we fully disable clocks. Signed-off-by: Erico Nunes <nunes.erico@xxxxxxxxx> Signed-off-by: Qiang Yu <yuq825@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20240401224329.1228468-2-nunes.erico@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/lima/lima_gp.c b/drivers/gpu/drm/lima/lima_gp.c index ccf49faedebf8..3fca560087c97 100644 --- a/drivers/gpu/drm/lima/lima_gp.c +++ b/drivers/gpu/drm/lima/lima_gp.c @@ -244,7 +244,9 @@ int lima_gp_init(struct lima_ip *ip) void lima_gp_fini(struct lima_ip *ip) { + struct lima_device *dev = ip->dev; + devm_free_irq(dev->dev, ip->irq, ip); } int lima_gp_pipe_init(struct lima_device *dev) diff --git a/drivers/gpu/drm/lima/lima_mmu.c b/drivers/gpu/drm/lima/lima_mmu.c index 8e1651d6a61fa..04e6090cce595 100644 --- a/drivers/gpu/drm/lima/lima_mmu.c +++ b/drivers/gpu/drm/lima/lima_mmu.c @@ -97,7 +97,12 @@ int lima_mmu_init(struct lima_ip *ip) void lima_mmu_fini(struct lima_ip *ip) { + struct lima_device *dev = ip->dev; + + if (ip->id == lima_ip_ppmmu_bcast) + return; + devm_free_irq(dev->dev, ip->irq, ip); } void lima_mmu_switch_vm(struct lima_ip *ip, struct lima_vm *vm) diff --git a/drivers/gpu/drm/lima/lima_pp.c b/drivers/gpu/drm/lima/lima_pp.c index 8fef224b93c85..1dacca8bffe1a 100644 --- a/drivers/gpu/drm/lima/lima_pp.c +++ b/drivers/gpu/drm/lima/lima_pp.c @@ -251,7 +251,9 @@ int lima_pp_init(struct lima_ip *ip) void lima_pp_fini(struct lima_ip *ip) { + struct lima_device *dev = ip->dev; + devm_free_irq(dev->dev, ip->irq, ip); } int lima_pp_bcast_init(struct lima_ip *ip) @@ -272,7 +274,9 @@ int lima_pp_bcast_init(struct lima_ip *ip) void lima_pp_bcast_fini(struct lima_ip *ip) { + struct lima_device *dev = ip->dev; + devm_free_irq(dev->dev, ip->irq, ip); } static int lima_pp_task_validate(struct lima_sched_pipe *pipe,