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@gmail.com>
Signed-off-by: Qiang Yu <yuq825@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240401224329.1228468-2-nunes.erico@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/lima/lima_gp.c b/drivers/gpu/drm/lima/lima_gp.c
index ccf49faedebf8561627d33e8fbe5d2a0fd59e79f..3fca560087c97fc3a0c3eb99d4631ae3dcd2d511 100644 (file)
--- 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 8e1651d6a61fafacec97e67991aafd3436271311..04e6090cce595069a447660f164d780d45e9a4da 100644 (file)
--- 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 8fef224b93c8568fc70bd483739a7cd84d5e49e6..1dacca8bffe1aa7e8f8d963cf343f68957b58613 100644 (file)
--- 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,