[PATCH] drm/imagination: Fix deadlock in soft reset sequence

From: Alessio Belle

Date: Mon Mar 09 2026 - 11:33:40 EST


The soft reset sequence is currently executed from the threaded IRQ
handler, hence it cannot call disable_irq() which internally waits
for IRQ handlers, i.e. itself, to complete.

Use disable_irq_nosync() during a soft reset instead.

Fixes: cc1aeedb98ad ("drm/imagination: Implement firmware infrastructure and META FW support")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Alessio Belle <alessio.belle@xxxxxxxxxx>
---
drivers/gpu/drm/imagination/pvr_power.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/imagination/pvr_power.c b/drivers/gpu/drm/imagination/pvr_power.c
index 7a8765c0c1ed..046cce76498a 100644
--- a/drivers/gpu/drm/imagination/pvr_power.c
+++ b/drivers/gpu/drm/imagination/pvr_power.c
@@ -510,7 +510,16 @@ pvr_power_reset(struct pvr_device *pvr_dev, bool hard_reset)
}

/* Disable IRQs for the duration of the reset. */
- disable_irq(pvr_dev->irq);
+ if (hard_reset) {
+ disable_irq(pvr_dev->irq);
+ } else {
+ /*
+ * Soft reset is triggered as a response to a FW command to the Host and is
+ * processed from the threaded IRQ handler. This code cannot (nor needs to)
+ * wait for any IRQ processing to complete.
+ */
+ disable_irq_nosync(pvr_dev->irq);
+ }

do {
if (hard_reset) {

---
base-commit: d2e20c8951e4bb5f4a828aed39813599980353b6
change-id: 20260309-fix-soft-reset-8f32c3783d3d

Best regards,
--
Alessio Belle <alessio.belle@xxxxxxxxxx>