[PATCH v1 05/10] bus: mhi: core: Disable IRQs when powering down

From: Bhaumik Bhatt
Date: Fri Sep 18 2020 - 22:02:52 EST

While powering down, the device may or may not acknowledge the MHI
RESET issued by host for graceful shutdown scenario which can lead
to a rogue device sending an interrupt after the clean-up has been
done. This can result in a tasklet being scheduled after it has
been killed and access already freed memory causing a NULL pointer
exception. Avoid this corner case by disabling the interrupts as a
part of host clean up.

Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
drivers/bus/mhi/core/pm.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 1862960..3462d82 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -517,6 +517,7 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
if (mhi_event->offload_ev)
+ disable_irq(mhi_cntrl->irq[mhi_event->irq]);

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