firmware: arm_scmi: Fix requested device removal race

Browse source

scmi_protocol_device_unrequest() drops scmi_requested_devices_mtx while
notifying listeners but continues to retain the per-protocol list head.
When two SCMI drivers for the same protocol unregister concurrently, one
thread can remove the final request and free the list head while the other
is running its notifier. The latter then dereferences the freed list head
after reacquiring the mutex and can free it a second time.

Complete the list and IDR updates, including freeing an empty list head,
before dropping the mutex. Keep the blocking notifier outside the critical
section and retain only the detached request across the callback.

Fixes: d3cd7c525f ("firmware: arm_scmi: Refactor protocol device creation")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://patch.msgid.link/20260722095250.2011630-1-sudeep.holla@kernel.org
Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>

...

This commit is contained in:

Sudeep Holla 2026-07-22 10:52:50 +01:00

parent a14dd8fe0a

commit 2c4097e6c4

1 changed files with 13 additions and 13 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

26

drivers/firmware/arm_scmi/bus.c

View file