firmware: qcom: scm: Fix NULL dereference in IRQ handler before __scm is published

In qcom_scm_probe(), devm_request_threaded_irq() is called before
smp_store_release(&__scm, scm). Two paths can dereference __scm before
it is published, both causing a NULL pointer dereference.

The IRQ handler receives scm via its data argument but passes only wq_ctx
to qcom_scm_waitq_wakeup() and qcom_scm_get_completion(), which then
dereference __scm directly. Thread scm through both functions so the IRQ
handler path never touches __scm.

Non-atomic SMC calls made during probe (e.g. from qcom_tzmem_init via
qcom_scm_shm_bridge_enable) can return WAITQ_SLEEP, causing
qcom_scm_wait_for_wq_completion() to run before __scm is published and
dereference it. Add platform_set_drvdata(pdev, scm) early in probe and
change qcom_scm_wait_for_wq_completion() to take the device pointer and
use dev_get_drvdata() to reach scm, removing any dependency on __scm.

Fixes: 6bf325992236 ("firmware: qcom: scm: Add wait-queue handling logic")
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260724094939.613844-2-mukesh.ojha@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

0 files changed, 0 insertions, 0 deletions