Commit 2e495516 authored by Mukesh Ojha's avatar Mukesh Ojha Committed by Bjorn Andersson
Browse files

firmware: qcom: scm: Fix __scm and waitq completion variable initialization 



It is possible qcom_scm_is_available() gives wrong indication that
if __scm is initialized while __scm->dev is not and similar issue
is also possible with __scm->waitq_comp.

Fix this appropriately by the use of release barrier and read barrier
that will make sure if __scm is initialized so, is all of its field
variable.

Fixes: d0f6fa7b ("firmware: qcom: scm: Convert SCM to platform driver")
Fixes: 6bf32599 ("firmware: qcom: scm: Add wait-queue handling logic")
Signed-off-by: default avatarMukesh Ojha <quic_mojha@quicinc.com>
Link: https://lore.kernel.org/r/1711034642-22860-4-git-send-email-quic_mojha@quicinc.com


Signed-off-by: default avatarBjorn Andersson <andersson@kernel.org>
parent 398a4c58

drivers/firmware/qcom/qcom_scm.c

+5 −5
Original line number Diff line number Diff line
@@ -1737,7 +1737,7 @@ static int qcom_scm_qseecom_init(struct qcom_scm *scm) 
 */

bool qcom_scm_is_available(void)

{

	return !!__scm;

	return !!READ_ONCE(__scm);

}

EXPORT_SYMBOL_GPL(qcom_scm_is_available);
@@ -1818,10 +1818,12 @@ static int qcom_scm_probe(struct platform_device *pdev) 
	if (!scm)

		return -ENOMEM;



	scm->dev = &pdev->dev;

	ret = qcom_scm_find_dload_address(&pdev->dev, &scm->dload_mode_addr);

	if (ret < 0)

		return ret;



	init_completion(&scm->waitq_comp);

	mutex_init(&scm->scm_bw_lock);



	scm->path = devm_of_icc_get(&pdev->dev, NULL);
@@ -1853,10 +1855,8 @@ static int qcom_scm_probe(struct platform_device *pdev) 
	if (ret)

		return ret;



	__scm = scm;

	__scm->dev = &pdev->dev;



	init_completion(&__scm->waitq_comp);

	/* Let all above stores be available after this */

	smp_store_release(&__scm, scm);



	irq = platform_get_irq_optional(pdev, 0);

	if (irq < 0) {