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authorThomas Zimmermann <tzimmermann@suse.de>2024-02-07 13:01:19 +0100
committerThomas Zimmermann <tzimmermann@suse.de>2024-02-07 13:02:20 +0100
commit0e85f1ae4ac6dae238b0f35232d1aa52e1b6943f (patch)
tree75b387bc359637c15b90ababb1ff073ca68b5bd8 /drivers/firmware/arm_scmi/mailbox.c
parent2c8ba564a42c7418a726367c73d7c88454848fdc (diff)
parentf8e4806e0dfa8796b3d7076a7fe054455a59c38b (diff)
Merge drm/drm-next into drm-misc-next
Backmerging to update drm-misc-next to the state of v6.8-rc3. Also fixes a build problem with xe. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Diffstat (limited to 'drivers/firmware/arm_scmi/mailbox.c')
-rw-r--r--drivers/firmware/arm_scmi/mailbox.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 19246ed1f01f..b8d470417e8f 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -45,6 +45,20 @@ static void rx_callback(struct mbox_client *cl, void *m)
{
struct scmi_mailbox *smbox = client_to_scmi_mailbox(cl);
+ /*
+ * An A2P IRQ is NOT valid when received while the platform still has
+ * the ownership of the channel, because the platform at first releases
+ * the SMT channel and then sends the completion interrupt.
+ *
+ * This addresses a possible race condition in which a spurious IRQ from
+ * a previous timed-out reply which arrived late could be wrongly
+ * associated with the next pending transaction.
+ */
+ if (cl->knows_txdone && !shmem_channel_free(smbox->shmem)) {
+ dev_warn(smbox->cinfo->dev, "Ignoring spurious A2P IRQ !\n");
+ return;
+ }
+
scmi_rx_callback(smbox->cinfo, shmem_read_header(smbox->shmem), NULL);
}