[PATCH] wireless: ath10k: Return early in ath10k_qmi_event_server_exit() to avoid hard crash on reboot

From: John Stultz
Date: Tue Jun 02 2020 - 01:25:42 EST


Ever since 5.7-rc1, if we call
ath10k_qmi_remove_msa_permission(), the db845c hard crashes on
reboot, resulting in the device getting stuck in the usb crash
debug mode and not coming back up wihthout a hard power off.

This hack avoids the issue by returning early in
ath10k_qmi_event_server_exit().

A better solution is very much desired!

Feedback and suggestions welcome!

Cc: Rakesh Pillai <pillair@xxxxxxxxxxxxxxxx>
Cc: Govind Singh <govinds@xxxxxxxxxxxxxx>
Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Cc: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Cc: Amit Pundir <amit.pundir@xxxxxxxxxx>
Cc: Brian Norris <briannorris@xxxxxxxxxxxx>
Cc: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Cc: ath10k@xxxxxxxxxxxxxxxxxxx
Reported-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
drivers/net/wireless/ath/ath10k/qmi.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/qmi.c b/drivers/net/wireless/ath/ath10k/qmi.c
index 85dce43c5439..ab38562ce1cb 100644
--- a/drivers/net/wireless/ath/ath10k/qmi.c
+++ b/drivers/net/wireless/ath/ath10k/qmi.c
@@ -854,6 +854,11 @@ static void ath10k_qmi_event_server_exit(struct ath10k_qmi *qmi)
struct ath10k *ar = qmi->ar;
struct ath10k_snoc *ar_snoc = ath10k_snoc_priv(ar);

+ /*
+ * HACK: Calling ath10k_qmi_remove_msa_permission causes
+ * hardware to hard crash on reboot
+ */
+ return;
ath10k_qmi_remove_msa_permission(qmi);
ath10k_core_free_board_files(ar);
if (!test_bit(ATH10K_SNOC_FLAG_UNREGISTERING, &ar_snoc->flags))
--
2.17.1