[PATCH AUTOSEL 5.15 14/98] ath11k: pci: fix crash on suspend if board file is not found

From: Sasha Levin
Date: Fri Apr 01 2022 - 11:14:10 EST


From: Kalle Valo <quic_kvalo@xxxxxxxxxxx>

[ Upstream commit b4f4c56459a5c744f7f066b9fc2b54ea995030c5 ]

Mario reported that the kernel was crashing on suspend if ath11k was not able
to find a board file:

[ 473.693286] PM: Suspending system (s2idle)
[ 473.693291] printk: Suspending console(s) (use no_console_suspend to debug)
[ 474.407787] BUG: unable to handle page fault for address: 0000000000002070
[ 474.407791] #PF: supervisor read access in kernel mode
[ 474.407794] #PF: error_code(0x0000) - not-present page
[ 474.407798] PGD 0 P4D 0
[ 474.407801] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 474.407805] CPU: 2 PID: 2350 Comm: kworker/u32:14 Tainted: G W 5.16.0 #248
[...]
[ 474.407868] Call Trace:
[ 474.407870] <TASK>
[ 474.407874] ? _raw_spin_lock_irqsave+0x2a/0x60
[ 474.407882] ? lock_timer_base+0x72/0xa0
[ 474.407889] ? _raw_spin_unlock_irqrestore+0x29/0x3d
[ 474.407892] ? try_to_del_timer_sync+0x54/0x80
[ 474.407896] ath11k_dp_rx_pktlog_stop+0x49/0xc0 [ath11k]
[ 474.407912] ath11k_core_suspend+0x34/0x130 [ath11k]
[ 474.407923] ath11k_pci_pm_suspend+0x1b/0x50 [ath11k_pci]
[ 474.407928] pci_pm_suspend+0x7e/0x170
[ 474.407935] ? pci_pm_freeze+0xc0/0xc0
[ 474.407939] dpm_run_callback+0x4e/0x150
[ 474.407947] __device_suspend+0x148/0x4c0
[ 474.407951] async_suspend+0x20/0x90
dmesg-efi-164255130401001:
Oops#1 Part1
[ 474.407955] async_run_entry_fn+0x33/0x120
[ 474.407959] process_one_work+0x220/0x3f0
[ 474.407966] worker_thread+0x4a/0x3d0
[ 474.407971] kthread+0x17a/0x1a0
[ 474.407975] ? process_one_work+0x3f0/0x3f0
[ 474.407979] ? set_kthread_struct+0x40/0x40
[ 474.407983] ret_from_fork+0x22/0x30
[ 474.407991] </TASK>

The issue here is that board file loading happens after ath11k_pci_probe()
succesfully returns (ath11k initialisation happends asynchronously) and the
suspend handler is still enabled, of course failing as ath11k is not properly
initialised. Fix this by checking ATH11K_FLAG_QMI_FAIL during both suspend and
resume.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03003-QCAHSPSWPL_V1_V2_SILICONZ_LITE-2

Reported-by: Mario Limonciello <mario.limonciello@xxxxxxx>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215504
Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220127090117.2024-1-kvalo@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/ath/ath11k/pci.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/net/wireless/ath/ath11k/pci.c b/drivers/net/wireless/ath/ath11k/pci.c
index 54ce08f1c6e0..353a2d669fcd 100644
--- a/drivers/net/wireless/ath/ath11k/pci.c
+++ b/drivers/net/wireless/ath/ath11k/pci.c
@@ -1382,6 +1382,11 @@ static __maybe_unused int ath11k_pci_pm_suspend(struct device *dev)
struct ath11k_base *ab = dev_get_drvdata(dev);
int ret;

+ if (test_bit(ATH11K_FLAG_QMI_FAIL, &ab->dev_flags)) {
+ ath11k_dbg(ab, ATH11K_DBG_BOOT, "boot skipping pci suspend as qmi is not initialised\n");
+ return 0;
+ }
+
ret = ath11k_core_suspend(ab);
if (ret)
ath11k_warn(ab, "failed to suspend core: %d\n", ret);
@@ -1394,6 +1399,11 @@ static __maybe_unused int ath11k_pci_pm_resume(struct device *dev)
struct ath11k_base *ab = dev_get_drvdata(dev);
int ret;

+ if (test_bit(ATH11K_FLAG_QMI_FAIL, &ab->dev_flags)) {
+ ath11k_dbg(ab, ATH11K_DBG_BOOT, "boot skipping pci resume as qmi is not initialised\n");
+ return 0;
+ }
+
ret = ath11k_core_resume(ab);
if (ret)
ath11k_warn(ab, "failed to resume core: %d\n", ret);
--
2.34.1