[PATCH] wifi: ath12k: fix soft lockup on suspend

[PATCH] wifi: ath12k: fix soft lockup on suspend

[Johan Hovold]

The ext interrupts are enabled when the firmware has been started, but
this may never happen, for example, if the board configuration file is
missing.

When the system is later suspended, the driver unconditionally tries to
disable interrupts, which results in an irq disable imbalance and causes
the driver to spin indefinitely in napi_synchronize().

Make sure that the interrupts have been enabled before attempting to
disable them.

Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Cc: stable@vger.kernel.org	# 6.3
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/net/wireless/ath/ath12k/pci.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath12k/pci.c b/drivers/net/wireless/ath/ath12k/pci.c
index 16af046c33d9..55fde0d33183 100644
--- a/drivers/net/wireless/ath/ath12k/pci.c
+++ b/drivers/net/wireless/ath/ath12k/pci.c
@@ -472,7 +472,8 @@ static void __ath12k_pci_ext_irq_disable(struct ath12k_base *ab)
 {
 	int i;
 
-	clear_bit(ATH12K_FLAG_EXT_IRQ_ENABLED, &ab->dev_flags);
+	if (!test_and_clear_bit(ATH12K_FLAG_EXT_IRQ_ENABLED, &ab->dev_flags))
+		return;
 
 	for (i = 0; i < ATH12K_EXT_IRQ_GRP_NUM_MAX; i++) {
 		struct ath12k_ext_irq_grp *irq_grp = &ab->ext_irq_grp[i];
-- 
2.44.1

Re: [PATCH] wifi: ath12k: fix soft lockup on suspend

[Jeff Johnson]

On 7/9/2024 12:31 AM, Johan Hovold wrote:
> The ext interrupts are enabled when the firmware has been started, but
> this may never happen, for example, if the board configuration file is
> missing.
> 
> When the system is later suspended, the driver unconditionally tries to
> disable interrupts, which results in an irq disable imbalance and causes
> the driver to spin indefinitely in napi_synchronize().
> 
> Make sure that the interrupts have been enabled before attempting to
> disable them.
> 
> Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
> Cc: stable@vger.kernel.org	# 6.3
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>