diff options
| author | Baochen Qiang <quic_bqiang@quicinc.com> | 2023-11-17 08:39:19 +0800 |
|---|---|---|
| committer | Kalle Valo <quic_kvalo@quicinc.com> | 2023-11-30 19:04:07 +0200 |
| commit | 5082b3e3027eae393a4e86874bffb4ce3f83c26e (patch) | |
| tree | 93a7c1228d108bbc05c594170c70b5447840e6ff | |
| parent | f20eb4cb93240c4da4c7a3563b4063047bef3a7b (diff) | |
wifi: ath11k: fix race due to setting ATH11K_FLAG_EXT_IRQ_ENABLED too early
We are seeing below error randomly in the case where only
one MSI vector is configured:
kernel: ath11k_pci 0000:03:00.0: wmi command 16387 timeout
The reason is, currently, in ath11k_pcic_ext_irq_enable(),
ATH11K_FLAG_EXT_IRQ_ENABLED is set before NAPI is enabled.
This results in a race condition: after
ATH11K_FLAG_EXT_IRQ_ENABLED is set but before NAPI enabled,
CE interrupt breaks in. Since IRQ is shared by CE and data
path, ath11k_pcic_ext_interrupt_handler() is also called
where we call disable_irq_nosync() to disable IRQ. Then
napi_schedule() is called but it does nothing because NAPI
is not enabled at that time, meaning
ath11k_pcic_ext_grp_napi_poll() will never run, so we have
no chance to call enable_irq() to enable IRQ back. Finally
we get above error.
Fix it by setting ATH11K_FLAG_EXT_IRQ_ENABLED after all
NAPI and IRQ work are done. With the fix, we are sure that
by the time ATH11K_FLAG_EXT_IRQ_ENABLED is set, NAPI is
enabled.
Note that the fix above also introduce some side effects:
if ath11k_pcic_ext_interrupt_handler() breaks in after NAPI
enabled but before ATH11K_FLAG_EXT_IRQ_ENABLED set, nothing
will be done by the handler this time, the work will be
postponed till the next time the IRQ fires.
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20231117003919.26218-1-quic_bqiang@quicinc.com
| -rw-r--r-- | drivers/net/wireless/ath/ath11k/pcic.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/net/wireless/ath/ath11k/pcic.c b/drivers/net/wireless/ath/ath11k/pcic.c index 90d8936a3e2e..15e2ceb22a44 100644 --- a/drivers/net/wireless/ath/ath11k/pcic.c +++ b/drivers/net/wireless/ath/ath11k/pcic.c @@ -460,8 +460,6 @@ void ath11k_pcic_ext_irq_enable(struct ath11k_base *ab) { int i; - set_bit(ATH11K_FLAG_EXT_IRQ_ENABLED, &ab->dev_flags); - for (i = 0; i < ATH11K_EXT_IRQ_GRP_NUM_MAX; i++) { struct ath11k_ext_irq_grp *irq_grp = &ab->ext_irq_grp[i]; @@ -471,6 +469,8 @@ void ath11k_pcic_ext_irq_enable(struct ath11k_base *ab) } ath11k_pcic_ext_grp_enable(irq_grp); } + + set_bit(ATH11K_FLAG_EXT_IRQ_ENABLED, &ab->dev_flags); } EXPORT_SYMBOL(ath11k_pcic_ext_irq_enable); |