Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

ath11k: Fix frames flush failure caused by deadlock

We are seeing below warnings:

kernel: [25393.301506] ath11k_pci 0000:01:00.0: failed to flush mgmt transmit queue 0 kernel: [25398.421509] ath11k_pci 0000:01:00.0: failed to flush mgmt transmit queue 0 kernel: [25398.421831] ath11k_pci 0000:01:00.0: dropping mgmt frame for vdev 0, is_started 0

this means ath11k fails to flush mgmt. frames because wmi_mgmt_tx_work has no chance to run in 5 seconds.

By setting /proc/sys/kernel/hung_task_timeout_secs to 20 and increasing ATH11K_FLUSH_TIMEOUT to 50 we get below warnings:

kernel: [ 120.763160] INFO: task wpa_supplicant:924 blocked for more than 20 seconds. kernel: [ 120.763169] Not tainted 5.10.90 #12 kernel: [ 120.763177] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kernel: [ 120.763186] task:wpa_supplicant state:D stack: 0 pid: 924 ppid: 1 flags:0x000043a0 kernel: [ 120.763201] Call Trace: kernel: [ 120.763214] __schedule+0x785/0x12fa kernel: [ 120.763224] ? lockdep_hardirqs_on_prepare+0xe2/0x1bb kernel: [ 120.763242] schedule+0x7e/0xa1 kernel: [ 120.763253] schedule_timeout+0x98/0xfe kernel: [ 120.763266] ? run_local_timers+0x4a/0x4a kernel: [ 120.763291] ath11k_mac_flush_tx_complete+0x197/0x2b1 [ath11k 13c3a9bf37790f4ac8103b3decf7ab4008ac314a] kernel: [ 120.763306] ? init_wait_entry+0x2e/0x2e kernel: [ 120.763343] __ieee80211_flush_queues…