Ville Syrjälä wrote:
> Lockdep warns us that sc_pm_lock and cc_lock can cause a deadlock when
> cc_lock is acquired by itself with interrupts enabled. Disable irqs
> whenever taking cc_lock to avoid this.
>
> [ 19.094524] kworker/u2:0/5 just changed the state of lock:
> [ 19.094578] (&(&sc->sc_pm_lock)->rlock){-.-...}, at: [<f836c00e>]
> ath_isr+0x15e/0x200 [ath9k]
> [ 19.094674] but this lock took another, HARDIRQ-unsafe lock in the past:
> [ 19.094731] (&(&common->cc_lock)->rlock){+.-...}
> [ 19.094741]
>
> and interrupts could create inverse lock ordering between them.
>
> [ 19.094866]
> other info that might help us debug this:
> [ 19.094926] Possible interrupt unsafe locking scenario:
>
> [ 19.094985] CPU0 CPU1
> [ 19.095036] ---- ----
> [ 19.095086] lock(&(&common->cc_lock)->rlock);
> [ 19.095197] local_irq_disable();
> [ 19.095305] lock(&(&sc->sc_pm_lock)->rlock);
> [ 19.095423]
> lock(&(&common->cc_lock)->rlock);
> [ 19.095539] <Interrupt>
> [ 19.095636] lock(&(&sc->sc_pm_lock)->rlock);
> [ 19.095745]
> *** DEADLOCK ***
>
> [ 19.095965] 3 locks held by kworker/u2:0/5:
> [ 19.096067] #0: ("%s"wiphy_name(local->hw.wiphy)){.+.+.+}, at:
> [<c1067f37>] process_one_work+0x127/0x580
> [ 19.096260] #1: ((&local->dynamic_ps_enable_work)){+.+...}, at:
> [<c1067f37>] process_one_work+0x127/0x580
> [ 19.096447] #2: (&sc->mutex){+.+...}, at: [<f836b8b0>]
> ath9k_config+0x30/0x1d0 [ath9k]
> [ 19.096639]
> the shortest dependencies between 2nd lock and 1st lock:
> [ 19.096813] -> (&(&common->cc_lock)->rlock){+.-...} ops: 38 {
> [ 19.096816] HARDIRQ-ON-W at:
> [ 19.096816] __lock_acquire+0x57e/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock_bh+0x3f/0x50
> [ 19.096816] ath_chanctx_set_channel+0xb6/0x2c0
> [ath9k]
> [ 19.096816] ath9k_config+0xa8/0x1d0 [ath9k]
> [ 19.096816] ieee80211_hw_config+0xa8/0x5f0 [mac80211]
> [ 19.096816] ieee80211_do_open+0x67a/0x920 [mac80211]
> [ 19.096816] ieee80211_open+0x41/0x50 [mac80211]
> [ 19.096816] __dev_open+0xab/0x140
> [ 19.096816] __dev_change_flags+0x89/0x150
> [ 19.096816] dev_change_flags+0x28/0x60
> [ 19.096816] do_setlink+0x290/0x890
> [ 19.096816] rtnl_newlink+0x7cf/0x8e0
> [ 19.096816] rtnetlink_rcv_msg+0xbf/0x1f0
> [ 19.096816] netlink_rcv_skb+0xb9/0xe0
> [ 19.096816] rtnetlink_rcv+0x1e/0x30
> [ 19.096816] netlink_unicast+0x13a/0x2c0
> [ 19.096816] netlink_sendmsg+0x290/0x380
> [ 19.096816] ___sys_sendmsg+0x1e2/0x280
> [ 19.096816] __sys_sendmsg+0x3f/0x80
> [ 19.096816] SyS_socketcall+0x58c/0x6b0
> [ 19.096816] do_fast_syscall_32+0x96/0x1d0
> [ 19.096816] entry_SYSENTER_32+0x4c/0x7b
> [ 19.096816] IN-SOFTIRQ-W at:
> [ 19.096816] __lock_acquire+0x55a/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock+0x3c/0x50
> [ 19.096816] ath_ps_full_sleep+0x24/0x70 [ath9k]
> [ 19.096816] call_timer_fn+0xa4/0x300
> [ 19.096816] run_timer_softirq+0x1b1/0x560
> [ 19.096816] __do_softirq+0xb0/0x430
> [ 19.096816] do_softirq_own_stack+0x33/0x40
> [ 19.096816] irq_exit+0xad/0xc0
> [ 19.096816] smp_apic_timer_interrupt+0x31/0x40
> [ 19.096816] apic_timer_interrupt+0x37/0x3c
> [ 19.096816] wp_page_copy+0xb8/0x580
> [ 19.096816] do_wp_page+0x64/0x420
> [ 19.096816] handle_mm_fault+0x430/0x990
> [ 19.096816] __do_page_fault+0x18b/0x430
> [ 19.096816] do_page_fault+0xb/0x10
> [ 19.096816] common_exception+0x62/0x6a
> [ 19.096816] INITIAL USE at:
> [ 19.096816] __lock_acquire+0x204/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock_bh+0x3f/0x50
> [ 19.096816] ath_chanctx_set_channel+0xb6/0x2c0 [ath9k]
> [ 19.096816] ath9k_config+0xa8/0x1d0 [ath9k]
> [ 19.096816] ieee80211_hw_config+0xa8/0x5f0 [mac80211]
> [ 19.096816] ieee80211_do_open+0x67a/0x920 [mac80211]
> [ 19.096816] ieee80211_open+0x41/0x50 [mac80211]
> [ 19.096816] __dev_open+0xab/0x140
> [ 19.096816] __dev_change_flags+0x89/0x150
> [ 19.096816] dev_change_flags+0x28/0x60
> [ 19.096816] do_setlink+0x290/0x890
> [ 19.096816] rtnl_newlink+0x7cf/0x8e0
> [ 19.096816] rtnetlink_rcv_msg+0xbf/0x1f0
> [ 19.096816] netlink_rcv_skb+0xb9/0xe0
> [ 19.096816] rtnetlink_rcv+0x1e/0x30
> [ 19.096816] netlink_unicast+0x13a/0x2c0
> [ 19.096816] netlink_sendmsg+0x290/0x380
> [ 19.096816] ___sys_sendmsg+0x1e2/0x280
> [ 19.096816] __sys_sendmsg+0x3f/0x80
> [ 19.096816] SyS_socketcall+0x58c/0x6b0
> [ 19.096816] do_fast_syscall_32+0x96/0x1d0
> [ 19.096816] entry_SYSENTER_32+0x4c/0x7b
> [ 19.096816] }
> [ 19.096816] ... key at: [<f837b694>] __key.61991+0x0/0xffffc96c
> [ath9k]
> [ 19.096816] ... acquired at:
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock+0x3c/0x50
> [ 19.096816] ath9k_ps_wakeup+0x85/0xe0 [ath9k]
> [ 19.096816] ath9k_bss_info_changed+0x2a/0x1b0 [ath9k]
> [ 19.096816] ieee80211_bss_info_change_notify+0xf3/0x360 [mac80211]
> [ 19.096816] ieee80211_recalc_txpower+0x33/0x40 [mac80211]
> [ 19.096816] ieee80211_set_tx_power+0x45/0x1d0 [mac80211]
> [ 19.096816] cfg80211_wext_siwtxpower+0xd3/0x350 [cfg80211]
> [ 19.096816] ioctl_standard_call+0x4e/0x400
> [ 19.096816] wext_handle_ioctl+0xf4/0x190
> [ 19.096816] dev_ioctl+0xb7/0x630
> [ 19.096816] sock_ioctl+0x13e/0x2d0
> [ 19.096816] do_vfs_ioctl+0x84/0x750
> [ 19.096816] SyS_ioctl+0x34/0x60
> [ 19.096816] do_fast_syscall_32+0x96/0x1d0
> [ 19.096816] entry_SYSENTER_32+0x4c/0x7b
>
> [ 19.096816] -> (&(&sc->sc_pm_lock)->rlock){-.-...} ops: 597 {
> [ 19.096816] IN-HARDIRQ-W at:
> [ 19.096816] __lock_acquire+0x6ae/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock_irqsave+0x45/0x60
> [ 19.096816] ath_isr+0x15e/0x200 [ath9k]
> [ 19.096816] __handle_irq_event_percpu+0x44/0x340
> [ 19.096816] handle_irq_event_percpu+0x1d/0x50
> [ 19.096816] handle_irq_event+0x32/0x60
> [ 19.096816] handle_level_irq+0x81/0x100
> [ 19.096816] handle_irq+0x9c/0xd0
> [ 19.096816] do_IRQ+0x5c/0x120
> [ 19.096816] common_interrupt+0x36/0x3c
> [ 19.096816] _raw_spin_unlock_irqrestore+0x57/0x70
> [ 19.096816] ath9k_config+0x16a/0x1d0 [ath9k]
> [ 19.096816] ieee80211_hw_config+0xa8/0x5f0 [mac80211]
> [ 19.096816]
> ieee80211_dynamic_ps_enable_work+0x1c3/0x680 [mac80211]
> [ 19.096816] process_one_work+0x1d1/0x580
> [ 19.096816] worker_thread+0x31/0x380
> [ 19.096816] kthread+0xd9/0x110
> [ 19.096816] ret_from_fork+0x19/0x24
> [ 19.096816] IN-SOFTIRQ-W at:
> [ 19.096816] __lock_acquire+0x55a/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock_irqsave+0x45/0x60
> [ 19.096816] ath9k_ps_wakeup+0x24/0xe0 [ath9k]
> [ 19.096816] ath9k_tasklet+0x42/0x260 [ath9k]
> [ 19.096816] tasklet_action+0x196/0x1e0
> [ 19.096816] __do_softirq+0xb0/0x430
> [ 19.096816] do_softirq_own_stack+0x33/0x40
> [ 19.096816] irq_exit+0xad/0xc0
> [ 19.096816] do_IRQ+0x65/0x120
> [ 19.096816] common_interrupt+0x36/0x3c
> [ 19.096816] get_page_from_freelist+0x20a/0x970
> [ 19.096816] __alloc_pages_nodemask+0xca/0xed0
> [ 19.096816] __get_free_pages+0x14/0x30
> [ 19.096816] pgd_alloc+0x1d/0x160
> [ 19.096816] mm_init.isra.47+0x13a/0x1b0
> [ 19.096816] copy_process.part.54+0xb55/0x1700
> [ 19.096816] _do_fork+0xd4/0x6a0
> [ 19.096816] SyS_clone+0x27/0x30
> [ 19.096816] do_fast_syscall_32+0x96/0x1d0
> [ 19.096816] entry_SYSENTER_32+0x4c/0x7b
> [ 19.096816] INITIAL USE at:
> [ 19.096816] __lock_acquire+0x204/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock_irqsave+0x45/0x60
> [ 19.096816] ath9k_ps_wakeup+0x24/0xe0 [ath9k]
> [ 19.096816] ath9k_start+0x29/0x1f0 [ath9k]
> [ 19.096816] drv_start+0x71/0x270 [mac80211]
> [ 19.096816] ieee80211_do_open+0x31f/0x920 [mac80211]
> [ 19.096816] ieee80211_open+0x41/0x50 [mac80211]
> [ 19.096816] __dev_open+0xab/0x140
> [ 19.096816] __dev_change_flags+0x89/0x150
> [ 19.096816] dev_change_flags+0x28/0x60
> [ 19.096816] do_setlink+0x290/0x890
> [ 19.096816] rtnl_newlink+0x7cf/0x8e0
> [ 19.096816] rtnetlink_rcv_msg+0xbf/0x1f0
> [ 19.096816] netlink_rcv_skb+0xb9/0xe0
> [ 19.096816] rtnetlink_rcv+0x1e/0x30
> [ 19.096816] netlink_unicast+0x13a/0x2c0
> [ 19.096816] netlink_sendmsg+0x290/0x380
> [ 19.096816] ___sys_sendmsg+0x1e2/0x280
> [ 19.096816] __sys_sendmsg+0x3f/0x80
> [ 19.096816] SyS_socketcall+0x58c/0x6b0
> [ 19.096816] do_fast_syscall_32+0x96/0x1d0
> [ 19.096816] entry_SYSENTER_32+0x4c/0x7b
> [ 19.096816] }
> [ 19.096816] ... key at: [<f837b67c>] __key.61994+0x0/0xffffc984
> [ath9k]
> [ 19.096816] ... acquired at:
> [ 19.096816] check_usage_forwards+0x118/0x120
> [ 19.096816] mark_lock+0x2e4/0x590
> [ 19.096816] __lock_acquire+0x6ae/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] _raw_spin_lock_irqsave+0x45/0x60
> [ 19.096816] ath_isr+0x15e/0x200 [ath9k]
> [ 19.096816] __handle_irq_event_percpu+0x44/0x340
> [ 19.096816] handle_irq_event_percpu+0x1d/0x50
> [ 19.096816] handle_irq_event+0x32/0x60
> [ 19.096816] handle_level_irq+0x81/0x100
> [ 19.096816] handle_irq+0x9c/0xd0
> [ 19.096816] do_IRQ+0x5c/0x120
> [ 19.096816] common_interrupt+0x36/0x3c
> [ 19.096816] _raw_spin_unlock_irqrestore+0x57/0x70
> [ 19.096816] ath9k_config+0x16a/0x1d0 [ath9k]
> [ 19.096816] ieee80211_hw_config+0xa8/0x5f0 [mac80211]
> [ 19.096816] ieee80211_dynamic_ps_enable_work+0x1c3/0x680 [mac80211]
> [ 19.096816] process_one_work+0x1d1/0x580
> [ 19.096816] worker_thread+0x31/0x380
> [ 19.096816] kthread+0xd9/0x110
> [ 19.096816] ret_from_fork+0x19/0x24
>
> [ 19.096816]
> stack backtrace:
> [ 19.096816] CPU: 0 PID: 5 Comm: kworker/u2:0 Not tainted 4.13.0-mgm-ovl+
> #51
> [ 19.096816] Hardware name: FUJITSU SIEMENS LIFEBOOK S6120/FJNB16C, BIOS
> Version 1.26 05/10/2004
> [ 19.096816] Workqueue: phy0 ieee80211_dynamic_ps_enable_work [mac80211]
> [ 19.096816] Call Trace:
> [ 19.096816] <IRQ>
> [ 19.096816] dump_stack+0x16/0x19
> [ 19.096816] print_irq_inversion_bug.part.37+0x16c/0x179
> [ 19.096816] check_usage_forwards+0x118/0x120
> [ 19.096816] ? ret_from_fork+0x19/0x24
> [ 19.096816] ? print_shortest_lock_dependencies+0x1a0/0x1a0
> [ 19.096816] mark_lock+0x2e4/0x590
> [ 19.096816] ? print_shortest_lock_dependencies+0x1a0/0x1a0
> [ 19.096816] __lock_acquire+0x6ae/0x1260
> [ 19.096816] lock_acquire+0xb1/0x1c0
> [ 19.096816] ? ath_isr+0x15e/0x200 [ath9k]
> [ 19.096816] _raw_spin_lock_irqsave+0x45/0x60
> [ 19.096816] ? ath_isr+0x15e/0x200 [ath9k]
> [ 19.096816] ath_isr+0x15e/0x200 [ath9k]
> [ 19.096816] __handle_irq_event_percpu+0x44/0x340
> [ 19.096816] handle_irq_event_percpu+0x1d/0x50
> [ 19.096816] handle_irq_event+0x32/0x60
> [ 19.096816] ? handle_nested_irq+0x100/0x100
> [ 19.096816] handle_level_irq+0x81/0x100
> [ 19.096816] handle_irq+0x9c/0xd0
> [ 19.096816] </IRQ>
> [ 19.096816] do_IRQ+0x5c/0x120
> [ 19.096816] common_interrupt+0x36/0x3c
> [ 19.096816] EIP: _raw_spin_unlock_irqrestore+0x57/0x70
> [ 19.096816] EFLAGS: 00000286 CPU: 0
> [ 19.096816] EAX: f60a3600 EBX: 00000286 ECX: 00000006 EDX: 00000001
> [ 19.096816] ESI: f46c9e68 EDI: f46c8620 EBP: f60b5e8c ESP: f60b5e84
> [ 19.096816] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
> [ 19.096816] ath9k_config+0x16a/0x1d0 [ath9k]
> [ 19.096816] ieee80211_hw_config+0xa8/0x5f0 [mac80211]
> [ 19.096816] ? ieee80211_hw_config+0x1db/0x5f0 [mac80211]
> [ 19.096816] ieee80211_dynamic_ps_enable_work+0x1c3/0x680 [mac80211]
> [ 19.096816] ? process_one_work+0x127/0x580
> [ 19.096816] ? process_one_work+0x127/0x580
> [ 19.096816] process_one_work+0x1d1/0x580
> [ 19.096816] ? process_one_work+0x127/0x580
> [ 19.096816] worker_thread+0x31/0x380
> [ 19.096816] kthread+0xd9/0x110
> [ 19.096816] ? process_one_work+0x580/0x580
> [ 19.096816] ? kthread_create_on_node+0x30/0x30
> [ 19.096816] ret_from_fork+0x19/0x24
>
> Cc: QCA ath9k Development <ath9k-de...@qca.qualcomm.com>
> Cc: Kalle Valo <kv...@codeaurora.org>
> Cc: net...@vger.kernel.org
> Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
> Signed-off-by: Kalle Valo <kv...@qca.qualcomm.com>
Patch applied to ath-next branch of ath.git, thanks.
ba24d63dd374 ath9k: Avoid a potential deadlock
--
https://patchwork.kernel.org/patch/9957575/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
