[PW_SID:914536] Bluetooth: iso: Fix warnings #2021
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This patch adds workflow files for ci: [schedule_work.yml] - The workflow file for scheduled work - Sync the repo with upstream repo and rebase the workflow branch - Review the patches in the patchwork and creates the PR if needed [ci.yml] - The workflow file for CI tasks - Run CI tests when PR is created
This fixes circular locking dependency warnings, by ensuring the hci_dev_lock -> lock_sk order for all ISO functions. Below is an example of a warning generated because of locking dependencies: [ 75.307983] ====================================================== [ 75.307984] WARNING: possible circular locking dependency detected [ 75.307985] 6.12.0-rc6+ #22 Not tainted [ 75.307987] ------------------------------------------------------ [ 75.307987] kworker/u81:2/2623 is trying to acquire lock: [ 75.307988] ffff8fde1769da58 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO) at: iso_connect_cfm+0x253/0x840 [bluetooth] [ 75.308021] but task is already holding lock: [ 75.308022] ffff8fdd61a10078 (&hdev->lock) at: hci_le_per_adv_report_evt+0x47/0x2f0 [bluetooth] [ 75.308053] which lock already depends on the new lock. [ 75.308054] the existing dependency chain (in reverse order) is: [ 75.308055] -> #1 (&hdev->lock){+.+.}-{3:3}: [ 75.308057] __mutex_lock+0xad/0xc50 [ 75.308061] mutex_lock_nested+0x1b/0x30 [ 75.308063] iso_sock_listen+0x143/0x5c0 [bluetooth] [ 75.308085] __sys_listen_socket+0x49/0x60 [ 75.308088] __x64_sys_listen+0x4c/0x90 [ 75.308090] x64_sys_call+0x2517/0x25f0 [ 75.308092] do_syscall_64+0x87/0x150 [ 75.308095] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 75.308098] -> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}: [ 75.308100] __lock_acquire+0x155e/0x25f0 [ 75.308103] lock_acquire+0xc9/0x300 [ 75.308105] lock_sock_nested+0x32/0x90 [ 75.308107] iso_connect_cfm+0x253/0x840 [bluetooth] [ 75.308128] hci_connect_cfm+0x6c/0x190 [bluetooth] [ 75.308155] hci_le_per_adv_report_evt+0x27b/0x2f0 [bluetooth] [ 75.308180] hci_le_meta_evt+0xe7/0x200 [bluetooth] [ 75.308206] hci_event_packet+0x21f/0x5c0 [bluetooth] [ 75.308230] hci_rx_work+0x3ae/0xb10 [bluetooth] [ 75.308254] process_one_work+0x212/0x740 [ 75.308256] worker_thread+0x1bd/0x3a0 [ 75.308258] kthread+0xe4/0x120 [ 75.308259] ret_from_fork+0x44/0x70 [ 75.308261] ret_from_fork_asm+0x1a/0x30 [ 75.308263] other info that might help us debug this: [ 75.308264] Possible unsafe locking scenario: [ 75.308264] CPU0 CPU1 [ 75.308265] ---- ---- [ 75.308265] lock(&hdev->lock); [ 75.308267] lock(sk_lock- AF_BLUETOOTH-BTPROTO_ISO); [ 75.308268] lock(&hdev->lock); [ 75.308269] lock(sk_lock-AF_BLUETOOTH-BTPROTO_ISO); [ 75.308270] *** DEADLOCK *** [ 75.308271] 4 locks held by kworker/u81:2/2623: [ 75.308272] #0: ffff8fdd66e52148 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x443/0x740 [ 75.308276] #1: ffffafb488b7fe48 ((work_completion)(&hdev->rx_work)), at: process_one_work+0x1ce/0x740 [ 75.308280] #2: ffff8fdd61a10078 (&hdev->lock){+.+.}-{3:3} at: hci_le_per_adv_report_evt+0x47/0x2f0 [bluetooth] [ 75.308304] #3: ffffffffb6ba4900 (rcu_read_lock){....}-{1:2}, at: hci_connect_cfm+0x29/0x190 [bluetooth] Signed-off-by: Iulia Tanasescu <[email protected]>
Since hci_get_route holds the device before returning, the hdev should be released with hci_dev_put at the end of iso_listen_bis even if the function returns with an error. Signed-off-by: Iulia Tanasescu <[email protected]>
This updates iso_sock_accept to use nested locking for the parent socket, to avoid lockdep warnings caused because the parent and child sockets are locked by the same thread: [ 41.585683] ============================================ [ 41.585688] WARNING: possible recursive locking detected [ 41.585694] 6.12.0-rc6+ #22 Not tainted [ 41.585701] -------------------------------------------- [ 41.585705] iso-tester/3139 is trying to acquire lock: [ 41.585711] ffff988b29530a58 (sk_lock-AF_BLUETOOTH) at: bt_accept_dequeue+0xe3/0x280 [bluetooth] [ 41.585905] but task is already holding lock: [ 41.585909] ffff988b29533a58 (sk_lock-AF_BLUETOOTH) at: iso_sock_accept+0x61/0x2d0 [bluetooth] [ 41.586064] other info that might help us debug this: [ 41.586069] Possible unsafe locking scenario: [ 41.586072] CPU0 [ 41.586076] ---- [ 41.586079] lock(sk_lock-AF_BLUETOOTH); [ 41.586086] lock(sk_lock-AF_BLUETOOTH); [ 41.586093] *** DEADLOCK *** [ 41.586097] May be due to missing lock nesting notation [ 41.586101] 1 lock held by iso-tester/3139: [ 41.586107] #0: ffff988b29533a58 (sk_lock-AF_BLUETOOTH) at: iso_sock_accept+0x61/0x2d0 [bluetooth] Signed-off-by: Iulia Tanasescu <[email protected]>
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This fixes circular locking dependency warnings, by ensuring
the hci_dev_lock -> lock_sk order for all ISO functions.
Below is an example of a warning generated because of locking
dependencies:
[ 75.307983] ======================================================
[ 75.307984] WARNING: possible circular locking dependency detected
[ 75.307985] 6.12.0-rc6+ #22 Not tainted
[ 75.307987] ------------------------------------------------------
[ 75.307987] kworker/u81:2/2623 is trying to acquire lock:
[ 75.307988] ffff8fde1769da58 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO)
at: iso_connect_cfm+0x253/0x840 [bluetooth]
[ 75.308021]
but task is already holding lock:
[ 75.308022] ffff8fdd61a10078 (&hdev->lock)
at: hci_le_per_adv_report_evt+0x47/0x2f0 [bluetooth]
[ 75.308053]
which lock already depends on the new lock.
[ 75.308054]
the existing dependency chain (in reverse order) is:
[ 75.308055]
-> #1 (&hdev->lock){+.+.}-{3:3}:
[ 75.308057] __mutex_lock+0xad/0xc50
[ 75.308061] mutex_lock_nested+0x1b/0x30
[ 75.308063] iso_sock_listen+0x143/0x5c0 [bluetooth]
[ 75.308085] __sys_listen_socket+0x49/0x60
[ 75.308088] __x64_sys_listen+0x4c/0x90
[ 75.308090] x64_sys_call+0x2517/0x25f0
[ 75.308092] do_syscall_64+0x87/0x150
[ 75.308095] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 75.308098]
-> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}:
[ 75.308100] __lock_acquire+0x155e/0x25f0
[ 75.308103] lock_acquire+0xc9/0x300
[ 75.308105] lock_sock_nested+0x32/0x90
[ 75.308107] iso_connect_cfm+0x253/0x840 [bluetooth]
[ 75.308128] hci_connect_cfm+0x6c/0x190 [bluetooth]
[ 75.308155] hci_le_per_adv_report_evt+0x27b/0x2f0 [bluetooth]
[ 75.308180] hci_le_meta_evt+0xe7/0x200 [bluetooth]
[ 75.308206] hci_event_packet+0x21f/0x5c0 [bluetooth]
[ 75.308230] hci_rx_work+0x3ae/0xb10 [bluetooth]
[ 75.308254] process_one_work+0x212/0x740
[ 75.308256] worker_thread+0x1bd/0x3a0
[ 75.308258] kthread+0xe4/0x120
[ 75.308259] ret_from_fork+0x44/0x70
[ 75.308261] ret_from_fork_asm+0x1a/0x30
[ 75.308263]
other info that might help us debug this:
[ 75.308264] Possible unsafe locking scenario:
[ 75.308264] CPU0 CPU1
[ 75.308265] ---- ----
[ 75.308265] lock(&hdev->lock);
[ 75.308267] lock(sk_lock-
AF_BLUETOOTH-BTPROTO_ISO);
[ 75.308268] lock(&hdev->lock);
[ 75.308269] lock(sk_lock-AF_BLUETOOTH-BTPROTO_ISO);
[ 75.308270]
*** DEADLOCK ***
[ 75.308271] 4 locks held by kworker/u81:2/2623:
[ 75.308272] #0: ffff8fdd66e52148 ((wq_completion)hci0#2){+.+.}-{0:0},
at: process_one_work+0x443/0x740
[ 75.308276] #1: ffffafb488b7fe48 ((work_completion)(&hdev->rx_work)),
at: process_one_work+0x1ce/0x740
[ 75.308280] #2: ffff8fdd61a10078 (&hdev->lock){+.+.}-{3:3}
at: hci_le_per_adv_report_evt+0x47/0x2f0 [bluetooth]
[ 75.308304] #3: ffffffffb6ba4900 (rcu_read_lock){....}-{1:2},
at: hci_connect_cfm+0x29/0x190 [bluetooth]
Signed-off-by: Iulia Tanasescu [email protected]
net/bluetooth/iso.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)