Odroid XU4 deadlock
From: Anand Moon
Date: Fri Apr 08 2016 - 09:52:01 EST
Hi All,
I am observing this deadlock or warning on my Odroid XU4.
I thinks the is related to clk from exynos5_i2c_xfer .... clk_prepare_enable
but I am not able to figure out which clk.
[ 11.640221] ======================================================
[ 11.646343] [ INFO: possible circular locking dependency detected ]
[ 11.652590] 4.6.0-rc2-xu4ml #35 Not tainted
[ 11.656749] -------------------------------------------------------
[ 11.662992] kworker/1:1/85 is trying to acquire lock:
[ 11.668010] (prepare_lock){+.+...}, at: [<c05bfed8>]
clk_prepare_lock+0x50/0xf8
[ 11.675375]
[ 11.675375] but task is already holding lock:
[ 11.681185] (sec_core:428:(regmap)->lock){+.+...}, at:
[<c0481aec>] regmap_read+0x2c/0x5c
[ 11.689417]
[ 11.689417] which lock already depends on the new lock.
[ 11.689417]
[ 11.697561]
[ 11.697561] the existing dependency chain (in reverse order) is:
[ 11.705008]
[ 11.705008] -> #1 (sec_core:428:(regmap)->lock){+.+...}:
[ 11.710467] [<c0482d30>] regmap_update_bits_base+0x30/0x70
[ 11.716545] [<c05c617c>] s2mps11_clk_prepare+0x30/0x38
[ 11.722262] [<c05c01f0>] clk_core_prepare+0x98/0xbc
[ 11.727711] [<c05c12bc>] clk_prepare+0x1c/0x2c
[ 11.732734] [<c0556fe4>] s3c_rtc_probe+0x2d0/0x43c
[ 11.738108] [<c046b9fc>] platform_drv_probe+0x4c/0xb0
[ 11.743749] [<c046a1fc>] driver_probe_device+0x20c/0x2b8
[ 11.749641] [<c0468594>] bus_for_each_drv+0x60/0x94
[ 11.755103] [<c0469f10>] __device_attach+0xb4/0x118
[ 11.760558] [<c04693b4>] bus_probe_device+0x88/0x90
[ 11.766020] [<c0469850>] deferred_probe_work_func+0x6c/0x9c
[ 11.772169] [<c013b52c>] process_one_work+0x1a8/0x514
[ 11.777806] [<c013b8d0>] worker_thread+0x38/0x56c
[ 11.783082] [<c0141d14>] kthread+0xf4/0x10c
[ 11.787847] [<c0107950>] ret_from_fork+0x14/0x24
[ 11.793050]
[ 11.793050] -> #0 (prepare_lock){+.+...}:
[ 11.797212] [<c0768dd8>] mutex_lock_nested+0x78/0x4dc
[ 11.802845] [<c05bfed8>] clk_prepare_lock+0x50/0xf8
[ 11.808304] [<c05c19c4>] clk_unprepare+0x1c/0x2c
[ 11.813499] [<c055d720>] exynos5_i2c_xfer+0x1dc/0x304
[ 11.819129] [<c0559620>] __i2c_transfer+0x13c/0x278
[ 11.824589] [<c05597f0>] i2c_transfer+0x94/0xc4
[ 11.829701] [<c04868f0>] regmap_i2c_read+0x48/0x64
[ 11.835074] [<c0482048>] _regmap_raw_read+0xb4/0x114
[ 11.840630] [<c04820cc>] _regmap_bus_read+0x24/0x58
[ 11.846084] [<c0481a68>] _regmap_read+0x60/0xb8
[ 11.851201] [<c0481afc>] regmap_read+0x3c/0x5c
[ 11.856224] [<c03e2354>] regulator_get_voltage_sel_regmap+0x20/0x54
[ 11.863109] [<c03dc5d4>] _regulator_get_voltage+0x20/0xb8
[ 11.863141] [<c03df058>] _regulator_do_set_voltage+0x240/0x370
[ 11.863173] [<c03df254>] regulator_set_voltage_unlocked+0xcc/0x230
[ 11.863205] [<c03df3e0>] regulator_set_voltage+0x28/0x54
[ 11.863234] [<c0478a94>] _set_opp_voltage+0x30/0x98
[ 11.863264] [<c0479ba8>] dev_pm_opp_set_rate+0x1e0/0x540
[ 11.863337] [<c0580824>] __cpufreq_driver_target+0x168/0x290
[ 11.863375] [<c0583b48>] od_dbs_timer+0xdc/0x164
[ 11.863407] [<c0584114>] dbs_work_handler+0x30/0x58
[ 11.863437] [<c013b52c>] process_one_work+0x1a8/0x514
[ 11.863465] [<c013b8d0>] worker_thread+0x38/0x56c
[ 11.863496] [<c0141d14>] kthread+0xf4/0x10c
[ 11.863528] [<c0107950>] ret_from_fork+0x14/0x24
[ 11.863538]
[ 11.863538] other info that might help us debug this:
[ 11.863538]
[ 11.863548] Possible unsafe locking scenario:
[ 11.863548]
[ 11.863557] CPU0 CPU1
[ 11.863565] ---- ----
[ 11.863589] lock(sec_core:428:(regmap)->lock);
[ 11.863612] lock(prepare_lock);
[ 11.863634] lock(sec_core:428:(regmap)->lock);
[ 11.863655] lock(prepare_lock);
[ 11.863664]
[ 11.863664] *** DEADLOCK ***
[ 11.863664]
[ 11.863678] 5 locks held by kworker/1:1/85:
[ 11.863734] #0: ("events"){.+.+.+}, at: [<c013b4bc>]
process_one_work+0x138/0x514
[ 11.863788] #1: ((&policy_dbs->work)){+.+...}, at: [<c013b4bc>]
process_one_work+0x138/0x514
[ 11.863845] #2: (&policy_dbs->timer_mutex){+.+...}, at:
[<c0584108>] dbs_work_handler+0x24/0x58
[ 11.863899] #3: (&rdev->mutex){+.+.+.}, at: [<c03dc980>]
regulator_lock_supply+0x1c/0x3c
[ 11.863950] #4: (sec_core:428:(regmap)->lock){+.+...}, at:
[<c0481aec>] regmap_read+0x2c/0x5c
[ 11.863959]
[ 11.863959] stack backtrace:
[ 11.863984] CPU: 1 PID: 85 Comm: kworker/1:1 Not tainted 4.6.0-rc2-xu4ml #35
[ 11.863995] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[ 11.864030] Workqueue: events dbs_work_handler
[ 11.864098] [<c010ee2c>] (unwind_backtrace) from [<c010bab8>]
(show_stack+0x10/0x14)
[ 11.864139] [<c010bab8>] (show_stack) from [<c037d460>]
(dump_stack+0x98/0xc4)
[ 11.864189] [<c037d460>] (dump_stack) from [<c016f198>]
(print_circular_bug+0x214/0x33c)
[ 11.864229] [<c016f198>] (print_circular_bug) from [<c0172e24>]
(__lock_acquire+0x1c2c/0x202c)
[ 11.864268] [<c0172e24>] (__lock_acquire) from [<c0173e14>]
(lock_acquire+0xa8/0xd0)
[ 11.864304] [<c0173e14>] (lock_acquire) from [<c0768dd8>]
(mutex_lock_nested+0x78/0x4dc)
[ 11.864342] [<c0768dd8>] (mutex_lock_nested) from [<c05bfed8>]
(clk_prepare_lock+0x50/0xf8)
[ 11.864377] [<c05bfed8>] (clk_prepare_lock) from [<c05c19c4>]
(clk_unprepare+0x1c/0x2c)
[ 11.864414] [<c05c19c4>] (clk_unprepare) from [<c055d720>]
(exynos5_i2c_xfer+0x1dc/0x304)
[ 11.864452] [<c055d720>] (exynos5_i2c_xfer) from [<c0559620>]
(__i2c_transfer+0x13c/0x278)
[ 11.864484] [<c0559620>] (__i2c_transfer) from [<c05597f0>]
(i2c_transfer+0x94/0xc4)
[ 11.864518] [<c05597f0>] (i2c_transfer) from [<c04868f0>]
(regmap_i2c_read+0x48/0x64)
[ 11.864551] [<c04868f0>] (regmap_i2c_read) from [<c0482048>]
(_regmap_raw_read+0xb4/0x114)
[ 11.864580] [<c0482048>] (_regmap_raw_read) from [<c04820cc>]
(_regmap_bus_read+0x24/0x58)
[ 11.864617] [<c04820cc>] (_regmap_bus_read) from [<c0481a68>]
(_regmap_read+0x60/0xb8)
[ 11.864651] [<c0481a68>] (_regmap_read) from [<c0481afc>]
(regmap_read+0x3c/0x5c)
[ 11.864687] [<c0481afc>] (regmap_read) from [<c03e2354>]
(regulator_get_voltage_sel_regmap+0x20/0x54)
[ 11.864725] [<c03e2354>] (regulator_get_voltage_sel_regmap) from
[<c03dc5d4>] (_regulator_get_voltage+0x20/0xb8)
[ 11.864761] [<c03dc5d4>] (_regulator_get_voltage) from [<c03df058>]
(_regulator_do_set_voltage+0x240/0x370)
[ 11.864798] [<c03df058>] (_regulator_do_set_voltage) from
[<c03df254>] (regulator_set_voltage_unlocked+0xcc/0x230)
[ 11.864835] [<c03df254>] (regulator_set_voltage_unlocked) from
[<c03df3e0>] (regulator_set_voltage+0x28/0x54)
[ 11.864868] [<c03df3e0>] (regulator_set_voltage) from [<c0478a94>]
(_set_opp_voltage+0x30/0x98)
[ 11.864901] [<c0478a94>] (_set_opp_voltage) from [<c0479ba8>]
(dev_pm_opp_set_rate+0x1e0/0x540)
[ 11.864935] [<c0479ba8>] (dev_pm_opp_set_rate) from [<c0580824>]
(__cpufreq_driver_target+0x168/0x290)
[ 11.864973] [<c0580824>] (__cpufreq_driver_target) from
[<c0583b48>] (od_dbs_timer+0xdc/0x164)
[ 11.865011] [<c0583b48>] (od_dbs_timer) from [<c0584114>]
(dbs_work_handler+0x30/0x58)
[ 11.865048] [<c0584114>] (dbs_work_handler) from [<c013b52c>]
(process_one_work+0x1a8/0x514)
[ 11.865082] [<c013b52c>] (process_one_work) from [<c013b8d0>]
(worker_thread+0x38/0x56c)
[ 11.865118] [<c013b8d0>] (worker_thread) from [<c0141d14>]
(kthread+0xf4/0x10c)
[ 11.865156] [<c0141d14>] (kthread) from [<c0107950>]
(ret_from_fork+0x14/0x24)
Best Regards
-Anand Moon