Hi again,
On 2018-02-12 21:12:48 +0100, Niklas Söderlund wrote:
> Hi Geert,
>
> When doing some testing on v4.16-rc1 I ran across this warning a couple
> of times. I was using the renesas_config from the current master branch
> of renesas-drivers at the time. It do not hit every time but in my
> limited testing I would say ~50%.
I forgot to mention this was on H3 ES2.0.
>
>
> [ 2.634819] ======================================================
> [ 2.640996] WARNING: possible circular locking dependency detected
> [ 2.647176] 4.16.0-rc1-arm64-renesas-00001-g75fb1624ab1a0c5a #34 Not tainted
> [ 2.654222] ------------------------------------------------------
> [ 2.660400] swapper/0/1 is trying to acquire lock:
> [ 2.665188] (prepare_lock){+.+.}, at: [< (ptrval)>] clk_prepare_lock+0x48/0xa8
> [ 2.673123]
> [ 2.673123] but task is already holding lock:
> [ 2.678953] (of_clk_mutex){+.+.}, at: [< (ptrval)>] __of_clk_get_from_provider.part.22+0x3c/0x120
> [ 2.688528]
> [ 2.688528] which lock already depends on the new lock.
> [ 2.688528]
> [ 2.696706]
> [ 2.696706] the existing dependency chain (in reverse order) is:
> [ 2.704186]
> [ 2.704186] -> #5 (of_clk_mutex){+.+.}:
> [ 2.709511] __mutex_lock+0x70/0x888
> [ 2.713606] mutex_lock_nested+0x1c/0x28
> [ 2.718049] __of_clk_get_from_provider.part.22+0x3c/0x120
> [ 2.724054] of_clk_get_from_provider+0x20/0x30
> [ 2.729105] cpg_mssr_attach_dev+0xfc/0x1e0
> [ 2.733809] genpd_add_device+0xbc/0x230
> [ 2.738251] genpd_dev_pm_attach+0xac/0x230
> [ 2.742954] dev_pm_domain_attach+0xc/0x18
> [ 2.747571] platform_drv_probe+0x38/0xb8
> [ 2.752100] driver_probe_device+0x23c/0x310
> [ 2.756890] __driver_attach+0xc4/0xc8
> [ 2.761157] bus_for_each_dev+0x74/0xc8
> [ 2.765511] driver_attach+0x20/0x28
> [ 2.769605] bus_add_driver+0x1b0/0x220
> [ 2.773960] driver_register+0x60/0xf8
> [ 2.778228] __platform_driver_register+0x40/0x48
> [ 2.783456] sh_mobile_i2c_adap_init+0x18/0x20
> [ 2.788423] do_one_initcall+0x9c/0x14c
> [ 2.792778] kernel_init_freeable+0x1dc/0x274
> [ 2.797654] kernel_init+0x10/0x100
> [ 2.801665] ret_from_fork+0x10/0x18
> [ 2.805757]
> [ 2.805757] -> #4 (&genpd->mlock){+.+.}:
> [ 2.811162] __mutex_lock+0x70/0x888
> [ 2.815256] mutex_lock_nested+0x1c/0x28
> [ 2.819699] genpd_lock_mtx+0x14/0x20
> [ 2.823879] genpd_runtime_resume+0x70/0x230
> [ 2.828667] __rpm_callback+0xe0/0x268
> [ 2.832934] rpm_callback+0x20/0x80
> [ 2.836940] rpm_resume+0x344/0x608
> [ 2.840946] __pm_runtime_resume+0x50/0x78
> [ 2.845561] usb_dmac_alloc_chan_resources+0x8c/0xa0
> [ 2.851044] dma_chan_get+0x28/0x80
> [ 2.855051] find_candidate+0xf8/0x188
> [ 2.859319] __dma_request_channel+0x68/0xc8
> [ 2.864108] usb_dmac_of_xlate+0x64/0x98
> [ 2.868550] of_dma_request_slave_channel+0x170/0x270
> [ 2.874121] dma_request_chan+0x38/0x1d0
> [ 2.878568] usbhsf_dma_init.isra.8+0x60/0x108
> [ 2.883531] usbhs_fifo_probe+0x70/0x148
> [ 2.887972] usbhs_probe+0x2c8/0x5e0
> [ 2.892065] platform_drv_probe+0x58/0xb8
> [ 2.896594] driver_probe_device+0x23c/0x310
> [ 2.901382] __driver_attach+0xc4/0xc8
> [ 2.905649] bus_for_each_dev+0x74/0xc8
> [ 2.910004] driver_attach+0x20/0x28
> [ 2.914097] bus_add_driver+0x1b0/0x220
> [ 2.918452] driver_register+0x60/0xf8
> [ 2.922718] __platform_driver_register+0x40/0x48
> [ 2.927942] renesas_usbhs_driver_init+0x18/0x20
> [ 2.933078] do_one_initcall+0x9c/0x14c
> [ 2.937433] kernel_init_freeable+0x1dc/0x274
> [ 2.942309] kernel_init+0x10/0x100
> [ 2.946316] ret_from_fork+0x10/0x18
> [ 2.950407]
> [ 2.950407] -> #3 (dma_list_mutex){+.+.}:
> [ 2.955900] __mutex_lock+0x70/0x888
> [ 2.959994] mutex_lock_nested+0x1c/0x28
> [ 2.964435] __dma_request_channel+0x38/0xc8
> [ 2.969225] usb_dmac_of_xlate+0x64/0x98
> [ 2.973666] of_dma_request_slave_channel+0x170/0x270
> [ 2.979236] dma_request_chan+0x38/0x1d0
> [ 2.983678] usbhsf_dma_init.isra.8+0x60/0x108
> [ 2.988640] usbhs_fifo_probe+0x70/0x148
> [ 2.993081] usbhs_probe+0x2c8/0x5e0
> [ 2.997174] platform_drv_probe+0x58/0xb8
> [ 3.001702] driver_probe_device+0x23c/0x310
> [ 3.006491] __driver_attach+0xc4/0xc8
> [ 3.010759] bus_for_each_dev+0x74/0xc8
> [ 3.015114] driver_attach+0x20/0x28
> [ 3.019208] bus_add_driver+0x1b0/0x220
> [ 3.023562] driver_register+0x60/0xf8
> [ 3.027829] __platform_driver_register+0x40/0x48
> [ 3.033052] renesas_usbhs_driver_init+0x18/0x20
> [ 3.038188] do_one_initcall+0x9c/0x14c
> [ 3.042543] kernel_init_freeable+0x1dc/0x274
> [ 3.047419] kernel_init+0x10/0x100
> [ 3.051426] ret_from_fork+0x10/0x18
> [ 3.055517]
> [ 3.055517] -> #2 (of_dma_lock){+.+.}:
> [ 3.060749] __mutex_lock+0x70/0x888
> [ 3.064843] mutex_lock_nested+0x1c/0x28
> [ 3.069284] of_dma_request_slave_channel+0x12c/0x270
> [ 3.074855] dma_request_chan+0x38/0x1d0
> [ 3.079300] rcar_i2c_master_xfer+0x1b4/0x458
> [ 3.084176] __i2c_transfer+0x11c/0x260
> [ 3.088530] i2c_transfer+0x60/0xc8
> [ 3.092537] i2c_smbus_xfer_emulated+0x14c/0x5d0
> [ 3.097673] i2c_smbus_xfer+0x128/0x1a0
> [ 3.102027] i2c_smbus_read_byte_data+0x40/0x70
> [ 3.107076] cs2000_bset.isra.1+0x2c/0x68
> [ 3.111604] __cs2000_set_rate.constprop.7+0x80/0x148
> [ 3.117174] cs2000_probe+0xd4/0x260
> [ 3.121267] i2c_device_probe+0x2a4/0x2c8
> [ 3.125796] driver_probe_device+0x23c/0x310
> [ 3.130584] __device_attach_driver+0x94/0xd8
> [ 3.135460] bus_for_each_drv+0x68/0xd0
> [ 3.139813] __device_attach+0xd8/0x138
> [ 3.144168] device_initial_probe+0x10/0x18
> [ 3.148870] bus_probe_device+0x94/0xa0
> [ 3.153224] device_add+0x3b8/0x5e0
> [ 3.157230] device_register+0x1c/0x28
> [ 3.161497] i2c_new_device+0x138/0x338
> [ 3.165852] of_i2c_register_device+0x114/0x1e8
> [ 3.170900] of_i2c_register_devices+0x7c/0xf8
> [ 3.175862] i2c_register_adapter+0x160/0x418
> [ 3.180737] __i2c_add_numbered_adapter+0x60/0x98
> [ 3.185959] i2c_add_adapter+0xa4/0xd0
> [ 3.190227] i2c_add_numbered_adapter+0x24/0x30
> [ 3.195276] rcar_i2c_probe+0x330/0x418
> [ 3.199629] platform_drv_probe+0x58/0xb8
> [ 3.204157] driver_probe_device+0x23c/0x310
> [ 3.208946] __driver_attach+0xc4/0xc8
> [ 3.213213] bus_for_each_dev+0x74/0xc8
> [ 3.217567] driver_attach+0x20/0x28
> [ 3.221661] bus_add_driver+0x1b0/0x220
> [ 3.226015] driver_register+0x60/0xf8
> [ 3.230282] __platform_driver_register+0x40/0x48
> [ 3.235505] rcar_i2c_driver_init+0x18/0x20
> [ 3.240207] do_one_initcall+0x9c/0x14c
> [ 3.244561] kernel_init_freeable+0x1dc/0x274
> [ 3.249437] kernel_init+0x10/0x100
> [ 3.253444] ret_from_fork+0x10/0x18
> [ 3.257536]
> [ 3.257536] -> #1 (i2c_register_adapter){+.+.}:
> [ 3.263549] rt_mutex_lock+0x30/0x50
> [ 3.267642] i2c_adapter_lock_bus+0x10/0x18
> [ 3.272343] i2c_transfer+0xa8/0xc8
> [ 3.276350] i2c_smbus_xfer_emulated+0x14c/0x5d0
> [ 3.281486] i2c_smbus_xfer+0x128/0x1a0
> [ 3.285840] i2c_smbus_read_byte_data+0x40/0x70
> [ 3.290889] cs2000_recalc_rate+0x38/0x90
> [ 3.295417] clk_register+0x390/0x6e0
> [ 3.299598] clk_hw_register+0xc/0x20
> [ 3.303778] cs2000_probe+0x134/0x260
> [ 3.307957] i2c_device_probe+0x2a4/0x2c8
> [ 3.312485] driver_probe_device+0x23c/0x310
> [ 3.317274] __device_attach_driver+0x94/0xd8
> [ 3.322150] bus_for_each_drv+0x68/0xd0
> [ 3.326504] __device_attach+0xd8/0x138
> [ 3.330858] device_initial_probe+0x10/0x18
> [ 3.335560] bus_probe_device+0x94/0xa0
> [ 3.339913] device_add+0x3b8/0x5e0
> [ 3.343919] device_register+0x1c/0x28
> [ 3.348186] i2c_new_device+0x138/0x338
> [ 3.352540] of_i2c_register_device+0x114/0x1e8
> [ 3.357589] of_i2c_register_devices+0x7c/0xf8
> [ 3.362551] i2c_register_adapter+0x160/0x418
> [ 3.367426] __i2c_add_numbered_adapter+0x60/0x98
> [ 3.372648] i2c_add_adapter+0xa4/0xd0
> [ 3.376915] i2c_add_numbered_adapter+0x24/0x30
> [ 3.381964] rcar_i2c_probe+0x330/0x418
> [ 3.386318] platform_drv_probe+0x58/0xb8
> [ 3.390846] driver_probe_device+0x23c/0x310
> [ 3.395634] __driver_attach+0xc4/0xc8
> [ 3.399902] bus_for_each_dev+0x74/0xc8
> [ 3.404256] driver_attach+0x20/0x28
> [ 3.408350] bus_add_driver+0x1b0/0x220
> [ 3.412704] driver_register+0x60/0xf8
> [ 3.416971] __platform_driver_register+0x40/0x48
> [ 3.422194] rcar_i2c_driver_init+0x18/0x20
> [ 3.426896] do_one_initcall+0x9c/0x14c
> [ 3.431250] kernel_init_freeable+0x1dc/0x274
> [ 3.436126] kernel_init+0x10/0x100
> [ 3.440132] ret_from_fork+0x10/0x18
> [ 3.444224]
> [ 3.444224] -> #0 (prepare_lock){+.+.}:
> [ 3.449544] lock_acquire+0x48/0x68
> [ 3.453551] __mutex_lock+0x70/0x888
> [ 3.457645] mutex_lock_nested+0x1c/0x28
> [ 3.462086] clk_prepare_lock+0x48/0xa8
> [ 3.466440] __clk_create_clk.part.20+0x64/0xa0
> [ 3.471489] __of_clk_get_from_provider.part.22+0xd0/0x120
> [ 3.477494] __of_clk_get_from_provider+0x10/0x20
> [ 3.482717] __of_clk_get_by_name+0x9c/0x158
> [ 3.487505] clk_get+0x2c/0x78
> [ 3.491078] devm_clk_get+0x4c/0xa8
> [ 3.495090] rsnd_dvc_probe+0x15c/0x210
> [ 3.499444] rsnd_probe+0xcc/0x480
> [ 3.503363] platform_drv_probe+0x58/0xb8
> [ 3.507891] driver_probe_device+0x23c/0x310
> [ 3.512680] __driver_attach+0xc4/0xc8
> [ 3.516947] bus_for_each_dev+0x74/0xc8
> [ 3.521301] driver_attach+0x20/0x28
> [ 3.525395] bus_add_driver+0x1b0/0x220
> [ 3.529749] driver_register+0x60/0xf8
> [ 3.534016] __platform_driver_register+0x40/0x48
> [ 3.539240] rsnd_driver_init+0x18/0x20
> [ 3.543595] do_one_initcall+0x9c/0x14c
> [ 3.547949] kernel_init_freeable+0x1dc/0x274
> [ 3.552825] kernel_init+0x10/0x100
> [ 3.556832] ret_from_fork+0x10/0x18
> [ 3.560924]
> [ 3.560924] other info that might help us debug this:
> [ 3.560924]
> [ 3.568928] Chain exists of:
> [ 3.568928] prepare_lock --> &genpd->mlock --> of_clk_mutex
> [ 3.568928]
> [ 3.579026] Possible unsafe locking scenario:
> [ 3.579026]
> [ 3.584943] CPU0 CPU1
> [ 3.589469] ---- ----
> [ 3.593995] lock(of_clk_mutex);
> [ 3.597309] lock(&genpd->mlock);
> [ 3.603228] lock(of_clk_mutex);
> [ 3.609060] lock(prepare_lock);
> [ 3.612374]
> [ 3.612374] *** DEADLOCK ***
> [ 3.612374]
> [ 3.618294] 3 locks held by swapper/0/1:
> [ 3.622212] #0: (&dev->mutex){....}, at: [< (ptrval)>] __driver_attach+0x4c/0xc8
> [ 3.630397] #1: (&dev->mutex){....}, at: [< (ptrval)>] __driver_attach+0x5c/0xc8
> [ 3.638581] #2: (of_clk_mutex){+.+.}, at: [< (ptrval)>] __of_clk_get_from_provider.part.22+0x3c/0x120
> [ 3.648589]
> [ 3.648589] stack backtrace:
> [ 3.652946] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.16.0-rc1-arm64-renesas-00001-g75fb1624ab1a0c5a #34
> [ 3.662599] Hardware name: Renesas Salvator-X 2nd version board based on r8a7795 ES2.0+ (DT)
> [ 3.671036] Call trace:
> [ 3.673481] dump_backtrace+0x0/0x1c8
> [ 3.677142] show_stack+0x14/0x20
> [ 3.680455] dump_stack+0xbc/0xf8
> [ 3.683767] print_circular_bug.isra.19+0x1d4/0x2e0
> [ 3.688642] __lock_acquire+0x15ec/0x1890
> [ 3.692648] lock_acquire+0x48/0x68
> [ 3.696134] __mutex_lock+0x70/0x888
> [ 3.699707] mutex_lock_nested+0x1c/0x28
> [ 3.703626] clk_prepare_lock+0x48/0xa8
> [ 3.707459] __clk_create_clk.part.20+0x64/0xa0
> [ 3.711987] __of_clk_get_from_provider.part.22+0xd0/0x120
> [ 3.717471] __of_clk_get_from_provider+0x10/0x20
> [ 3.722172] __of_clk_get_by_name+0x9c/0x158
> [ 3.726439] clk_get+0x2c/0x78
> [ 3.729490] devm_clk_get+0x4c/0xa8
> [ 3.732976] rsnd_dvc_probe+0x15c/0x210
> [ 3.736808] rsnd_probe+0xcc/0x480
> [ 3.740207] platform_drv_probe+0x58/0xb8
> [ 3.744213] driver_probe_device+0x23c/0x310
> [ 3.748481] __driver_attach+0xc4/0xc8
> [ 3.752227] bus_for_each_dev+0x74/0xc8
> [ 3.756061] driver_attach+0x20/0x28
> [ 3.759633] bus_add_driver+0x1b0/0x220
> [ 3.763466] driver_register+0x60/0xf8
> [ 3.767212] __platform_driver_register+0x40/0x48
> [ 3.771913] rsnd_driver_init+0x18/0x20
> [ 3.775747] do_one_initcall+0x9c/0x14c
> [ 3.779580] kernel_init_freeable+0x1dc/0x274
> [ 3.783934] kernel_init+0x10/0x100
> [ 3.787419] ret_from_fork+0x10/0x18
>
--
Regards,
Niklas Söderlund
