* restart callback not supposed to sleep?
@ 2012-08-20 8:24 Uwe Kleine-König
2012-08-20 8:57 ` Russell King - ARM Linux
2012-08-20 8:57 ` Lothar Waßmann
0 siblings, 2 replies; 7+ messages in thread
From: Uwe Kleine-König @ 2012-08-20 8:24 UTC (permalink / raw)
To: linux-arm-kernel
Hello,
while triggering a reboot via sysrq on an ARM machine I saw a "BUG:
sleeping function called from invalid context" message (details below).
The reason is that the sysrq handler is calling the restart hook in irq
context. So what should be done about that? The obvious possiblities
are:
a) ignore the problem as it won't result in problems (and maybe somehow
silence the warnign); or
b) make the restart hook atomic; or
c) assert sysrq not calling the hook in atomic mode
What do you think?
Best regards
Uwe
[ 357.957733] SysRq : Resetting
[ 357.960772] BUG: sleeping function called from invalid context at kernel/mutex.c:269
[ 357.973053] in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper
[ 357.979508] 2 locks held by swapper/0:
[ 357.983268] #0: (&port_lock_key){-.-...}, at: [<801df9ec>] imx_rxint+0x24/0x2a4
[ 357.990887] #1: (sysrq_key_table_lock){-.....}, at: [<801cda7c>] __handle_sysrq+0x1c/0x188
[ 357.999442] Backtrace:
[ 358.001962] [<80010e9c>] (dump_backtrace+0x0/0x10c) from [<80365da0>] (dump_stack+0x18/0x1c)
[ 358.010415] r6:0000166c r5:804dbc00 r4:804ce000 r3:60000113
[ 358.016200] [<80365d88>] (dump_stack+0x0/0x1c) from [<80040f70>] (__might_sleep+0xe0/0x11c)
[ 358.024590] [<80040e90>] (__might_sleep+0x0/0x11c) from [<80369d8c>] (mutex_lock_nested+0x2c/0x2d0)
[ 358.033649] r6:804e90dc r5:80425b9c r4:804fb224
[ 358.038372] [<80369d60>] (mutex_lock_nested+0x0/0x2d0) from [<8028ffdc>] (clk_get_sys+0x24/0x110)
[ 358.047290] [<8028ffb8>] (clk_get_sys+0x0/0x110) from [<800188c8>] (mxc_restart+0x18/0xb8)
[ 358.055588] [<800188b0>] (mxc_restart+0x0/0xb8) from [<8000ed70>] (machine_restart+0x24/0x60)
[ 358.064126] r5:804e4d70 r4:804dab3c
[ 358.067863] [<8000ed4c>] (machine_restart+0x0/0x60) from [<8002d554>] (emergency_restart+0x1c/0x20)
[ 358.076961] r5:00000062 r4:804dab3c
[ 358.080615] [<8002d538>] (emergency_restart+0x0/0x20) from [<801cd93c>] (sysrq_handle_reboot+0x1c/0x20)
[ 358.090073] [<801cd920>] (sysrq_handle_reboot+0x0/0x20) from [<801cdb6c>] (__handle_sysrq+0x10c/0x188)
[ 358.099441] [<801cda60>] (__handle_sysrq+0x0/0x188) from [<801cde00>] (handle_sysrq+0x30/0x38)
[ 358.108115] [<801cddd0>] (handle_sysrq+0x0/0x38) from [<801dfba8>] (imx_rxint+0x1e0/0x2a4)
[ 358.116440] [<801df9c8>] (imx_rxint+0x0/0x2a4) from [<801e0b0c>] (imx_int+0xa0/0xb8)
[ 358.124224] [<801e0a6c>] (imx_int+0x0/0xb8) from [<80063f44>] (handle_irq_event_percpu+0x54/0x1bc)
[ 358.133226] r6:00000000 r5:87808e90 r4:870e9000 r3:801e0a6c
[ 358.139026] [<80063ef0>] (handle_irq_event_percpu+0x0/0x1bc) from [<800640f0>] (handle_irq_event+0x44/0x64)
[ 358.148834] [<800640ac>] (handle_irq_event+0x0/0x64) from [<80066414>] (handle_level_irq+0x94/0xf0)
[ 358.157923] r6:00000000 r5:87808e90 r4:87808e40 r3:00020000
[ 358.163698] [<80066380>] (handle_level_irq+0x0/0xf0) from [<800637a8>] (generic_handle_irq+0x28/0x38)
[ 358.172961] r5:0000003d r4:0000003d
[ 358.176635] [<80063780>] (generic_handle_irq+0x0/0x38) from [<8000e92c>] (handle_IRQ+0x38/0x8c)
[ 358.185347] r4:804e4da4 r3:000000b4
[ 358.189023] [<8000e8f4>] (handle_IRQ+0x0/0x8c) from [<800084c4>] (avic_handle_irq+0x3c/0x5c)
[ 358.197502] r6:0000ffff r5:804cff18 r4:80502e58 r3:00000010
[ 358.203272] [<80008488>] (avic_handle_irq+0x0/0x5c) from [<8000dd24>] (__irq_svc+0x44/0x58)
[ 358.211670] Exception stack(0x804cff18 to 0x804cff60)
[ 358.216769] ff00: 00000001 00000001
[ 358.224977] ff20: 00000000 804d8600 804ce000 80502a68 804d98d0 804ce000 80004008 4117b363
[ 358.233211] ff40: 804c1cec 804cff6c 804cff30 804cff60 800530e0 8000eaac 20000013 ffffffff
[ 358.241430] r6:ffffffff r5:20000013 r4:8000eaac r3:804d8600
[ 358.247229] [<8000ea84>] (default_idle+0x0/0x40) from [<8000ec88>] (cpu_idle+0x64/0xd0)
[ 358.255281] [<8000ec24>] (cpu_idle+0x0/0xd0) from [<803605a8>] (rest_init+0xc4/0xec)
[ 358.263069] r7:00000002 r6:00000001 r5:804dc534 r4:804ce000
[ 358.268876] [<803604e4>] (rest_init+0x0/0xec) from [<804a27d0>] (start_kernel+0x2ac/0x2fc)
[ 358.277184] r7:80b4e620 r6:804c31bc r5:805029c0 r4:804d6140
[ 358.282954] [<804a2524>] (start_kernel+0x0/0x2fc) from [<80008040>] (0x80008040)
[ 358.290400] BUG: scheduling while atomic: swapper/0/0x40010004
[ 358.296277] 2 locks held by swapper/0:
[ 358.300038] #0: (&port_lock_key){-.-...}, at: [<801df9ec>] imx_rxint+0x24/0x2a4
[ 358.307669] #1: (sysrq_key_table_lock){-.....}, at: [<801cda7c>] __handle_sysrq+0x1c/0x188
[ 358.316253] Modules linked in:
[ 358.319337] Backtrace:
[ 358.321837] [<80010e9c>] (dump_backtrace+0x0/0x10c) from [<80365da0>] (dump_stack+0x18/0x1c)
[ 358.330320] r6:804d8600 r5:80425b9c r4:804d8600 r3:20000113
[ 358.336121] [<80365d88>] (dump_stack+0x0/0x1c) from [<803664cc>] (__schedule_bug+0x64/0x78)
[ 358.344505] [<80366468>] (__schedule_bug+0x0/0x78) from [<8036acf8>] (__schedule+0x3fc/0x464)
[ 358.353072] r4:804ce000 r3:00000000
[ 358.356752] [<8036a8fc>] (__schedule+0x0/0x464) from [<8004153c>] (__cond_resched+0x28/0x38)
[ 358.365225] [<80041514>] (__cond_resched+0x0/0x38) from [<8036adf4>] (_cond_resched+0x38/0x48)
[ 358.373880] r4:804fb224 r3:00010003
[ 358.377553] [<8036adbc>] (_cond_resched+0x0/0x48) from [<80369d90>] (mutex_lock_nested+0x30/0x2d0)
[ 358.386580] [<80369d60>] (mutex_lock_nested+0x0/0x2d0) from [<8028ffdc>] (clk_get_sys+0x24/0x110)
[ 358.395492] [<8028ffb8>] (clk_get_sys+0x0/0x110) from [<800188c8>] (mxc_restart+0x18/0xb8)
[ 358.403824] [<800188b0>] (mxc_restart+0x0/0xb8) from [<8000ed70>] (machine_restart+0x24/0x60)
[ 358.412393] r5:804e4d70 r4:804dab3c
[ 358.416046] [<8000ed4c>] (machine_restart+0x0/0x60) from [<8002d554>] (emergency_restart+0x1c/0x20)
[ 358.425135] r5:00000062 r4:804dab3c
[ 358.428810] [<8002d538>] (emergency_restart+0x0/0x20) from [<801cd93c>] (sysrq_handle_reboot+0x1c/0x20)
[ 358.438265] [<801cd920>] (sysrq_handle_reboot+0x0/0x20) from [<801cdb6c>] (__handle_sysrq+0x10c/0x188)
[ 358.447631] [<801cda60>] (__handle_sysrq+0x0/0x188) from [<801cde00>] (handle_sysrq+0x30/0x38)
[ 358.456308] [<801cddd0>] (handle_sysrq+0x0/0x38) from [<801dfba8>] (imx_rxint+0x1e0/0x2a4)
[ 358.464604] [<801df9c8>] (imx_rxint+0x0/0x2a4) from [<801e0b0c>] (imx_int+0xa0/0xb8)
[ 358.472410] [<801e0a6c>] (imx_int+0x0/0xb8) from [<80063f44>] (handle_irq_event_percpu+0x54/0x1bc)
[ 358.481411] r6:00000000 r5:87808e90 r4:870e9000 r3:801e0a6c
[ 358.487210] [<80063ef0>] (handle_irq_event_percpu+0x0/0x1bc) from [<800640f0>] (handle_irq_event+0x44/0x64)
[ 358.497013] [<800640ac>] (handle_irq_event+0x0/0x64) from [<80066414>] (handle_level_irq+0x94/0xf0)
[ 358.506072] r6:00000000 r5:87808e90 r4:87808e40 r3:00020000
[ 358.511877] [<80066380>] (handle_level_irq+0x0/0xf0) from [<800637a8>] (generic_handle_irq+0x28/0x38)
[ 358.521139] r5:0000003d r4:0000003d
[ 358.524787] [<80063780>] (generic_handle_irq+0x0/0x38) from [<8000e92c>] (handle_IRQ+0x38/0x8c)
[ 358.533529] r4:804e4da4 r3:000000b4
[ 358.537199] [<8000e8f4>] (handle_IRQ+0x0/0x8c) from [<800084c4>] (avic_handle_irq+0x3c/0x5c)
[ 358.545650] r6:0000ffff r5:804cff18 r4:80502e58 r3:00000010
[ 358.551450] [<80008488>] (avic_handle_irq+0x0/0x5c) from [<8000dd24>] (__irq_svc+0x44/0x58)
[ 358.559847] Exception stack(0x804cff18 to 0x804cff60)
[ 358.564918] ff00: 00000001 00000001
[ 358.573156] ff20: 00000000 804d8600 804ce000 80502a68 804d98d0 804ce000 80004008 4117b363
[ 358.581391] ff40: 804c1cec 804cff6c 804cff30 804cff60 800530e0 8000eaac 20000013 ffffffff
[ 358.589609] r6:ffffffff r5:20000013 r4:8000eaac r3:804d8600
[ 358.595383] [<8000ea84>] (default_idle+0x0/0x40) from [<8000ec88>] (cpu_idle+0x64/0xd0)
[ 358.603455] [<8000ec24>] (cpu_idle+0x0/0xd0) from [<803605a8>] (rest_init+0xc4/0xec)
[ 358.611241] r7:00000002 r6:00000001 r5:804dc534 r4:804ce000
[ 358.617041] [<803604e4>] (rest_init+0x0/0xec) from [<804a27d0>] (start_kernel+0x2ac/0x2fc)
[ 358.625319] r7:80b4e620 r6:804c31bc r5:805029c0 r4:804d6140
[ 358.631118] [<804a2524>] (start_kernel+0x0/0x2fc) from [<80008040>] (0x80008040)
[ 358.686854] ------------[ cut here ]------------
[ 358.691551] WARNING: at kernel/mutex.c:198 mutex_lock_nested+0x290/0x2d0()
[ 358.703020] Modules linked in:
[ 358.706145] Backtrace:
[ 358.708665] [<80010e9c>] (dump_backtrace+0x0/0x10c) from [<80365da0>] (dump_stack+0x18/0x1c)
[ 358.717153] r6:000000c6 r5:80369ff0 r4:00000000 r3:00000000
[ 358.722925] [<80365d88>] (dump_stack+0x0/0x1c) from [<8001b4d0>] (warn_slowpath_common+0x54/0x6c)
[ 358.731860] [<8001b47c>] (warn_slowpath_common+0x0/0x6c) from [<8001b50c>] (warn_slowpath_null+0x24/0x2c)
[ 358.741469] r8:00000000 r7:804d8600 r6:804ce000 r5:8050401c r4:804fb224 r3:00000009
[ 358.749478] [<8001b4e8>] (warn_slowpath_null+0x0/0x2c) from [<80369ff0>] (mutex_lock_nested+0x290/0x2d0)
[ 358.759032] [<80369d60>] (mutex_lock_nested+0x0/0x2d0) from [<8028ffdc>] (clk_get_sys+0x24/0x110)
[ 358.767984] [<8028ffb8>] (clk_get_sys+0x0/0x110) from [<800188c8>] (mxc_restart+0x18/0xb8)
[ 358.776318] [<800188b0>] (mxc_restart+0x0/0xb8) from [<8000ed70>] (machine_restart+0x24/0x60)
[ 358.784858] r5:804e4d70 r4:804dab3c
[ 358.788547] [<8000ed4c>] (machine_restart+0x0/0x60) from [<8002d554>] (emergency_restart+0x1c/0x20)
[ 358.797637] r5:00000062 r4:804dab3c
[ 358.801294] [<8002d538>] (emergency_restart+0x0/0x20) from [<801cd93c>] (sysrq_handle_reboot+0x1c/0x20)
[ 358.810750] [<801cd920>] (sysrq_handle_reboot+0x0/0x20) from [<801cdb6c>] (__handle_sysrq+0x10c/0x188)
[ 358.820115] [<801cda60>] (__handle_sysrq+0x0/0x188) from [<801cde00>] (handle_sysrq+0x30/0x38)
[ 358.828795] [<801cddd0>] (handle_sysrq+0x0/0x38) from [<801dfba8>] (imx_rxint+0x1e0/0x2a4)
[ 358.837123] [<801df9c8>] (imx_rxint+0x0/0x2a4) from [<801e0b0c>] (imx_int+0xa0/0xb8)
[ 358.844909] [<801e0a6c>] (imx_int+0x0/0xb8) from [<80063f44>] (handle_irq_event_percpu+0x54/0x1bc)
[ 358.853909] r6:00000000 r5:87808e90 r4:870e9000 r3:801e0a6c
[ 358.859708] [<80063ef0>] (handle_irq_event_percpu+0x0/0x1bc) from [<800640f0>] (handle_irq_event+0x44/0x64)
[ 358.869513] [<800640ac>] (handle_irq_event+0x0/0x64) from [<80066414>] (handle_level_irq+0x94/0xf0)
[ 358.878602] r6:00000000 r5:87808e90 r4:87808e40 r3:00020000
[ 358.884374] [<80066380>] (handle_level_irq+0x0/0xf0) from [<800637a8>] (generic_handle_irq+0x28/0x38)
[ 358.893635] r5:0000003d r4:0000003d
[ 358.897307] [<80063780>] (generic_handle_irq+0x0/0x38) from [<8000e92c>] (handle_IRQ+0x38/0x8c)
[ 358.906020] r4:804e4da4 r3:000000b4
[ 358.909693] [<8000e8f4>] (handle_IRQ+0x0/0x8c) from [<800084c4>] (avic_handle_irq+0x3c/0x5c)
[ 358.918173] r6:0000ffff r5:804cff18 r4:80502e58 r3:00000010
[ 358.923941] [<80008488>] (avic_handle_irq+0x0/0x5c) from [<8000dd24>] (__irq_svc+0x44/0x58)
[ 358.932339] Exception stack(0x804cff18 to 0x804cff60)
[ 358.937439] ff00: 00000001 00000001
[ 358.945645] ff20: 00000000 804d8600 804ce000 80502a68 804d98d0 804ce000 80004008 4117b363
[ 358.953878] ff40: 804c1cec 804cff6c 804cff30 804cff60 800530e0 8000eaac 20000013 ffffffff
[ 358.962095] r6:ffffffff r5:20000013 r4:8000eaac r3:804d8600
[ 358.967894] [<8000ea84>] (default_idle+0x0/0x40) from [<8000ec88>] (cpu_idle+0x64/0xd0)
[ 358.975943] [<8000ec24>] (cpu_idle+0x0/0xd0) from [<803605a8>] (rest_init+0xc4/0xec)
[ 358.983728] r7:00000002 r6:00000001 r5:804dc534 r4:804ce000
[ 358.989531] [<803604e4>] (rest_init+0x0/0xec) from [<804a27d0>] (start_kernel+0x2ac/0x2fc)
[ 358.997838] r7:80b4e620 r6:804c31bc r5:805029c0 r4:804d6140
[ 359.003606] [<804a2524>] (start_kernel+0x0/0x2fc) from [<80008040>] (0x80008040)
[ 359.011047] ---[ end trace 1ad357144973f17c ]---
[ 359.015715] BUG: sleeping function called from invalid context at kernel/mutex.c:269
[ 359.028025] in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper
[ 359.034479] INFO: lockdep is turned off.
[ 359.038440] Backtrace:
[ 359.040946] [<80010e9c>] (dump_backtrace+0x0/0x10c) from [<80365da0>] (dump_stack+0x18/0x1c)
[ 359.049430] r6:000016d5 r5:804dbc00 r4:804ce000 r3:60000013
[ 359.055216] [<80365d88>] (dump_stack+0x0/0x1c) from [<80040f70>] (__might_sleep+0xe0/0x11c)
[ 359.063635] [<80040e90>] (__might_sleep+0x0/0x11c) from [<80369d8c>] (mutex_lock_nested+0x2c/0x2d0)
[ 359.072726] r6:804e90dc r5:8780db40 r4:804fb274
[ 359.077470] [<80369d60>] (mutex_lock_nested+0x0/0x2d0) from [<80291478>] (clk_prepare+0x20/0x40)
[ 359.086333] [<80291458>] (clk_prepare+0x0/0x40) from [<800188d8>] (mxc_restart+0x28/0xb8)
[ 359.094526] r5:804e4d70 r4:8780db40
[ 359.098207] [<800188b0>] (mxc_restart+0x0/0xb8) from [<8000ed70>] (machine_restart+0x24/0x60)
[ 359.106776] r5:804e4d70 r4:804dab3c
[ 359.110427] [<8000ed4c>] (machine_restart+0x0/0x60) from [<8002d554>] (emergency_restart+0x1c/0x20)
[ 359.119517] r5:00000062 r4:804dab3c
[ 359.123166] [<8002d538>] (emergency_restart+0x0/0x20) from [<801cd93c>] (sysrq_handle_reboot+0x1c/0x20)
[ 359.132621] [<801cd920>] (sysrq_handle_reboot+0x0/0x20) from [<801cdb6c>] (__handle_sysrq+0x10c/0x188)
[ 359.141988] [<801cda60>] (__handle_sysrq+0x0/0x188) from [<801cde00>] (handle_sysrq+0x30/0x38)
[ 359.150664] [<801cddd0>] (handle_sysrq+0x0/0x38) from [<801dfba8>] (imx_rxint+0x1e0/0x2a4)
[ 359.158987] [<801df9c8>] (imx_rxint+0x0/0x2a4) from [<801e0b0c>] (imx_int+0xa0/0xb8)
[ 359.166794] [<801e0a6c>] (imx_int+0x0/0xb8) from [<80063f44>] (handle_irq_event_percpu+0x54/0x1bc)
[ 359.175767] r6:00000000 r5:87808e90 r4:870e9000 r3:801e0a6c
[ 359.181569] [<80063ef0>] (handle_irq_event_percpu+0x0/0x1bc) from [<800640f0>] (handle_irq_event+0x44/0x64)
[ 359.191374] [<800640ac>] (handle_irq_event+0x0/0x64) from [<80066414>] (handle_level_irq+0x94/0xf0)
[ 359.200461] r6:00000000 r5:87808e90 r4:87808e40 r3:00020000
[ 359.206260] [<80066380>] (handle_level_irq+0x0/0xf0) from [<800637a8>] (generic_handle_irq+0x28/0x38)
[ 359.215494] r5:0000003d r4:0000003d
[ 359.219168] [<80063780>] (generic_handle_irq+0x0/0x38) from [<8000e92c>] (handle_IRQ+0x38/0x8c)
[ 359.227911] r4:804e4da4 r3:000000b4
[ 359.231555] [<8000e8f4>] (handle_IRQ+0x0/0x8c) from [<800084c4>] (avic_handle_irq+0x3c/0x5c)
[ 359.240035] r6:0000ffff r5:804cff18 r4:80502e58 r3:00000010
[ 359.245803] [<80008488>] (avic_handle_irq+0x0/0x5c) from [<8000dd24>] (__irq_svc+0x44/0x58)
[ 359.254198] Exception stack(0x804cff18 to 0x804cff60)
[ 359.259296] ff00: 00000001 00000001
[ 359.267530] ff20: 00000000 804d8600 804ce000 80502a68 804d98d0 804ce000 80004008 4117b363
[ 359.275736] ff40: 804c1cec 804cff6c 804cff30 804cff60 800530e0 8000eaac 20000013 ffffffff
[ 359.283951] r6:ffffffff r5:20000013 r4:8000eaac r3:804d8600
[ 359.289748] [<8000ea84>] (default_idle+0x0/0x40) from [<8000ec88>] (cpu_idle+0x64/0xd0)
[ 359.297818] [<8000ec24>] (cpu_idle+0x0/0xd0) from [<803605a8>] (rest_init+0xc4/0xec)
[ 359.305576] r7:00000002 r6:00000001 r5:804dc534 r4:804ce000
[ 359.311380] [<803604e4>] (rest_init+0x0/0xec) from [<804a27d0>] (start_kernel+0x2ac/0x2fc)
[ 359.319688] r7:80b4e620 r6:804c31bc r5:805029c0 r4:804d6140
[ 359.325454] [<804a2524>] (start_kernel+0x0/0x2fc) from [<80008040>] (0x80008040)
[ 359.332899] BUG: scheduling while atomic: swapper/0/0x40010004
[ 359.338769] INFO: lockdep is turned off.
[ 359.342703] Modules linked in:
[ 359.345783] Backtrace:
[ 359.348312] [<80010e9c>] (dump_backtrace+0x0/0x10c) from [<80365da0>] (dump_stack+0x18/0x1c)
[ 359.356797] r6:804d8600 r5:8780db40 r4:804d8600 r3:60000013
[ 359.362567] [<80365d88>] (dump_stack+0x0/0x1c) from [<803664cc>] (__schedule_bug+0x64/0x78)
[ 359.370980] [<80366468>] (__schedule_bug+0x0/0x78) from [<8036acf8>] (__schedule+0x3fc/0x464)
[ 359.379546] r4:804ce000 r3:00000000
[ 359.383201] [<8036a8fc>] (__schedule+0x0/0x464) from [<8004153c>] (__cond_resched+0x28/0x38)
[ 359.391708] [<80041514>] (__cond_resched+0x0/0x38) from [<8036adf4>] (_cond_resched+0x38/0x48)
[ 359.400365] r4:804fb274 r3:00010003
[ 359.404012] [<8036adbc>] (_cond_resched+0x0/0x48) from [<80369d90>] (mutex_lock_nested+0x30/0x2d0)
[ 359.413041] [<80369d60>] (mutex_lock_nested+0x0/0x2d0) from [<80291478>] (clk_prepare+0x20/0x40)
[ 359.421896] [<80291458>] (clk_prepare+0x0/0x40) from [<800188d8>] (mxc_restart+0x28/0xb8)
[ 359.430116] r5:804e4d70 r4:8780db40
[ 359.433767] [<800188b0>] (mxc_restart+0x0/0xb8) from [<8000ed70>] (machine_restart+0x24/0x60)
[ 359.442336] r5:804e4d70 r4:804dab3c
[ 359.445986] [<8000ed4c>] (machine_restart+0x0/0x60) from [<8002d554>] (emergency_restart+0x1c/0x20)
[ 359.455074] r5:00000062 r4:804dab3c
[ 359.458748] [<8002d538>] (emergency_restart+0x0/0x20) from [<801cd93c>] (sysrq_handle_reboot+0x1c/0x20)
[ 359.468202] [<801cd920>] (sysrq_handle_reboot+0x0/0x20) from [<801cdb6c>] (__handle_sysrq+0x10c/0x188)
[ 359.477569] [<801cda60>] (__handle_sysrq+0x0/0x188) from [<801cde00>] (handle_sysrq+0x30/0x38)
[ 359.486242] [<801cddd0>] (handle_sysrq+0x0/0x38) from [<801dfba8>] (imx_rxint+0x1e0/0x2a4)
[ 359.494538] [<801df9c8>] (imx_rxint+0x0/0x2a4) from [<801e0b0c>] (imx_int+0xa0/0xb8)
[ 359.502344] [<801e0a6c>] (imx_int+0x0/0xb8) from [<80063f44>] (handle_irq_event_percpu+0x54/0x1bc)
[ 359.511344] r6:00000000 r5:87808e90 r4:870e9000 r3:801e0a6c
[ 359.517140] [<80063ef0>] (handle_irq_event_percpu+0x0/0x1bc) from [<800640f0>] (handle_irq_event+0x44/0x64)
[ 359.526943] [<800640ac>] (handle_irq_event+0x0/0x64) from [<80066414>] (handle_level_irq+0x94/0xf0)
[ 359.536002] r6:00000000 r5:87808e90 r4:87808e40 r3:00020000
[ 359.541803] [<80066380>] (handle_level_irq+0x0/0xf0) from [<800637a8>] (generic_handle_irq+0x28/0x38)
[ 359.551064] r5:0000003d r4:0000003d
[ 359.554713] [<80063780>] (generic_handle_irq+0x0/0x38) from [<8000e92c>] (handle_IRQ+0x38/0x8c)
[ 359.563453] r4:804e4da4 r3:000000b4
[ 359.567121] [<8000e8f4>] (handle_IRQ+0x0/0x8c) from [<800084c4>] (avic_handle_irq+0x3c/0x5c)
[ 359.575572] r6:0000ffff r5:804cff18 r4:80502e58 r3:00000010
[ 359.581372] [<80008488>] (avic_handle_irq+0x0/0x5c) from [<8000dd24>] (__irq_svc+0x44/0x58)
[ 359.589768] Exception stack(0x804cff18 to 0x804cff60)
[ 359.594839] ff00: 00000001 00000001
[ 359.603073] ff20: 00000000 804d8600 804ce000 80502a68 804d98d0 804ce000 80004008 4117b363
[ 359.611307] ff40: 804c1cec 804cff6c 804cff30 804cff60 800530e0 8000eaac 20000013 ffffffff
[ 359.619524] r6:ffffffff r5:20000013 r4:8000eaac r3:804d8600
[ 359.625296] [<8000ea84>] (default_idle+0x0/0x40) from [<8000ec88>] (cpu_idle+0x64/0xd0)
[ 359.633366] [<8000ec24>] (cpu_idle+0x0/0xd0) from [<803605a8>] (rest_init+0xc4/0xec)
[ 359.641152] r7:00000002 r6:00000001 r5:804dc534 r4:804ce000
[ 359.646950] [<803604e4>] (rest_init+0x0/0xec) from [<804a27d0>] (start_kernel+0x2ac/0x2fc)
[ 359.655227] r7:80b4e620 r6:804c31bc r5:805029c0 r4:804d6140
[ 359.661024] [<804a2524>] (start_kernel+0x0/0x2fc) from [<80008040>] (0x80008040)
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |
^ permalink raw reply [flat|nested] 7+ messages in thread* restart callback not supposed to sleep?
2012-08-20 8:24 restart callback not supposed to sleep? Uwe Kleine-König
@ 2012-08-20 8:57 ` Russell King - ARM Linux
2012-08-20 8:57 ` Lothar Waßmann
1 sibling, 0 replies; 7+ messages in thread
From: Russell King - ARM Linux @ 2012-08-20 8:57 UTC (permalink / raw)
To: linux-arm-kernel
On Mon, Aug 20, 2012 at 10:24:23AM +0200, Uwe Kleine-K?nig wrote:
> while triggering a reboot via sysrq on an ARM machine I saw a "BUG:
> sleeping function called from invalid context" message (details below).
> The reason is that the sysrq handler is calling the restart hook in irq
> context.
Correct - it's been the case for years that the restart hook is called
from atomic contexts (it's not only sysrq, but also softdog as well which
does this, as well as any system panic with panic timeout/panic-on-oops
enabled.)
You need to fix your platform restart hook.
^ permalink raw reply [flat|nested] 7+ messages in thread
* restart callback not supposed to sleep?
2012-08-20 8:24 restart callback not supposed to sleep? Uwe Kleine-König
2012-08-20 8:57 ` Russell King - ARM Linux
@ 2012-08-20 8:57 ` Lothar Waßmann
2012-08-20 9:05 ` Russell King - ARM Linux
1 sibling, 1 reply; 7+ messages in thread
From: Lothar Waßmann @ 2012-08-20 8:57 UTC (permalink / raw)
To: linux-arm-kernel
Hi,
Uwe Kleine-K?nig writes:
> Hello,
>
> while triggering a reboot via sysrq on an ARM machine I saw a "BUG:
> sleeping function called from invalid context" message (details below).
> The reason is that the sysrq handler is calling the restart hook in irq
> context. So what should be done about that? The obvious possiblities
> are:
>
> a) ignore the problem as it won't result in problems (and maybe somehow
> silence the warnign); or
> b) make the restart hook atomic; or
> c) assert sysrq not calling the hook in atomic mode
>
> What do you think?
>
This has been discussed earlier (with your participation) with 'a)'
being the conclusion.
http://lists.infradead.org/pipermail/linux-arm-kernel/2010-December/033877.html
Lothar Wa?mann
--
___________________________________________________________
Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen
Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
Gesch?ftsf?hrer: Matthias Kaussen
Handelsregistereintrag: Amtsgericht Aachen, HRB 4996
www.karo-electronics.de | info at karo-electronics.de
___________________________________________________________
^ permalink raw reply [flat|nested] 7+ messages in thread
* restart callback not supposed to sleep?
2012-08-20 8:57 ` Lothar Waßmann
@ 2012-08-20 9:05 ` Russell King - ARM Linux
2012-08-20 9:21 ` Uwe Kleine-König
0 siblings, 1 reply; 7+ messages in thread
From: Russell King - ARM Linux @ 2012-08-20 9:05 UTC (permalink / raw)
To: linux-arm-kernel
On Mon, Aug 20, 2012 at 10:57:34AM +0200, Lothar Wa?mann wrote:
> Hi,
>
> Uwe Kleine-K?nig writes:
> > Hello,
> >
> > while triggering a reboot via sysrq on an ARM machine I saw a "BUG:
> > sleeping function called from invalid context" message (details below).
> > The reason is that the sysrq handler is calling the restart hook in irq
> > context. So what should be done about that? The obvious possiblities
> > are:
> >
> > a) ignore the problem as it won't result in problems (and maybe somehow
> > silence the warnign); or
> > b) make the restart hook atomic; or
> > c) assert sysrq not calling the hook in atomic mode
> >
> > What do you think?
> >
> This has been discussed earlier (with your participation) with 'a)'
> being the conclusion.
> http://lists.infradead.org/pipermail/linux-arm-kernel/2010-December/033877.html
Except if you look at the backtrace, it seems that it fails to restart.
There are two attempts there at making it restart so the first could
not have succeeded.
^ permalink raw reply [flat|nested] 7+ messages in thread
* restart callback not supposed to sleep?
2012-08-20 9:05 ` Russell King - ARM Linux
@ 2012-08-20 9:21 ` Uwe Kleine-König
2012-08-20 9:44 ` Russell King - ARM Linux
0 siblings, 1 reply; 7+ messages in thread
From: Uwe Kleine-König @ 2012-08-20 9:21 UTC (permalink / raw)
To: linux-arm-kernel
On Mon, Aug 20, 2012 at 10:05:46AM +0100, Russell King - ARM Linux wrote:
> On Mon, Aug 20, 2012 at 10:57:34AM +0200, Lothar Wa?mann wrote:
> > Hi,
> >
> > Uwe Kleine-K?nig writes:
> > > Hello,
> > >
> > > while triggering a reboot via sysrq on an ARM machine I saw a "BUG:
> > > sleeping function called from invalid context" message (details below).
> > > The reason is that the sysrq handler is calling the restart hook in irq
> > > context. So what should be done about that? The obvious possiblities
> > > are:
> > >
> > > a) ignore the problem as it won't result in problems (and maybe somehow
> > > silence the warnign); or
> > > b) make the restart hook atomic; or
> > > c) assert sysrq not calling the hook in atomic mode
> > >
> > > What do you think?
> > >
> > This has been discussed earlier (with your participation) with 'a)'
> > being the conclusion.
> > http://lists.infradead.org/pipermail/linux-arm-kernel/2010-December/033877.html
>
> Except if you look at the backtrace, it seems that it fails to restart.
> There are two attempts there at making it restart so the first could
> not have succeeded.
Just for the log: The restart works ok.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2012-08-20 9:47 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-08-20 8:24 restart callback not supposed to sleep? Uwe Kleine-König
2012-08-20 8:57 ` Russell King - ARM Linux
2012-08-20 8:57 ` Lothar Waßmann
2012-08-20 9:05 ` Russell King - ARM Linux
2012-08-20 9:21 ` Uwe Kleine-König
2012-08-20 9:44 ` Russell King - ARM Linux
2012-08-20 9:47 ` Uwe Kleine-König
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