Messages in this thread | | | Date | Thu, 14 Aug 2008 11:21:44 -0700 | From | Max Krasnyansky <> | Subject | Re: [PATCH] cpuset: Rework sched domains and CPU hotplug handling (take 4) |
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Ingo Molnar wrote: > * Ingo Molnar <mingo@elte.hu> wrote: > >> * Paul Jackson <pj@sgi.com> wrote: >> >>> Acked-by: Paul Jackson <pj@sgi.com> >>> >>> ... based on code reading and comparing with the >>> previous version - looks good. Nice work, Max. >>> Thanks. >> applied to tip/sched/cpuset, thanks. (will show up in tip/sched/urgent >> as well soon, for v2.6.27 merging.) > > FYI, this new lockdep warning showed up in -tip testing, after i added > this patch.
Hmm, unless I'm missing something this one is unrelated. There are no cpu hotplug, sched or cpusets paths in the trace besides cpu_maps_update_begin(). But that one is taken in the regular destroy_workqueue() path.
The issues is polldev_mutex and cpu_add_remove_lock nesting. I bet you can trigger that without cpusets. CC'ing Dmitry Torokhov.
btw It seems to be triggered when X closes polled input device. There aren't that many of them $ git grep input_register_polled_device | wc -l 16 What do you have hooked up to the test box ?
Max
> [ 59.750200] ======================================================= > [ 59.750200] [ INFO: possible circular locking dependency detected ] > [ 59.750200] 2.6.27-rc3-tip-00076-g75f9a29-dirty #1 > [ 59.750200] ------------------------------------------------------- > [ 59.750200] Xorg/6623 is trying to acquire lock: > [ 59.750200] (cpu_add_remove_lock){--..}, at: [<c0147dae>] cpu_maps_update_begin+0x14/0x16 > [ 59.750200] > [ 59.750200] but task is already holding lock: > [ 59.750200] (polldev_mutex){--..}, at: [<c07eb66f>] input_close_polled_device+0x22/0x47 > [ 59.750200] > [ 59.750200] which lock already depends on the new lock. > [ 59.750200] > [ 59.750200] > [ 59.750200] the existing dependency chain (in reverse order) is: > [ 59.750200] > [ 59.750200] -> #5 (polldev_mutex){--..}: > [ 59.750200] [<c01632e3>] __lock_acquire+0x848/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c09eaf41>] __mutex_lock_common+0x8a/0x278 > [ 59.750200] [<c09eb15d>] mutex_lock_interruptible_nested+0x2e/0x35 > [ 59.750200] [<c07eb745>] input_open_polled_device+0x1c/0xa3 > [ 59.750200] [<c07e8f84>] input_open_device+0x5a/0x86 > [ 59.750200] [<c07eded0>] evdev_open+0x103/0x14e > [ 59.750200] [<c07ea620>] input_open_file+0x44/0x60 > [ 59.750200] [<c019ff1c>] chrdev_open+0x106/0x11d > [ 59.750200] [<c019c269>] __dentry_open+0x119/0x1f0 > [ 59.750200] [<c019c364>] nameidata_to_filp+0x24/0x38 > [ 59.750200] [<c01a6952>] do_filp_open+0x309/0x5b2 > [ 59.750200] [<c019c04e>] do_sys_open+0x47/0xc1 > [ 59.750200] [<c019c114>] sys_open+0x23/0x2b > [ 59.750200] [<c011bb2f>] sysenter_do_call+0x12/0x43 > [ 59.750200] [<ffffffff>] 0xffffffff > [ 59.750200] > [ 59.750200] -> #4 (&dev->mutex){--..}: > [ 59.750200] [<c01632e3>] __lock_acquire+0x848/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c09eaf41>] __mutex_lock_common+0x8a/0x278 > [ 59.750200] [<c09eb15d>] mutex_lock_interruptible_nested+0x2e/0x35 > [ 59.750200] [<c07ea402>] input_register_handle+0x26/0x80 > [ 59.750200] [<c0424336>] kbd_connect+0x6c/0x95 > [ 59.750200] [<c07e8a46>] input_attach_handler+0x38/0x6b > [ 59.750200] [<c07ea4d7>] input_register_handler+0x7b/0xaf > [ 59.750200] [<c0f63917>] kbd_init+0x6b/0x87 > [ 59.750200] [<c0f63a40>] vty_init+0xd3/0xdc > [ 59.750200] [<c0f63405>] tty_init+0x198/0x19c > [ 59.750200] [<c0101139>] do_one_initcall+0x42/0x133 > [ 59.750200] [<c0f3f610>] kernel_init+0x17b/0x1e2 > [ 59.750200] [<c011c85f>] kernel_thread_helper+0x7/0x10 > [ 59.750200] [<ffffffff>] 0xffffffff > [ 59.750200] > [ 59.750200] -> #3 (input_mutex){--..}: > [ 59.750200] [<c01632e3>] __lock_acquire+0x848/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c09eaf41>] __mutex_lock_common+0x8a/0x278 > [ 59.750200] [<c09eb15d>] mutex_lock_interruptible_nested+0x2e/0x35 > [ 59.750200] [<c07ea2da>] input_register_device+0xff/0x171 > [ 59.750200] [<c04080cd>] acpi_button_add+0x320/0x421 > [ 59.750200] [<c040634f>] acpi_device_probe+0x3f/0x8d > [ 59.750200] [<c048e8fa>] driver_probe_device+0xc3/0x156 > [ 59.750200] [<c048e9cf>] __driver_attach+0x42/0x64 > [ 59.750200] [<c048e22f>] bus_for_each_dev+0x43/0x65 > [ 59.750200] [<c048e713>] driver_attach+0x19/0x1b > [ 59.750200] [<c048dc2d>] bus_add_driver+0xaf/0x1b5 > [ 59.750200] [<c048eb72>] driver_register+0x76/0xd2 > [ 59.750200] [<c040665e>] acpi_bus_register_driver+0x3f/0x41 > [ 59.750200] [<c0f61672>] acpi_button_init+0x37/0x56 > [ 59.750200] [<c0101139>] do_one_initcall+0x42/0x133 > [ 59.750200] [<c0f3f230>] do_async_initcalls+0x1f/0x2f > [ 59.750200] [<c015475f>] run_workqueue+0xb7/0x189 > [ 59.750200] [<c01551ab>] worker_thread+0xbb/0xc7 > [ 59.750200] [<c015764d>] kthread+0x40/0x67 > [ 59.750200] [<c011c85f>] kernel_thread_helper+0x7/0x10 > [ 59.750200] [<ffffffff>] 0xffffffff > [ 59.750200] > [ 59.750200] -> #2 (async_work){--..}: > [ 59.750200] [<c01632e3>] __lock_acquire+0x848/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c015475a>] run_workqueue+0xb2/0x189 > [ 59.750200] [<c01551ab>] worker_thread+0xbb/0xc7 > [ 59.750200] [<c015764d>] kthread+0x40/0x67 > [ 59.750200] [<c011c85f>] kernel_thread_helper+0x7/0x10 > [ 59.750200] [<ffffffff>] 0xffffffff > [ 59.750200] > [ 59.750200] -> #1 (kasyncinit){--..}: > [ 59.750200] [<c01632e3>] __lock_acquire+0x848/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c015499a>] cleanup_workqueue_thread+0x2b/0x5e > [ 59.750200] [<c0154a40>] destroy_workqueue+0x61/0x89 > [ 59.750200] [<c0f3f634>] kernel_init+0x19f/0x1e2 > [ 59.750200] [<c011c85f>] kernel_thread_helper+0x7/0x10 > [ 59.750200] [<ffffffff>] 0xffffffff > [ 59.750200] > [ 59.750200] -> #0 (cpu_add_remove_lock){--..}: > [ 59.750200] [<c01631b4>] __lock_acquire+0x719/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c09eaf41>] __mutex_lock_common+0x8a/0x278 > [ 59.750200] [<c09eb1c7>] mutex_lock_nested+0x2e/0x36 > [ 59.750200] [<c0147dae>] cpu_maps_update_begin+0x14/0x16 > [ 59.750200] [<c0154a05>] destroy_workqueue+0x26/0x89 > [ 59.750200] [<c07eb688>] input_close_polled_device+0x3b/0x47 > [ 59.750200] [<c07e9056>] input_close_device+0x45/0x61 > [ 59.750200] [<c07edd49>] evdev_release+0x7f/0x99 > [ 59.750200] [<c019e7d9>] __fput+0xb3/0x135 > [ 59.750200] [<c019eb5f>] fput+0x1c/0x21 > [ 59.750200] [<c019bffd>] filp_close+0x4c/0x56 > [ 59.750200] [<c019d1d6>] sys_close+0x6d/0xa6 > [ 59.750200] [<c011bb2f>] sysenter_do_call+0x12/0x43 > [ 59.750200] [<ffffffff>] 0xffffffff > [ 59.750200] > [ 59.750200] other info that might help us debug this: > [ 59.750200] > [ 59.750200] 3 locks held by Xorg/6623: > [ 59.750200] #0: (&evdev->mutex){--..}, at: [<c07edd31>] evdev_release+0x67/0x99 > [ 59.750200] #1: (&dev->mutex){--..}, at: [<c07e9030>] input_close_device+0x1f/0x61 > [ 59.750200] #2: (polldev_mutex){--..}, at: [<c07eb66f>] input_close_polled_device+0x22/0x47 > [ 59.750200] > [ 59.750200] stack backtrace: > [ 59.750200] Pid: 6623, comm: Xorg Not tainted 2.6.27-rc3-tip-00076-g75f9a29-dirty #1 > [ 59.750200] [<c016189b>] print_circular_bug_tail+0x5d/0x68 > [ 59.750200] [<c01631b4>] __lock_acquire+0x719/0x9ab > [ 59.750200] [<c01634b6>] lock_acquire+0x70/0x97 > [ 59.750200] [<c0147dae>] ? cpu_maps_update_begin+0x14/0x16 > [ 59.750200] [<c09eaf41>] __mutex_lock_common+0x8a/0x278 > [ 59.750200] [<c0147dae>] ? cpu_maps_update_begin+0x14/0x16 > [ 59.750200] [<c016261e>] ? trace_hardirqs_on_caller+0x94/0xcd > [ 59.750200] [<c09eb1c7>] mutex_lock_nested+0x2e/0x36 > [ 59.750200] [<c0147dae>] ? cpu_maps_update_begin+0x14/0x16 > [ 59.750200] [<c0147dae>] cpu_maps_update_begin+0x14/0x16 > [ 59.750200] [<c0154a05>] destroy_workqueue+0x26/0x89 > [ 59.750200] [<c07eb688>] input_close_polled_device+0x3b/0x47 > [ 59.750200] [<c07e9056>] input_close_device+0x45/0x61 > [ 59.750200] [<c07edd49>] evdev_release+0x7f/0x99 > [ 59.750200] [<c019e7d9>] __fput+0xb3/0x135 > [ 59.750200] [<c019eb5f>] fput+0x1c/0x21 > [ 59.750200] [<c019bffd>] filp_close+0x4c/0x56 > [ 59.750200] [<c019d1d6>] sys_close+0x6d/0xa6 > [ 59.750200] [<c011bb2f>] sysenter_do_call+0x12/0x43 > [ 59.750200] [<c0110000>] ? x86_decode_insn+0x46e/0x942 > [ 59.750200] ======================= > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
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