Hi, Just noticed this in 3.9-rc1 on an iMX28 (ARM) board with a config based on mxs_defconfig. I'm using the patchset "Add tested id switch and vbus connect detect support for Chipidea" from Peter Chen in its 10th version [1], rebased on top of 3.9-rc1, but since this doesn't modify the locks present in the udc_irq function, I think the problem is elsewhere. Please let me know if you have any questions, Thanks, Maxime [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2013-February/151837.html [ 1.893905] ====================================================== [ 1.900097] [ INFO: possible circular locking dependency detected ] [ 1.906381] 3.9.0-rc1-00024-g39231ac #475 Not tainted [ 1.911441] ------------------------------------------------------- [ 1.917716] swapper/0 is trying to acquire lock: [ 1.922341] (&(&ci->lock)->rlock){-.....}, at: [<c02580fc>] ep_enable+0x20/0x25c [ 1.929935] [ 1.929935] but task is already holding lock: [ 1.935782] (&(&cdev->lock)->rlock){-.....}, at: [<c025e46c>] composite_setup+0x384/0xee8 [ 1.944124] [ 1.944124] which lock already depends on the new lock. [ 1.944124] [ 1.952319] [ 1.952319] the existing dependency chain (in reverse order) is: [ 1.959813] -> #1 (&(&cdev->lock)->rlock){-.....}: [ 1.964829] [<c005adb0>] lock_acquire+0x98/0x104 [ 1.970106] [<c0375c28>] _raw_spin_lock_irqsave+0x3c/0x50 [ 1.976152] [<c025d960>] composite_disconnect+0x1c/0x5c [ 1.982016] [<c02591c0>] udc_irq+0x6d8/0xbe8 [ 1.986930] [<c02571fc>] ci_irq+0x9c/0x108 [ 1.991667] [<c0067214>] handle_irq_event_percpu+0x5c/0x268 [ 1.997896] [<c006745c>] handle_irq_event+0x3c/0x5c [ 2.003417] [<c00696c0>] handle_level_irq+0x8c/0xe8 [ 2.008933] [<c0066af4>] generic_handle_irq+0x20/0x30 [ 2.014627] [<c000fb8c>] handle_IRQ+0x30/0x84 [ 2.019633] [<c00086f0>] icoll_handle_irq+0x30/0x44 [ 2.025148] [<c000e8e4>] __irq_svc+0x44/0x54 [ 2.030058] [<c000fd58>] cpu_idle+0x60/0xec [ 2.034884] [<c04e970c>] start_kernel+0x260/0x2a0 [ 2.040237] [<40008040>] 0x40008040 [ 2.044364] -> #0 (&(&ci->lock)->rlock){-.....}: [ 2.049210] [<c005a284>] __lock_acquire+0x14e8/0x1b18 [ 2.054906] [<c005adb0>] lock_acquire+0x98/0x104 [ 2.060164] [<c0375c28>] _raw_spin_lock_irqsave+0x3c/0x50 [ 2.066202] [<c02580fc>] ep_enable+0x20/0x25c [ 2.071207] [<c02629d0>] gether_connect+0x34/0x1c0 [ 2.076643] [<c0262db0>] eem_set_alt+0x70/0xcc [ 2.081723] [<c025eb54>] composite_setup+0xa6c/0xee8 [ 2.087325] [<c0259244>] udc_irq+0x75c/0xbe8 [ 2.092237] [<c02571fc>] ci_irq+0x9c/0x108 [ 2.096973] [<c0067214>] handle_irq_event_percpu+0x5c/0x268 [ 2.103194] [<c006745c>] handle_irq_event+0x3c/0x5c [ 2.108717] [<c00696c0>] handle_level_irq+0x8c/0xe8 [ 2.114234] [<c0066af4>] generic_handle_irq+0x20/0x30 [ 2.119926] [<c000fb8c>] handle_IRQ+0x30/0x84 [ 2.124929] [<c00086f0>] icoll_handle_irq+0x30/0x44 [ 2.130445] [<c000e8e4>] __irq_svc+0x44/0x54 [ 2.135353] [<c000fd58>] cpu_idle+0x60/0xec [ 2.140176] [<c04e970c>] start_kernel+0x260/0x2a0 [ 2.145521] [<40008040>] 0x40008040 [ 2.149645] [ 2.149645] other info that might help us debug this: [ 2.149645] [ 2.157667] Possible unsafe locking scenario: [ 2.157667] [ 2.163598] CPU0 CPU1 [ 2.168134] ---- ---- [ 2.172667] lock(&(&cdev->lock)->rlock); [ 2.176790] lock(&(&ci->lock)->rlock); [ 2.183255] lock(&(&cdev->lock)->rlock); [ 2.189893] lock(&(&ci->lock)->rlock); [ 2.193842] [ 2.193842] *** DEADLOCK *** [ 2.193842] [ 2.199782] 1 lock held by swapper/0: [ 2.203451] #0: (&(&cdev->lock)->rlock){-.....}, at: [<c025e46c>] composite_setup+0x384/0xee8 [ 2.212231] [ 2.212231] stack backtrace: [ 2.216663] [<c0014120>] (unwind_backtrace+0x0/0xf0) from [<c0370078>] (print_circular_bug+0x25c/0x2a8) [ 2.226112] [<c0370078>] (print_circular_bug+0x25c/0x2a8) from [<c005a284>] (__lock_acquire+0x14e8/0x1b18) [ 2.235813] [<c005a284>] (__lock_acquire+0x14e8/0x1b18) from [<c005adb0>] (lock_acquire+0x98/0x104) [ 2.244904] [<c005adb0>] (lock_acquire+0x98/0x104) from [<c0375c28>] (_raw_spin_lock_irqsave+0x3c/0x50) [ 2.254347] [<c0375c28>] (_raw_spin_lock_irqsave+0x3c/0x50) from [<c02580fc>] (ep_enable+0x20/0x25c) [ 2.263527] [<c02580fc>] (ep_enable+0x20/0x25c) from [<c02629d0>] (gether_connect+0x34/0x1c0) [ 2.272094] [<c02629d0>] (gether_connect+0x34/0x1c0) from [<c0262db0>] (eem_set_alt+0x70/0xcc) [ 2.280744] [<c0262db0>] (eem_set_alt+0x70/0xcc) from [<c025eb54>] (composite_setup+0xa6c/0xee8) [ 2.289572] [<c025eb54>] (composite_setup+0xa6c/0xee8) from [<c0259244>] (udc_irq+0x75c/0xbe8) [ 2.298226] [<c0259244>] (udc_irq+0x75c/0xbe8) from [<c02571fc>] (ci_irq+0x9c/0x108) [ 2.306026] [<c02571fc>] (ci_irq+0x9c/0x108) from [<c0067214>] (handle_irq_event_percpu+0x5c/0x268) [ 2.315119] [<c0067214>] (handle_irq_event_percpu+0x5c/0x268) from [<c006745c>] (handle_irq_event+0x3c/0x5c) [ 2.324986] [<c006745c>] (handle_irq_event+0x3c/0x5c) from [<c00696c0>] (handle_level_irq+0x8c/0xe8) [ 2.334159] [<c00696c0>] (handle_level_irq+0x8c/0xe8) from [<c0066af4>] (generic_handle_irq+0x20/0x30) [ 2.343516] [<c0066af4>] (generic_handle_irq+0x20/0x30) from [<c000fb8c>] (handle_IRQ+0x30/0x84) [ 2.352342] [<c000fb8c>] (handle_IRQ+0x30/0x84) from [<c00086f0>] (icoll_handle_irq+0x30/0x44) [ 2.360991] [<c00086f0>] (icoll_handle_irq+0x30/0x44) from [<c000e8e4>] (__irq_svc+0x44/0x54) [ 2.369531] Exception stack(0xc050df68 to 0xc050dfb0) [ 2.374612] df60: 00000001 00000001 00000000 20000013 c050c000 c05476e8 [ 2.382819] df80: c050c000 c050c000 c05476e8 41069265 40504270 00000000 600000d3 c050dfb0 [ 2.391015] dfa0: c005b708 c000fd58 20000013 ffffffff [ 2.396110] [<c000e8e4>] (__irq_svc+0x44/0x54) from [<c000fd58>] (cpu_idle+0x60/0xec) [ 2.403990] [<c000fd58>] (cpu_idle+0x60/0xec) from [<c04e970c>] (start_kernel+0x260/0x2a0) [ 2.412291] [<c04e970c>] (start_kernel+0x260/0x2a0) from [<40008040>] (0x40008040) -- Maxime Ripard, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
