From a3aee3687d4707a96fa49da2914dcced18760c29 Mon Sep 17 00:00:00 2001 From: Peter Chen Date: Wed, 9 Oct 2013 14:39:52 +0800 Subject: usb: chipidea: udc: Fix spinlock recursion during bus reset After configuration, the host also possible sends bus reset at any time, at such situation, it will trigger below spinlock recursion dump. This commit unlocks the spinlock before calling gadget's disconnect. BUG: spinlock recursion on CPU#0, swapper/0/0 lock: 0xbf128014, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.11.0-next-20130910+ #106 [<80014e20>] (unwind_backtrace+0x0/0xec) from [<80011a6c>] (show_stack+0x10/0x14) [<80011a6c>] (show_stack+0x10/0x14) from [<805c143c>] (dump_stack+0x94/0xbc) [<805c143c>] (dump_stack+0x94/0xbc) from [<80282cf8>] (do_raw_spin_lock+0x16c/0x18c) [<80282cf8>] (do_raw_spin_lock+0x16c/0x18c) from [<805c77e0>] (_raw_spin_lock_irqsave+0x50/0x5c) [<805c77e0>] (_raw_spin_lock_irqsave+0x50/0x5c) from [<803cff88>] (ep_disable+0x24/0x110) [<803cff88>] (ep_disable+0x24/0x110) from [<7f015d50>] (gserial_disconnect+0xa0/0x15c [u_serial]) [<7f015d50>] (gserial_disconnect+0xa0/0x15c [u_serial]) from [<7f01c06c>] (acm_disable+0xc/0x30 [usb_f_acm]) [<7f01c06c>] (acm_disable+0xc/0x30 [usb_f_acm]) from [<7f001478>] (reset_config.isra.10+0x34/0x5c [libcomposite]) [<7f001478>] (reset_config.isra.10+0x34/0x5c [libcomposite]) from [<7f0014d4>] (composite_disconnect+0x34/0x5c [libcomposite]) [<7f0014d4>] (composite_disconnect+0x34/0x5c [libcomposite]) from [<803d1024>] (udc_irq+0x770/0xce4) [<803d1024>] (udc_irq+0x770/0xce4) from [<803cdcc0>] (ci_irq+0x98/0x164) [<803cdcc0>] (ci_irq+0x98/0x164) from [<8007edfc>] (handle_irq_event_percpu+0x50/0x17c) [<8007edfc>] (handle_irq_event_percpu+0x50/0x17c) from [<8007ef64>] (handle_irq_event+0x3c/0x5c) [<8007ef64>] (handle_irq_event+0x3c/0x5c) from [<80081e98>] (handle_fasteoi_irq+0x98/0x168) [<80081e98>] (handle_fasteoi_irq+0x98/0x168) from [<8007e598>] (generic_handle_irq+0x28/0x3c) [<8007e598>] (generic_handle_irq+0x28/0x3c) from [<8000edf4>] (handle_IRQ+0x4c/0xb4) [<8000edf4>] (handle_IRQ+0x4c/0xb4) from [<800085bc>] (gic_handle_irq+0x28/0x5c) [<800085bc>] (gic_handle_irq+0x28/0x5c) from [<800125c0>] (__irq_svc+0x40/0x54) Exception stack(0x8083bf68 to 0x8083bfb0) bf60: 81533b80 00000000 00096234 8001d760 8088e12c 00000000 bf80: 8083a000 8083a000 8084290c 805cb414 808428ac 8083a000 00000001 8083bfb0 bfa0: 8000f138 8000f13c 60000013 ffffffff [<800125c0>] (__irq_svc+0x40/0x54) from [<8000f13c>] (arch_cpu_idle+0x30/0x3c) [<8000f13c>] (arch_cpu_idle+0x30/0x3c) from [<8005eb94>] (cpu_startup_entry+0xf4/0x148) [<8005eb94>] (cpu_startup_entry+0xf4/0x148) from [<807f1a2c>] (start_kernel+0x2c4/0x318) BUG: spinlock lockup suspected on CPU#0, swapper/0/0 lock: 0xbf128014, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.11.0-next-20130910+ #106 [<80014e20>] (unwind_backtrace+0x0/0xec) from [<80011a6c>] (show_stack+0x10/0x14) [<80011a6c>] (show_stack+0x10/0x14) from [<805c143c>] (dump_stack+0x94/0xbc) [<805c143c>] (dump_stack+0x94/0xbc) from [<80282c94>] (do_raw_spin_lock+0x108/0x18c) [<80282c94>] (do_raw_spin_lock+0x108/0x18c) from [<805c77e0>] (_raw_spin_lock_irqsave+0x50/0x5c) [<805c77e0>] (_raw_spin_lock_irqsave+0x50/0x5c) from [<803cff88>] (ep_disable+0x24/0x110) [<803cff88>] (ep_disable+0x24/0x110) from [<7f015d50>] (gserial_disconnect+0xa0/0x15c [u_serial]) [<7f015d50>] (gserial_disconnect+0xa0/0x15c [u_serial]) from [<7f01c06c>] (acm_disable+0xc/0x30 [usb_f_acm]) [<7f01c06c>] (acm_disable+0xc/0x30 [usb_f_acm]) from [<7f001478>] (reset_config.isra.10+0x34/0x5c [libcomposite]) [<7f001478>] (reset_config.isra.10+0x34/0x5c [libcomposite]) from [<7f0014d4>] (composite_disconnect+0x34/0x5c [libcomposite]) [<7f0014d4>] (composite_disconnect+0x34/0x5c [libcomposite]) from [<803d1024>] (udc_irq+0x770/0xce4) [<803d1024>] (udc_irq+0x770/0xce4) from [<803cdcc0>] (ci_irq+0x98/0x164) [<803cdcc0>] (ci_irq+0x98/0x164) from [<8007edfc>] (handle_irq_event_percpu+0x50/0x17c) [<8007edfc>] (handle_irq_event_percpu+0x50/0x17c) from [<8007ef64>] (handle_irq_event+0x3c/0x5c) [<8007ef64>] (handle_irq_event+0x3c/0x5c) from [<80081e98>] (handle_fasteoi_irq+0x98/0x168) [<80081e98>] (handle_fasteoi_irq+0x98/0x168) from [<8007e598>] (generic_handle_irq+0x28/0x3c) [<8007e598>] (generic_handle_irq+0x28/0x3c) from [<8000edf4>] (handle_IRQ+0x4c/0xb4) [<8000edf4>] (handle_IRQ+0x4c/0xb4) from [<800085bc>] (gic_handle_irq+0x28/0x5c) [<800085bc>] (gic_handle_irq+0x28/0x5c) from [<800125c0>] (__irq_svc+0x40/0x54) Exception stack(0x8083bf68 to 0x8083bfb0) bf60: 81533b80 00000000 00096234 8001d760 8088e12c 00000000 bf80: 8083a000 8083a000 8084290c 805cb414 808428ac 8083a000 00000001 8083bfb0 bfa0: 8000f138 8000f13c 60000013 ffffffff [<800125c0>] (__irq_svc+0x40/0x54) from [<8000f13c>] (arch_cpu_idle+0x30/0x3c) [<8000f13c>] (arch_cpu_idle+0x30/0x3c) from [<8005eb94>] (cpu_startup_entry+0xf4/0x148) [<8005eb94>] (cpu_startup_entry+0xf4/0x148) from [<807f1a2c>] (start_kernel+0x2c4/0x318) Signed-off-by: Peter Chen Signed-off-by: Greg Kroah-Hartman --- drivers/usb/chipidea/udc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/usb/chipidea/udc.c') diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c index 2bb7d18ef2d5..5c5e9124872f 100644 --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -713,12 +713,12 @@ __acquires(ci->lock) { int retval; + spin_unlock(&ci->lock); if (ci->gadget.speed != USB_SPEED_UNKNOWN) { if (ci->driver) ci->driver->disconnect(&ci->gadget); } - spin_unlock(&ci->lock); retval = _gadget_stop_activity(&ci->gadget); if (retval) goto done; -- cgit v1.2.3