When loading g_ether gadget, there is below message: Backtrace: [<80012248>] (dump_backtrace+0x0/0x10c) from [<803cb42c>] (dump_stack+0x18/0x1c) r7:00000000 r6:80512000 r5:8052bef8 r4:80513f30 [<803cb414>] (dump_stack+0x0/0x1c) from [<8000feb4>] (show_regs+0x44/0x50) [<8000fe70>] (show_regs+0x0/0x50) from [<8004c840>] (__schedule_bug+0x68/0x84) r5:8052bef8 r4:80513f30 [<8004c7d8>] (__schedule_bug+0x0/0x84) from [<803cd0e4>] (__schedule+0x4b0/0x528) r5:8052bef8 r4:809aad00 [<803ccc34>] (__schedule+0x0/0x528) from [<803cd214>] (_cond_resched+0x44/0x58) [<803cd1d0>] (_cond_resched+0x0/0x58) from [<800a9488>] (dma_pool_alloc+0x184/0x250) r5:9f9b4000 r4:9fb4fb80 [<800a9304>] (dma_pool_alloc+0x0/0x250) from [<802a8ad8>] (fsl_req_to_dtd+0xac/0x180) [<802a8a2c>] (fsl_req_to_dtd+0x0/0x180) from [<802a8ce4>] (fsl_ep_queue+0x138/0x274) [<802a8bac>] (fsl_ep_queue+0x0/0x274) from [<7f004328>] (composite_setup+0x2d4/0xfac [g_ether]) [<7f004054>] (composite_setup+0x0/0xfac [g_ether]) from [<802a9bb4>] (fsl_udc_irq+0x8dc/0xd38) [<802a92d8>] (fsl_udc_irq+0x0/0xd38) from [<800704f8>] (handle_irq_event_percpu+0x54/0x188) [<800704a4>] (handle_irq_event_percpu+0x0/0x188) from [<80070674>] (handle_irq_event+0x48/0x68) [<8007062c>] (handle_irq_event+0x0/0x68) from [<800738ec>] (handle_level_irq+0xb4/0x138) r5:80514f94 r4:80514f40 [<80073838>] (handle_level_irq+0x0/0x138) from [<8006ffa4>] (generic_handle_irq+0x38/0x44) r7:00000012 r6:80510b1c r5:80529860 r4:80512000 [<8006ff6c>] (generic_handle_irq+0x0/0x44) from [<8000f4c4>] (handle_IRQ+0x54/0xb4) [<8000f470>] (handle_IRQ+0x0/0xb4) from [<800085b8>] (tzic_handle_irq+0x64/0x94) r9:412fc085 r8:00000000 r7:80513f30 r6:00000001 r5:00000000 r4:00000000 [<80008554>] (tzic_handle_irq+0x0/0x94) from [<8000e680>] (__irq_svc+0x40/0x60) The reason of above dump message is calling dma_poll_alloc with can-schedule mem_flags at interrupt context. Changing mem_flags from GFP_KERNEL to GFP_ATOMIC fix this problem. Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx> --- drivers/usb/gadget/fsl_udc_core.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/usb/gadget/fsl_udc_core.c b/drivers/usb/gadget/fsl_udc_core.c index b04712f..34efcad 100644 --- a/drivers/usb/gadget/fsl_udc_core.c +++ b/drivers/usb/gadget/fsl_udc_core.c @@ -777,7 +777,7 @@ static struct ep_td_struct *fsl_build_dtd(struct fsl_req *req, unsigned *length, *length = min(req->req.length - req->req.actual, (unsigned)EP_MAX_LENGTH_TRANSFER); - dtd = dma_pool_alloc(udc_controller->td_pool, GFP_KERNEL, dma); + dtd = dma_pool_alloc(udc_controller->td_pool, GFP_ATOMIC, dma); if (dtd == NULL) return dtd; -- 1.7.0.4 -- 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
