On 25-12-24 12:33 pm, 胡连勤 wrote: > Hello Prashanth K: > >>> Considering that in some extreme cases, when performing the unbinding >>> operation, gserial_disconnect has cleared gser->ioport, which triggers >>> gadget reconfiguration, and then calls gs_read_complete, resulting in >>> access to a null pointer. Therefore, ep is disabled before >>> gserial_disconnect sets port to null to prevent this from happening. >> >> gs_read_complete() gets port from ep->driver_data, and it shouldn't get >> affected if gser->ioport is null as long as port[port_num].port is valid. Am I >> missing something here? > > This description is not very appropriate, thank you very much for your suggestion, I will modify it. Seems like this patch has already accepted applied to Gregs tree. So I think its fine for now, just update new description here. > >>> >>> Call trace: >>> gs_read_complete+0x58/0x240 >>> usb_gadget_giveback_request+0x40/0x160 >>> dwc3_remove_requests+0x170/0x484 >>> dwc3_ep0_out_start+0xb0/0x1d4 >>> __dwc3_gadget_start+0x25c/0x720 >>> kretprobe_trampoline.cfi_jt+0x0/0x8 >>> kretprobe_trampoline.cfi_jt+0x0/0x8 >>> udc_bind_to_driver+0x1d8/0x300 >>> usb_gadget_probe_driver+0xa8/0x1dc >>> gadget_dev_desc_UDC_store+0x13c/0x188 >>> configfs_write_iter+0x160/0x1f4 >>> vfs_write+0x2d0/0x40c >>> ksys_write+0x7c/0xf0 >>> __arm64_sys_write+0x20/0x30 >>> invoke_syscall+0x60/0x150 >>> el0_svc_common+0x8c/0xf8 >>> do_el0_svc+0x28/0xa0 >>> el0_svc+0x24/0x84 >>> > > Thanks Regards, Prashanth K
