On Tue, Aug 20, 2024 at 09:13:36AM +0000, 胡连勤 wrote: > Hello linux community expert: > > >> Added null pointer check to avoid system crash. > >> > >> Unable to handle kernel NULL pointer dereference at > >> virtual address 00000000000001a8 > >> pc : gs_read_complete+0x58/0x240 > >> lr : usb_gadget_giveback_request+0x40/0x160 > >> sp : ffffffc00f1539c0 > >> x29: ffffffc00f1539c0 x28: ffffff8002a30000 x27: 0000000000000000 > >> x26: ffffff8002a30000 x25: 0000000000000000 x24: ffffff8002a30000 > >> x23: ffffff8002ff9a70 x22: ffffff898e7a7b00 x21: ffffff803c9af9d8 > >> x20: ffffff898e7a7b00 x19: 00000000000001a8 x18: ffffffc0099fd098 > >> x17: 0000000000001000 x16: 0000000080000000 x15: 0000000ac1200000 > >> x14: 0000000000000003 x13: 000000000000d5e8 x12: 0000000355c314ac > >> x11: 0000000000000015 x10: 0000000000000012 x9 : 0000000000000008 > >> x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffffff887cd12000 > >> x5 : 0000000000000002 x4 : ffffffc00f9b07f0 x3 : ffffffc00f1538d0 > >> x2 : 0000000000000001 x1 : 0000000000000000 x0 : 00000000000001a8 > >> 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 > >> el0t_64_sync_handler+0x88/0xec > >> el0t_64_sync+0x1b4/0x1b8 > >> Code: aa1f03e1 aa1303e0 52800022 2a0103e8 (88e87e62) > >> ---[ end trace 938847327a739172 ]--- > >> Kernel panic - not syncing: Oops: Fatal exception > >> > >> Signed-off-by: Lianqin Hu <hulianqin@xxxxxxxx> > >> --- > >> v1: > > - Optimize code comments, delete log printing > > >Also, same comment as before, what: > > - causes port to be NULL > When unbind, the gser_unbind function call gserial_disconnect to set gser->ioport = NULL, and struct gs_port *port = gser->ioport, resulting in port being NULL. > It seems that there is a potential competition between the gs_read_complete function and the gserial_disconnect function. Then fix that properly please.
