comedi comedi3: 8255: I/O port conflict (0x40404f26,4) 8<--- cut here --- Unable to handle kernel paging request at virtual address fee00008 when write [fee00008] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 4455 Comm: syz.7.8149 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] PC is at subdev_8255_io+0x60/0x6c drivers/comedi/drivers/comedi_8255.c:43 LR is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] LR is at subdev_8255_io+0x4c/0x6c drivers/comedi/drivers/comedi_8255.c:43 pc : [<813db598>] lr : [<813db584>] psr: 60000013 sp : dfa2dcb8 ip : dfa2dcb8 fp : dfa2dcd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 8410eb40 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 8410eb40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85256b80 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8410eb40 pointer offset 0 size 192 Register r1 information: non-paged memory Register r2 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 8410eb40 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfa2c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa2c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.7.8149 (pid: 4455, stack limit = 0xdfa2c000) Stack: (0xdfa2dcb8 to 0xdfa2e000) dca0: 813db538 8410eb40 dcc0: 00000005 00000005 dfa2dcf4 dfa2dcd8 813db270 813db544 00000005 8050a430 dce0: 86449084 86449084 dfa2dd14 dfa2dcf8 813db630 813db224 86449084 8410eb40 dd00: dfa2dda8 00000005 dfa2dd54 dfa2dd18 813db824 813db5b0 82af1fe0 84b79f00 dd20: 828215f0 00000000 00000000 829d238c 8410eb40 8410eb84 dfa2dd90 8410eb40 dd40: 00000000 82b25910 dfa2dd8c dfa2dd58 813ca720 813db774 200000c0 00000000 dd60: dfa2dd7c 200000c0 8410eb40 b5403587 200000c0 83adc800 40946400 00000003 dd80: dfa2de4c dfa2dd90 813c626c 813ca624 35353238 00000000 00000000 00000000 dda0: 00000000 40404f26 00000005 00000002 0000d5db 0000000c 00000009 00000fff ddc0: 5c95238c 0000000a 000003bf 00000802 00001600 00000005 20000001 00000809 dde0: 0400e1c8 00000006 00000007 00000006 00000199 00000006 00000004 0000000b de00: 00000402 00000010 00000003 000000ef 00000000 0000000a 08000003 dffffffd de20: 00000000 9fbbc600 00000000 856f6a80 8410eb40 200000c0 200000c0 83adc800 de40: dfa2df14 dfa2de50 813c7238 813c6178 00000000 00000000 00000000 9fbbc600 de60: 00000000 00000000 824625b4 0000005f 83d78838 8410eb70 8427fa74 83adc800 de80: dfa2dee4 dfa2de90 807a7684 8079da7c 00000064 00000001 00000000 dfa2deac dea0: 8612c9d0 8342d908 00006400 0000000b dfa2dea0 00000000 00000000 9fbbc600 dec0: 856f6a80 40946400 200000c0 200000c0 856f6a80 00000003 dfa2def4 dfa2dee8 dee0: 807a77a4 9fbbc600 dfa2df14 40946400 00000000 856f6a81 200000c0 856f6a80 df00: 00000003 83adc800 dfa2dfa4 dfa2df18 805788b8 813c6c68 ecac8b10 83adc800 df20: dfa2df3c dfa2df30 81a60ab8 81a60988 dfa2df54 dfa2df40 8025c484 8028d914 df40: dfa2dfb0 40000000 dfa2df84 dfa2df58 802229ec 8025c440 00000000 8281cfb4 df60: dfa2dfb0 0014ca70 ecac8b10 80222940 00000000 9fbbc600 dfa2dfac 00000000 df80: 00000000 00316308 00000036 8020029c 83adc800 00000036 00000000 dfa2dfa8 dfa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f6c0bc dfe0: 76f6bec0 76f6beb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813db538>] (subdev_8255_io) from [<813db270>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:8410eb40 r4:813db538 [<813db218>] (subdev_8255_do_config) from [<813db630>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db218>] (subdev_8255_do_config) from [<813db630>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:86449084 [<813db5a4>] (subdev_8255_io_init) from [<813db824>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db5a4>] (subdev_8255_io_init) from [<813db824>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:dfa2dda8 r5:8410eb40 r4:86449084 [<813db768>] (dev_8255_attach) from [<813ca720>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:8410eb40 r7:dfa2dd90 r6:8410eb84 r5:8410eb40 r4:829d238c [<813ca618>] (comedi_device_attach) from [<813c626c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83adc800 r7:200000c0 r6:b5403587 r5:8410eb40 r4:200000c0 [<813c616c>] (do_devconfig_ioctl) from [<813c7238>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83adc800 r7:200000c0 r6:200000c0 r5:8410eb40 r4:856f6a80 [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83adc800 r9:00000003 r8:856f6a80 r7:200000c0 r6:856f6a81 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa2dfa8 to 0xdfa2dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f6c0bc dfe0: 76f6bec0 76f6beb0 000195a4 00132510 r10:00000036 r9:83adc800 r8:8020029c r7:00000036 r6:00316308 r5:00000000 r4:00000000 Code: e6ef3076 e0842002 e7f32052 e2422612 (e5c23000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef3076 uxtb r3, r6 4: e0842002 add r2, r4, r2 8: e7f32052 ubfx r2, r2, #0, #20 c: e2422612 sub r2, r2, #18874368 @ 0x1200000 * 10: e5c23000 strb r3, [r2] <-- trapping instruction