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: 1 UID: 0 PID: 10818 Comm: syz.3.1738 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 : df9d9cb8 ip : df9d9cb8 fp : df9d9cd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 83e48f00 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 83e48f00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85668d40 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83e48f00 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 83e48f00 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 0xdf9d8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf9d8000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.3.1738 (pid: 10818, stack limit = 0xdf9d8000) Stack: (0xdf9d9cb8 to 0xdf9da000) 9ca0: 813db538 83e48f00 9cc0: 00000005 00000005 df9d9cf4 df9d9cd8 813db270 813db544 00000005 8050a430 9ce0: 854f6084 854f6084 df9d9d14 df9d9cf8 813db630 813db224 854f6084 83e48f00 9d00: df9d9da8 00000005 df9d9d54 df9d9d18 813db824 813db5b0 82af1fe0 841f3480 9d20: 828215f0 00000000 00000000 829d238c 83e48f00 83e48f44 df9d9d90 83e48f00 9d40: 00000000 82b25910 df9d9d8c df9d9d58 813ca720 813db774 200000c0 00000000 9d60: df9d9d7c 200000c0 83e48f00 b5403587 200000c0 85ad1800 40946400 00000003 9d80: df9d9e4c df9d9d90 813c626c 813ca624 35353238 00000000 00000000 00000000 9da0: 00000000 40404f26 00000005 00000002 0000d5db 0000000c 00000009 00000fff 9dc0: 5c95238c 0000000a 000003bf 00000802 00001600 00000005 20000001 00000809 9de0: 0400e1c8 00000006 00000007 00000006 00000199 00000006 00000004 0000000b 9e00: 00000402 00000010 00000003 000000ef 00000000 0000000a 08000003 dffffffd 9e20: 00000000 dc4982a0 00000000 86b3c0c0 83e48f00 200000c0 200000c0 85ad1800 9e40: df9d9f14 df9d9e50 813c7238 813c6178 00000000 00000000 00000000 dc4982a0 9e60: 00000000 00000000 824625b4 0000005f 842b8640 83e48f30 83e5fdd4 85ad1800 9e80: df9d9ee4 df9d9e90 807a7684 8079da7c 00000064 00000001 00000000 df9d9eac 9ea0: 86fa2d90 83429bb0 00006400 0000000b df9d9ea0 00000000 00000000 dc4982a0 9ec0: 86b3c0c0 40946400 200000c0 200000c0 86b3c0c0 00000009 df9d9ef4 df9d9ee8 9ee0: 807a77a4 dc4982a0 df9d9f14 40946400 00000000 86b3c0c1 200000c0 86b3c0c0 9f00: 00000009 85ad1800 df9d9fa4 df9d9f18 805788b8 813c6c68 ecac8b10 85ad1800 9f20: df9d9f3c df9d9f30 81a60ab8 81a60988 df9d9f54 df9d9f40 8025c484 8028d914 9f40: df9d9fb0 40000000 df9d9f84 df9d9f58 802229ec 8025c440 00000000 8281cfb4 9f60: df9d9fb0 0014ced0 ecac8b10 80222940 00000000 dc4982a0 df9d9fac 00000000 9f80: 00000000 00316448 00000036 8020029c 85ad1800 00000036 00000000 df9d9fa8 9fa0: 80200060 80578794 00000000 00000000 00000009 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316448 00000036 00300000 00000000 00006364 76f8e0bc 9fe0: 76f8dec0 76f8deb0 0001928c 00132970 60000010 00000009 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 r5:83e48f00 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) r4:854f6084 [<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:df9d9da8 r5:83e48f00 r4:854f6084 [<813db768>] (dev_8255_attach) from [<813ca720>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:83e48f00 r7:df9d9d90 r6:83e48f44 r5:83e48f00 r4:829d238c [<813ca618>] (comedi_device_attach) from [<813c626c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:85ad1800 r7:200000c0 r6:b5403587 r5:83e48f00 r4:200000c0 [<813c616c>] (do_devconfig_ioctl) from [<813c7238>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:85ad1800 r7:200000c0 r6:200000c0 r5:83e48f00 r4:86b3c0c0 [<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) r10:85ad1800 r9:00000009 r8:86b3c0c0 r7:200000c0 r6:86b3c0c1 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9d9fa8 to 0xdf9d9ff0) 9fa0: 00000000 00000000 00000009 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316448 00000036 00300000 00000000 00006364 76f8e0bc 9fe0: 76f8dec0 76f8deb0 0001928c 00132970 r10:00000036 r9:85ad1800 r8:8020029c r7:00000036 r6:00316448 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