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: 4877 Comm: syz.0.223 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 : [<813b8568>] lr : [<813b8554>] psr: 60000013 sp : df9edcb8 ip : df9edcb8 fp : df9edcd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 83cfba80 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 83cfba80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8589bfc0 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83cfba80 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 83cfba80 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 0xdf9ec000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdf9ec000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.0.223 (pid: 4877, stack limit = 0xdf9ec000) Stack: (0xdf9edcb8 to 0xdf9ee000) dca0: 813b8508 83cfba80 dcc0: 00000005 00000005 df9edcf4 df9edcd8 813b8240 813b8514 00000005 df9edcf8 dce0: 00000000 84ea4084 df9edd14 df9edcf8 813b8600 813b81f4 84ea4084 83cfba80 dd00: df9edda8 00000005 df9edd54 df9edd18 813b87f4 813b8580 82ae3d60 84023200 dd20: 82821598 00000000 00000000 829d00c4 83cfba80 83cfbac4 df9edd90 83cfba80 dd40: 00000000 82b16f00 df9edd8c df9edd58 813a76f8 813b8744 200000c0 00000000 dd60: df9edd7c 200000c0 83cfba80 b5403587 200000c0 8393b000 40946400 00000003 dd80: df9ede4c df9edd90 813a3278 813a75fc 35353238 00000000 00000000 00000000 dda0: 00000000 40404f26 00000005 fffffffe 00000401 00000800 00000009 00001001 ddc0: fffffff7 00000005 000003bc 00000805 00001600 00000021 00008001 00000005 dde0: 0000e1cb 00000006 0000002f 00000400 00000195 00800006 00000007 0000000b de00: 00080402 0000000d 00000003 00000041 00000001 00000006 08000003 dffffffa de20: 00000000 1ee96156 00000000 856a8480 83cfba80 200000c0 200000c0 8393b000 de40: df9edf14 df9ede50 813a4244 813a3184 00000000 00000000 00000000 1ee96156 de60: 00000000 00000000 8247054c 0000005f 83c9a058 83cfbab0 833d4f3c 8393b000 de80: df9edee4 df9ede90 807979b4 8078dd18 00000064 00000001 00000000 df9edeac dea0: 857ea0d0 834d8e58 00006400 0000000b df9edea0 00000000 00000000 1ee96156 dec0: 856a8480 40946400 200000c0 200000c0 856a8480 00000003 df9edef4 df9edee8 dee0: 80797ad4 1ee96156 df9edf14 40946400 00000000 856a8481 200000c0 856a8480 df00: 00000003 8393b000 df9edfa4 df9edf18 8056cd60 813a3c74 ecac8b10 8393b000 df20: df9edf3c df9edf30 81a394b8 81a39388 df9edf54 df9edf40 8025e490 8028ef64 df40: df9edfb0 40000000 df9edf84 df9edf58 802229ec 8025e44c 00000000 8281cddc df60: df9edfb0 0014c820 ecac8b10 80222940 00000000 1ee96156 df9edfac 00000000 df80: 00000000 002f6308 00000036 8020029c 8393b000 00000036 00000000 df9edfa8 dfa0: 80200060 8056cc3c 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76ff10bc dfe0: 76ff0ec0 76ff0eb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b8508>] (subdev_8255_io) from [<813b8240>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:83cfba80 r4:813b8508 [<813b81e8>] (subdev_8255_do_config) from [<813b8600>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b81e8>] (subdev_8255_do_config) from [<813b8600>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84ea4084 [<813b8574>] (subdev_8255_io_init) from [<813b87f4>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b8574>] (subdev_8255_io_init) from [<813b87f4>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:df9edda8 r5:83cfba80 r4:84ea4084 [<813b8738>] (dev_8255_attach) from [<813a76f8>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r10:82b16f00 r9:00000000 r8:83cfba80 r7:df9edd90 r6:83cfbac4 r5:83cfba80 r4:829d00c4 [<813a75f0>] (comedi_device_attach) from [<813a3278>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8393b000 r7:200000c0 r6:b5403587 r5:83cfba80 r4:200000c0 [<813a3178>] (do_devconfig_ioctl) from [<813a4244>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:8393b000 r7:200000c0 r6:200000c0 r5:83cfba80 r4:856a8480 [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:8393b000 r9:00000003 r8:856a8480 r7:200000c0 r6:856a8481 r5:00000000 r4:40946400 [<8056cc30>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9edfa8 to 0xdf9edff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76ff10bc dfe0: 76ff0ec0 76ff0eb0 0001948c 001322c0 r10:00000036 r9:8393b000 r8:8020029c r7:00000036 r6:002f6308 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