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: 2533 Comm: syz.0.8652 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 : [<813db8d0>] lr : [<813db8bc>] psr: 60000013 sp : dfa65cb8 ip : dfa65cb8 fp : dfa65cd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 84055d80 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 84055d80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 862cc980 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84055d80 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 84055d80 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 0xdfa64000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa64000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.8652 (pid: 2533, stack limit = 0xdfa64000) Stack: (0xdfa65cb8 to 0xdfa66000) 5ca0: 813db870 84055d80 5cc0: 00000005 00000005 dfa65cf4 dfa65cd8 813db5a8 813db87c 00000005 8050a8a4 5ce0: 84d1b084 84d1b084 dfa65d14 dfa65cf8 813db968 813db55c 84d1b084 84055d80 5d00: dfa65da8 00000005 dfa65d54 dfa65d18 813dbb5c 813db8e8 829d23cc 84055d80 5d20: 84055dc4 00000000 84055d80 829d23cc 84055d80 84055dc4 dfa65d90 84055d80 5d40: 00000000 82b25910 dfa65d8c dfa65d58 813caa54 813dbaac 200000c0 00000000 5d60: dfa65d7c 200000c0 84055d80 b5403587 200000c0 83b12400 40946400 00000003 5d80: dfa65e4c dfa65d90 813c65a0 813ca958 35353238 00000000 00000000 00000000 5da0: 00000000 40404f26 00000005 00000002 0000d5db 0000000c 00000009 00000fff 5dc0: 5c95238c 0000000a 000003bf 00000006 00001600 00000003 20000001 00000809 5de0: 0400e1c8 00000006 00000007 00000006 0000019c 00000006 00000004 0000000b 5e00: 00000402 00000010 00000003 000000ef 00000000 0000000a 08000003 dffffffd 5e20: 00000000 f6865e9d 00000000 84885e40 84055d80 200000c0 200000c0 83b12400 5e40: dfa65f14 dfa65e50 813c756c 813c64ac 00000000 00000000 00000000 f6865e9d 5e60: 00000000 00000000 824625b4 0000005f 83fdf408 84055db0 84331834 83b12400 5e80: dfa65ee4 dfa65e90 807a7c94 8079e08c 00000064 00000001 00000000 dfa65eac 5ea0: 85888790 83425d48 00006400 0000000b dfa65ea0 00000000 00000000 f6865e9d 5ec0: 84885e40 40946400 200000c0 200000c0 84885e40 00000003 dfa65ef4 dfa65ee8 5ee0: 807a7db4 f6865e9d dfa65f14 40946400 00000000 84885e41 200000c0 84885e40 5f00: 00000003 83b12400 dfa65fa4 dfa65f18 80578eb8 813c6f9c ecac8b10 83b12400 5f20: dfa65f3c dfa65f30 81a61000 81a60ed0 dfa65f54 dfa65f40 8025c484 8028d914 5f40: dfa65fb0 40000000 dfa65f84 dfa65f58 802229ec 8025c440 00000000 8281cfb4 5f60: dfa65fb0 0014ced0 ecac8b10 80222940 00000000 f6865e9d dfa65fac 00000000 5f80: 00000000 00316308 00000036 8020029c 83b12400 00000036 00000000 dfa65fa8 5fa0: 80200060 80578d94 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fa50bc 5fe0: 76fa4ec0 76fa4eb0 00019294 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db870>] (subdev_8255_io) from [<813db5a8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:84055d80 r4:813db870 [<813db550>] (subdev_8255_do_config) from [<813db968>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db550>] (subdev_8255_do_config) from [<813db968>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84d1b084 [<813db8dc>] (subdev_8255_io_init) from [<813dbb5c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db8dc>] (subdev_8255_io_init) from [<813dbb5c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:dfa65da8 r5:84055d80 r4:84d1b084 [<813dbaa0>] (dev_8255_attach) from [<813caa54>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84055d80 r7:dfa65d90 r6:84055dc4 r5:84055d80 r4:829d23cc [<813ca94c>] (comedi_device_attach) from [<813c65a0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83b12400 r7:200000c0 r6:b5403587 r5:84055d80 r4:200000c0 [<813c64a0>] (do_devconfig_ioctl) from [<813c756c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83b12400 r7:200000c0 r6:200000c0 r5:84055d80 r4:84885e40 [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6f90>] (comedi_unlocked_ioctl) from [<80578eb8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83b12400 r9:00000003 r8:84885e40 r7:200000c0 r6:84885e41 r5:00000000 r4:40946400 [<80578d88>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa65fa8 to 0xdfa65ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fa50bc 5fe0: 76fa4ec0 76fa4eb0 00019294 00132970 r10:00000036 r9:83b12400 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