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: 19368 Comm: syz.8.3263 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 : [<813db608>] lr : [<813db5f4>] psr: 60000013 sp : dfc3dcb8 ip : dfc3dcb8 fp : dfc3dcd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 84238000 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 84238000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 87eeba40 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84238000 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 84238000 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 0xdfc3c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfc3c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.8.3263 (pid: 19368, stack limit = 0xdfc3c000) Stack: (0xdfc3dcb8 to 0xdfc3e000) dca0: 813db5a8 84238000 dcc0: 00000005 00000005 dfc3dcf4 dfc3dcd8 813db2e0 813db5b4 00000005 8050a430 dce0: 85f04084 85f04084 dfc3dd14 dfc3dcf8 813db6a0 813db294 85f04084 84238000 dd00: dfc3dda8 00000005 dfc3dd54 dfc3dd18 813db894 813db620 82af1fe0 85718700 dd20: 828215f0 00000000 00000000 829d238c 84238000 84238044 dfc3dd90 84238000 dd40: 00000000 82b25910 dfc3dd8c dfc3dd58 813ca790 813db7e4 200000c0 00000000 dd60: dfc3dd7c 200000c0 84238000 b5403587 200000c0 860f9800 40946400 00000003 dd80: dfc3de4c dfc3dd90 813c62dc 813ca694 35353238 00000000 00000000 00000000 dda0: 00000000 40404f26 00000005 00000002 000f0000 0000000c 00000009 00000fff ddc0: 5c95238c 00000005 000003bf 00000802 00001600 00000005 20000001 00000809 dde0: 0400e1c8 00000006 00000007 00000400 00000195 00000006 00000000 0000000b de00: 00000402 00000000 00000003 000000ef 00000000 0000000a 08000003 dffffffd de20: 00000000 9129e639 00000000 8608a780 84238000 200000c0 200000c0 860f9800 de40: dfc3df14 dfc3de50 813c72a8 813c61e8 00000000 00000000 00000000 9129e639 de60: 00000000 00000000 824625b4 0000005f 8406e058 84238030 84209714 860f9800 de80: dfc3dee4 dfc3de90 807a7684 8079da7c 00000064 00000001 00000000 dfc3deac dea0: 8554b0d0 834e84c8 00006400 0000000b dfc3dea0 00000000 00000000 9129e639 dec0: 8608a780 40946400 200000c0 200000c0 8608a780 00000003 dfc3def4 dfc3dee8 dee0: 807a77a4 9129e639 dfc3df14 40946400 00000000 8608a781 200000c0 8608a780 df00: 00000003 860f9800 dfc3dfa4 dfc3df18 805788b8 813c6cd8 ecac8b10 860f9800 df20: dfc3df3c dfc3df30 81a60b38 81a60a08 dfc3df54 dfc3df40 8025c484 8028d914 df40: dfc3dfb0 40000000 dfc3df84 dfc3df58 802229ec 8025c440 00000000 8281cfb4 df60: dfc3dfb0 0014ced0 ecac8b10 80222940 00000000 9129e639 dfc3dfac 00000000 df80: 00000000 00316308 00000036 8020029c 860f9800 00000036 00000000 dfc3dfa8 dfa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f720bc dfe0: 76f71ec0 76f71eb0 0001928c 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db5a8>] (subdev_8255_io) from [<813db2e0>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:84238000 r4:813db5a8 [<813db288>] (subdev_8255_do_config) from [<813db6a0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db288>] (subdev_8255_do_config) from [<813db6a0>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85f04084 [<813db614>] (subdev_8255_io_init) from [<813db894>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db614>] (subdev_8255_io_init) from [<813db894>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:dfc3dda8 r5:84238000 r4:85f04084 [<813db7d8>] (dev_8255_attach) from [<813ca790>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84238000 r7:dfc3dd90 r6:84238044 r5:84238000 r4:829d238c [<813ca688>] (comedi_device_attach) from [<813c62dc>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:860f9800 r7:200000c0 r6:b5403587 r5:84238000 r4:200000c0 [<813c61dc>] (do_devconfig_ioctl) from [<813c72a8>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:860f9800 r7:200000c0 r6:200000c0 r5:84238000 r4:8608a780 [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:860f9800 r9:00000003 r8:8608a780 r7:200000c0 r6:8608a781 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfc3dfa8 to 0xdfc3dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f720bc dfe0: 76f71ec0 76f71eb0 0001928c 00132970 r10:00000036 r9:860f9800 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