comedi comedi3: 8255: I/O port conflict (0x404f26,4) 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: 9395 Comm: syz.0.1587 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 : [<813dbc30>] lr : [<813dbc1c>] psr: 60000013 sp : df96dcb8 ip : df96dcb8 fp : df96dcd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 8402db40 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 8402db40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84816780 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8402db40 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 8402db40 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 0xdf96c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf96c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.1587 (pid: 9395, stack limit = 0xdf96c000) Stack: (0xdf96dcb8 to 0xdf96e000) dca0: 813dbbd0 8402db40 dcc0: 00000005 00000005 df96dcf4 df96dcd8 813db908 813dbbdc 00000005 8050a7fc dce0: 84e0c084 84e0c084 df96dd14 df96dcf8 813dbcc8 813db8bc 84e0c084 8402db40 dd00: df96dda8 00000005 df96dd54 df96dd18 813dbebc 813dbc48 82af1fe0 83b24480 dd20: 828215f0 00000000 00000000 829d23cc 8402db40 8402db84 df96dd90 8402db40 dd40: 00000000 82b25910 df96dd8c df96dd58 813cadb4 813dbe0c 200000c0 00000000 dd60: df96dd7c 200000c0 8402db40 b5403587 200000c0 8494ec00 40946400 00000003 dd80: df96de4c df96dd90 813c6900 813cacb8 35353238 00000000 00000000 00000000 dda0: 00000000 00404f26 00000005 00000002 00000401 0000000c 00000cc7 00000fff ddc0: 5c95239c 00000005 000003bf 00000802 00001600 00000001 20000001 00000009 dde0: 0000e1cb 00000006 00000004 00000400 00000195 00000006 00000000 0000000b de00: 00000402 00000009 00000003 00000040 00000005 00000004 08000003 dffffffa de20: 00000000 f7785f57 00000000 848d2180 8402db40 200000c0 200000c0 8494ec00 de40: df96df14 df96de50 813c78cc 813c680c 00000000 00000000 00000000 f7785f57 de60: 00000000 00000000 824625b4 0000005f 83f66250 8402db70 8424487c 8494ec00 de80: df96dee4 df96de90 807a7d9c 8079e194 00000064 00000001 00000000 df96deac dea0: 85913d90 83425990 00006400 0000000b df96dea0 00000000 00000000 f7785f57 dec0: 848d2180 40946400 200000c0 200000c0 848d2180 00000003 df96def4 df96dee8 dee0: 807a7ebc f7785f57 df96df14 40946400 00000000 848d2181 200000c0 848d2180 df00: 00000003 8494ec00 df96dfa4 df96df18 80578f00 813c72fc ecac8b10 8494ec00 df20: df96df3c df96df30 81a61740 81a61610 df96df54 df96df40 8025c484 8028d914 df40: df96dfb0 40000000 df96df84 df96df58 802229ec 8025c440 00000000 8281cfb4 df60: df96dfb0 0014ced0 ecac8b10 80222940 00000000 f7785f57 df96dfac 00000000 df80: 00000000 00316308 00000036 8020029c 8494ec00 00000036 00000000 df96dfa8 dfa0: 80200060 80578ddc 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fe00bc dfe0: 76fdfec0 76fdfeb0 00019294 00132970 60000010 00000003 00000000 00000000 Call trace: [<813dbbd0>] (subdev_8255_io) from [<813db908>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:8402db40 r4:813dbbd0 [<813db8b0>] (subdev_8255_do_config) from [<813dbcc8>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db8b0>] (subdev_8255_do_config) from [<813dbcc8>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84e0c084 [<813dbc3c>] (subdev_8255_io_init) from [<813dbebc>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813dbc3c>] (subdev_8255_io_init) from [<813dbebc>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:df96dda8 r5:8402db40 r4:84e0c084 [<813dbe00>] (dev_8255_attach) from [<813cadb4>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:8402db40 r7:df96dd90 r6:8402db84 r5:8402db40 r4:829d23cc [<813cacac>] (comedi_device_attach) from [<813c6900>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8494ec00 r7:200000c0 r6:b5403587 r5:8402db40 r4:200000c0 [<813c6800>] (do_devconfig_ioctl) from [<813c78cc>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8494ec00 r7:200000c0 r6:200000c0 r5:8402db40 r4:848d2180 [<813c72f0>] (comedi_unlocked_ioctl) from [<80578f00>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c72f0>] (comedi_unlocked_ioctl) from [<80578f00>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c72f0>] (comedi_unlocked_ioctl) from [<80578f00>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c72f0>] (comedi_unlocked_ioctl) from [<80578f00>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8494ec00 r9:00000003 r8:848d2180 r7:200000c0 r6:848d2181 r5:00000000 r4:40946400 [<80578dd0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf96dfa8 to 0xdf96dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fe00bc dfe0: 76fdfec0 76fdfeb0 00019294 00132970 r10:00000036 r9:8494ec00 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