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: 3854 Comm: syz.0.15 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 : [<813dbdc8>] lr : [<813dbdb4>] psr: 60000013 sp : dfa21cb8 ip : dfa21cb8 fp : dfa21cd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 840c8e40 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 840c8e40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84889840 DAC: 00000000 Register r0 information: slab kmalloc-192 start 840c8e40 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 840c8e40 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 0xdfa20000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa20000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.15 (pid: 3854, stack limit = 0xdfa20000) Stack: (0xdfa21cb8 to 0xdfa22000) 1ca0: 813dbd68 840c8e40 1cc0: 00000005 00000005 dfa21cf4 dfa21cd8 813dbaa0 813dbd74 00000005 8050a85c 1ce0: 8533b084 8533b084 dfa21d14 dfa21cf8 813dbe60 813dba54 8533b084 840c8e40 1d00: dfa21da8 00000005 dfa21d54 dfa21d18 813dc054 813dbde0 82af1fe0 83837200 1d20: 828215f0 00000000 00000000 829d23cc 840c8e40 840c8e84 dfa21d90 840c8e40 1d40: 00000000 82b25910 dfa21d8c dfa21d58 813caf4c 813dbfa4 200000c0 00000000 1d60: dfa21d7c 200000c0 840c8e40 b5403587 200000c0 84b7a400 40946400 00000003 1d80: dfa21e4c dfa21d90 813c6a98 813cae50 35353238 00000000 00000000 00000000 1da0: 00000000 40404f26 00000005 00000001 00000401 00000003 00000009 00001003 1dc0: 00001c82 00000005 000003bb 00000802 00001600 00000005 20000001 00000002 1de0: 0000e1cb 13352f60 00000000 00000400 00000008 00000006 00000005 0000000b 1e00: 00000402 00000009 00000003 00000041 00000005 00000006 08000003 dffffffa 1e20: 00000000 63cda2d3 00000000 85873180 840c8e40 200000c0 200000c0 84b7a400 1e40: dfa21f14 dfa21e50 813c7a64 813c69a4 00000000 00000000 00000000 63cda2d3 1e60: 00000000 00000000 824625b4 0000005f 83e4e058 840c8e70 8427700c 84b7a400 1e80: dfa21ee4 dfa21e90 807a7a88 8079e1d4 00000064 00000001 00000000 dfa21eac 1ea0: 85360550 834dfcc0 00006400 0000000b dfa21ea0 00000000 00000000 63cda2d3 1ec0: 85873180 40946400 200000c0 200000c0 85873180 00000003 dfa21ef4 dfa21ee8 1ee0: 807a7ba8 63cda2d3 dfa21f14 40946400 00000000 85873181 200000c0 85873180 1f00: 00000003 84b7a400 dfa21fa4 dfa21f18 80578f40 813c7494 ecac8b10 84b7a400 1f20: dfa21f3c dfa21f30 81a618c0 81a61790 dfa21f54 dfa21f40 8025c484 8028d914 1f40: dfa21fb0 40000000 dfa21f84 dfa21f58 802229ec 8025c440 00000000 8281cfb4 1f60: dfa21fb0 0014cf70 ecac8b10 80222940 00000000 63cda2d3 dfa21fac 00000000 1f80: 00000000 00316308 00000036 8020029c 84b7a400 00000036 00000000 dfa21fa8 1fa0: 80200060 80578e1c 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f760bc 1fe0: 76f75ec0 76f75eb0 00019294 00132a10 60000010 00000003 00000000 00000000 Call trace: [<813dbd68>] (subdev_8255_io) from [<813dbaa0>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:840c8e40 r4:813dbd68 [<813dba48>] (subdev_8255_do_config) from [<813dbe60>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813dba48>] (subdev_8255_do_config) from [<813dbe60>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8533b084 [<813dbdd4>] (subdev_8255_io_init) from [<813dc054>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813dbdd4>] (subdev_8255_io_init) from [<813dc054>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:dfa21da8 r5:840c8e40 r4:8533b084 [<813dbf98>] (dev_8255_attach) from [<813caf4c>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:840c8e40 r7:dfa21d90 r6:840c8e84 r5:840c8e40 r4:829d23cc [<813cae44>] (comedi_device_attach) from [<813c6a98>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:84b7a400 r7:200000c0 r6:b5403587 r5:840c8e40 r4:200000c0 [<813c6998>] (do_devconfig_ioctl) from [<813c7a64>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:84b7a400 r7:200000c0 r6:200000c0 r5:840c8e40 r4:85873180 [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c7488>] (comedi_unlocked_ioctl) from [<80578f40>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:84b7a400 r9:00000003 r8:85873180 r7:200000c0 r6:85873181 r5:00000000 r4:40946400 [<80578e10>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa21fa8 to 0xdfa21ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f760bc 1fe0: 76f75ec0 76f75eb0 00019294 00132a10 r10:00000036 r9:84b7a400 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