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: 4431 Comm: syz.0.144 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 : [<813db3a0>] lr : [<813db38c>] psr: 60000013 sp : dff55cb8 ip : dff55cb8 fp : dff55cd4 r10: 00000001 r9 : 00000000 r8 : 00000084 r7 : 00000005 r6 : 0000009b r5 : 83e7eb40 r4 : 00000008 r3 : 0000009b r2 : fee00008 r1 : 00000001 r0 : 83e7eb40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84c7a300 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83e7eb40 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 83e7eb40 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 0xdff54000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdff54000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.144 (pid: 4431, stack limit = 0xdff54000) Stack: (0xdff55cb8 to 0xdff56000) 5ca0: 813db340 83e7eb40 5cc0: 00000005 00000005 dff55cf4 dff55cd8 813db078 813db34c 00000005 8050a310 5ce0: 856a8084 856a8084 dff55d14 dff55cf8 813db438 813db02c 856a8084 83e7eb40 5d00: dff55da8 00000005 dff55d54 dff55d18 813db62c 813db3b8 82af1fe0 83818900 5d20: 828215f0 00000000 00000000 829d238c 83e7eb40 83e7eb84 dff55d90 83e7eb40 5d40: 00000000 82b25910 dff55d8c dff55d58 813ca528 813db57c 200000c0 00000000 5d60: dff55d7c 200000c0 83e7eb40 b5403587 200000c0 83b54800 40946400 00000003 5d80: dff55e4c dff55d90 813c6074 813ca42c 35353238 00000000 00000000 00000000 5da0: 00000000 40404f26 00000005 00000002 0000d5db 0000000c 00000009 00000fff 5dc0: 5c95238c 0000000a 000003bf 00000802 00001600 00000005 20000001 00000809 5de0: 0400e1c8 00000006 00000007 00000006 00000199 00000006 00000004 0000000b 5e00: 00000402 00000010 00000003 000000ef 00000000 0000000a 08000003 dffffffd 5e20: 00000000 ee507d88 00000000 8486c3c0 83e7eb40 200000c0 200000c0 83b54800 5e40: dff55f14 dff55e50 813c7040 813c5f80 00000000 00000000 00000000 ee507d88 5e60: 00000000 00000000 824625b4 0000005f 83ca2058 83e7eb70 8427709c 83b54800 5e80: dff55ee4 dff55e90 807a755c 8079d954 00000064 00000001 00000000 dff55eac 5ea0: 8591fd90 834ddcc0 00006400 0000000b dff55ea0 00000000 00000000 ee507d88 5ec0: 8486c3c0 40946400 200000c0 200000c0 8486c3c0 00000003 dff55ef4 dff55ee8 5ee0: 807a767c ee507d88 dff55f14 40946400 00000000 8486c3c1 200000c0 8486c3c0 5f00: 00000003 83b54800 dff55fa4 dff55f18 80578798 813c6a70 ecac8b10 83b54800 5f20: dff55f3c dff55f30 81a606d8 81a605a8 dff55f54 dff55f40 8025c484 8028d914 5f40: dff55fb0 40000000 dff55f84 dff55f58 802229ec 8025c440 00000000 8281cfb4 5f60: dff55fb0 0014ca70 ecac8b10 80222940 00000000 ee507d88 dff55fac 00000000 5f80: 00000000 00316308 00000036 8020029c 83b54800 00000036 00000000 dff55fa8 5fa0: 80200060 80578674 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76faa0bc 5fe0: 76fa9ec0 76fa9eb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813db340>] (subdev_8255_io) from [<813db078>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000005 r6:00000005 r5:83e7eb40 r4:813db340 [<813db020>] (subdev_8255_do_config) from [<813db438>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db020>] (subdev_8255_do_config) from [<813db438>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:856a8084 [<813db3ac>] (subdev_8255_io_init) from [<813db62c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db3ac>] (subdev_8255_io_init) from [<813db62c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000005 r6:dff55da8 r5:83e7eb40 r4:856a8084 [<813db570>] (dev_8255_attach) from [<813ca528>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:83e7eb40 r7:dff55d90 r6:83e7eb84 r5:83e7eb40 r4:829d238c [<813ca420>] (comedi_device_attach) from [<813c6074>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83b54800 r7:200000c0 r6:b5403587 r5:83e7eb40 r4:200000c0 [<813c5f74>] (do_devconfig_ioctl) from [<813c7040>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83b54800 r7:200000c0 r6:200000c0 r5:83e7eb40 r4:8486c3c0 [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83b54800 r9:00000003 r8:8486c3c0 r7:200000c0 r6:8486c3c1 r5:00000000 r4:40946400 [<80578668>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdff55fa8 to 0xdff55ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76faa0bc 5fe0: 76fa9ec0 76fa9eb0 000195a4 00132510 r10:00000036 r9:83b54800 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