8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2c when write [fee04f2c] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 20698 Comm: syz.2.5147 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP 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 : [<814162f4>] lr : [<814162e0>] psr: 60000013 sp : df9c1cb0 ip : df9c1cb0 fp : df9c1ccc r10: 00000001 r9 : 00000084 r8 : df9c1d9c r7 : 00004f29 r6 : 0000009b r5 : 844d46c0 r4 : 00004f2c r3 : 0000009b r2 : fee04f2c r1 : 00000001 r0 : 844d46c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 862ccfc0 DAC: 00000000 Register r0 information: slab kmalloc-192 start 844d46c0 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 844d46c0 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xdf9c0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdf9c0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdf9c0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.2.5147 (pid: 20698, stack limit = 0xdf9c0000) Stack: (0xdf9c1cb0 to 0xdf9c2000) 1ca0: 81416294 844d46c0 00004f29 00004f29 1cc0: df9c1cec df9c1cd0 81415fcc 814162a0 00004f29 805150e4 84f98800 84f98800 1ce0: df9c1d0c df9c1cf0 8141638c 81415f80 844d46c0 00000000 84f98800 00004f29 1d00: df9c1d4c df9c1d10 81416538 8141630c 8280cc60 83f39980 828217b0 00000000 1d20: 00000000 829d46a0 844d46c0 844d4704 df9c1d88 844d46c0 00000000 82b28ad8 1d40: df9c1d84 df9c1d50 8140506c 814164d0 844d46f0 00000000 df9c1d74 200000c0 1d60: 844d46c0 b5403587 844d46f0 83313000 40946400 00000003 df9c1e44 df9c1d88 1d80: 814009c4 81404f70 35353238 00000000 00000000 00000000 00000000 00004f29 1da0: 00000005 00000006 00000004 00000001 00000008 fffffffd 00000002 00000081 1dc0: fffffffc 00000002 fffffffe 00000001 00000001 00800061 00000000 00000002 1de0: 00400009 00000009 00000006 00000099 01000000 00000080 00000000 00000007 1e00: 02000e69 00000007 00080004 fffffffe 00000000 fffffff8 00000000 f92ddac1 1e20: 00000000 8629a840 844d46c0 200000c0 844d46f0 83313000 df9c1f14 df9c1e48 1e40: 814019b8 814008d0 00000000 00000000 00000000 00000000 00000000 f92ddac1 1e60: 00000000 00000000 824a45ec 0000005f 840c7018 00000064 8466c09c 83313000 1e80: df9c1ee4 df9c1e90 807b81b8 807ae6dc 00000064 00000001 00000000 df9c1eac 1ea0: 867870d0 834eeb28 00006400 0000000b df9c1ea0 00000000 00000000 f92ddac1 1ec0: 8629a840 40946400 200000c0 200000c0 8629a840 00000003 df9c1ef4 df9c1ee8 1ee0: 807b82d8 f92ddac1 df9c1f14 40946400 00000000 8629a841 200000c0 8629a840 1f00: 00000003 83313000 df9c1fa4 df9c1f18 805857a0 81401408 ecac8b10 83313000 1f20: df9c1f3c df9c1f30 81ab01ec 81ab00bc df9c1f54 df9c1f40 8025bcbc 8028e0c4 1f40: df9c1fb0 40000000 df9c1f84 df9c1f58 80221a38 8025bc78 00000000 8281d17c 1f60: df9c1fb0 0014c8c0 ecac8b10 8022198c 00000000 f92ddac1 df9c1fac 00000000 1f80: 00000000 00326310 00000036 8020029c 83313000 00000036 00000000 df9c1fa8 1fa0: 80200060 8058567c 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fa80bc 1fe0: 76fa7ec0 76fa7eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81416294>] (subdev_8255_io) from [<81415fcc>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f29 r6:00004f29 r5:844d46c0 r4:81416294 [<81415f74>] (subdev_8255_do_config) from [<8141638c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81415f74>] (subdev_8255_do_config) from [<8141638c>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84f98800 [<81416300>] (subdev_8255_io_init) from [<81416538>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81416300>] (subdev_8255_io_init) from [<81416538>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f29 r6:84f98800 r5:00000000 r4:844d46c0 [<814164c4>] (dev_8255_attach) from [<8140506c>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:844d46c0 r7:df9c1d88 r6:844d4704 r5:844d46c0 r4:829d46a0 [<81404f64>] (comedi_device_attach) from [<814009c4>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:83313000 r7:844d46f0 r6:b5403587 r5:844d46c0 r4:200000c0 [<814008c4>] (do_devconfig_ioctl) from [<814019b8>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:83313000 r7:844d46f0 r6:200000c0 r5:844d46c0 r4:8629a840 [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83313000 r9:00000003 r8:8629a840 r7:200000c0 r6:8629a841 r5:00000000 r4:40946400 [<80585670>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9c1fa8 to 0xdf9c1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fa80bc 1fe0: 76fa7ec0 76fa7eb0 000192bc 00132360 r10:00000036 r9:83313000 r8:8020029c r7:00000036 r6:00326310 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