8<--- cut here --- Unable to handle kernel paging request at virtual address fee00303 when write [fee00303] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 6806 Comm: syz.5.352 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:99 [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 : [<8149bbd8>] lr : [<8149bbc4>] psr: 60000013 sp : dfb41cb8 ip : dfb41cb8 fp : dfb41cd4 r10: 00000300 r9 : 00000004 r8 : dfb41da4 r7 : 00000000 r6 : 0000009b r5 : 84453480 r4 : 00000303 r3 : 0000009b r2 : fee00303 r1 : 00000001 r0 : 84453480 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8630b440 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84453480 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:1048 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 84453480 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: NULL pointer Register r8 information: 2-page vmalloc region starting at 0xdfb40000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfb40000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Register r12 information: 2-page vmalloc region starting at 0xdfb40000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Process syz.5.352 (pid: 6806, stack limit = 0xdfb40000) Stack: (0xdfb41cb8 to 0xdfb42000) 1ca0: 8149bb78 00000300 1cc0: 84453480 00000000 dfb41cf4 dfb41cd8 8149b8b4 8149bb84 00000300 80545ea0 1ce0: 866f8000 866f8000 dfb41d14 dfb41cf8 8149bc6c 8149b868 84453480 00000000 1d00: 866f8000 00000000 dfb41d54 dfb41d18 8149be1c 8149bbf0 ffffffff 00000004 1d20: 00000000 00000000 84453480 82bd95c0 84453480 00000000 dfb41d90 84453480 1d40: 00000000 82d30df4 dfb41d8c dfb41d58 8148a7c0 8149bdb4 40946400 00000000 1d60: dfb41d7c 20000440 84453480 b5403587 40946400 00000001 00000003 8413c980 1d80: dfb41e4c dfb41d90 81485fc4 8148a6c4 35353238 00000000 00000000 00000000 1da0: 00000000 00000300 00000008 0000fca8 00006432 0000000e 00840006 7ffffffe 1dc0: 00000006 08000006 00000005 feffffff 0000ca8b 00000001 fffffffc 00000002 1de0: 00000003 00000005 0004007a 00000005 00007fff 0000000a 00000344 0eb0cab5 1e00: 00000001 00000085 00000e66 00000001 00000003 0800a6b5 00000000 00000005 1e20: 00000000 b20c4e95 00000000 833d4700 84453480 20000440 40946400 00000001 1e40: dfb41f14 dfb41e50 814872ec 81485f04 00000000 b20c4e95 00000000 00000000 1e60: 8254780c dfb41ea4 0000005f 8480cb68 00000064 844534b0 dfb41ee4 dfb41e88 1e80: 80803694 807f99c4 00000064 00000001 00000000 dfb41ea4 85ca1510 8343aa18 1ea0: 00006400 0000000b dfb41e98 00000000 00000000 b20c4e95 00000000 833d4700 1ec0: 40946400 20000440 20000440 833d4700 00000003 8413c980 dfb41ef4 dfb41ee8 1ee0: 808037c8 b20c4e95 dfb41f14 00000000 833d4701 40946400 20000440 833d4700 1f00: 00000003 8413c980 dfb41fa4 dfb41f18 805ba740 81486fa4 ecac8b10 8413c980 1f20: dfb41f3c dfb41f30 81b52100 81b51fcc dfb41f54 dfb41f40 8025a79c 8028e478 1f40: dfb41fb0 40000000 dfb41f84 dfb41f58 80220bdc 8025a758 00000000 82a1eb0c 1f60: dfb41fb0 0013e9c0 ecac8b10 80220b30 00000000 b20c4e95 dfb41fac 00000000 1f80: 00000000 00346310 00000036 8020029c 8413c980 00000036 00000000 dfb41fa8 1fa0: 80200060 805ba508 00000000 00000000 00000003 40946400 20000440 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f350dc 1fe0: 76f34e88 76f34e78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<8149bb78>] (subdev_8255_io) from [<8149b8b4>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:84453480 r5:00000300 r4:8149bb78 [<8149b85c>] (subdev_8255_do_config) from [<8149bc6c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8149b85c>] (subdev_8255_do_config) from [<8149bc6c>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:866f8000 [<8149bbe4>] (subdev_8255_io_init) from [<8149be1c>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<8149bbe4>] (subdev_8255_io_init) from [<8149be1c>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:866f8000 r5:00000000 r4:84453480 [<8149bda8>] (dev_8255_attach) from [<8148a7c0>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d30df4 r9:00000000 r8:84453480 r7:dfb41d90 r6:00000000 r5:84453480 r4:82bd95c0 [<8148a6b8>] (comedi_device_attach) from [<81485fc4>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:8413c980 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:84453480 r4:20000440 [<81485ef8>] (do_devconfig_ioctl) from [<814872ec>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000440 r5:84453480 r4:833d4700 [<81486f98>] (comedi_unlocked_ioctl) from [<805ba740>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81486f98>] (comedi_unlocked_ioctl) from [<805ba740>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81486f98>] (comedi_unlocked_ioctl) from [<805ba740>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81486f98>] (comedi_unlocked_ioctl) from [<805ba740>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8413c980 r9:00000003 r8:833d4700 r7:20000440 r6:40946400 r5:833d4701 r4:00000000 [<805ba4fc>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb41fa8 to 0xdfb41ff0) 1fa0: 00000000 00000000 00000003 40946400 20000440 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f350dc 1fe0: 76f34e88 76f34e78 00018ebc 00130820 r10:00000036 r9:8413c980 r8:8020029c r7:00000036 r6:00346310 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