8<--- cut here --- Unable to handle kernel paging request at virtual address fee00007 when write [fee00007] *pgd=80000080007003 , *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 18111 Comm: syz.4.3683 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 : [<8145a4d8>] lr : [<8145a4c4>] psr: 60000013 sp : dfd8dcb8 ip : dfd8dcb8 fp : dfd8dcd4 r10: 00000004 r9 : 00000004 r8 : dfd8dda4 r7 : 00000000 r6 : 0000009b r5 : 84717f00 r4 : 00000007 r3 : 0000009b r2 : fee00007 r1 : 00000001 r0 : 84717f00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 86424740 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84717f00 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 84717f00 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 0xdfd8c000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2723 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfd8c000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2723 Register r12 information: 2-page vmalloc region starting at 0xdfd8c000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2723 Process syz.4.3683 (pid: 18111, stack limit = 0xdfd8c000) Stack: (0xdfd8dcb8 to 0xdfd8e000) dca0: 8145a478 00000004 dcc0: 84717f00 00000000 dfd8dcf4 dfd8dcd8 8145a1b4 8145a484 00000004 8052d19c dce0: 85367000 85367000 dfd8dd14 dfd8dcf8 8145a56c 8145a168 84717f00 00000000 dd00: 85367000 00000000 dfd8dd54 dfd8dd18 8145a71c 8145a4f0 ffffffff 00000004 dd20: 82a20600 00000000 00000000 82bd2e5c 84717f00 00000000 dfd8dd90 84717f00 dd40: 00000000 82d2bd44 dfd8dd8c dfd8dd58 814490a4 8145a6b4 40946400 00000000 dd60: dfd8dd7c 200000c0 84717f00 b5403587 40946400 00000003 00000003 84000c40 dd80: dfd8de4c dfd8dd90 814448b0 81448fa8 35353238 00000000 00000000 00000000 dda0: 00000000 00000004 c0002002 00010003 00000008 00008001 fffffff7 00000001 ddc0: 0000569b 00200008 00000406 00000005 fffffffd 00000045 000000ff 00000206 dde0: 000000fe 0000002f 0001a449 00000009 40000003 0000008b 0000cae4 00000000 de00: 20001e58 00000007 00000005 00000005 00000006 00004088 00000000 00000009 de20: 00000000 9f61e1c2 00000000 838aa800 84717f00 200000c0 40946400 00000003 de40: dfd8df14 dfd8de50 81445bd4 814447e8 00000000 9f61e1c2 00000000 00000000 de60: 8252e804 dfd8dea4 0000005f 842972c8 00000064 84717f30 dfd8dee4 dfd8de88 de80: 807ded8c 807d50bc 00000064 00000001 00000000 dfd8dea4 830e8cd0 834e33b8 dea0: 00006400 0000000b dfd8de98 00000000 00000000 9f61e1c2 00000000 838aa800 dec0: 40946400 200000c0 200000c0 838aa800 00000003 84000c40 dfd8def4 dfd8dee8 dee0: 807deec0 9f61e1c2 dfd8df14 00000000 838aa801 40946400 200000c0 838aa800 df00: 00000003 84000c40 dfd8dfa4 dfd8df18 8059c2ac 8144588c ecac8b10 84000c40 df20: dfd8df3c dfd8df30 81b058d4 81b057a0 dfd8df54 dfd8df40 8025a4dc 8028c2bc df40: dfd8dfb0 40000000 dfd8df84 dfd8df58 80220be0 8025a498 00000000 82a1c33c df60: dfd8dfb0 0013e940 ecac8b10 80220b34 00000000 9f61e1c2 dfd8dfac 00000000 df80: 00000000 00346310 00000036 8020029c 84000c40 00000036 00000000 dfd8dfa8 dfa0: 80200060 8059c074 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fdb0dc dfe0: 76fdae88 76fdae78 00018e58 001307a0 60000010 00000003 00000000 00000000 Call trace: [<8145a478>] (subdev_8255_io) from [<8145a1b4>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:84717f00 r5:00000004 r4:8145a478 [<8145a15c>] (subdev_8255_do_config) from [<8145a56c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8145a15c>] (subdev_8255_do_config) from [<8145a56c>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85367000 [<8145a4e4>] (subdev_8255_io_init) from [<8145a71c>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<8145a4e4>] (subdev_8255_io_init) from [<8145a71c>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:85367000 r5:00000000 r4:84717f00 [<8145a6a8>] (dev_8255_attach) from [<814490a4>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d2bd44 r9:00000000 r8:84717f00 r7:dfd8dd90 r6:00000000 r5:84717f00 r4:82bd2e5c [<81448f9c>] (comedi_device_attach) from [<814448b0>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:84000c40 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:84717f00 r4:200000c0 [<814447dc>] (do_devconfig_ioctl) from [<81445bd4>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:200000c0 r5:84717f00 r4:838aa800 [<81445880>] (comedi_unlocked_ioctl) from [<8059c2ac>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81445880>] (comedi_unlocked_ioctl) from [<8059c2ac>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81445880>] (comedi_unlocked_ioctl) from [<8059c2ac>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81445880>] (comedi_unlocked_ioctl) from [<8059c2ac>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:84000c40 r9:00000003 r8:838aa800 r7:200000c0 r6:40946400 r5:838aa801 r4:00000000 [<8059c068>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfd8dfa8 to 0xdfd8dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fdb0dc dfe0: 76fdae88 76fdae78 00018e58 001307a0 r10:00000036 r9:84000c40 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