Hello,

syzbot found the following issue on:

HEAD commit: 614cb2751d31 Merge tag 'trace-v5.14-rc6' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1462cb61300000 kernel config: https://syzkaller.appspot.com/x/.config?x=96f0602203250753 dashboard link: https://syzkaller.appspot.com/bug?extid=91525b2bd4b5dff71619 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=122bce0e300000

IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+91525b2bd4b5dff71619@syzkaller.appspotmail.com

------------[ cut here ]------------ WARNING: CPU: 0 PID: 11697 at drivers/gpu/drm/drm_gem_shmem_helper.c:562 drm_gem_shmem_vm_open+0x96/0xb0 drivers/gpu/drm/drm_gem_shmem_helper.c:562 Modules linked in: CPU: 0 PID: 11697 Comm: syz-executor.3 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:drm_gem_shmem_vm_open+0x96/0xb0 drivers/gpu/drm/drm_gem_shmem_helper.c:562 Code: 89 c6 e8 7d ec 23 fd 85 db 75 1a e8 34 e5 23 fd 48 89 ef 5b 5d 41 5c e9 e8 61 f5 ff e8 23 e5 23 fd 0f 0b eb ca e8 1a e5 23 fd <0f> 0b eb dd e8 b1 1f 6a fd eb 89 e8 aa 1f 6a fd eb a8 0f 1f 84 00 RSP: 0018:ffffc9000b3cfb90 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 00000000fffffffc RCX: 0000000000000000 RDX: ffff8880364eb880 RSI: ffffffff8451c3e6 RDI: 0000000000000003 RBP: ffff888033c70948 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff8451c3c3 R11: 0000000000000001 R12: ffff888146490800 R13: ffff888033c70a50 R14: 0000000020166000 R15: ffff888033c709d8 FS: 00007fbe43056700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000005422b8 CR3: 0000000036274000 CR4: 0000000000350ef0 Call Trace: __split_vma+0x23c/0x550 mm/mmap.c:2764 __do_munmap+0x32a/0x11c0 mm/mmap.c:2868 do_munmap mm/mmap.c:2922 [inline] munmap_vma_range mm/mmap.c:604 [inline] mmap_region+0x85a/0x1760 mm/mmap.c:1753 do_mmap+0x86e/0x1180 mm/mmap.c:1584 vm_mmap_pgoff+0x1b7/0x290 mm/util.c:519 ksys_mmap_pgoff+0x4a8/0x620 mm/mmap.c:1635 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbe43056188 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 0000000000002000 RDI: 0000000020166000 RBP: 00000000004bfcc4 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000013 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffb615701f R14: 00007fbe43056300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 89 c6 mov %eax,%esi 2: e8 7d ec 23 fd callq 0xfd23ec84 7: 85 db test %ebx,%ebx 9: 75 1a jne 0x25 b: e8 34 e5 23 fd callq 0xfd23e544 10: 48 89 ef mov %rbp,%rdi 13: 5b pop %rbx 14: 5d pop %rbp 15: 41 5c pop %r12 17: e9 e8 61 f5 ff jmpq 0xfff56204 1c: e8 23 e5 23 fd callq 0xfd23e544 21: 0f 0b ud2 23: eb ca jmp 0xffffffef 25: e8 1a e5 23 fd callq 0xfd23e544 2a: 0f 0b ud2 <-- trapping instruction 2c: eb dd jmp 0xb 2e: e8 b1 1f 6a fd callq 0xfd6a1fe4 33: eb 89 jmp 0xffffffbe 35: e8 aa 1f 6a fd callq 0xfd6a1fe4 3a: eb a8 jmp 0xffffffe4 3c: 0f .byte 0xf 3d: 1f (bad) 3e: 84 00 test %al,(%rax)

--- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches