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WARNING: CPU: 0 PID: 20657 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: 20657 Comm: syz-executor.2 Not tainted 5.14.0-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 5d f1 23 fd 85 db 75 1a e8 14 ea 23 fd 48 89 ef 5b 5d 41 5c e9 f8 61 f5 ff e8 03 ea 23 fd 0f 0b eb ca e8 fa e9 23 fd <0f> 0b eb dd e8 31 24 6a fd eb 89 e8 2a 24 6a fd eb a8 0f 1f 84 00
RSP: 0018:ffffc9000202fb90 EFLAGS: 00010212
RAX: 00000000000001e1 RBX: 00000000fffffffc RCX: ffffc9000e0fd000
RDX: 0000000000040000 RSI: ffffffff8451bf66 RDI: 0000000000000003
RBP: ffff8880356a3108 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff8451bf43 R11: 0000000000000000 R12: ffff8881401a7800
R13: ffff88802a5e2210 R14: 0000000020166000 R15: ffff8880356a3198
FS:  00007f758eac5700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000280 CR3: 0000000076b58000 CR4: 0000000000350ee0
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: 0033:0x4665f9
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:00007f758eac5188 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 000000000056c0f0 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000000002000 RDI: 0000000020166000
RBP: 00000000004bfcc4 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000013 R11: 0000000000000246 R12: 000000000056c0f0
R13: 00007ffe5f7452df R14: 00007f758eac5300 R15: 0000000000022000