#syz dup: WARNING: suspicious RCU usage in getname_flags On Sat, Apr 03, 2021 at 07:35:16PM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: d19cc4bf Merge tag 'trace-v5.12-rc5' of git://git.kernel.o.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1611e681d00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=78ef1d159159890 > dashboard link: https://syzkaller.appspot.com/bug?extid=7a0c25f9520c969c15f5 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+7a0c25f9520c969c15f5@xxxxxxxxxxxxxxxxxxxxxxxxx > > ============================= > WARNING: suspicious RCU usage > 5.12.0-rc5-syzkaller #0 Not tainted > ----------------------------- > kernel/sched/core.c:8294 Illegal context switch in RCU-bh read-side critical section! > > other info that might help us debug this: > > > rcu_scheduler_active = 2, debug_locks = 0 > 1 lock held by syz-executor.2/10002: > #0: ffff8880129669d8 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] > #0: ffff8880129669d8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x285/0x1210 arch/x86/mm/fault.c:1331 > > stack backtrace: > CPU: 0 PID: 10002 Comm: syz-executor.2 Not tainted 5.12.0-rc5-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:79 [inline] > dump_stack+0x141/0x1d7 lib/dump_stack.c:120 > ___might_sleep+0x229/0x2c0 kernel/sched/core.c:8294 > process_huge_page mm/memory.c:5051 [inline] > clear_huge_page+0x9c/0x560 mm/memory.c:5112 > __do_huge_pmd_anonymous_page mm/huge_memory.c:607 [inline] > do_huge_pmd_anonymous_page+0x60e/0x2570 mm/huge_memory.c:772 > create_huge_pmd mm/memory.c:4189 [inline] > __handle_mm_fault+0x2e59/0x4f70 mm/memory.c:4424 > handle_mm_fault+0x1bc/0x7e0 mm/memory.c:4551 > do_user_addr_fault+0x483/0x1210 arch/x86/mm/fault.c:1390 > handle_page_fault arch/x86/mm/fault.c:1475 [inline] > exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1531 > asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577 > RIP: 0033:0x461b6d > Code: 48 01 d0 eb 0b 0f 1f 84 00 00 00 00 00 48 89 f8 48 83 fa 20 72 49 48 83 fa 40 0f 87 9f 00 00 00 c5 fe 6f 06 c5 fe 6f 4c 16 e0 <c5> fe 7f 07 c5 fe 7f 4c 17 e0 c5 f8 77 c3 48 3b 15 7e 8e 04 01 0f > RSP: 002b:00007fffc28c60c8 EFLAGS: 00010287 > RAX: 0000000020000080 RBX: 0000000000000003 RCX: 0000000000570000 > RDX: 000000000000002b RSI: 0000000000570020 RDI: 0000000020000080 > RBP: 00007fffc28c6188 R08: 0000000000970000 R09: 00007fffc2907090 > R10: 000000000000a8e8 R11: 0000000000000000 R12: 0000000000000001 > R13: 0000000000000000 R14: 000000000056bf60 R15: 0000000000035790 > > > --- > 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@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. >
