> From: Dexuan-Linux Cui <dexuan.linux@xxxxxxxxx> > Sent: Monday, September 2, 2019 10:22 PM > To: Qian Cai <cai@xxxxxx> > Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>; linux-fsdevel@xxxxxxxxxxxxxxx; LKML > <linux-kernel@xxxxxxxxxxxxxxx>; Dexuan Cui <decui@xxxxxxxxxxxxx>; Lili Deng > (Wicresoft North America Ltd) <v-lide@xxxxxxxxxxxxx> > Subject: Re: "fs/namei.c: keep track of nd->root refcount status" causes boot > panic > > On Mon, Sep 2, 2019 at 9:22 PM Qian Cai <cai@xxxxxx> wrote: > > > > The linux-next commit "fs/namei.c: keep track of nd->root refcount status” > [1] causes boot panic on all > > architectures here on today’s linux-next (0902). Reverted it will fix the issue. > > I believe I'm seeing the same issue with next-20190902 in a Linux VM > running on Hyper-V (next-20190830 is good). > > git-bisect points to the same commit in linux-next: > e013ec23b823 ("fs/namei.c: keep track of nd->root refcount status") > > I can reproduce the issue every time I reboot the system. > > Thanks, > Dexuan BTW, I tried the patch https://lkml.org/lkml/2019/8/31/158 -- not helpful at all. FYI: this is my call-trace: [ 16.843452] Run /init as init process Loading, please wait... starting version 239 [ 16.936476] ------------[ cut here ]------------ [ 16.937929] DEBUG_LOCKS_WARN_ON(!test_bit(class_idx, lock_classes_in_use)) [ 16.937929] WARNING: CPU: 10 PID: 366 at kernel/locking/lockdep.c:3850 __lock_acquire.isra.34+0x50c/0x560 [ 16.937929] Modules linked in: [ 16.937929] CPU: 10 PID: 366 Comm: udevadm Not tainted 5.3.0-rc1+ #26 [ 16.937929] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090008 12/07/2018 [ 16.937929] RIP: 0010:__lock_acquire.isra.34+0x50c/0x560 [ 16.937929] Code: 00 85 c0 0f 84 72 fe ff ff 8b 1d af 5b 2b 01 85 db 0f 85 64 fe ff ff 48 c7 c6 08 97 07... [ 16.937929] RSP: 0018:ffffc90003ff3c40 EFLAGS: 00010086 [ 16.937929] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 16.937929] RDX: ffffffff810e3d63 RSI: 0000000000000001 RDI: ffffffff822628a0 [ 16.937929] RBP: 0000000000000000 R08: ffffffff82c0e420 R09: 0000000000039440 [ 16.937929] R10: 0000001209f646b6 R11: 000000000000016e R12: ffff888276440040 [ 16.937929] R13: 0000000000000000 R14: 0000000000000000 R15: ffff888276440818 [ 16.937929] FS: 00007f4ee2f0f8c0(0000) GS:ffff88827d700000(0000) knlGS:0000000000000000 [ 16.937929] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 16.937929] CR2: 000055dce7403000 CR3: 0000000276772003 CR4: 00000000003606e0 [ 16.937929] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 16.937929] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 16.937929] Call Trace: [ 16.937929] lock_acquire+0xae/0x160 [ 16.937929] ? dput.part.34+0x164/0x380 [ 16.937929] ? dput.part.34+0x29/0x380 [ 16.937929] _raw_spin_lock+0x2c/0x40 [ 16.937929] ? dput.part.34+0x164/0x380 [ 16.937929] dput.part.34+0x164/0x380 [ 17.098529] terminate_walk+0xde/0x100 [ 17.098529] path_lookupat.isra.62+0xa3/0x220 [ 17.098529] filename_lookup.part.77+0xa0/0x170 [ 17.098529] ? kmem_cache_alloc+0x169/0x2a0 [ 17.098529] do_readlinkat+0x5d/0x110 [ 17.098529] __x64_sys_readlinkat+0x1a/0x20 [ 17.098529] do_syscall_64+0x5d/0x1c0 [ 17.098529] ? prepare_exit_to_usermode+0x7b/0xb0 [ 17.098529] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 17.098529] RIP: 0033:0x7f4ee378da4a [ 17.098529] Code: 48 8b 0d 49 84 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 ... [ 17.098529] RSP: 002b:00007fffbddb7968 EFLAGS: 00000202 ORIG_RAX: 000000000000010b [ 17.098529] RAX: ffffffffffffffda RBX: 000055dce740b220 RCX: 00007f4ee378da4a [ 17.098529] RDX: 000055dce740b220 RSI: 000055dce740b201 RDI: 0000000000000005 [ 17.098529] RBP: 0000000000000064 R08: 000055dce73fa010 R09: 0000000000000000 [ 17.098529] R10: 0000000000000063 R11: 0000000000000202 R12: 000055dce740b201 [ 17.098529] R13: 0000000000000005 R14: 00007fffbddb79f8 R15: 0000000000000063 [ 17.098529] ---[ end trace 6af6f6ebcc3937e8 ]--- It looks the aforementioned patch causes a memory corruption. If I revert the patch, everything will be back to normal. Thanks, Dexuan