From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8AB432E03EF; Tue, 7 Oct 2025 13:42:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759844554; cv=none; b=R1mSAZyibuIgMi+mzjLNpFmrxzJl7hInkuzule3akc4Z5kreboTj7Rl9LFjg7E+i3vvM9q3Bc1aDtpkcJh+kBINNxLB+CuMjfZcamfiWI2Z/r7GtIP5S5BnEblj//0bwLm+OfWzQgW/v+9Eh1pY+WvIeLy83YR2mrAY8xlkxg3g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759844554; c=relaxed/simple; bh=YglmNLG9so1bTPsyxotMfL2Qw5hHoTH9HvOhn6Arfic=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References: Content-Type:MIME-Version; b=rXaO/az1eWNvo2FZ5xdqbY7x9y3XK9beRuvo87Nm6tGj0x+G1ys5c+SRHyzKxdtfFnYjBe8kJMZo4PP91cpbsAo7tRXbPb5aBri06poouPBY0dR/3bqG6sRyouC1RwuFiz53QX+7qxyKUd2ZsxsNYrAZ7AwInpCCSG9cW/rzPNc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TjjYNRaD; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TjjYNRaD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B17FCC4CEF1; Tue, 7 Oct 2025 13:42:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1759844554; bh=YglmNLG9so1bTPsyxotMfL2Qw5hHoTH9HvOhn6Arfic=; h=Subject:From:To:Date:In-Reply-To:References:From; b=TjjYNRaDx42dllMuZ259ntYfzVVcmLiXg1eWKLtm+ID5zABsj49fETGleOa0xeEFO 2FgvvklFPGMkdgoxQrvu1g/Ssx64Rbsw/NsUB1QRaIjgS+Y9HKUuzqdC82cxpqonOF 9Cfu5B56e84IQI2+zelwL1mqNMi2rEV2l+jTJxySYn30DtUMcbtm69R4whRh8et/vH 6ML4TFRH0ugfuwgaVtifPohdLLNDKMstksc1VEsMkNDdaC3/Q3wiI7S2rOwfXqaZ3l QtrZ2kELgRxOdR6DZ+QNjuWd5S2+DWopkbD5uitYvxZBsaqkcXy7BK9FQ3F8Ej4RpB xeS2inUVnXzag== Message-ID: <9a0401faa598ddaaf43312008469129fc66776f1.camel@kernel.org> Subject: Re: [syzbot] [nfs?] [io-uring?] WARNING in nfsd_file_cache_init From: Jeff Layton To: syzbot , Dai.Ngo@oracle.com, axboe@kernel.dk, chuck.lever@oracle.com, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, neil@brown.name, okorniev@redhat.com, syzkaller-bugs@googlegroups.com, tom@talpey.com Date: Tue, 07 Oct 2025 09:42:31 -0400 In-Reply-To: <68e4a3d1.a00a0220.298cc0.0471.GAE@google.com> References: <68e4a3d1.a00a0220.298cc0.0471.GAE@google.com> Autocrypt: addr=jlayton@kernel.org; prefer-encrypt=mutual; keydata=mQINBE6V0TwBEADXhJg7s8wFDwBMEvn0qyhAnzFLTOCHooMZyx7XO7dAiIhDSi7G1NPxw n8jdFUQMCR/GlpozMFlSFiZXiObE7sef9rTtM68ukUyZM4pJ9l0KjQNgDJ6Fr342Htkjxu/kFV1Wv egyjnSsFt7EGoDjdKqr1TS9syJYFjagYtvWk/UfHlW09X+jOh4vYtfX7iYSx/NfqV3W1D7EDi0PqV T2h6v8i8YqsATFPwO4nuiTmL6I40ZofxVd+9wdRI4Db8yUNA4ZSP2nqLcLtFjClYRBoJvRWvsv4lm 0OX6MYPtv76hka8lW4mnRmZqqx3UtfHX/hF/zH24Gj7A6sYKYLCU3YrI2Ogiu7/ksKcl7goQjpvtV YrOOI5VGLHge0awt7bhMCTM9KAfPc+xL/ZxAMVWd3NCk5SamL2cE99UWgtvNOIYU8m6EjTLhsj8sn VluJH0/RcxEeFbnSaswVChNSGa7mXJrTR22lRL6ZPjdMgS2Km90haWPRc8Wolcz07Y2se0xpGVLEQ cDEsvv5IMmeMe1/qLZ6NaVkNuL3WOXvxaVT9USW1+/SGipO2IpKJjeDZfehlB/kpfF24+RrK+seQf CBYyUE8QJpvTZyfUHNYldXlrjO6n5MdOempLqWpfOmcGkwnyNRBR46g/jf8KnPRwXs509yAqDB6sE LZH+yWr9LQZEwARAQABtCVKZWZmIExheXRvbiA8amxheXRvbkBwb29jaGllcmVkcy5uZXQ+iQI7BB MBAgAlAhsDBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAUCTpXWPAIZAQAKCRAADmhBGVaCFc65D/4 gBLNMHopQYgG/9RIM3kgFCCQV0pLv0hcg1cjr+bPI5f1PzJoOVi9s0wBDHwp8+vtHgYhM54yt43uI 7Htij0RHFL5eFqoVT4TSfAg2qlvNemJEOY0e4daljjmZM7UtmpGs9NN0r9r50W82eb5Kw5bc/r0km R/arUS2st+ecRsCnwAOj6HiURwIgfDMHGPtSkoPpu3DDp/cjcYUg3HaOJuTjtGHFH963B+f+hyQ2B rQZBBE76ErgTDJ2Db9Ey0kw7VEZ4I2nnVUY9B5dE2pJFVO5HJBMp30fUGKvwaKqYCU2iAKxdmJXRI ONb7dSde8LqZahuunPDMZyMA5+mkQl7kpIpR6kVDIiqmxzRuPeiMP7O2FCUlS2DnJnRVrHmCljLkZ Wf7ZUA22wJpepBligemtSRSbqCyZ3B48zJ8g5B8xLEntPo/NknSJaYRvfEQqGxgk5kkNWMIMDkfQO lDSXZvoxqU9wFH/9jTv1/6p8dHeGM0BsbBLMqQaqnWiVt5mG92E1zkOW69LnoozE6Le+12DsNW7Rj iR5K+27MObjXEYIW7FIvNN/TQ6U1EOsdxwB8o//Yfc3p2QqPr5uS93SDDan5ehH59BnHpguTc27Xi QQZ9EGiieCUx6Zh2ze3X2UW9YNzE15uKwkkuEIj60NvQRmEDfweYfOfPVOueC+iFifbQgSmVmZiBM YXl0b24gPGpsYXl0b25AcmVkaGF0LmNvbT6JAjgEEwECACIFAk6V0q0CGwMGCwkIBwMCBhUIAgkKC wQWAgMBAh4BAheAAAoJEAAOaEEZVoIViKUQALpvsacTMWWOd7SlPFzIYy2/fjvKlfB/Xs4YdNcf9q LqF+lk2RBUHdR/dGwZpvw/OLmnZ8TryDo2zXVJNWEEUFNc7wQpl3i78r6UU/GUY/RQmOgPhs3epQC 3PMJj4xFx+VuVcf/MXgDDdBUHaCTT793hyBeDbQuciARDJAW24Q1RCmjcwWIV/pgrlFa4lAXsmhoa c8UPc82Ijrs6ivlTweFf16VBc4nSLX5FB3ls7S5noRhm5/Zsd4PGPgIHgCZcPgkAnU1S/A/rSqf3F LpU+CbVBDvlVAnOq9gfNF+QiTlOHdZVIe4gEYAU3CUjbleywQqV02BKxPVM0C5/oVjMVx3bri75n1 TkBYGmqAXy9usCkHIsG5CBHmphv9MHmqMZQVsxvCzfnI5IO1+7MoloeeW/lxuyd0pU88dZsV/riHw 87i2GJUJtVlMl5IGBNFpqoNUoqmvRfEMeXhy/kUX4Xc03I1coZIgmwLmCSXwx9MaCPFzV/dOOrju2 xjO+2sYyB5BNtxRqUEyXglpujFZqJxxau7E0eXoYgoY9gtFGsspzFkVNntamVXEWVVgzJJr/EWW0y +jNd54MfPRqH+eCGuqlnNLktSAVz1MvVRY1dxUltSlDZT7P2bUoMorIPu8p7ZCg9dyX1+9T6Muc5d Hxf/BBP/ir+3e8JTFQBFOiLNdFtB9KZWZmIExheXRvbiA8amxheXRvbkBzYW1iYS5vcmc+iQI4BBM BAgAiBQJOldK9AhsDBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAAKCRAADmhBGVaCFWgWD/0ZRi4h N9FK2BdQs9RwNnFZUr7JidAWfCrs37XrA/56olQl3ojn0fQtrP4DbTmCuh0SfMijB24psy1GnkPep naQ6VRf7Dxg/Y8muZELSOtsv2CKt3/02J1BBitrkkqmHyni5fLLYYg6fub0T/8Kwo1qGPdu1hx2BQ RERYtQ/S5d/T0cACdlzi6w8rs5f09hU9Tu4qV1JLKmBTgUWKN969HPRkxiojLQziHVyM/weR5Reu6 FZVNuVBGqBD+sfk/c98VJHjsQhYJijcsmgMb1NohAzwrBKcSGKOWJToGEO/1RkIN8tqGnYNp2G+aR 685D0chgTl1WzPRM6mFG1+n2b2RR95DxumKVpwBwdLPoCkI24JkeDJ7lXSe3uFWISstFGt0HL8Eew P8RuGC8s5h7Ct91HMNQTbjgA+Vi1foWUVXpEintAKgoywaIDlJfTZIl6Ew8ETN/7DLy8bXYgq0Xzh aKg3CnOUuGQV5/nl4OAX/3jocT5Cz/OtAiNYj5mLPeL5z2ZszjoCAH6caqsF2oLyAnLqRgDgR+wTQ T6gMhr2IRsl+cp8gPHBwQ4uZMb+X00c/Amm9VfviT+BI7B66cnC7Zv6Gvmtu2rEjWDGWPqUgccB7h dMKnKDthkA227/82tYoFiFMb/NwtgGrn5n2vwJyKN6SEoygGrNt0SI84y6hEVbQlSmVmZiBMYXl0b 24gPGpsYXl0b25AcHJpbWFyeWRhdGEuY29tPokCOQQTAQIAIwUCU4xmKQIbAwcLCQgHAwIBBhUIAg kKCwQWAgMBAh4BAheAAAoJEAAOaEEZVoIV1H0P/j4OUTwFd7BBbpoSp695qb6HqCzWMuExsp8nZjr uymMaeZbGr3OWMNEXRI1FWNHMtcMHWLP/RaDqCJil28proO+PQ/yPhsr2QqJcW4nr91tBrv/MqItu AXLYlsgXqp4BxLP67bzRJ1Bd2x0bWXurpEXY//VBOLnODqThGEcL7jouwjmnRh9FTKZfBDpFRaEfD FOXIfAkMKBa/c9TQwRpx2DPsl3eFWVCNuNGKeGsirLqCxUg5kWTxEorROppz9oU4HPicL6rRH22Ce 6nOAON2vHvhkUuO3GbffhrcsPD4DaYup4ic+DxWm+DaSSRJ+e1yJvwi6NmQ9P9UAuLG93S2MdNNbo sZ9P8k2mTOVKMc+GooI9Ve/vH8unwitwo7ORMVXhJeU6Q0X7zf3SjwDq2lBhn1DSuTsn2DbsNTiDv qrAaCvbsTsw+SZRwF85eG67eAwouYk+dnKmp1q57LDKMyzysij2oDKbcBlwB/TeX16p8+LxECv51a sjS9TInnipssssUDrHIvoTTXWcz7Y5wIngxDFwT8rPY3EggzLGfK5Zx2Q5S/N0FfmADmKknG/D8qG IcJE574D956tiUDKN4I+/g125ORR1v7bP+OIaayAvq17RP+qcAqkxc0x8iCYVCYDouDyNvWPGRhbL UO7mlBpjW9jK9e2fvZY9iw3QzIPGKtClKZWZmIExheXRvbiA8amVmZi5sYXl0b25AcHJpbWFyeWRh dGEuY29tPokCOQQTAQIAIwUCU4xmUAIbAwcLCQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEAAOa EEZVoIVzJoQALFCS6n/FHQS+hIzHIb56JbokhK0AFqoLVzLKzrnaeXhE5isWcVg0eoV2oTScIwUSU apy94if69tnUo4Q7YNt8/6yFM6hwZAxFjOXR0ciGE3Q+Z1zi49Ox51yjGMQGxlakV9ep4sV/d5a50 M+LFTmYSAFp6HY23JN9PkjVJC4PUv5DYRbOZ6Y1+TfXKBAewMVqtwT1Y+LPlfmI8dbbbuUX/kKZ5d dhV2736fgyfpslvJKYl0YifUOVy4D1G/oSycyHkJG78OvX4JKcf2kKzVvg7/Rnv+AueCfFQ6nGwPn 0P91I7TEOC4XfZ6a1K3uTp4fPPs1Wn75X7K8lzJP/p8lme40uqwAyBjk+IA5VGd+CVRiyJTpGZwA0 jwSYLyXboX+Dqm9pSYzmC9+/AE7lIgpWj+3iNisp1SWtHc4pdtQ5EU2SEz8yKvDbD0lNDbv4ljI7e flPsvN6vOrxz24mCliEco5DwhpaaSnzWnbAPXhQDWb/lUgs/JNk8dtwmvWnqCwRqElMLVisAbJmC0 BhZ/Ab4sph3EaiZfdXKhiQqSGdK4La3OTJOJYZphPdGgnkvDV9Pl1QZ0ijXQrVIy3zd6VCNaKYq7B AKidn5g/2Q8oio9Tf4XfdZ9dtwcB+bwDJFgvvDYaZ5bI3ln4V3EyW5i2NfXazz/GA/I/ZtbsigCFc 8ftCBKZWZmIExheXRvbiA8amxheXRvbkBrZXJuZWwub3JnPokCOAQTAQIAIgUCWe8u6AIbAwYLCQg HAwIGFQgCCQoLBBYCAwECHgECF4AACgkQAA5oQRlWghUuCg/+Lb/xGxZD2Q1oJVAE37uW308UpVSD 2tAMJUvFTdDbfe3zKlPDTuVsyNsALBGclPLagJ5ZTP+Vp2irAN9uwBuacBOTtmOdz4ZN2tdvNgozz uxp4CHBDVzAslUi2idy+xpsp47DWPxYFIRP3M8QG/aNW052LaPc0cedYxp8+9eiVUNpxF4SiU4i9J DfX/sn9XcfoVZIxMpCRE750zvJvcCUz9HojsrMQ1NFc7MFT1z3MOW2/RlzPcog7xvR5ENPH19ojRD CHqumUHRry+RF0lH00clzX/W8OrQJZtoBPXv9ahka/Vp7kEulcBJr1cH5Wz/WprhsIM7U9pse1f1g Yy9YbXtWctUz8uvDR7shsQxAhX3qO7DilMtuGo1v97I/Kx4gXQ52syh/w6EBny71CZrOgD6kJwPVV AaM1LRC28muq91WCFhs/nzHozpbzcheyGtMUI2Ao4K6mnY+3zIuXPygZMFr9KXE6fF7HzKxKuZMJO aEZCiDOq0anx6FmOzs5E6Jqdpo/mtI8beK+BE7Va6ni7YrQlnT0i3vaTVMTiCThbqsB20VrbMjlhp f8lfK1XVNbRq/R7GZ9zHESlsa35ha60yd/j3pu5hT2xyy8krV8vGhHvnJ1XRMJBAB/UYb6FyC7S+m QZIQXVeAA+smfTT0tDrisj1U5x6ZB9b3nBg65kc= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2025-10-06 at 22:23 -0700, syzbot wrote: > Hello, >=20 > syzbot found the following issue on: >=20 > HEAD commit: d104e3d17f7b Merge tag 'cxl-for-6.18' of git://git.kernel= ... > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=3D116bb94258000= 0 > kernel config: https://syzkaller.appspot.com/x/.config?x=3Dccc18dddafa95= b97 > dashboard link: https://syzkaller.appspot.com/bug?extid=3Da6f4d69b9b23404= bbabf > compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b797= 6-1~exp1~20250708183702.136), Debian LLD 20.1.8 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=3D1573b214580= 000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=3D12b515cd98000= 0 >=20 > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/335d7c35cbbe/dis= k-d104e3d1.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/72dbd901415b/vmlinu= x-d104e3d1.xz > kernel image: https://storage.googleapis.com/syzbot-assets/3ff1353d0870/b= zImage-d104e3d1.xz >=20 > IMPORTANT: if you fix the issue, please add the following tag to the comm= it: > Reported-by: syzbot+a6f4d69b9b23404bbabf@syzkaller.appspotmail.com >=20 > ------------[ cut here ]------------ > WARNING: CPU: 1 PID: 6128 at kernel/locking/lockdep.c:6606 lockdep_unregi= ster_key+0x2ca/0x310 kernel/locking/lockdep.c:6606 > Modules linked in: > CPU: 1 UID: 0 PID: 6128 Comm: syz.4.21 Not tainted syzkaller #0 PREEMPT_{= RT,(full)}=20 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS G= oogle 08/18/2025 > RIP: 0010:lockdep_unregister_key+0x2ca/0x310 kernel/locking/lockdep.c:660= 6 > Code: 50 e4 0f 48 3b 44 24 10 0f 84 26 fe ff ff e8 bd cd 17 09 e8 e8 ce 1= 7 09 41 f7 c7 00 02 00 00 74 bd fb 40 84 ed 75 bc eb cd 90 <0f> 0b 90 e9 19= ff ff ff 90 0f 0b 90 e9 2a ff ff ff 48 c7 c7 d0 ac > RSP: 0018:ffffc90003e870d0 EFLAGS: 00010002 > RAX: eb1525397f5bdf00 RBX: ffff88803c121148 RCX: 1ffff920007d0dfc > RDX: 0000000000000000 RSI: ffffffff8acb1500 RDI: ffffffff8b1dd0e0 > RBP: 00000000ffffffea R08: ffffffff8eb5aa37 R09: 1ffffffff1d6b546 > R10: dffffc0000000000 R11: fffffbfff1d6b547 R12: 0000000000000000 > R13: ffff88814d1b8900 R14: 0000000000000000 R15: 0000000000000203 > FS: 00007f773f75e6c0(0000) GS:ffff88812712f000(0000) knlGS:0000000000000= 000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007ffdaea3af52 CR3: 000000003a5ca000 CR4: 00000000003526f0 > Call Trace: > > __kmem_cache_release+0xe3/0x1e0 mm/slub.c:7696 > do_kmem_cache_create+0x74e/0x790 mm/slub.c:8575 > create_cache mm/slab_common.c:242 [inline] > __kmem_cache_create_args+0x1ce/0x330 mm/slab_common.c:340 > nfsd_file_cache_init+0x1d6/0x530 fs/nfsd/filecache.c:816 > nfsd_startup_generic fs/nfsd/nfssvc.c:282 [inline] > nfsd_startup_net fs/nfsd/nfssvc.c:377 [inline] > nfsd_svc+0x393/0x900 fs/nfsd/nfssvc.c:786 > nfsd_nl_threads_set_doit+0x84a/0x960 fs/nfsd/nfsctl.c:1639 > genl_family_rcv_msg_doit+0x212/0x300 net/netlink/genetlink.c:1115 > genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] > genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 > netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 > genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 > netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] > netlink_unicast+0x846/0xa10 net/netlink/af_netlink.c:1346 > netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 > sock_sendmsg_nosec net/socket.c:727 [inline] > __sock_sendmsg+0x219/0x270 net/socket.c:742 > ____sys_sendmsg+0x508/0x820 net/socket.c:2630 > ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 > __sys_sendmsg net/socket.c:2716 [inline] > __do_sys_sendmsg net/socket.c:2721 [inline] > __se_sys_sendmsg net/socket.c:2719 [inline] > __x64_sys_sendmsg+0x1a1/0x260 net/socket.c:2719 > do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] > do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7f77400eeec9 > Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f= 7 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 a8 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007f773f75e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > RAX: ffffffffffffffda RBX: 00007f7740345fa0 RCX: 00007f77400eeec9 > RDX: 0000000000008004 RSI: 0000200000000180 RDI: 0000000000000006 > RBP: 00007f7740171f91 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 00007f7740346038 R14: 00007f7740345fa0 R15: 00007ffce616f8d8 > >=20 >=20 > --- > 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. >=20 > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. >=20 > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title >=20 > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. >=20 > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) >=20 > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report >=20 > If you want to undo deduplication, reply with: > #syz undup This happened in the context of userland calling the (privileged) netlink operation to start the threads in the server. As part of that, the server allocates a slabcache for struct nfsd_file_mark: nfsd_file_mark_slab =3D KMEM_CACHE(nfsd_file_mark, 0); if (!nfsd_file_mark_slab) { pr_err("nfsd: unable to create nfsd_file_mark_slab\n"); goto out_err; } Allocating that slabcache failed, so do_kmem_cache_create() called __kmem_cache_release() on the way out. That triggered the lockdep warning which is this in lockdep_unregister_key(): WARN_ON_ONCE(!found && debug_locks); So it tried to tear down a lockdep key, but it didn't exist? This doesn't seem to be nfsd related either. I'll hand off to mm. #syz set subsystems: mm --=20 Jeff Layton