[syzbot] WARNING in d_make_discardable

[syzbot <syzbot+2e3c70a51d4ac0f6bdd9@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    5b0764a53235 Merge tag 'drm-next-2026-10-21' of https://gi..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=15f3470d580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6e9d69cbadaeb907
dashboard link: https://syzkaller.appspot.com/bug?extid=2e3c70a51d4ac0f6bdd9
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14089aa5580000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2e3c70a51d4ac0f6bdd9@syzkaller.appspotmail.com

------------[ cut here ]------------
!(dentry->d_flags & DCACHE_PERSISTENT)
WARNING: fs/dcache.c:1063 at d_make_discardable+0x28e/0x2f0 fs/dcache.c:1063, CPU#3: syz-executor121/6123
Modules linked in:
CPU: 3 UID: 0 PID: 6123 Comm: syz-executor121 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:d_make_discardable+0x28e/0x2f0 fs/dcache.c:1063
Code: 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 5b 83 0b 40 e9 2e ff ff ff e8 93 c5 69 ff 90 <0f> 0b 90 e9 c8 fd ff ff e8 05 d8 e2 ff e9 14 fe ff ff 48 89 df e8
RSP: 0018:ffffc900036b7280 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88803d9b2680 RCX: 0000000000000001
RDX: ffff8880270e0000 RSI: ffffffff82a4457d RDI: ffff8880270e0000
RBP: 0000000000100080 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88803fc2e4e0 R15: ffff888046af5e80
FS:  00007ff6448646c0(0000) GS:ffff8880d47ba000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056251a682e28 CR3: 0000000038934000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __simple_recursive_removal+0x276/0x5c0 fs/libfs.c:625
 rpc_remove_client_dir+0xf0/0x140 net/sunrpc/rpc_pipe.c:898
 __rpc_clnt_remove_pipedir net/sunrpc/clnt.c:100 [inline]
 __rpc_clnt_remove_pipedir net/sunrpc/clnt.c:97 [inline]
 rpc_client_register+0x605/0x6f0 net/sunrpc/clnt.c:333
 rpc_new_client+0x977/0x1300 net/sunrpc/clnt.c:437
 rpc_create_xprt+0xd9/0x440 net/sunrpc/clnt.c:483
 rpc_create+0x46e/0x7f0 net/sunrpc/clnt.c:619
 nfs_create_rpc_client+0x6a1/0x8f0 fs/nfs/client.c:575
 nfs4_alloc_client+0x8f0/0xd70 fs/nfs/nfs4client.c:233
 nfs_get_client+0x87b/0x1230 fs/nfs/client.c:468
 nfs4_set_client+0x3f6/0x640 fs/nfs/nfs4client.c:757
 nfs4_init_server.isra.0+0x5ad/0xf60 fs/nfs/nfs4client.c:1002
 nfs4_create_server+0x185/0x2b0 fs/nfs/nfs4client.c:1051
 nfs4_try_get_tree+0x93/0x140 fs/nfs/nfs4super.c:228
 nfs_get_tree+0xa61/0x1450 fs/nfs/fs_context.c:1620
 vfs_get_tree+0x92/0x320 fs/super.c:1943
 fc_mount fs/namespace.c:1282 [inline]
 do_new_mount_fc fs/namespace.c:3910 [inline]
 do_new_mount fs/namespace.c:3986 [inline]
 path_mount+0x7d0/0x2850 fs/namespace.c:4337
 do_mount fs/namespace.c:4350 [inline]
 __do_sys_mount fs/namespace.c:4565 [inline]
 __se_sys_mount fs/namespace.c:4542 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4542
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff64609d69a
Code: 48 c7 c2 d0 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 d0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff6448640d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffc99ea1760 RCX: 00007ff64609d69a
RDX: 00007ff646109053 RSI: 00007ff6448640e0 RDI: 00007ff644864120
RBP: 00007ff644864160 R08: 00007ff644864160 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff644864120
R13: 00007ff6448640e0 R14: 0000000000000003 R15: 0000000000000004
 </TASK>


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