[2.6.20.21 review 25/35] nfs: fix oops re sysctls and V4 support

From: Willy Tarreau
Date: Sat Oct 13 2007 - 10:57:44 EST


commit 49af7ee181f4f516ac99eba85d3f70ed42cabe76 in mainline.

NFS unregisters sysctls only if V4 support is compiled in. However, sysctl
table is not V4 specific, so unregister it always.

Steps to reproduce:

[build nfs.ko with CONFIG_NFS_V4=n]
modrobe nfs
rmmod nfs
ls /proc/sys

Unable to handle kernel paging request at ffffffff880661c0 RIP:
[<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
PGD 203067 PUD 207063 PMD 7e216067 PTE 0
Oops: 0000 [1] SMP
CPU 1
Modules linked in: lockd nfs_acl sunrpc
Pid: 3335, comm: ls Not tainted 2.6.23-rc3-bloat #2
RIP: 0010:[<ffffffff802af8e3>] [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
RSP: 0018:ffff81007fd93e78 EFLAGS: 00010286
RAX: ffffffff880661c0 RBX: ffffffff80466370 RCX: ffffffff880661c0
RDX: 00000000000014c0 RSI: ffff81007f3ad020 RDI: ffff81007efd8b40
RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff802a8570 R12: ffffffff880661c0
R13: ffff81007e219640 R14: ffff81007efd8b40 R15: ffff81007ded7280
FS: 00002ba25ef03060(0000) GS:ffff81007ff81258(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffff880661c0 CR3: 000000007dfaf000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ls (pid: 3335, threadinfo ffff81007fd92000, task ffff81007d8a0000)
Stack: ffff81007f3ad150 ffffffff80283f30 ffff81007fd93f48 ffff81007efd8b40
ffff81007ee00440 0000000422222222 0000000200035593 ffffffff88037e9a
2222222222222222 ffffffff80466500 ffff81007e416400 ffff81007e219640
Call Trace:
[<ffffffff80283f30>] filldir+0x0/0xf0
[<ffffffff80283f30>] filldir+0x0/0xf0
[<ffffffff802840c7>] vfs_readdir+0xa7/0xc0
[<ffffffff80284376>] sys_getdents+0x96/0xe0
[<ffffffff8020bb3e>] system_call+0x7e/0x83

Code: 41 8b 14 24 85 d2 74 dc 49 8b 44 24 08 48 85 c0 74 e7 49 3b
RIP [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
RSP <ffff81007fd93e78>
CR2: ffffffff880661c0
Kernel panic - not syncing: Fatal exception

Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Acked-by: Trond Myklebust <trond.myklebust@xxxxxxxxxx>
Cc: "J. Bruce Fields" <bfields@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
fs/nfs/super.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

Index: 2.6/fs/nfs/super.c
===================================================================
--- 2.6.orig/fs/nfs/super.c
+++ 2.6/fs/nfs/super.c
@@ -180,8 +180,8 @@ void __exit unregister_nfs_fs(void)
remove_shrinker(acl_shrinker);
#ifdef CONFIG_NFS_V4
unregister_filesystem(&nfs4_fs_type);
- nfs_unregister_sysctl();
#endif
+ nfs_unregister_sysctl();
unregister_filesystem(&nfs_fs_type);
}


--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/