forked from Minki/linux
7ef55b8a05
When I was performing some operations on NFS, I got below error on server side. ============================================= [ INFO: possible recursive locking detected ] 2.6.19-prep #1 --------------------------------------------- nfsd4/3525 is trying to acquire lock: (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24 but task is already holding lock: (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24 other info that might help us debug this: 2 locks held by nfsd4/3525: #0: (client_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24 #1: (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24 stack backtrace: [<c04051ed>] show_trace_log_lvl+0x58/0x16a [<c04057fa>] show_trace+0xd/0x10 [<c0405913>] dump_stack+0x19/0x1b [<c043b6f1>] __lock_acquire+0x778/0x99c [<c043be86>] lock_acquire+0x4b/0x6d [<c0611ceb>] __mutex_lock_slowpath+0xbc/0x20a [<c0611e5a>] mutex_lock+0x21/0x24 [<c047fd7e>] vfs_rmdir+0x76/0xf8 [<f94b7ce9>] nfsd4_clear_clid_dir+0x2c/0x41 [nfsd] [<f94b7de9>] nfsd4_remove_clid_dir+0xb1/0xe8 [nfsd] [<f94b307b>] laundromat_main+0x9b/0x1c3 [nfsd] [<c04333d6>] run_workqueue+0x7a/0xbb [<c0433d0b>] worker_thread+0xd2/0x107 [<c0436285>] kthread+0xc3/0xf2 [<c0402005>] kernel_thread_helper+0x5/0xb =================================================================== Cause for this problem was,2 successive mutex_lock calls on 2 diffrent inodes ,as shown below static int nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry) { int status; /* For now this directory should already be empty, but we empty it of * any regular files anyway, just in case the directory was created by * a kernel from the future.... */ nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file); mutex_lock(&dir->d_inode->i_mutex); status = vfs_rmdir(dir->d_inode, dentry); ... int vfs_rmdir(struct inode *dir, struct dentry *dentry) { int error = may_delete(dir, dentry, 1); if (error) return error; if (!dir->i_op || !dir->i_op->rmdir) return -EPERM; DQUOT_INIT(dir); mutex_lock(&dentry->d_inode->i_mutex); ... So I have developed the patch to overcome this problem. Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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.. | ||
auth.c | ||
export.c | ||
lockd.c | ||
Makefile | ||
nfs2acl.c | ||
nfs3acl.c | ||
nfs3proc.c | ||
nfs3xdr.c | ||
nfs4acl.c | ||
nfs4callback.c | ||
nfs4idmap.c | ||
nfs4proc.c | ||
nfs4recover.c | ||
nfs4state.c | ||
nfs4xdr.c | ||
nfscache.c | ||
nfsctl.c | ||
nfsfh.c | ||
nfsproc.c | ||
nfssvc.c | ||
nfsxdr.c | ||
stats.c | ||
vfs.c |