From 68d75ed4b84a0806ecd4bc14da4759713b23a532 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 18 May 2010 12:58:33 -0700 Subject: [PATCH] sysfs: Remove usage of S_BIAS to avoid merge conflict with the vfs tree In Al's latest vfs tree the code is reworked and S_BIAS has been removed. It turns out that checking to see if a super block is in the middle of an unmount in sysfs_exit_ns is unnecessary because we remove the super_block from the s_supers/s_instances list before struct sysfs_super_info pointed to by sb->s_fs_info is freed. For now just delete the unnecessary check to see if a superblock is in the middle of an unmount, it isn't necessary with or without Al's changes and it just causes a needless conflict. Reported-by: Stephen Rothwell Cc: Al Viro Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/mount.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 1afa32ba242c..281c0c9bc39f 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -138,6 +138,9 @@ static void sysfs_kill_sb(struct super_block *sb) { struct sysfs_super_info *info = sysfs_info(sb); + /* Remove the superblock from fs_supers/s_instances + * so we can't find it, before freeing sysfs_super_info. + */ kill_anon_super(sb); kfree(info); } @@ -156,9 +159,11 @@ void sysfs_exit_ns(enum kobj_ns_type type, const void *ns) spin_lock(&sb_lock); list_for_each_entry(sb, &sysfs_fs_type.fs_supers, s_instances) { struct sysfs_super_info *info = sysfs_info(sb); - /* Ignore superblocks that are in the process of unmounting */ - if (sb->s_count <= S_BIAS) - continue; + /* + * If we see a superblock on the fs_supers/s_instances + * list the unmount has not completed and sb->s_fs_info + * points to a valid struct sysfs_super_info. + */ /* Ignore superblocks with the wrong ns */ if (info->ns[type] != ns) continue;