| Message ID | m11utvytg4.fsf@fess.ebiederm.org |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On 10/30/2011 05:49 AM, Eric W. Biederman wrote: > Jiri Slaby <jslaby@suse.cz> writes: > >> On 10/25/2011 03:13 PM, Greg KH wrote: >>> On Tue, Oct 25, 2011 at 01:46:11PM +0200, Linus Torvalds wrote: >>>> Anyway, after that rant about really bad practices, let me say that I >>>> did fix up the conflict and I think it's right. But I won't guarantee >>>> it, so please check the changes to fs/sysfs/dir.c. >>> >>> I think it looks ok, I've booted the merge result, and am typing and >>> sending this from the new kernel, and it hasn't crashed yet :) >> >> Hi, maybe this was not caused by the merge, but the patch[1] causes this >> mess in /sys/class/net/ for me: >> l????????? ? ? ? ? ? eth1 >> >> This happens after one renames a net device -- the new name is eth1 here. >> >> [1] 4f72c0cab40 (sysfs: use rb-tree for name lookups) > > This looks pretty fixable but today sysfs_rename does not do anything > with the to move a renamed entry to a different position in the rbtree. > > If the directory itself changes sysfs_rename should be fine, and it > looks like a trivial patch to always apply the directory rename logic > in sysfs_rename. > > I think all we need is something like the untested patch below to fix > the network device rename problem. Looks like it works. Thanks. > diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c > index 48ffbdf..a294068 100644 > --- a/fs/sysfs/dir.c > +++ b/fs/sysfs/dir.c > @@ -865,14 +865,13 @@ int sysfs_rename(struct sysfs_dirent *sd, > sd->s_name = new_name; > } > > - /* Remove from old parent's list and insert into new parent's list. */ > - if (sd->s_parent != new_parent_sd) { > - sysfs_unlink_sibling(sd); > - sysfs_get(new_parent_sd); > - sysfs_put(sd->s_parent); > - sd->s_parent = new_parent_sd; > - sysfs_link_sibling(sd); > - } > + /* Move to the appropriate place in the appropriate directories rbtree. */ > + sysfs_unlink_sibling(sd); > + sysfs_get(new_parent_sd); > + sysfs_put(sd->s_parent); > + sd->s_parent = new_parent_sd; > + sysfs_link_sibling(sd); > + > sd->s_ns = new_ns; > > error = 0; >
On Tue, Nov 01, 2011 at 07:06:17AM -0700, Eric W. Biederman wrote: > > In sysfs_rename remove the optimization of not calling sysfs_unlink_sibling > and sysfs_link_sibling if the renamed parent directory is not changing. > This optimization is no longer valid now that sysfs dirents are stored in an > rbtree sorted by name. > > Move the assignment of s_ns before the call of sysfs_link_sibling. With no > sysfs_dirent fields changing after the call of sysfs_link_sibling this allows > sysfs_link_sibling to take any of the directory entries into account when > it builds the rbtrees, and s_ns looks like a prime canidate to be used > in the rbtree in the future. > > Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Looks good, Linus, thanks for taking this in your tree already. greg k-h -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 48ffbdf..a294068 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -865,14 +865,13 @@ int sysfs_rename(struct sysfs_dirent *sd, sd->s_name = new_name; } - /* Remove from old parent's list and insert into new parent's list. */ - if (sd->s_parent != new_parent_sd) { - sysfs_unlink_sibling(sd); - sysfs_get(new_parent_sd); - sysfs_put(sd->s_parent); - sd->s_parent = new_parent_sd; - sysfs_link_sibling(sd); - } + /* Move to the appropriate place in the appropriate directories rbtree. */ + sysfs_unlink_sibling(sd); + sysfs_get(new_parent_sd); + sysfs_put(sd->s_parent); + sd->s_parent = new_parent_sd; + sysfs_link_sibling(sd); + sd->s_ns = new_ns; error = 0;