On Tue, 11 Jul 2006 16:26:48 +1200 Bill Ryder wrote:
> Hello all,
>
> I've read all the stuff on submitting patches and this seems to be the
> place.
>
> Please CC me on any replies to this (although I do watch this through
> list with gmane)
>
> Here's the patch description. I've attached the patch. Hopefully I've
> followed the rules in Documentation/Submit* - apart from CC'ing Linus).
6) No MIME, no links, no compression, no attachments. Just plain text.
Attachments make it difficult to review/comment.
You'll likely need to coax Andrew into merging/testing it in -mm
rather than sending it to Linus.
> Summary:
>
> Patch to allow the option of not sorting a process's supplemental
> (also known ask secondary aka supplementary) group list.
>
> Setting the kernel config option of UNSORTED_SUPPLEMENTAL_GROUPLIST
> will allow the use of setgroups(2) to reorder a supplemental
> group list to work around the NFS AUTH_UNIX 16 group limit.
>
> In fact I think this should be the default option because anyone using
> setgroups
> may get an unpleasant surprise with 2.6.x. But for now this patch makes
> it an option.
>
> Longer version:
>
> Like many places Weta Digital (we did the VFX for Lord of the Rings,
> King Kong etc)
> uses supplemental group lists to allow users access to multiple
> directories and files (films mostly in our
> case) . Unfortunately NFSv2 and NFSv3 AUTH_UNIX flavour authentication
> is hardcoded to only support 16 supplemental groups. Since we currently
> have some users and processes which need to be in more than 16 groups
> we use setgroups to build a list of groups that a process requires when
> they access data on nfs exported filesystems.
>
> This worked fine for the 2.4.x kernels. 2.6.x is designed to handle
> thousands of groups for a single user. To support that the kernel was
> changed to sort the group list, then use a binary search to decide if
> a user was in the correct group. Unfortunately this BREAKS the use of
> setgroups(2) to put the 16 most important groups first.
>
> This patch provides the option of not sorting that list. The help
> describes the pitfalls of not sorting the groups (performance when
> there are a lot of groups).
Patch comments:
Keep Kconfig help text to less than 80 columns so that it fits in
an xterm without requiring left/right scrolling.
Keep source code/comments within 80 columns (for xterms again).
So this comment needs to be broken/split:
+/* if USE_UNSORTED_SUPPLEMENTAL_GROUPS is set this is a linear search. If not it's a binary search */
In the groups_search() function, all data needs to be declared
before any executable code statements.
Lines like this:
+#ifdef USE_UNSORTED_SUPPLEMENTAL_GROUPS
should be:
+#ifdef CONFIG_USE_UNSORTED_SUPPLEMENTAL_GROUPS
i.e., the config system prefixes all config symbols with CONFIG_.
Was it tested like this?
Look at Documentation/SubmitChecklist along with
Documentation/SubmittingPatches.
---
~Randy
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
