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2018-06-12Merge tag 'overflow-v4.18-rc1-part2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull more overflow updates from Kees Cook: "The rest of the overflow changes for v4.18-rc1. This includes the explicit overflow fixes from Silvio, further struct_size() conversions from Matthew, and a bug fix from Dan. But the bulk of it is the treewide conversions to use either the 2-factor argument allocators (e.g. kmalloc(a * b, ...) into kmalloc_array(a, b, ...) or the array_size() macros (e.g. vmalloc(a * b) into vmalloc(array_size(a, b)). Coccinelle was fighting me on several fronts, so I've done a bunch of manual whitespace updates in the patches as well. Summary: - Error path bug fix for overflow tests (Dan) - Additional struct_size() conversions (Matthew, Kees) - Explicitly reported overflow fixes (Silvio, Kees) - Add missing kvcalloc() function (Kees) - Treewide conversions of allocators to use either 2-factor argument variant when available, or array_size() and array3_size() as needed (Kees)" * tag 'overflow-v4.18-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (26 commits) treewide: Use array_size in f2fs_kvzalloc() treewide: Use array_size() in f2fs_kzalloc() treewide: Use array_size() in f2fs_kmalloc() treewide: Use array_size() in sock_kmalloc() treewide: Use array_size() in kvzalloc_node() treewide: Use array_size() in vzalloc_node() treewide: Use array_size() in vzalloc() treewide: Use array_size() in vmalloc() treewide: devm_kzalloc() -> devm_kcalloc() treewide: devm_kmalloc() -> devm_kmalloc_array() treewide: kvzalloc() -> kvcalloc() treewide: kvmalloc() -> kvmalloc_array() treewide: kzalloc_node() -> kcalloc_node() treewide: kzalloc() -> kcalloc() treewide: kmalloc() -> kmalloc_array() mm: Introduce kvcalloc() video: uvesafb: Fix integer overflow in allocation UBIFS: Fix potential integer overflow in allocation leds: Use struct_size() in allocation Convert intel uncore to struct_size ...
2018-06-12treewide: Use array_size() in vzalloc()Kees Cook
The vzalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vzalloc(a * b) with: vzalloc(array_size(a, b)) as well as handling cases of: vzalloc(a * b * c) with: vzalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vzalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(char) * COUNT + COUNT , ...) | vzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vzalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vzalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vzalloc(C1 * C2 * C3, ...) | vzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vzalloc(C1 * C2, ...) | vzalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-11nfsd: Do not refuse to serve out of cacheTrond Myklebust
Currently the knfsd replay cache appears to try to refuse replying to retries that come within 200ms of the cache entry being created. That makes limited sense in today's world of high speed TCP. After a TCP disconnection, a client can very easily reconnect and retry an rpc in less than 200ms. If this logic drops that retry, however, the client may be quite slow to retry again. This logic is original to the first reply cache implementation in 2.1, and may have made more sense for UDP clients that retried much more frequently. After this patch we will still drop on finding the original request still in progress. We may want to fix that as well at some point, though it's less likely. Note that svc_check_conn_limits is often the cause of those disconnections. We may want to fix that some day. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-27lib/vsprintf.c: remove %Z supportAlexey Dobriyan
Now that %z is standartised in C99 there is no reason to support %Z. Unlike %L it doesn't even make format strings smaller. Use BUILD_BUG_ON in a couple ATM drivers. In case anyone didn't notice lib/vsprintf.o is about half of SLUB which is in my opinion is quite an achievement. Hopefully this patch inspires someone else to trim vsprintf.c more. Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-01nfsd: more robust allocation failure handling in nfsd_reply_cache_initJeff Layton
Currently, we try to allocate the cache as a single, large chunk, which can fail if no big chunks of memory are available. We _do_ try to size it according to the amount of memory in the box, but if the server is started well after boot time, then the allocation can fail due to memory fragmentation. Fall back to doing a vzalloc if the kcalloc fails, and switch the shutdown code to do a kvfree to handle freeing correctly. Reported-by: Olaf Hering <olaf@aepfle.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-11-10nfsd: remove recurring workqueue job to clean DRCJeff Layton
We have a shrinker, we clean out the cache when nfsd is shut down, and prune the chains on each request. A recurring workqueue job seems like unnecessary overhead. Just remove it. Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-10-12nfsd: drop null test before destroy functionsJulia Lawall
Remove unneeded NULL test. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x; @@ -if (x != NULL) { \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x); x = NULL; -} // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-03-20NFSD: Error out when register_shrinker() failKinglong Mee
If register_shrinker() failed, nfsd will cause a NULL pointer access as, [ 9250.875465] nfsd: last server has exited, flushing export cache [ 9251.427270] BUG: unable to handle kernel NULL pointer dereference at (null) [ 9251.427393] IP: [<ffffffff8136fc29>] __list_del_entry+0x29/0xd0 [ 9251.427579] PGD 13e4d067 PUD 13e4c067 PMD 0 [ 9251.427633] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC [ 9251.427706] Modules linked in: ip6t_rpfilter ip6t_REJECT bnep bluetooth xt_conntrack cfg80211 rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw btrfs xfs microcode ppdev serio_raw pcspkr xor libcrc32c raid6_pq e1000 parport_pc parport i2c_piix4 i2c_core nfsd(OE-) auth_rpcgss nfs_acl lockd sunrpc(E) ata_generic pata_acpi [ 9251.428240] CPU: 0 PID: 1557 Comm: rmmod Tainted: G OE 3.16.0-rc2+ #22 [ 9251.428366] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013 [ 9251.428496] task: ffff880000849540 ti: ffff8800136f4000 task.ti: ffff8800136f4000 [ 9251.428593] RIP: 0010:[<ffffffff8136fc29>] [<ffffffff8136fc29>] __list_del_entry+0x29/0xd0 [ 9251.428696] RSP: 0018:ffff8800136f7ea0 EFLAGS: 00010207 [ 9251.428751] RAX: 0000000000000000 RBX: ffffffffa0116d48 RCX: dead000000200200 [ 9251.428814] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa0116d48 [ 9251.428876] RBP: ffff8800136f7ea0 R08: ffff8800136f4000 R09: 0000000000000001 [ 9251.428939] R10: 8080808080808080 R11: 0000000000000000 R12: ffffffffa011a5a0 [ 9251.429002] R13: 0000000000000800 R14: 0000000000000000 R15: 00000000018ac090 [ 9251.429064] FS: 00007fb9acef0740(0000) GS:ffff88003fa00000(0000) knlGS:0000000000000000 [ 9251.429164] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9251.429221] CR2: 0000000000000000 CR3: 0000000031a17000 CR4: 00000000001407f0 [ 9251.429306] Stack: [ 9251.429410] ffff8800136f7eb8 ffffffff8136fcdd ffffffffa0116d20 ffff8800136f7ed0 [ 9251.429511] ffffffff8118a0f2 0000000000000000 ffff8800136f7ee0 ffffffffa00eb765 [ 9251.429610] ffff8800136f7ef0 ffffffffa010e93c ffff8800136f7f78 ffffffff81104ac2 [ 9251.429709] Call Trace: [ 9251.429755] [<ffffffff8136fcdd>] list_del+0xd/0x30 [ 9251.429896] [<ffffffff8118a0f2>] unregister_shrinker+0x22/0x40 [ 9251.430037] [<ffffffffa00eb765>] nfsd_reply_cache_shutdown+0x15/0x90 [nfsd] [ 9251.430106] [<ffffffffa010e93c>] exit_nfsd+0x9/0x6cd [nfsd] [ 9251.430192] [<ffffffff81104ac2>] SyS_delete_module+0x162/0x200 [ 9251.430280] [<ffffffff81013b69>] ? do_notify_resume+0x59/0x90 [ 9251.430395] [<ffffffff816f2369>] system_call_fastpath+0x16/0x1b [ 9251.430457] Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de 48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 ad de 48 39 c8 74 7a <4c> 8b 00 4c 39 c7 75 53 4c 8b 42 08 4c 39 c7 75 2b 48 89 42 08 [ 9251.430691] RIP [<ffffffff8136fc29>] __list_del_entry+0x29/0xd0 [ 9251.430755] RSP <ffff8800136f7ea0> [ 9251.430805] CR2: 0000000000000000 [ 9251.431033] ---[ end trace 080f3050d082b4ea ]--- Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09sunrpc: add a generic rq_flags field to svc_rqst and move rq_secure to itJeff Layton
In a later patch, we're going to need some atomic bit flags. Since that field will need to be an unsigned long, we mitigate that space consumption by migrating some other bitflags to the new field. Start with the rq_secure flag. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17nfsd: Reorder nfsd_cache_match to check more powerful discriminators firstTrond Myklebust
We would normally expect the xid and the checksum to be the best discriminators. Check them before looking at the procedure number, etc. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17nfsd: split DRC global spinlock into per-bucket locksTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17nfsd: convert num_drc_entries to an atomic_tTrond Myklebust
...so we can remove the spinlocking around it. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17nfsd: Remove the cache_hash listTrond Myklebust
Now that the lru list is per-bucket, we don't need a second list for searches. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17nfsd: convert the lru list into a per-bucket thingTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17nfsd: Clean up drc cache in preparation for global spinlock eliminationTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-06-23nfsd: clean up sparse endianness warnings in nfscache.cJeff Layton
We currently hash the XID to determine a hash bucket to use for the reply cache entry, which is fed into hash_32 without byte-swapping it. Add __force to make sparse happy, and add some comments to explain why. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-06-06nfsd: don't halt scanning the DRC LRU list when there's an RC_INPROG entryJeff Layton
Currently, the DRC cache pruner will stop scanning the list when it hits an entry that is RC_INPROG. It's possible however for a call to take a *very* long time. In that case, we don't want it to block other entries from being pruned if they are expired or we need to trim the cache to get back under the limit. Fix the DRC cache pruner to just ignore RC_INPROG entries. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-12-11nfsd: don't try to reuse an expired DRC entry off the listJeff Layton
Currently when we are processing a request, we try to scrape an expired or over-limit entry off the list in preference to allocating a new one from the slab. This is unnecessarily complicated. Just use the slab layer. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-12-10nfsd: when reusing an existing repcache entry, unhash it firstJeff Layton
The DRC code will attempt to reuse an existing, expired cache entry in preference to allocating a new one. It'll then search the cache, and if it gets a hit it'll then free the cache entry that it was going to reuse. The cache code doesn't unhash the entry that it's going to reuse however, so it's possible for it end up designating an entry for reuse and then subsequently freeing the same entry after it finds it. This leads it to a later use-after-free situation and usually some list corruption warnings or an oops. Fix this by simply unhashing the entry that we intend to reuse. That will mean that it's not findable via a search and should prevent this situation from occurring. Cc: stable@vger.kernel.org # v3.10+ Reported-by: Christoph Hellwig <hch@infradead.org> Reported-by: g. artim <gartim@gmail.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-09-10fs: convert fs shrinkers to new scan/count APIDave Chinner
Convert the filesystem shrinkers to use the new API, and standardise some of the behaviours of the shrinkers at the same time. For example, nr_to_scan means the number of objects to scan, not the number of objects to free. I refactored the CIFS idmap shrinker a little - it really needs to be broken up into a shrinker per tree and keep an item count with the tree root so that we don't need to walk the tree every time the shrinker needs to count the number of objects in the tree (i.e. all the time under memory pressure). [glommer@openvz.org: fixes for ext4, ubifs, nfs, cifs and glock. Fixes are needed mainly due to new code merged in the tree] [assorted fixes folded in] Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Glauber Costa <glommer@openvz.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: Arve Hjønnevåg <arve@android.com> Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Rientjes <rientjes@google.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: J. Bruce Fields <bfields@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Kent Overstreet <koverstreet@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-30nfsd: make symbol nfsd_reply_cache_shrinker staticWei Yongjun
symbol 'nfsd_reply_cache_shrinker' only used within this file. It should be static. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-04-03nfsd: scale up the number of DRC hash buckets with cache sizeJeff Layton
We've now increased the size of the duplicate reply cache by quite a bit, but the number of hash buckets has not changed. So, we've gone from an average hash chain length of 16 in the old code to 4096 when the cache is its largest. Change the code to scale out the number of buckets with the max size of the cache. At the same time, we also need to fix the hash function since the existing one isn't really suitable when there are more than 256 buckets. Move instead to use the stock hash_32 function for this. Testing on a machine that had 2048 buckets showed that this gave a smaller longest:average ratio than the existing hash function: The formula here is longest hash bucket searched divided by average number of entries per bucket at the time that we saw that longest bucket: old hash: 68/(39258/2048) == 3.547404 hash_32: 45/(33773/2048) == 2.728807 Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-04-03nfsd: keep stats on worst hash balancing seen so farJeff Layton
The typical case with the DRC is a cache miss, so if we keep track of the max number of entries that we've ever walked over in a search, then we should have a reasonable estimate of the longest hash chain that we've ever seen. With that, we'll also keep track of the total size of the cache when we see the longest chain. In the case of a tie, we prefer to track the smallest total cache size in order to properly gauge the worst-case ratio of max vs. avg chain length. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-04-03nfsd: add new reply_cache_stats file in nfsdfsJeff Layton
For presenting statistics relating to duplicate reply cache. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-04-03nfsd: track memory utilization by the DRCJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-04-03nfsd: break out comparator into separate functionJeff Layton
Break out the function that compares the rqstp and checksum against a reply cache entry. While we're at it, track the efficacy of the checksum over the NFS data by tracking the cases where we would have incorrectly matched a DRC entry if we had not tracked it or the length. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-04-03nfsd: eliminate one of the DRC cache searchesJeff Layton
The most common case is to do a search of the cache, followed by an insert. In the case where we have to allocate an entry off the slab, then we end up having to redo the search, which is wasteful. Better optimize the code for the common case by eliminating the initial search of the cache and always preallocating an entry. In the case of a cache hit, we'll end up just freeing that entry but that's preferable to an extra search. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-03-18nfsd: fix startup order in nfsd_reply_cache_initJeff Layton
If we end up doing "goto out_nomem" in this function, we'll call nfsd_reply_cache_shutdown. That will attempt to walk the LRU list and free entries, but that list may not be initialized yet if the server is starting up for the first time. It's also possible for the shrinker to kick in before we've initialized the LRU list. Rearrange the initialization so that the LRU list_head and cache size are initialized before doing any of the allocations that might fail. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-03-18nfsd: only unhash DRC entries that are in the hashtableJeff Layton
It's not safe to call hlist_del() on a newly initialized hlist_node. That leads to a NULL pointer dereference. Only do that if the entry is hashed. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-28Merge branch 'for-3.9' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd changes from J Bruce Fields: "Miscellaneous bugfixes, plus: - An overhaul of the DRC cache by Jeff Layton. The main effect is just to make it larger. This decreases the chances of intermittent errors especially in the UDP case. But we'll need to watch for any reports of performance regressions. - Containerized nfsd: with some limitations, we now support per-container nfs-service, thanks to extensive work from Stanislav Kinsbursky over the last year." Some notes about conflicts, since there were *two* non-data semantic conflicts here: - idr_remove_all() had been added by a memory leak fix, but has since become deprecated since idr_destroy() does it for us now. - xs_local_connect() had been added by this branch to make AF_LOCAL connections be synchronous, but in the meantime Trond had changed the calling convention in order to avoid a RCU dereference. There were a couple of more obvious actual source-level conflicts due to the hlist traversal changes and one just due to code changes next to each other, but those were trivial. * 'for-3.9' of git://linux-nfs.org/~bfields/linux: (49 commits) SUNRPC: make AF_LOCAL connect synchronous nfsd: fix compiler warning about ambiguous types in nfsd_cache_csum svcrpc: fix rpc server shutdown races svcrpc: make svc_age_temp_xprts enqueue under sv_lock lockd: nlmclnt_reclaim(): avoid stack overflow nfsd: enable NFSv4 state in containers nfsd: disable usermode helper client tracker in container nfsd: use proper net while reading "exports" file nfsd: containerize NFSd filesystem nfsd: fix comments on nfsd_cache_lookup SUNRPC: move cache_detail->cache_request callback call to cache_read() SUNRPC: remove "cache_request" argument in sunrpc_cache_pipe_upcall() function SUNRPC: rework cache upcall logic SUNRPC: introduce cache_detail->cache_request callback NFS: simplify and clean cache library NFS: use SUNRPC cache creation and destruction helper for DNS cache nfsd4: free_stid can be static nfsd: keep a checksum of the first 256 bytes of request sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer sunrpc: fix comment in struct xdr_buf definition ...
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-17nfsd: fix compiler warning about ambiguous types in nfsd_cache_csumJeff Layton
kbuild test robot says: tree: git://linux-nfs.org/~bfields/linux.git for-3.9 head: deb4534f4f3be7aea7d9d24c3b0d58f370cbf9ef commit: 01a7decf75930925322c5efc87af0b5e58eb8650 [32/44] nfsd: keep a checksum of the first 256 bytes of request config: i386-randconfig-x088 (attached as .config) All warnings: fs/nfsd/nfscache.c: In function 'nfsd_cache_csum': >> fs/nfsd/nfscache.c:266:9: warning: comparison of distinct pointer types lacks a cast [enabled by default] vim +266 fs/nfsd/nfscache.c 250 __wsum csum; 251 struct xdr_buf *buf = &rqstp->rq_arg; 252 const unsigned char *p = buf->head[0].iov_base; 253 size_t csum_len = min_t(size_t, buf->head[0].iov_len + buf->page_len, 254 RC_CSUMLEN); 255 size_t len = min(buf->head[0].iov_len, csum_len); 256 257 /* rq_arg.head first */ 258 csum = csum_partial(p, len, 0); 259 csum_len -= len; 260 261 /* Continue into page array */ 262 idx = buf->page_base / PAGE_SIZE; 263 base = buf->page_base & ~PAGE_MASK; 264 while (csum_len) { 265 p = page_address(buf->pages[idx]) + base; > 266 len = min(PAGE_SIZE - base, csum_len); 267 csum = csum_partial(p, len, csum); 268 csum_len -= len; 269 base = 0; 270 ++idx; 271 } 272 return csum; 273 } 274 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-15nfsd: fix comments on nfsd_cache_lookupJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-08nfsd: keep a checksum of the first 256 bytes of requestJeff Layton
Now that we're allowing more DRC entries, it becomes a lot easier to hit problems with XID collisions. In order to mitigate those, calculate a checksum of up to the first 256 bytes of each request coming in and store that in the cache entry, along with the total length of the request. This initially used crc32, but Chuck Lever and Jim Rees pointed out that crc32 is probably more heavyweight than we really need for generating these checksums, and recommended looking at using the same routines that are used to generate checksums for IP packets. On an x86_64 KVM guest measurements with ftrace showed ~800ns to use csum_partial vs ~1750ns for crc32. The difference probably isn't terribly significant, but for now we may as well use csum_partial. Signed-off-by: Jeff Layton <jlayton@redhat.com> Stones-thrown-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-05sunrpc: move address copy/cmp/convert routines and prototypes from clnt.h to ↵Jeff Layton
addr.h These routines are used by server and client code, so having them in a separate header would be best. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: register a shrinker for DRC cache entriesJeff Layton
Since we dynamically allocate them now, allow the system to call us up to release them if it gets low on memory. Since these entries aren't replaceable, only free ones that are expired or that are over the cap. The the seeks value is set to '1' however to indicate that freeing the these entries is low-cost. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: add recurring workqueue job to clean the cacheJeff Layton
It's not sufficient to only clean the cache when requests come in. What if we have a flurry of activity and then the server goes idle? Add a workqueue job that will clean the cache every RC_EXPIRE period. Care is taken to only run this when we expect to have entries expiring. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: when updating an entry with RC_NOCACHE, just free itJeff Layton
There's no need to keep entries around that we're declaring RC_NOCACHE. Ditto if there's a problem with the entry. With this change too, there's no need to test for RC_UNUSED in the search function. If the entry's in the hash table then it's either INPROG or DONE. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: remove the cache_disabled flagJeff Layton
With the change to dynamically allocate entries, the cache is never disabled on the fly. Remove this flag. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: dynamically allocate DRC entriesJeff Layton
The existing code keeps a fixed-size cache of 1024 entries. This is much too small for a busy server, and wastes memory on an idle one. This patch changes the code to dynamically allocate and free these cache entries. A cap on the number of entries is retained, but it's much larger than the existing value and now scales with the amount of low memory in the machine. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: track the number of DRC entries in the cacheJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: always move DRC entries to the end of LRU list when updating timestampJeff Layton
...otherwise, we end up with the list ordering wrong. Currently, it's not a problem since we skip RC_INPROG entries, but keeping the ordering strict will be necessary for a later patch that adds a cache cleaner. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: break out hashtable search into separate functionJeff Layton
Later, we'll need more than one call site for this, so break it out into a new function. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: clean up and clarify the cache expiration codeJeff Layton
Add a preprocessor constant for the expiry time of cache entries, and move the test for an expired entry into a function. Note that the current code does not test for RC_INPROG. It just assumes that it won't take more than 2 minutes to fill out an in-progress entry. I'm not sure how valid that assumption is though, so let's just ensure that we never consider an RC_INPROG entry to be expired. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: remove redundant test from nfsd_reply_cache_freeJeff Layton
Entries can only get a c_type of RC_REPLBUFF iff they are RC_DONE. Therefore the test for RC_DONE isn't necessary here. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: add alloc and free functions for DRC entriesJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: create a dedicated slabcache for DRC entriesJeff Layton
Currently we use kmalloc() which wastes a little bit of memory on each allocation since it's a power of 2 allocator. Since we're allocating a 1024 of these now, and may need even more later, let's create a new slabcache for them. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: remove unneeded spinlock in nfsd_cache_updateJeff Layton
The locking rules for cache entries say that locking the cache_lock isn't needed if you're just touching the current entry. Earlier in this function we set rp->c_state to RC_UNUSED without any locking, so I believe it's ok to do the same here. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-04nfsd: fix IPv6 address handling in the DRCJeff Layton
Currently, it only stores the first 16 bytes of any address. struct sockaddr_in6 is 28 bytes however, so we're currently ignoring the last 12 bytes of the address. Expand the c_addr field to a sockaddr_in6, and cast it to a sockaddr_in as necessary. Also fix the comparitor to use the existing RPC helpers for this. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>