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2020-03-27xfs: don't write a corrupt unmount record to force summary counter recalcDarrick J. Wong
In commit f467cad95f5e3, I added the ability to force a recalculation of the filesystem summary counters if they seemed incorrect. This was done (not entirely correctly) by tweaking the log code to write an unmount record without the UMOUNT_TRANS flag set. At next mount, the log recovery code will fail to find the unmount record and go into recovery, which triggers the recalculation. What actually gets written to the log is what ought to be an unmount record, but without any flags set to indicate what kind of record it actually is. This worked to trigger the recalculation, but we shouldn't write bogus log records when we could simply write nothing. Fixes: f467cad95f5e3 ("xfs: force summary counter recalc at next mount") Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-03-27xfs: factor inode lookup from xfs_ifree_clusterDave Chinner
There's lots of indent in this code which makes it a bit hard to follow. We are also going to completely rework the inode lookup code as part of the inode reclaim rework, so factor out the inode lookup code from the inode cluster freeing code. Based on prototype code from Christoph Hellwig. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: tail updates only need to occur when LSN changesDave Chinner
We currently wake anything waiting on the log tail to move whenever the log item at the tail of the log is removed. Historically this was fine behaviour because there were very few items at any given LSN. But with delayed logging, there may be thousands of items at any given LSN, and we can't move the tail until they are all gone. Hence if we are removing them in near tail-first order, we might be waking up processes waiting on the tail LSN to change (e.g. log space waiters) repeatedly without them being able to make progress. This also occurs with the new sync push waiters, and can result in thousands of spurious wakeups every second when under heavy direct reclaim pressure. To fix this, check that the tail LSN has actually changed on the AIL before triggering wakeups. This will reduce the number of spurious wakeups when doing bulk AIL removal and make this code much more efficient. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: factor common AIL item deletion codeDave Chinner
Factor the common AIL deletion code that does all the wakeups into a helper so we only have one copy of this somewhat tricky code to interface with all the wakeups necessary when the LSN of the log tail changes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: correctly acount for reclaimable slabsDave Chinner
The XFS inode item slab actually reclaimed by inode shrinker callbacks from the memory reclaim subsystem. These should be marked as reclaimable so the mm subsystem has the full picture of how much memory it can actually reclaim from the XFS slab caches. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: Improve metadata buffer reclaim accountabilityDave Chinner
The buffer cache shrinker frees more than just the xfs_buf slab objects - it also frees the pages attached to the buffers. Make sure the memory reclaim code accounts for this memory being freed correctly, similar to how the inode shrinker accounts for pages freed from the page cache due to mapping invalidation. We also need to make sure that the mm subsystem knows these are reclaimable objects. We provide the memory reclaim subsystem with a a shrinker to reclaim xfs_bufs, so we should really mark the slab that way. We also have a lot of xfs_bufs in a busy system, spread them around like we do inodes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: don't allow log IO to be throttledDave Chinner
Running metadata intensive workloads, I've been seeing the AIL pushing getting stuck on pinned buffers and triggering log forces. The log force is taking a long time to run because the log IO is getting throttled by wbt_wait() - the block layer writeback throttle. It's being throttled because there is a huge amount of metadata writeback going on which is filling the request queue. IOWs, we have a priority inversion problem here. Mark the log IO bios with REQ_IDLE so they don't get throttled by the block layer writeback throttle. When we are forcing the CIL, we are likely to need to to tens of log IOs, and they are issued as fast as they can be build and IO completed. Hence REQ_IDLE is appropriate - it's an indication that more IO will follow shortly. And because we also set REQ_SYNC, the writeback throttle will now treat log IO the same way it treats direct IO writes - it will not throttle them at all. Hence we solve the priority inversion problem caused by the writeback throttle being unable to distinguish between high priority log IO and background metadata writeback. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: Throttle commits on delayed background CIL pushDave Chinner
In certain situations the background CIL push can be indefinitely delayed. While we have workarounds from the obvious cases now, it doesn't solve the underlying issue. This issue is that there is no upper limit on the CIL where we will either force or wait for a background push to start, hence allowing the CIL to grow without bound until it consumes all log space. To fix this, add a new wait queue to the CIL which allows background pushes to wait for the CIL context to be switched out. This happens when the push starts, so it will allow us to block incoming transaction commit completion until the push has started. This will only affect processes that are running modifications, and only when the CIL threshold has been significantly overrun. This has no apparent impact on performance, and doesn't even trigger until over 45 million inodes had been created in a 16-way fsmark test on a 2GB log. That was limiting at 64MB of log space used, so the active CIL size is only about 3% of the total log in that case. The concurrent removal of those files did not trigger the background sleep at all. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: Lower CIL flush limit for large logsDave Chinner
The current CIL size aggregation limit is 1/8th the log size. This means for large logs we might be aggregating at least 250MB of dirty objects in memory before the CIL is flushed to the journal. With CIL shadow buffers sitting around, this means the CIL is often consuming >500MB of temporary memory that is all allocated under GFP_NOFS conditions. Flushing the CIL can take some time to do if there is other IO ongoing, and can introduce substantial log force latency by itself. It also pins the memory until the objects are in the AIL and can be written back and reclaimed by shrinkers. Hence this threshold also tends to determine the minimum amount of memory XFS can operate in under heavy modification without triggering the OOM killer. Modify the CIL space limit to prevent such huge amounts of pinned metadata from aggregating. We can have 2MB of log IO in flight at once, so limit aggregation to 16x this size. This threshold was chosen as it little impact on performance (on 16-way fsmark) or log traffic but pins a lot less memory on large logs especially under heavy memory pressure. An aggregation limit of 8x had 5-10% performance degradation and a 50% increase in log throughput for the same workload, so clearly that was too small for highly concurrent workloads on large logs. This was found via trace analysis of AIL behaviour. e.g. insertion from a single CIL flush: xfs_ail_insert: old lsn 0/0 new lsn 1/3033090 type XFS_LI_INODE flags IN_AIL $ grep xfs_ail_insert /mnt/scratch/s.t |grep "new lsn 1/3033090" |wc -l 1721823 $ So there were 1.7 million objects inserted into the AIL from this CIL checkpoint, the first at 2323.392108, the last at 2325.667566 which was the end of the trace (i.e. it hadn't finished). Clearly a major problem. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: remove some stale comments from the log codeDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: refactor unmount record writingDave Chinner
Separate out the unmount record writing from the rest of the ticket and log state futzing necessary to make it work. This is a no-op, just makes the code cleaner and places the unmount record formatting and writing alongside the commit record formatting and writing code. We can also get rid of the ticket flag clearing before the xlog_write() call because it no longer cares about the state of XLOG_TIC_INITED. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: merge xlog_commit_record with xlog_write_doneDave Chinner
xlog_write_done() is just a thin wrapper around xlog_commit_record(), so they can be merged together easily. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: split xlog_ticket_doneChristoph Hellwig
Remove xlog_ticket_done and just call the renamed low-level helpers for ungranting or regranting log space directly. To make that a little the reference put on the ticket and all tracing is moved into the actual helpers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: kill XLOG_TIC_INITEDDave Chinner
It is not longer used or checked by anything, so remove the last traces from the log ticket code. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: refactor and split xfs_log_done()Dave Chinner
xfs_log_done() does two separate things. Firstly, it triggers commit records to be written for permanent transactions, and secondly it releases or regrants transaction reservation space. Since delayed logging was introduced, transactions no longer write directly to the log, hence they never have the XLOG_TIC_INITED flag cleared on them. Hence transactions never write commit records to the log and only need to modify reservation space. Split up xfs_log_done into two parts, and only call the parts of the operation needed for the context xfs_log_done() is currently being called from. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: re-order initial space accounting checks in xlog_writeDave Chinner
Commit and unmount records records do not need start records to be written, so rearrange the logic in xlog_write() to remove the need to check for XLOG_TIC_INITED to determine if we should account for the space used by a start record. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: don't try to write a start record into every iclogDave Chinner
The xlog_write() function iterates over iclogs until it completes writing all the log vectors passed in. The ticket tracks whether a start record has been written or not, so only the first iclog gets a start record. We only ever pass single use tickets to xlog_write() so we only ever need to write a start record once per xlog_write() call. Hence we don't need to store whether we should write a start record in the ticket as the callers provide all the information we need to determine if a start record should be written. For the moment, we have to ensure that we clear the XLOG_TIC_INITED appropriately so the code in xfs_log_done() still works correctly for committing transactions. (darrick: Note the slight behavior change that we always deduct the size of the op header from the ticket, even for unmount records) Signed-off-by: Dave Chinner <dchinner@redhat.com> [hch: pass an explicit need_start_rec argument] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-27xfs: validate the realtime geometry in xfs_validate_sb_commonDarrick J. Wong
Validate the geometry of the realtime geometry when we mount the filesystem, so that we don't abruptly shut down the filesystem later on. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-03-27io_uring: cleanup io_alloc_async_ctx()Xiaoguang Wang
Cleanup io_alloc_async_ctx() a bit, add a new __io_alloc_async_ctx(), so io_setup_async_rw() won't need to check whether async_ctx is true or false again. Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-279p: read only once on O_NONBLOCKSergey Alirzaev
A proper way to handle O_NONBLOCK would be making the requests and responses happen asynchronously, but this would require serious code refactoring. Link: http://lkml.kernel.org/r/20200205003457.24340-2-l29ah@cock.li Signed-off-by: Sergey Alirzaev <l29ah@cock.li> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2020-03-279p: Remove unneeded semicolonzhengbin
Fixes coccicheck warning: fs/9p/vfs_inode.c:146:3-4: Unneeded semicolon Link: http://lkml.kernel.org/r/1576752517-58292-1-git-send-email-zhengbin13@huawei.com Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2020-03-279p: Fix Kconfig indentationKrzysztof Kozlowski
Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Link: http://lkml.kernel.org/r/20191120134340.16770-1-krzk@kernel.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2020-03-26afs: Fix unpinned address list during probingDavid Howells
When it's probing all of a fileserver's interfaces to find which one is best to use, afs_do_probe_fileserver() takes a lock on the server record and notes the pointer to the address list. It doesn't, however, pin the address list, so as soon as it drops the lock, there's nothing to stop the address list from being freed under us. Fix this by taking a ref on the address list inside the locked section and dropping it at the end of the function. Fixes: 3bf0fb6f33dd ("afs: Probe multiple fileservers simultaneously") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-26Merge tag 'ceph-for-5.6-rc8' of git://github.com/ceph/ceph-clientLinus Torvalds
Pull ceph fixes from Ilya Dryomov: "A patch for a rather old regression in fullness handling and two memory leak fixes, marked for stable" * tag 'ceph-for-5.6-rc8' of git://github.com/ceph/ceph-client: ceph: fix memory leak in ceph_cleanup_snapid_map() libceph: fix alloc_msg_with_page_vector() memory leaks ceph: check POOL_FLAG_FULL/NEARFULL in addition to OSDMAP_FULL/NEARFULL
2020-03-26xfs: prohibit fs freezing when using empty transactionsDarrick J. Wong
I noticed that fsfreeze can take a very long time to freeze an XFS if there happens to be a GETFSMAP caller running in the background. I also happened to notice the following in dmesg: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 43492 at fs/xfs/xfs_super.c:853 xfs_quiesce_attr+0x83/0x90 [xfs] Modules linked in: xfs libcrc32c ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 ip_set_hash_ip ip_set_hash_net xt_tcpudp xt_set ip_set_hash_mac ip_set nfnetlink ip6table_filter ip6_tables bfq iptable_filter sch_fq_codel ip_tables x_tables nfsv4 af_packet [last unloaded: xfs] CPU: 2 PID: 43492 Comm: xfs_io Not tainted 5.6.0-rc4-djw #rc4 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014 RIP: 0010:xfs_quiesce_attr+0x83/0x90 [xfs] Code: 7c 07 00 00 85 c0 75 22 48 89 df 5b e9 96 c1 00 00 48 c7 c6 b0 2d 38 a0 48 89 df e8 57 64 ff ff 8b 83 7c 07 00 00 85 c0 74 de <0f> 0b 48 89 df 5b e9 72 c1 00 00 66 90 0f 1f 44 00 00 41 55 41 54 RSP: 0018:ffffc900030f3e28 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88802ac54000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff81e4a6f0 RDI: 00000000ffffffff RBP: ffff88807859f070 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000010 R12: 0000000000000000 R13: ffff88807859f388 R14: ffff88807859f4b8 R15: ffff88807859f5e8 FS: 00007fad1c6c0fc0(0000) GS:ffff88807e000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0c7d237000 CR3: 0000000077f01003 CR4: 00000000001606a0 Call Trace: xfs_fs_freeze+0x25/0x40 [xfs] freeze_super+0xc8/0x180 do_vfs_ioctl+0x70b/0x750 ? __fget_files+0x135/0x210 ksys_ioctl+0x3a/0xb0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x1a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe These two things appear to be related. The assertion trips when another thread initiates a fsmap request (which uses an empty transaction) after the freezer waited for m_active_trans to hit zero but before the the freezer executes the WARN_ON just prior to calling xfs_log_quiesce. The lengthy delays in freezing happen because the freezer calls xfs_wait_buftarg to clean out the buffer lru list. Meanwhile, the GETFSMAP caller is continuing to grab and release buffers, which means that it can take a very long time for the buffer lru list to empty out. We fix both of these races by calling sb_start_write to obtain freeze protection while using empty transactions for GETFSMAP and for metadata scrubbing. The other two users occur during mount, during which time we cannot fs freeze. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-03-26xfs: shutdown on failure to add page to log bioBrian Foster
If the bio_add_page() call fails, we proceed to write out a partially constructed log buffer. This corrupts the physical log such that log recovery is not possible. Worse, persistent occurrences of this error eventually lead to a BUG_ON() failure in bio_split() as iclogs wrap the end of the physical log, which triggers log recovery on subsequent mount. Rather than warn about writing out a corrupted log buffer, shutdown the fs as is done for any log I/O related error. This preserves the consistency of the physical log such that log recovery succeeds on a subsequent mount. Note that this was observed on a 64k page debug kernel without upstream commit 59bb47985c1d ("mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)"), which demonstrated frequent iclog bio overflows due to unaligned (slab allocated) iclog data buffers. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-26xfs: directory bestfree check should release buffersDarrick J. Wong
When we're checking bestfree information in directory blocks, always drop the block buffer at the end of the function. We should always release resources when we're done using them. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-03-26xfs: drop all altpath buffers at the end of the sibling checkDarrick J. Wong
The dirattr btree checking code uses the altpath substructure of the dirattr state structure to check the sibling pointers of dir/attr tree blocks. At the end of sibling checks, xfs_da3_path_shift could have changed multiple levels of buffer pointers in the altpath structure. Although we release the leaf level buffer, this isn't enough -- we also need to release the node buffers that are unique to the altpath. Not releasing all of the altpath buffers leaves them locked to the transaction. This is suboptimal because we should release resources when we don't need them anymore. Fix the function to loop all levels of the altpath, and fix the return logic so that we always run the loop. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-03-26xfs: preserve default grace interval during quotacheckDarrick J. Wong
When quotacheck runs, it zeroes all the timer fields in every dquot. Unfortunately, it also does this to the root dquot, which erases any preconfigured grace intervals and warning limits that the administrator may have set. Worse yet, the incore copies of those variables remain set. This cache coherence problem manifests itself as the grace interval mysteriously being reset back to the defaults at the /next/ mount. Fix it by not resetting the root disk dquot's timer and warning fields. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-03-26ext4: disable dioread_nolock whenever delayed allocation is disabledEric Whitney
The patch "ext4: make dioread_nolock the default" (244adf6426ee) causes generic/422 to fail when run in kvm-xfstests' ext3conv test case. This applies both the dioread_nolock and nodelalloc mount options, a combination not previously tested by kvm-xfstests. The failure occurs because the dioread_nolock code path splits a previously fallocated multiblock extent into a series of single block extents when overwriting a portion of that extent. That causes allocation of an extent tree leaf node and a reshuffling of extents. Once writeback is completed, the individual extents are recombined into a single extent, the extent is moved again, and the leaf node is deleted. The difference in block utilization before and after writeback due to the leaf node triggers the failure. The original reason for this behavior was to avoid ENOSPC when handling I/O completions during writeback in the dioread_nolock code paths when delayed allocation is disabled. It may no longer be necessary, because code was added in the past to reserve extra space to solve this problem when delayed allocation is enabled, and this code may also apply when delayed allocation is disabled. Until this can be verified, don't use the dioread_nolock code paths if delayed allocation is disabled. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Link: https://lore.kernel.org/r/20200319150028.24592-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-03-26ext4: do not commit super on read-only bdevEric Sandeen
Under some circumstances we may encounter a filesystem error on a read-only block device, and if we try to save the error info to the superblock and commit it, we'll wind up with a noisy error and backtrace, i.e.: [ 3337.146838] EXT4-fs error (device pmem1p2): ext4_get_journal_inode:4634: comm mount: inode #0: comm mount: iget: illegal inode # ------------[ cut here ]------------ generic_make_request: Trying to write to read-only block-device pmem1p2 (partno 2) WARNING: CPU: 107 PID: 115347 at block/blk-core.c:788 generic_make_request_checks+0x6b4/0x7d0 ... To avoid this, commit the error info in the superblock only if the block device is writable. Reported-by: Ritesh Harjani <riteshh@linux.ibm.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/4b6e774d-cc00-3469-7abb-108eb151071a@sandeen.net Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-03-26ext4: avoid ENOSPC when avoiding to reuse recently deleted inodesJan Kara
When ext4 is running on a filesystem without a journal, it tries not to reuse recently deleted inodes to provide better chances for filesystem recovery in case of crash. However this logic forbids reuse of freed inodes for up to 5 minutes and especially for filesystems with smaller number of inodes can lead to ENOSPC errors returned when allocating new inodes. Fix the problem by allowing to reuse recently deleted inode if there's no other inode free in the scanned range. Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200318121317.31941-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-03-26ext4: unregister sysfs path before destroying jbd2 journalRitesh Harjani
Call ext4_unregister_sysfs(), before destroying jbd2 journal, since below might cause, NULL pointer dereference issue. This got reported with LTP tests. ext4_put_super() cat /sys/fs/ext4/loop2/journal_task | ext4_attr_show(); ext4_jbd2_journal_destroy(); | | journal_task_show() | | | task_pid_vnr(NULL); sbi->s_journal = NULL; Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200318061301.4320-1-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-03-26ext4: check for non-zero journal inum in ext4_calculate_overheadRitesh Harjani
While calculating overhead for internal journal, also check that j_inum shouldn't be 0. Otherwise we get below error with xfstests generic/050 with external journal (XXX_LOGDEV config) enabled. It could be simply reproduced with loop device with an external journal and marking blockdev as RO before mounting. [ 3337.146838] EXT4-fs error (device pmem1p2): ext4_get_journal_inode:4634: comm mount: inode #0: comm mount: iget: illegal inode # ------------[ cut here ]------------ generic_make_request: Trying to write to read-only block-device pmem1p2 (partno 2) WARNING: CPU: 107 PID: 115347 at block/blk-core.c:788 generic_make_request_checks+0x6b4/0x7d0 CPU: 107 PID: 115347 Comm: mount Tainted: G L --------- -t - 4.18.0-167.el8.ppc64le #1 NIP: c0000000006f6d44 LR: c0000000006f6d40 CTR: 0000000030041dd4 <...> NIP [c0000000006f6d44] generic_make_request_checks+0x6b4/0x7d0 LR [c0000000006f6d40] generic_make_request_checks+0x6b0/0x7d0 <...> Call Trace: generic_make_request_checks+0x6b0/0x7d0 (unreliable) generic_make_request+0x3c/0x420 submit_bio+0xd8/0x200 submit_bh_wbc+0x1e8/0x250 __sync_dirty_buffer+0xd0/0x210 ext4_commit_super+0x310/0x420 [ext4] __ext4_error+0xa4/0x1e0 [ext4] __ext4_iget+0x388/0xe10 [ext4] ext4_get_journal_inode+0x40/0x150 [ext4] ext4_calculate_overhead+0x5a8/0x610 [ext4] ext4_fill_super+0x3188/0x3260 [ext4] mount_bdev+0x778/0x8f0 ext4_mount+0x28/0x50 [ext4] mount_fs+0x74/0x230 vfs_kern_mount.part.6+0x6c/0x250 do_mount+0x2fc/0x1280 sys_mount+0x158/0x180 system_call+0x5c/0x70 EXT4-fs (pmem1p2): no journal found EXT4-fs (pmem1p2): can't get journal size EXT4-fs (pmem1p2): mounted filesystem without journal. Opts: dax,norecovery Fixes: 3c816ded78bb ("ext4: use journal inode to determine journal overhead") Reported-by: Harish Sriram <harish@linux.ibm.com> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200316093038.25485-1-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-03-26pNFS: Add a helper to allocate the array of bucketsTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-26NFS/pNFS: Refactor pnfs_generic_commit_pagelist()Trond Myklebust
Refactor pnfs_generic_commit_pagelist() to simplify the conversion to layout segment based commit lists. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-26pNFS/flexfiles: Simplify allocation of the mirror arrayTrond Myklebust
Just allocate the array at the end of the layout segment structure, instead of allocating it as a separate array of pointers. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Overlapping header include additions in macsec.c A bug fix in 'net' overlapping with the removal of 'version' string in ena_netdev.c Overlapping test additions in selftests Makefile Overlapping PCI ID table adjustments in iwlwifi driver. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-25fanotify: report name info for FAN_DIR_MODIFY eventAmir Goldstein
Report event FAN_DIR_MODIFY with name in a variable length record similar to how fid's are reported. With name info reporting implemented, setting FAN_DIR_MODIFY in mark mask is now allowed. When events are reported with name, the reported fid identifies the directory and the name follows the fid. The info record type for this event info is FAN_EVENT_INFO_TYPE_DFID_NAME. For now, all reported events have at most one info record which is either FAN_EVENT_INFO_TYPE_FID or FAN_EVENT_INFO_TYPE_DFID_NAME (for FAN_DIR_MODIFY). Later on, events "on child" will report both records. There are several ways that an application can use this information: 1. When watching a single directory, the name is always relative to the watched directory, so application need to fstatat(2) the name relative to the watched directory. 2. When watching a set of directories, the application could keep a map of dirfd for all watched directories and hash the map by fid obtained with name_to_handle_at(2). When getting a name event, the fid in the event info could be used to lookup the base dirfd in the map and then call fstatat(2) with that dirfd. 3. When watching a filesystem (FAN_MARK_FILESYSTEM) or a large set of directories, the application could use open_by_handle_at(2) with the fid in event info to obtain dirfd for the directory where event happened and call fstatat(2) with this dirfd. The last option scales better for a large number of watched directories. The first two options may be available in the future also for non privileged fanotify watchers, because open_by_handle_at(2) requires the CAP_DAC_READ_SEARCH capability. Link: https://lore.kernel.org/r/20200319151022.31456-15-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25fanotify: record name info for FAN_DIR_MODIFY eventAmir Goldstein
For FAN_DIR_MODIFY event, allocate a variable size event struct to store the dir entry name along side the directory file handle. At this point, name info reporting is not yet implemented, so trying to set FAN_DIR_MODIFY in mark mask will return -EINVAL. Link: https://lore.kernel.org/r/20200319151022.31456-14-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix deadlock in bpf_send_signal() from Yonghong Song. 2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan. 3) Add missing locking in iwlwifi mvm code, from Avraham Stern. 4) Fix MSG_WAITALL handling in rxrpc, from David Howells. 5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong Wang. 6) Fix producer race condition in AF_PACKET, from Willem de Bruijn. 7) cls_route removes the wrong filter during change operations, from Cong Wang. 8) Reject unrecognized request flags in ethtool netlink code, from Michal Kubecek. 9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from Doug Berger. 10) Don't leak ct zone template in act_ct during replace, from Paul Blakey. 11) Fix flushing of offloaded netfilter flowtable flows, also from Paul Blakey. 12) Fix throughput drop during tx backpressure in cxgb4, from Rahul Lakkireddy. 13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric Dumazet. 14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well, also from Eric Dumazet. 15) Restrict macsec to ethernet devices, from Willem de Bruijn. 16) Fix reference leak in some ethtool *_SET handlers, from Michal Kubecek. 17) Fix accidental disabling of MSI for some r8169 chips, from Heiner Kallweit. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits) net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build net: ena: Add PCI shutdown handler to allow safe kexec selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED selftests/net: add missing tests to Makefile r8169: re-enable MSI on RTL8168c net: phy: mdio-bcm-unimac: Fix clock handling cxgb4/ptp: pass the sign of offset delta in FW CMD net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop net: cbs: Fix software cbs to consider packet sending time net/mlx5e: Do not recover from a non-fatal syndrome net/mlx5e: Fix ICOSQ recovery flow with Striding RQ net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset net/mlx5e: Enhance ICOSQ WQE info fields net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure selftests: netfilter: add nfqueue test case netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress netfilter: nft_fwd_netdev: validate family and chain type netfilter: nft_set_rbtree: Detect partial overlaps on insertion netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start() netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion ...
2020-03-25Merge tag 'zonefs-5.6-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs Pull zonefs fix from Damien Le Moal: "A single fix from me to correctly handle the size of read-only zone files" * tag 'zonefs-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs: zonfs: Fix handling of read-only zones
2020-03-25block: move the part_stat* helpers from genhd.h to a new headerChristoph Hellwig
These macros are just used by a few files. Move them out of genhd.h, which is included everywhere into a new standalone header. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-25block: move guard_bio_eod to bio.cChristoph Hellwig
This is bio layer functionality and not related to buffer heads. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-25btrfs: fix missing semaphore unlock in btrfs_sync_fileRobbie Ko
Ordered ops are started twice in sync file, once outside of inode mutex and once inside, taking the dio semaphore. There was one error path missing the semaphore unlock. Fixes: aab15e8ec2576 ("Btrfs: fix rare chances for data loss when doing a fast fsync") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Robbie Ko <robbieko@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> [ add changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-25btrfs: use nofs allocations for running delayed itemsJosef Bacik
Zygo reported the following lockdep splat while testing the balance patches ====================================================== WARNING: possible circular locking dependency detected 5.6.0-c6f0579d496a+ #53 Not tainted ------------------------------------------------------ kswapd0/1133 is trying to acquire lock: ffff888092f622c0 (&delayed_node->mutex){+.+.}, at: __btrfs_release_delayed_node+0x7c/0x5b0 but task is already holding lock: ffffffff8fc5f860 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}: fs_reclaim_acquire.part.91+0x29/0x30 fs_reclaim_acquire+0x19/0x20 kmem_cache_alloc_trace+0x32/0x740 add_block_entry+0x45/0x260 btrfs_ref_tree_mod+0x6e2/0x8b0 btrfs_alloc_tree_block+0x789/0x880 alloc_tree_block_no_bg_flush+0xc6/0xf0 __btrfs_cow_block+0x270/0x940 btrfs_cow_block+0x1ba/0x3a0 btrfs_search_slot+0x999/0x1030 btrfs_insert_empty_items+0x81/0xe0 btrfs_insert_delayed_items+0x128/0x7d0 __btrfs_run_delayed_items+0xf4/0x2a0 btrfs_run_delayed_items+0x13/0x20 btrfs_commit_transaction+0x5cc/0x1390 insert_balance_item.isra.39+0x6b2/0x6e0 btrfs_balance+0x72d/0x18d0 btrfs_ioctl_balance+0x3de/0x4c0 btrfs_ioctl+0x30ab/0x44a0 ksys_ioctl+0xa1/0xe0 __x64_sys_ioctl+0x43/0x50 do_syscall_64+0x77/0x2c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&delayed_node->mutex){+.+.}: __lock_acquire+0x197e/0x2550 lock_acquire+0x103/0x220 __mutex_lock+0x13d/0xce0 mutex_lock_nested+0x1b/0x20 __btrfs_release_delayed_node+0x7c/0x5b0 btrfs_remove_delayed_node+0x49/0x50 btrfs_evict_inode+0x6fc/0x900 evict+0x19a/0x2c0 dispose_list+0xa0/0xe0 prune_icache_sb+0xbd/0xf0 super_cache_scan+0x1b5/0x250 do_shrink_slab+0x1f6/0x530 shrink_slab+0x32e/0x410 shrink_node+0x2a5/0xba0 balance_pgdat+0x4bd/0x8a0 kswapd+0x35a/0x800 kthread+0x1e9/0x210 ret_from_fork+0x3a/0x50 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&delayed_node->mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/1133: #0: ffffffff8fc5f860 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffff8fc380d8 (shrinker_rwsem){++++}, at: shrink_slab+0x1e8/0x410 #2: ffff8881e0e6c0e8 (&type->s_umount_key#42){++++}, at: trylock_super+0x1b/0x70 stack backtrace: CPU: 2 PID: 1133 Comm: kswapd0 Not tainted 5.6.0-c6f0579d496a+ #53 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack+0xc1/0x11a print_circular_bug.isra.38.cold.57+0x145/0x14a check_noncircular+0x2a9/0x2f0 ? print_circular_bug.isra.38+0x130/0x130 ? stack_trace_consume_entry+0x90/0x90 ? save_trace+0x3cc/0x420 __lock_acquire+0x197e/0x2550 ? btrfs_inode_clear_file_extent_range+0x9b/0xb0 ? register_lock_class+0x960/0x960 lock_acquire+0x103/0x220 ? __btrfs_release_delayed_node+0x7c/0x5b0 __mutex_lock+0x13d/0xce0 ? __btrfs_release_delayed_node+0x7c/0x5b0 ? __asan_loadN+0xf/0x20 ? pvclock_clocksource_read+0xeb/0x190 ? __btrfs_release_delayed_node+0x7c/0x5b0 ? mutex_lock_io_nested+0xc20/0xc20 ? __kasan_check_read+0x11/0x20 ? check_chain_key+0x1e6/0x2e0 mutex_lock_nested+0x1b/0x20 ? mutex_lock_nested+0x1b/0x20 __btrfs_release_delayed_node+0x7c/0x5b0 btrfs_remove_delayed_node+0x49/0x50 btrfs_evict_inode+0x6fc/0x900 ? btrfs_setattr+0x840/0x840 ? do_raw_spin_unlock+0xa8/0x140 evict+0x19a/0x2c0 dispose_list+0xa0/0xe0 prune_icache_sb+0xbd/0xf0 ? invalidate_inodes+0x310/0x310 super_cache_scan+0x1b5/0x250 do_shrink_slab+0x1f6/0x530 shrink_slab+0x32e/0x410 ? do_shrink_slab+0x530/0x530 ? do_shrink_slab+0x530/0x530 ? __kasan_check_read+0x11/0x20 ? mem_cgroup_protected+0x13d/0x260 shrink_node+0x2a5/0xba0 balance_pgdat+0x4bd/0x8a0 ? mem_cgroup_shrink_node+0x490/0x490 ? _raw_spin_unlock_irq+0x27/0x40 ? finish_task_switch+0xce/0x390 ? rcu_read_lock_bh_held+0xb0/0xb0 kswapd+0x35a/0x800 ? _raw_spin_unlock_irqrestore+0x4c/0x60 ? balance_pgdat+0x8a0/0x8a0 ? finish_wait+0x110/0x110 ? __kasan_check_read+0x11/0x20 ? __kthread_parkme+0xc6/0xe0 ? balance_pgdat+0x8a0/0x8a0 kthread+0x1e9/0x210 ? kthread_create_worker_on_cpu+0xc0/0xc0 ret_from_fork+0x3a/0x50 This is because we hold that delayed node's mutex while doing tree operations. Fix this by just wrapping the searches in nofs. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-25proc: io_accounting: Use new infrastructure to fix deadlocks in execveBernd Edlinger
This changes do_io_accounting to use the new exec_update_mutex instead of cred_guard_mutex. This fixes possible deadlocks when the trace is accessing /proc/$pid/io for instance. This should be safe, as the credentials are only used for reading. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25proc: Use new infrastructure to fix deadlocks in execveBernd Edlinger
This changes lock_trace to use the new exec_update_mutex instead of cred_guard_mutex. This fixes possible deadlocks when the trace is accessing /proc/$pid/stack for instance. This should be safe, as the credentials are only used for reading, and task->mm is updated on execve under the new exec_update_mutex. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25exec: Add exec_update_mutex to replace cred_guard_mutexEric W. Biederman
The cred_guard_mutex is problematic as it is held over possibly indefinite waits for userspace. The possible indefinite waits for userspace that I have identified are: The cred_guard_mutex is held in PTRACE_EVENT_EXIT waiting for the tracer. The cred_guard_mutex is held over "put_user(0, tsk->clear_child_tid)" in exit_mm(). The cred_guard_mutex is held over "get_user(futex_offset, ...") in exit_robust_list. The cred_guard_mutex held over copy_strings. The functions get_user and put_user can trigger a page fault which can potentially wait indefinitely in the case of userfaultfd or if userspace implements part of the page fault path. In any of those cases the userspace process that the kernel is waiting for might make a different system call that winds up taking the cred_guard_mutex and result in deadlock. Holding a mutex over any of those possibly indefinite waits for userspace does not appear necessary. Add exec_update_mutex that will just cover updating the process during exec where the permissions and the objects pointed to by the task struct may be out of sync. The plan is to switch the users of cred_guard_mutex to exec_update_mutex one by one. This lets us move forward while still being careful and not introducing any regressions. Link: https://lore.kernel.org/lkml/20160921152946.GA24210@dhcp22.suse.cz/ Link: https://lore.kernel.org/lkml/AM6PR03MB5170B06F3A2B75EFB98D071AE4E60@AM6PR03MB5170.eurprd03.prod.outlook.com/ Link: https://lore.kernel.org/linux-fsdevel/20161102181806.GB1112@redhat.com/ Link: https://lore.kernel.org/lkml/20160923095031.GA14923@redhat.com/ Link: https://lore.kernel.org/lkml/20170213141452.GA30203@redhat.com/ Ref: 45c1a159b85b ("Add PTRACE_O_TRACEVFORKDONE and PTRACE_O_TRACEEXIT facilities.") Ref: 456f17cd1a28 ("[PATCH] user-vm-unlock-2.5.31-A2") Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25exec: Move exec_mmap right after de_thread in flush_old_execEric W. Biederman
I have read through the code in exec_mmap and I do not see anything that depends on sighand or the sighand lock, or on signals in anyway so this should be safe. This rearrangement of code has two significant benefits. It makes the determination of passing the point of no return by testing bprm->mm accurate. All failures prior to that point in flush_old_exec are either truly recoverable or they are fatal. Further this consolidates all of the possible indefinite waits for userspace together at the top of flush_old_exec. The possible wait for a ptracer on PTRACE_EVENT_EXIT, the possible wait for a page fault to be resolved in clear_child_tid, and the possible wait for a page fault in exit_robust_list. This consolidation allows the creation of a mutex to replace cred_guard_mutex that is not held over possible indefinite userspace waits. Which will allow removing deadlock scenarios from the kernel. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>