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* gfs2: move check_journal_clean to util.c for future useBob Peterson2020-02-103-42/+46
| | | | | | | | | Before this patch function check_journal_clean was in ops_fstype.c. This patch moves it to util.c so we can make use of it elsewhere in a future patch. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: Ignore dlm recovery requests if gfs2 is withdrawnBob Peterson2020-02-102-0/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a node fails, user space informs dlm of the node failure, and dlm instructs gfs2 on the surviving nodes to perform journal recovery. It does this by calling various callback functions in lock_dlm.c. To mark its progress, it keeps generation numbers and recover bits in a dlm "control" lock lvb, which is seen by all nodes to determine which journals need to be replayed. The gfs2 on all nodes get the same recovery requests from dlm, so they all try to do the recovery, but only one will be granted the exclusive lock on the journal. The others fail with a "Busy" message on their "try lock." However, when a node is withdrawn, it cannot safely do any recovery or replay any journals. To make matters worse, gfs2 might withdraw as a result of attempting recovery. For example, this might happen if the device goes offline, or if an hba fails. But in today's gfs2 code, it doesn't check for being withdrawn at any step in the recovery process. What's worse is that these callbacks from dlm have no return code, so there is no way to indicate failure back to dlm. We can send a "Recovery failed" uevent eventually, but that tells user space what happened, not dlm's kernel code. Before this patch, lock_dlm would perform its recovery steps but ignore the result, and eventually it would still update its generation number in the lvb, despite the fact that it may have withdrawn or encountered an error. The other nodes would then see the newer generation number in the lvb and conclude that they don't need to do recovery because the generation number is newer than the last one they saw. They think a different node has already recovered the journal. This patch adds checks to several of the callbacks used by dlm in its recovery state machine so that the functions are ignored and skipped if an io error has occurred or if the file system is withdrawn. That prevents the lvb bits from being updated, and therefore dlm and user space still see the need for recovery to take place. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: Only complain the first time an io error occurs in quota or logBob Peterson2020-02-102-4/+5
| | | | | | | | | | | | | | | | | | | | | | Before this patch, all io errors received by the quota daemon or the logd daemon would cause a complaint message to be issued, such as: gfs2: fsid=dm-13.0: Error 10 writing to journal, jid=0 This patch changes it so that the error message is only issued the first time the error is encountered. Also, before this patch function gfs2_end_log_write did not set the sd_log_error value, so log errors would not cause the file system to be withdrawn. This patch sets the error code so the file system is properly withdrawn if an io error is encountered writing to the journal. WARNING: This change in function breaks check xfstests generic/441 and causes it to fail: io errors writing to the log should cause a file system to be withdrawn, and no further operations are tolerated. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: log error reformBob Peterson2020-02-103-9/+16
| | | | | | | | | | | | | | | | | | Before this patch, gfs2 kept track of journal io errors in two places sd_log_error and the SDF_AIL1_IO_ERROR flag in sd_flags. This patch consolidates the two into sd_log_error so that it reflects the first error encountered writing to the journal. In future patches, we will take advantage of this by checking this value rather than having to check both when reacting to io errors. In addition, this fixes a tight loop in unmount: If buffers get on the ail1 list and an io error occurs elsewhere, the ail1 list would never be cleared because they were always busy. So unmount would hang, waiting for the ail1 list to empty. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: Rework how rgrp buffer_heads are managedBob Peterson2020-02-105-36/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch, the rgrp code had a serious problem related to how it managed buffer_heads for resource groups. The problem caused file system corruption, especially in cases of journal replay. When an rgrp glock was demoted to transfer ownership to a different cluster node, do_xmote() first calls rgrp_go_sync and then rgrp_go_inval, as expected. When it calls rgrp_go_sync, that called gfs2_rgrp_brelse() that dropped the buffer_head reference count. In most cases, the reference count went to zero, which is right. However, there were other places where the buffers are handled differently. After rgrp_go_sync, do_xmote called rgrp_go_inval which called gfs2_rgrp_brelse a second time, then rgrp_go_inval's call to truncate_inode_pages_range would get rid of the pages in memory, but only if the reference count drops to 0. Unfortunately, gfs2_rgrp_brelse was setting bi->bi_bh = NULL. So when rgrp_go_sync called gfs2_rgrp_brelse, it lost the pointer to the buffer_heads in cases where the reference count was still 1. Therefore, when rgrp_go_inval called gfs2_rgrp_brelse a second time, it failed the check for "if (bi->bi_bh)" and thus failed to call brelse a second time. Because of that, the reference count on those buffers sometimes failed to drop from 1 to 0. And that caused function truncate_inode_pages_range to keep the pages in page cache rather than freeing them. The next time the rgrp glock was acquired, the metadata read of the rgrp buffers re-used the pages in memory, which were now wrong because they were likely modified by the other node who acquired the glock in EX (which is why we demoted the glock). This re-use of the page cache caused corruption because changes made by the other nodes were never seen, so the bitmaps were inaccurate. For some reason, the problem became most apparent when journal replay forced the replay of rgrps in memory, which caused newer rgrp data to be overwritten by the older in-core pages. A big part of the problem was that the rgrp buffer were released in multiple places: The go_unlock function would release them when the glock was released rather than when the glock is demoted, which is clearly wrong because our intent was to cache them until the glock is demoted from SH or EX. This patch attempts to clean up the mess and make one consistent and centralized mechanism for managing the rgrp buffer_heads by implementing several changes: 1. It eliminates the call to gfs2_rgrp_brelse() from rgrp_go_sync. We don't want to release the buffers or zero the pointers when syncing for the reasons stated above. It only makes sense to release them when the glock is actually invalidated (go_inval). And when we do, then we set the bh pointers to NULL. 2. The go_unlock function (which was only used for rgrps) is eliminated, as we've talked about doing many times before. The go_unlock function was called too early in the glock dq process, and should not happen until the glock is invalidated. 3. It also eliminates the call to rgrp_brelse in gfs2_clear_rgrpd. That will now happen automatically when the rgrp glocks are demoted, and shouldn't happen any sooner or later than that. Instead, function gfs2_clear_rgrpd has been modified to demote the rgrp glocks, and therefore, free those pages, before the remaining glocks are culled by gfs2_gl_hash_clear. This prevents the gl_object from hanging around when the glocks are culled. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: clear ail1 list when gfs2 withdrawsBob Peterson2020-02-101-4/+13
| | | | | | | | | | | | | | | This patch fixes a bug in which function gfs2_log_flush can get into an infinite loop when a gfs2 file system is withdrawn. The problem is the infinite loop "for (;;)" in gfs2_log_flush which would never finish because the io error and subsequent withdraw prevented the items from being taken off the ail list. This patch tries to clean up the mess by allowing withdraw situations to move not-in-flight buffer_heads to the ail2 list, where they will be dealt with later. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: Introduce concept of a pending withdrawBob Peterson2020-02-104-21/+27
| | | | | | | | | | | | | | | | | | | | | | File system withdraws can be delayed when inconsistencies are discovered when we cannot withdraw immediately, for example, when critical spin_locks are held. But delaying the withdraw can cause gfs2 to ignore the error and keep running for a short period of time. For example, an rgrp glock may be dequeued and demoted while there are still buffers that haven't been properly revoked, due to io errors writing to the journal. This patch introduces a new concept of a pending withdraw, which means an inconsistency has been discovered and we need to withdraw at the earliest possible opportunity. In these cases, we aren't quite withdrawn yet, but we still need to not dequeue glocks and other critical things. If we dequeue the glocks and the withdraw results in our journal being replayed, the replay could overwrite data that's been modified by a different node that acquired the glock in the meantime. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: Return bool from gfs2_assert functionsAndreas Gruenbacher2020-02-102-25/+24
| | | | | | | | | | | | | The gfs2_assert functions only print messages when the filesystem hasn't been withdrawn yet, and they indicate whether or not they've printed something in their return value. However, none of the callers use that information, so simply return whether or not the assert has failed. (The gfs2_assert functions are still backwards; they return false when an assertion is true.) Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
* gfs2: Turn gfs2_consist into void functionsAndreas Gruenbacher2020-02-102-21/+15
| | | | | | | Change the various gfs2_consist functions to return void. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
* gfs2: Remove usused cluster_wide arguments of gfs2_consist functionsAndreas Gruenbacher2020-02-102-9/+9
| | | | | | | These arguments are always passed as 0, and they are never evaluated. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
* gfs2: Report errors before withdrawAndreas Gruenbacher2020-02-101-25/+23
| | | | | | | | | In gfs2_rgrp_verify and compute_bitstructs, make sure to report errors before withdrawing the filesystem: otherwise, when we withdraw first and withdraw is configured to panic, we'll never get to the error reporting. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
* gfs2: Split gfs2_lm_withdraw into two functionsAndreas Gruenbacher2020-02-105-70/+82
| | | | | | | | Split gfs2_lm_withdraw into a function that prints an error message and a function that withdraws the filesystem. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
* gfs2: fix O_SYNC write handlingAndreas Gruenbacher2020-02-061-30/+21
| | | | | | | | | | | | In gfs2_file_write_iter, for direct writes, the error checking in the buffered write fallback case is incomplete. This can cause inode write errors to go undetected. Fix and clean up gfs2_file_write_iter along the way. Based on a proposed fix by Christoph Hellwig <hch@lst.de>. Fixes: 967bcc91b044 ("gfs2: iomap direct I/O support") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: move setting current->backing_dev_infoChristoph Hellwig2020-02-061-11/+10
| | | | | | | | | | Set current->backing_dev_info just around the buffered write calls to prepare for the next fix. Fixes: 967bcc91b044 ("gfs2: iomap direct I/O support") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
* gfs2: fix gfs2_find_jhead that returns uninitialized jhead with seq 0Abhi Das2020-02-061-1/+1
| | | | | | | | | | | | | | | When the first log header in a journal happens to have a sequence number of 0, a bug in gfs2_find_jhead() causes it to prematurely exit, and return an uninitialized jhead with seq 0. This can cause failures in the caller. For instance, a mount fails in one test case. The correct behavior is for it to continue searching through the journal to find the correct journal head with the highest sequence number. Fixes: f4686c26ecc3 ("gfs2: read journal in large chunks") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Abhi Das <adas@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
* Merge tag 'gfs2-for-5.6' of ↵Linus Torvalds2020-01-3112-70/+73
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 updates from Andreas Gruenbacher: - Fix some corner cases on filesystems with a block size < page size. - Fix a corner case that could expose incorrect access times over nfs. - Revert an otherwise sensible revoke accounting cleanup that causes assertion failures. The revoke accounting is whacky and needs to be fixed properly before we can add back this cleanup. - Various other minor cleanups. In addition, please expect to see another pull request from Bob Peterson about his gfs2 recovery patch queue shortly. * tag 'gfs2-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: Revert "gfs2: eliminate tr_num_revoke_rm" gfs2: remove unused LBIT macros fs/gfs2: remove unused IS_DINODE and IS_LEAF macros gfs2: Remove GFS2_MIN_LVB_SIZE define gfs2: Fix incorrect variable name gfs2: Avoid access time thrashing in gfs2_inode_lookup gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepage gfs2: eliminate ssize parameter from gfs2_struct2blk gfs2: Another gfs2_find_jhead fix
| * Revert "gfs2: eliminate tr_num_revoke_rm"Bob Peterson2020-01-283-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit e955537e3262de8e56f070b13817f525f472fa00. Before patch e955537e32, tr_num_revoke tracked the number of revokes added to the transaction, and tr_num_revoke_rm tracked how many revokes were removed. But since revokes are queued off the sdp (superblock) pointer, some transactions could remove more revokes than they added. (e.g. revokes added by a different process). Commit e955537e32 eliminated transaction variable tr_num_revoke_rm, but in order to do so, it changed the accounting to always use tr_num_revoke for its math. Since you can remove more revokes than you add, tr_num_revoke could now become a negative value. This negative value broke the assert in function gfs2_trans_end: if (gfs2_assert_withdraw(sdp, (nbuf <=3D tr->tr_blocks) && (tr->tr_num_revoke <=3D tr->tr_revokes))) One way to fix this is to simply remove the tr_num_revoke clause from the assert and allow the value to become negative. Andreas didn't like that idea, so instead, we decided to revert e955537e32. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * gfs2: remove unused LBIT macrosAlex Shi2020-01-211-10/+0
| | | | | | | | | | | | | | | | Since commit 223b2b889f37 ("GFS2: Fix alignment issue and tidy gfs2_bitfit"), these 3 macros aren't used anymore, so remove them. Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * fs/gfs2: remove unused IS_DINODE and IS_LEAF macrosAlex Shi2020-01-211-3/+0
| | | | | | | | | | | | | | | | Since commit 1579343a73e3 ("GFS2: Remove dirent_first() function"), these macros aren't used any more, so remove them. Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * gfs2: Remove GFS2_MIN_LVB_SIZE defineAndreas Gruenbacher2020-01-202-3/+1
| | | | | | | | | | | | | | | | The dlm lockspace is set up to have lock value blocks of GDLM_LVB_SIZE bytes, and dlm is the only lock manager we support, so there is no point in claiming that the lock value block could have any other size. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * gfs2: Fix incorrect variable nameAndreas Gruenbacher2020-01-202-6/+6
| | | | | | | | | | | | Rename sd_log_commited_revoke to sd_log_committed_revoke. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * gfs2: Avoid access time thrashing in gfs2_inode_lookupAndreas Gruenbacher2020-01-151-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | In gfs2_inode_lookup, we initialize inode->i_atime to the lowest possibly value after gfs2_inode_refresh may already have been called. This should be the other way around, but we didn't notice because usually the inode type is known from the directory entry and so gfs2_inode_lookup won't call gfs2_inode_refresh. In addition, only initialize ip->i_no_formal_ino from no_formal_ino when actually needed. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepageBob Peterson2020-01-081-3/+1
| | | | | | | | | | | | | | | | This patch simply removes variable ret, which is used to store the return code of its call to __gfs2_jdata_writepage, in favor of just returning the result directly. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
| * gfs2: eliminate ssize parameter from gfs2_struct2blkBob Peterson2020-01-077-14/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Every caller of function gfs2_struct2blk specified sizeof(u64). This patch eliminates the unnecessary parameter and replaces the size calculation with a new superblock variable that is computed to be the maximum number of block pointers we can fit inside a log descriptor, as is done for pointers per dinode and indirect block. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andrew Price <anprice@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * gfs2: Another gfs2_find_jhead fixAndreas Gruenbacher2020-01-071-24/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On filesystems with a block size smaller than the page size, gfs2_find_jhead can split a page across two bios (for example, when blocks are not allocated consecutively). When that happens, the first bio that completes will unlock the page in its bi_end_io handler even though the page hasn't been read completely yet. Fix that by using a chained bio for the rest of the page. While at it, clean up the sector calculation logic in gfs2_log_alloc_bio. In gfs2_find_jhead, simplify the disk block and offset calculation logic and fix a variable name. Fixes: f4686c26ecc3 ("gfs2: read journal in large chunks") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * Merge branch 'for-linus' from git://git.kernel.dk/linux-blockAndreas Gruenbacher2019-12-1011-33/+72
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* | \ Merge tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2020-01-312-13/+33
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull iomap fix from Darrick Wong: "A single patch fixing an off-by-one error when we're checking to see how far we're gotten into an EOF page" * tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: fs: Fix page_mkwrite off-by-one errors
| * | | fs: Fix page_mkwrite off-by-one errorsAndreas Gruenbacher2020-01-062-13/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The check in block_page_mkwrite that is meant to determine whether an offset is within the inode size is off by one. This bug has been copied into iomap_page_mkwrite and several filesystems (ubifs, ext4, f2fs, ceph). Fix that by introducing a new page_mkwrite_check_truncate helper that checks for truncate and computes the bytes in the page up to EOF. Use the helper in iomap. NOTE from Darrick: The original patch fixed a number of filesystems, but then there were merge conflicts with the f2fs for-next tree; a subsequent re-submission of the patch had different btrfs changes with no explanation; and Christoph complained that each per-fs fix should be a separate patch. In my view that's too much risk to take on, so I decided to drop all the hunks except for iomap, since I've actually QA'd XFS. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: drop everything but the iomap parts] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
* | | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2020-01-31136-1293/+2724
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull updates from Andrew Morton: "Most of -mm and quite a number of other subsystems: hotfixes, scripts, ocfs2, misc, lib, binfmt, init, reiserfs, exec, dma-mapping, kcov. MM is fairly quiet this time. Holidays, I assume" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) kcov: ignore fault-inject and stacktrace include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_atomic_wc() execve: warn if process starts with executable stack reiserfs: prevent NULL pointer dereference in reiserfs_insert_item() init/main.c: fix misleading "This architecture does not have kernel memory protection" message init/main.c: fix quoted value handling in unknown_bootoption init/main.c: remove unnecessary repair_env_string in do_initcall_level init/main.c: log arguments and environment passed to init fs/binfmt_elf.c: coredump: allow process with empty address space to coredump fs/binfmt_elf.c: coredump: delete duplicated overflow check fs/binfmt_elf.c: coredump: allocate core ELF header on stack fs/binfmt_elf.c: make BAD_ADDR() unlikely fs/binfmt_elf.c: better codegen around current->mm fs/binfmt_elf.c: don't copy ELF header around fs/binfmt_elf.c: fix ->start_code calculation fs/binfmt_elf.c: smaller code generation around auxv vector fill lib/find_bit.c: uninline helper _find_next_bit() lib/find_bit.c: join _find_next_bit{_le} uapi: rename ext2_swab() to swab() and share globally in swab.h lib/scatterlist.c: adjust indentation in __sg_alloc_table ...
| * | | | kcov: ignore fault-inject and stacktraceDmitry Vyukov2020-01-313-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't instrument 3 more files that contain debugging facilities and produce large amounts of uninteresting coverage for every syscall. The following snippets are sprinkled all over the place in kcov traces in a debugging kernel. We already try to disable instrumentation of stack unwinding code and of most debug facilities. I guess we did not use fault-inject.c at the time, and stacktrace.c was somehow missed (or something has changed in kernel/configs). This change both speeds up kcov (kernel doesn't need to store these PCs, user-space doesn't need to process them) and frees trace buffer capacity for more useful coverage. should_fail lib/fault-inject.c:149 fail_dump lib/fault-inject.c:45 stack_trace_save kernel/stacktrace.c:124 stack_trace_consume_entry kernel/stacktrace.c:86 stack_trace_consume_entry kernel/stacktrace.c:89 ... a hundred frames skipped ... stack_trace_consume_entry kernel/stacktrace.c:93 stack_trace_consume_entry kernel/stacktrace.c:86 Link: http://lkml.kernel.org/r/20200116111449.217744-1-dvyukov@gmail.com Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in ↵Andy Shevchenko2020-01-311-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | io_mapping_map_atomic_wc() Use PHYS_PFN() macro in io_mapping_map_atomic_wc() instead of open coded variant. Link: http://lkml.kernel.org/r/20191209165624.56351-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | execve: warn if process starts with executable stackAlexey Dobriyan2020-01-311-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There were few episodes of silent downgrade to an executable stack over years: 1) linking innocent looking assembly file will silently add executable stack if proper linker options is not given as well: $ cat f.S .intel_syntax noprefix .text .globl f f: ret $ cat main.c void f(void); int main(void) { f(); return 0; } $ gcc main.c f.S $ readelf -l ./a.out GNU_STACK 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 RWE 0x10 ^^^ 2) converting C99 nested function into a closure https://nullprogram.com/blog/2019/11/15/ void intsort2(int *base, size_t nmemb, _Bool invert) { int cmp(const void *a, const void *b) { int r = *(int *)a - *(int *)b; return invert ? -r : r; } qsort(base, nmemb, sizeof(*base), cmp); } will silently require stack trampolines while non-closure version will not. Without doubt this behaviour is documented somewhere, add a warning so that developers and users can at least notice. After so many years of x86_64 having proper executable stack support it should not cause too many problems. Link: http://lkml.kernel.org/r/20191208171918.GC19716@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Will Deacon <will@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | reiserfs: prevent NULL pointer dereference in reiserfs_insert_item()Yunfeng Ye2020-01-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The variable inode may be NULL in reiserfs_insert_item(), but there is no check before accessing the member of inode. Fix this by adding NULL pointer check before calling reiserfs_debug(). Link: http://lkml.kernel.org/r/79c5135d-ff25-1cc9-4e99-9f572b88cc00@huawei.com Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com> Cc: zhengbin <zhengbin13@huawei.com> Cc: Hu Shiyuan <hushiyuan@huawei.com> Cc: Feilong Lin <linfeilong@huawei.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | init/main.c: fix misleading "This architecture does not have kernel memory ↵Christophe Leroy2020-01-311-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | protection" message This message leads to thinking that memory protection is not implemented for the said architecture, whereas absence of CONFIG_STRICT_KERNEL_RWX only means that memory protection has not been selected at compile time. Don't print this message when CONFIG_ARCH_HAS_STRICT_KERNEL_RWX is selected by the architecture. Instead, print "Kernel memory protection not selected by kernel config." Link: http://lkml.kernel.org/r/62477e446d9685459d4f27d193af6ff1bd69d55f.1578557581.git.christophe.leroy@c-s.fr Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Acked-by: Kees Cook <keescook@chromium.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | init/main.c: fix quoted value handling in unknown_bootoptionArvind Sankar2020-01-311-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "init/main.c: minor cleanup/bugfix of envvar handling", v2. unknown_bootoption passes unrecognized command line arguments to init as either environment variables or arguments. Some of the logic in the function is broken for quoted command line arguments. When an argument of the form param="value" is processed by parse_args and passed to unknown_bootoption, the command line has param\0"value\0 with val pointing to the beginning of value. The helper function repair_env_string is then used to restore the '=' character that was removed by parse_args, and strip the quotes off fully. This results in param=value\0\0 and val ends up pointing to the 'a' instead of the 'v' in value. This bug was introduced when repair_env_string was refactored into a separate function, and the decrement of val in repair_env_string became dead code. This causes two problems in unknown_bootoption in the two places where the val pointer is used as a substitute for the length of param: 1. An argument of the form param=".value" is misinterpreted as a potential module parameter, with the result that it will not be placed in init's environment. 2. An argument of the form param="value" is checked to see if param is an existing environment variable that should be overwritten, but the comparison is off-by-one and compares 'param=v' instead of 'param=' against the existing environment. So passing, for example, TERM="vt100" on the command line results in init being passed both TERM=linux and TERM=vt100 in its environment. Patch 1 adds logging for the arguments and environment passed to init and is independent of the rest: it can be dropped if this is unnecessarily verbose. Patch 2 removes repair_env_string from initcall parameter parsing in do_initcall_level, as that uses a separate copy of the command line now and the repairing is no longer necessary. Patch 3 fixes the bug in unknown_bootoption by recording the length of param explicitly instead of implying it from val-param. This patch (of 3): Commit a99cd1125189 ("init: fix bug where environment vars can't be passed via boot args") introduced two minor bugs in unknown_bootoption by factoring out the quoted value handling into a separate function. When value is quoted, repair_env_string will move the value up 1 byte to strip the quotes, so val in unknown_bootoption no longer points to the actual location of the value. The result is that an argument of the form param=".value" is mistakenly treated as a potential module parameter and is not placed in init's environment, and an argument of the form param="value" can result in a duplicate environment variable: eg TERM="vt100" on the command line will result in both TERM=linux and TERM=vt100 being placed into init's environment. Fix this by recording the length of the param before calling repair_env_string instead of relying on val. Link: http://lkml.kernel.org/r/20191212180023.24339-4-nivedita@alum.mit.edu Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Krzysztof Mazur <krzysiek@podlesie.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | init/main.c: remove unnecessary repair_env_string in do_initcall_levelArvind Sankar2020-01-311-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 08746a65c296 ("init: fix in-place parameter modification regression"), parse_args in do_initcall_level is called on a copy of saved_command_line. It is unnecessary to call repair_env_string during this parsing, as this copy is not used for anything later. Remove the now unnecessary arguments from repair_env_string as well. Link: http://lkml.kernel.org/r/20191212180023.24339-3-nivedita@alum.mit.edu Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Cc: Krzysztof Mazur <krzysiek@podlesie.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | init/main.c: log arguments and environment passed to initArvind Sankar2020-01-311-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extend logging in `run_init_process` to also show the arguments and environment that we are passing to init. Link: http://lkml.kernel.org/r/20191212180023.24339-2-nivedita@alum.mit.edu Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Krzysztof Mazur <krzysiek@podlesie.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: coredump: allow process with empty address space to coredumpAlexey Dobriyan2020-01-311-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unmapping whole address space at once with munmap(0, (1ULL<<47) - 4096) or equivalent will create empty coredump. It is silly way to exit, however registers content may still be useful. The right to coredump is fundamental right of a process! Link: http://lkml.kernel.org/r/20191222150137.GA1277@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: coredump: delete duplicated overflow checkAlexey Dobriyan2020-01-311-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | array_size() macro will do overflow check anyway. Link: http://lkml.kernel.org/r/20191222144009.GB24341@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: coredump: allocate core ELF header on stackAlexey Dobriyan2020-01-311-11/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Comment says ELF header is "too large to be on stack". 64 bytes on 64-bit is not large by any means. Link: http://lkml.kernel.org/r/20191222143850.GA24341@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: make BAD_ADDR() unlikelyAlexey Dobriyan2020-01-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If some mapping goes past TASK_SIZE it will be rejected by kernel which means no such userspace binaries exist. Mark every such check as unlikely. Link: http://lkml.kernel.org/r/20191215124355.GA21124@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: better codegen around current->mmAlexey Dobriyan2020-01-311-24/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "current->mm" pointer is stable in general except few cases one of which execve(2). Compiler can't treat is as stable but it _is_ stable most of the time. During ELF loading process ->mm becomes stable right after flush_old_exec(). Help compiler by caching current->mm, otherwise it continues to refetch it. add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-141 (-141) Function old new delta elf_core_dump 5062 5039 -23 load_elf_binary 5426 5308 -118 Note: other cases are left as is because it is either pessimisation or no change in binary size. Link: http://lkml.kernel.org/r/20191215124755.GB21124@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: don't copy ELF header aroundAlexey Dobriyan2020-01-311-28/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ELF header is read into bprm->buf[] by generic execve code. Save a memcpy and allocate just one header for the interpreter instead of two headers (64 bytes instead of 128 on 64-bit). Link: http://lkml.kernel.org/r/20191208171242.GA19716@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: fix ->start_code calculationAlexey Dobriyan2020-01-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only executable segments should be accounted to ->start_code just like they do to ->end_code (correctly). Link: http://lkml.kernel.org/r/20191208171410.GB19716@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | fs/binfmt_elf.c: smaller code generation around auxv vector fillAlexey Dobriyan2020-01-311-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Filling auxv vector as array with index (auxv[i++] = ...) generates terrible code. "saved_auxv" should be reworked because it is the worst member of mm_struct by size/usefullness ratio but do it later. Meanwhile help gcc a little with *auxv++ idiom. Space savings on x86_64: add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-127 (-127) Function old new delta load_elf_binary 5470 5343 -127 Link: http://lkml.kernel.org/r/20191208172301.GD19716@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | lib/find_bit.c: uninline helper _find_next_bit()Yury Norov2020-01-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It saves 25% of .text for arm64, and more for BE architectures. Before: $ size lib/find_bit.o text data bss dec hex filename 1012 56 0 1068 42c lib/find_bit.o After: $ size lib/find_bit.o text data bss dec hex filename 776 56 0 832 340 lib/find_bit.o Link: http://lkml.kernel.org/r/20200103202846.21616-3-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Allison Randal <allison@lohutok.net> Cc: William Breathitt Gray <vilhelm.gray@gmail.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | lib/find_bit.c: join _find_next_bit{_le}Yury Norov2020-01-311-45/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | _find_next_bit and _find_next_bit_le are very similar functions. It's possible to join them by adding 1 parameter and a couple of simple checks. It's simplify maintenance and make possible to shrink the size of .text by un-inlining the unified function (in the following patch). Link: http://lkml.kernel.org/r/20200103202846.21616-2-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Cc: Allison Randal <allison@lohutok.net> Cc: Joe Perches <joe@perches.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | uapi: rename ext2_swab() to swab() and share globally in swab.hYury Norov2020-01-313-14/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ext2_swab() is defined locally in lib/find_bit.c However it is not specific to ext2, neither to bitmaps. There are many potential users of it, so rename it to just swab() and move to include/uapi/linux/swab.h ABI guarantees that size of unsigned long corresponds to BITS_PER_LONG, therefore drop unneeded cast. Link: http://lkml.kernel.org/r/20200103202846.21616-1-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Cc: Allison Randal <allison@lohutok.net> Cc: Joe Perches <joe@perches.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | lib/scatterlist.c: adjust indentation in __sg_alloc_tableNathan Chancellor2020-01-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clang warns: ../lib/scatterlist.c:314:5: warning: misleading indentation; statement is not part of the previous 'if' [-Wmisleading-indentation] return -ENOMEM; ^ ../lib/scatterlist.c:311:4: note: previous statement is here if (prv) ^ 1 warning generated. This warning occurs because there is a space before the tab on this line. Remove it so that the indentation is consistent with the Linux kernel coding style and clang no longer warns. Link: http://lkml.kernel.org/r/20191218033606.11942-1-natechancellor@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/830 Fixes: edce6820a9fd ("scatterlist: prevent invalid free when alloc fails") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | btrfs: use larger zlib buffer for s390 hardware compressionMikhail Zaslonko2020-01-312-36/+101
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to benefit from s390 zlib hardware compression support, increase the btrfs zlib workspace buffer size from 1 to 4 pages (if s390 zlib hardware support is enabled on the machine). This brings up to 60% better performance in hardware on s390 compared to the PAGE_SIZE buffer and much more compared to the software zlib processing in btrfs. In case of memory pressure, fall back to a single page buffer during workspace allocation. The data compressed with larger input buffers will still conform to zlib standard and thus can be decompressed also on a systems that uses only PAGE_SIZE buffer for btrfs zlib. Link: http://lkml.kernel.org/r/20200108105103.29028-1-zaslonko@linux.ibm.com Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reviewed-by: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: David Sterba <dsterba@suse.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Eduard Shishkin <edward6@linux.ibm.com> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>