1. 30 Sep, 2013 22 commits
    • Wanpeng Li's avatar
      mm/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood · 20cb6cab
      Wanpeng Li authored
      madvise_hwpoison won't check if the page is small page or huge page and
      traverses in small page granularity against the range unconditionally,
      which result in a printk flood "MCE xxx: already hardware poisoned" if
      the page is a huge page.
      
      This patch fixes it by using compound_order(compound_head(page)) for
      huge page iterator.
      
      Testcase:
      
      #define _GNU_SOURCE
      #include <stdlib.h>
      #include <stdio.h>
      #include <sys/mman.h>
      #include <unistd.h>
      #include <fcntl.h>
      #include <sys/types.h>
      #include <errno.h>
      
      #define PAGES_TO_TEST 3
      #define PAGE_SIZE	4096 * 512
      
      int main(void)
      {
      	char *mem;
      	int i;
      
      	mem = mmap(NULL, PAGES_TO_TEST * PAGE_SIZE,
      			PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, 0, 0);
      
      	if (madvise(mem, PAGES_TO_TEST * PAGE_SIZE, MADV_HWPOISON) == -1)
      		return -1;
      
      	munmap(mem, PAGES_TO_TEST * PAGE_SIZE);
      
      	return 0;
      }
      Signed-off-by: default avatarWanpeng Li <liwanp@linux.vnet.ibm.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Acked-by: default avatarAndi Kleen <ak@linux.intel.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      20cb6cab
    • Paul Gortmaker's avatar
      block: change config option name for cmdline partition parsing · 080506ad
      Paul Gortmaker authored
      Recently commit bab55417 ("block: support embedded device command
      line partition") introduced CONFIG_CMDLINE_PARSER.  However, that name
      is too generic and sounds like it enables/disables generic kernel boot
      arg processing, when it really is block specific.
      
      Before this option becomes a part of a full/final release, add the BLK_
      prefix to it so that it is clear in absence of any other context that it
      is block specific.
      
      In addition, fix up the following less critical items:
       - help text was not really at all helpful.
       - index file for Documentation was not updated
       - add the new arg to Documentation/kernel-parameters.txt
       - clarify wording in source comments
      Signed-off-by: default avatarPaul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Cai Zhiyong <caizhiyong@huawei.com>
      Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      080506ad
    • Vlastimil Babka's avatar
      mm/mlock.c: prevent walking off the end of a pagetable in no-pmd configuration · eadb41ae
      Vlastimil Babka authored
      The function __munlock_pagevec_fill() introduced in commit 7a8010cd
      ("mm: munlock: manual pte walk in fast path instead of
      follow_page_mask()") uses pmd_addr_end() for restricting its operation
      within current page table.
      
      This is insufficient on architectures/configurations where pmd is folded
      and pmd_addr_end() just returns the end of the full range to be walked.
      In this case, it allows pte++ to walk off the end of a page table
      resulting in unpredictable behaviour.
      
      This patch fixes the function by using pgd_addr_end() and pud_addr_end()
      before pmd_addr_end(), which will yield correct page table boundary on
      all configurations.  This is similar to what existing page walkers do
      when walking each level of the page table.
      
      Additionaly, the patch clarifies a comment for get_locked_pte() call in the
      function.
      Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Reported-by: default avatarFengguang Wu <fengguang.wu@intel.com>
      Reviewed-by: default avatarBob Liu <bob.liu@oracle.com>
      Cc: Jörn Engel <joern@logfs.org>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Michel Lespinasse <walken@google.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      eadb41ae
    • Rafael Aquini's avatar
      mm: avoid reinserting isolated balloon pages into LRU lists · 117aad1e
      Rafael Aquini authored
      Isolated balloon pages can wrongly end up in LRU lists when
      migrate_pages() finishes its round without draining all the isolated
      page list.
      
      The same issue can happen when reclaim_clean_pages_from_list() tries to
      reclaim pages from an isolated page list, before migration, in the CMA
      path.  Such balloon page leak opens a race window against LRU lists
      shrinkers that leads us to the following kernel panic:
      
        BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
        IP: [<ffffffff810c2625>] shrink_page_list+0x24e/0x897
        PGD 3cda2067 PUD 3d713067 PMD 0
        Oops: 0000 [#1] SMP
        CPU: 0 PID: 340 Comm: kswapd0 Not tainted 3.12.0-rc1-22626-g4367597 #87
        Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
        RIP: shrink_page_list+0x24e/0x897
        RSP: 0000:ffff88003da499b8  EFLAGS: 00010286
        RAX: 0000000000000000 RBX: ffff88003e82bd60 RCX: 00000000000657d5
        RDX: 0000000000000000 RSI: 000000000000031f RDI: ffff88003e82bd40
        RBP: ffff88003da49ab0 R08: 0000000000000001 R09: 0000000081121a45
        R10: ffffffff81121a45 R11: ffff88003c4a9a28 R12: ffff88003e82bd40
        R13: ffff88003da0e800 R14: 0000000000000001 R15: ffff88003da49d58
        FS:  0000000000000000(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
        CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
        CR2: 00000000067d9000 CR3: 000000003ace5000 CR4: 00000000000407b0
        Call Trace:
          shrink_inactive_list+0x240/0x3de
          shrink_lruvec+0x3e0/0x566
          __shrink_zone+0x94/0x178
          shrink_zone+0x3a/0x82
          balance_pgdat+0x32a/0x4c2
          kswapd+0x2f0/0x372
          kthread+0xa2/0xaa
          ret_from_fork+0x7c/0xb0
        Code: 80 7d 8f 01 48 83 95 68 ff ff ff 00 4c 89 e7 e8 5a 7b 00 00 48 85 c0 49 89 c5 75 08 80 7d 8f 00 74 3e eb 31 48 8b 80 18 01 00 00 <48> 8b 74 0d 48 8b 78 30 be 02 00 00 00 ff d2 eb
        RIP  [<ffffffff810c2625>] shrink_page_list+0x24e/0x897
         RSP <ffff88003da499b8>
        CR2: 0000000000000028
        ---[ end trace 703d2451af6ffbfd ]---
        Kernel panic - not syncing: Fatal exception
      
      This patch fixes the issue, by assuring the proper tests are made at
      putback_movable_pages() & reclaim_clean_pages_from_list() to avoid
      isolated balloon pages being wrongly reinserted in LRU lists.
      
      [akpm@linux-foundation.org: clarify awkward comment text]
      Signed-off-by: default avatarRafael Aquini <aquini@redhat.com>
      Reported-by: default avatarLuiz Capitulino <lcapitulino@redhat.com>
      Tested-by: default avatarLuiz Capitulino <lcapitulino@redhat.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      117aad1e
    • Felipe Pena's avatar
      arch/parisc/mm/fault.c: fix uninitialized variable usage · 0772dac1
      Felipe Pena authored
      The FAULT_FLAG_WRITE flag has been set based on uninitialized variable.
      
      Fixes a regression added by commit 759496ba ("arch: mm: pass
      userspace fault flag to generic fault handler")
      Signed-off-by: default avatarFelipe Pena <felipensp@gmail.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Helge Deller <deller@gmx.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      0772dac1
    • Andrew Morton's avatar
      include/asm-generic/vtime.h: avoid zero-length file · 2a156a6b
      Andrew Morton authored
      patch(1) can't handle zero-length files - it appears to simply not create
      the file, so my powerpc build fails.
      
      Put something in here to make life easier.
      
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2a156a6b
    • Vyacheslav Dubeyko's avatar
      nilfs2: fix issue with race condition of competition between segments for dirty blocks · 7f42ec39
      Vyacheslav Dubeyko authored
      Many NILFS2 users were reported about strange file system corruption
      (for example):
      
         NILFS: bad btree node (blocknr=185027): level = 0, flags = 0x0, nchildren = 768
         NILFS error (device sda4): nilfs_bmap_last_key: broken bmap (inode number=11540)
      
      But such error messages are consequence of file system's issue that takes
      place more earlier.  Fortunately, Jerome Poulin <jeromepoulin@gmail.com>
      and Anton Eliasson <devel@antoneliasson.se> were reported about another
      issue not so recently.  These reports describe the issue with segctor
      thread's crash:
      
        BUG: unable to handle kernel paging request at 0000000000004c83
        IP: nilfs_end_page_io+0x12/0xd0 [nilfs2]
      
        Call Trace:
         nilfs_segctor_do_construct+0xf25/0x1b20 [nilfs2]
         nilfs_segctor_construct+0x17b/0x290 [nilfs2]
         nilfs_segctor_thread+0x122/0x3b0 [nilfs2]
         kthread+0xc0/0xd0
         ret_from_fork+0x7c/0xb0
      
      These two issues have one reason.  This reason can raise third issue
      too.  Third issue results in hanging of segctor thread with eating of
      100% CPU.
      
      REPRODUCING PATH:
      
      One of the possible way or the issue reproducing was described by
      Jermoe me Poulin <jeromepoulin@gmail.com>:
      
      1. init S to get to single user mode.
      2. sysrq+E to make sure only my shell is running
      3. start network-manager to get my wifi connection up
      4. login as root and launch "screen"
      5. cd /boot/log/nilfs which is a ext3 mount point and can log when NILFS dies.
      6. lscp | xz -9e > lscp.txt.xz
      7. mount my snapshot using mount -o cp=3360839,ro /dev/vgUbuntu/root /mnt/nilfs
      8. start a screen to dump /proc/kmsg to text file since rsyslog is killed
      9. start a screen and launch strace -f -o find-cat.log -t find
      /mnt/nilfs -type f -exec cat {} > /dev/null \;
      10. start a screen and launch strace -f -o apt-get.log -t apt-get update
      11. launch the last command again as it did not crash the first time
      12. apt-get crashes
      13. ps aux > ps-aux-crashed.log
      13. sysrq+W
      14. sysrq+E  wait for everything to terminate
      15. sysrq+SUSB
      
      Simplified way of the issue reproducing is starting kernel compilation
      task and "apt-get update" in parallel.
      
      REPRODUCIBILITY:
      
      The issue is reproduced not stable [60% - 80%].  It is very important to
      have proper environment for the issue reproducing.  The critical
      conditions for successful reproducing:
      
      (1) It should have big modified file by mmap() way.
      
      (2) This file should have the count of dirty blocks are greater that
          several segments in size (for example, two or three) from time to time
          during processing.
      
      (3) It should be intensive background activity of files modification
          in another thread.
      
      INVESTIGATION:
      
      First of all, it is possible to see that the reason of crash is not valid
      page address:
      
        NILFS [nilfs_segctor_complete_write]:2100 bh->b_count 0, bh->b_blocknr 13895680, bh->b_size 13897727, bh->b_page 0000000000001a82
        NILFS [nilfs_segctor_complete_write]:2101 segbuf->sb_segnum 6783
      
      Moreover, value of b_page (0x1a82) is 6786.  This value looks like segment
      number.  And b_blocknr with b_size values look like block numbers.  So,
      buffer_head's pointer points on not proper address value.
      
      Detailed investigation of the issue is discovered such picture:
      
        [-----------------------------SEGMENT 6783-------------------------------]
        NILFS [nilfs_segctor_do_construct]:2310 nilfs_segctor_begin_construction
        NILFS [nilfs_segctor_do_construct]:2321 nilfs_segctor_collect
        NILFS [nilfs_segctor_do_construct]:2336 nilfs_segctor_assign
        NILFS [nilfs_segctor_do_construct]:2367 nilfs_segctor_update_segusage
        NILFS [nilfs_segctor_do_construct]:2371 nilfs_segctor_prepare_write
        NILFS [nilfs_segctor_do_construct]:2376 nilfs_add_checksums_on_logs
        NILFS [nilfs_segctor_do_construct]:2381 nilfs_segctor_write
        NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111149024, segbuf->sb_segnum 6783
      
        [-----------------------------SEGMENT 6784-------------------------------]
        NILFS [nilfs_segctor_do_construct]:2310 nilfs_segctor_begin_construction
        NILFS [nilfs_segctor_do_construct]:2321 nilfs_segctor_collect
        NILFS [nilfs_lookup_dirty_data_buffers]:782 bh->b_count 1, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
        NILFS [nilfs_lookup_dirty_data_buffers]:783 bh->b_assoc_buffers.next ffff8802174a6798, bh->b_assoc_buffers.prev ffff880221cffee8
        NILFS [nilfs_segctor_do_construct]:2336 nilfs_segctor_assign
        NILFS [nilfs_segctor_do_construct]:2367 nilfs_segctor_update_segusage
        NILFS [nilfs_segctor_do_construct]:2371 nilfs_segctor_prepare_write
        NILFS [nilfs_segctor_do_construct]:2376 nilfs_add_checksums_on_logs
        NILFS [nilfs_segctor_do_construct]:2381 nilfs_segctor_write
        NILFS [nilfs_segbuf_submit_bh]:575 bh->b_count 1, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
        NILFS [nilfs_segbuf_submit_bh]:576 segbuf->sb_segnum 6784
        NILFS [nilfs_segbuf_submit_bh]:577 bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880218bcdf50
        NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111150080, segbuf->sb_segnum 6784, segbuf->sb_nbio 0
        [----------] ditto
        NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111164416, segbuf->sb_segnum 6784, segbuf->sb_nbio 15
      
        [-----------------------------SEGMENT 6785-------------------------------]
        NILFS [nilfs_segctor_do_construct]:2310 nilfs_segctor_begin_construction
        NILFS [nilfs_segctor_do_construct]:2321 nilfs_segctor_collect
        NILFS [nilfs_lookup_dirty_data_buffers]:782 bh->b_count 2, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
        NILFS [nilfs_lookup_dirty_data_buffers]:783 bh->b_assoc_buffers.next ffff880219277e80, bh->b_assoc_buffers.prev ffff880221cffc88
        NILFS [nilfs_segctor_do_construct]:2367 nilfs_segctor_update_segusage
        NILFS [nilfs_segctor_do_construct]:2371 nilfs_segctor_prepare_write
        NILFS [nilfs_segctor_do_construct]:2376 nilfs_add_checksums_on_logs
        NILFS [nilfs_segctor_do_construct]:2381 nilfs_segctor_write
        NILFS [nilfs_segbuf_submit_bh]:575 bh->b_count 2, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
        NILFS [nilfs_segbuf_submit_bh]:576 segbuf->sb_segnum 6785
        NILFS [nilfs_segbuf_submit_bh]:577 bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880222cc7ee8
        NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111165440, segbuf->sb_segnum 6785, segbuf->sb_nbio 0
        [----------] ditto
        NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111177728, segbuf->sb_segnum 6785, segbuf->sb_nbio 12
      
        NILFS [nilfs_segctor_do_construct]:2399 nilfs_segctor_wait
        NILFS [nilfs_segbuf_wait]:676 segbuf->sb_segnum 6783
        NILFS [nilfs_segbuf_wait]:676 segbuf->sb_segnum 6784
        NILFS [nilfs_segbuf_wait]:676 segbuf->sb_segnum 6785
      
        NILFS [nilfs_segctor_complete_write]:2100 bh->b_count 0, bh->b_blocknr 13895680, bh->b_size 13897727, bh->b_page 0000000000001a82
      
        BUG: unable to handle kernel paging request at 0000000000001a82
        IP: [<ffffffffa024d0f2>] nilfs_end_page_io+0x12/0xd0 [nilfs2]
      
      Usually, for every segment we collect dirty files in list.  Then, dirty
      blocks are gathered for every dirty file, prepared for write and
      submitted by means of nilfs_segbuf_submit_bh() call.  Finally, it takes
      place complete write phase after calling nilfs_end_bio_write() on the
      block layer.  Buffers/pages are marked as not dirty on final phase and
      processed files removed from the list of dirty files.
      
      It is possible to see that we had three prepare_write and submit_bio
      phases before segbuf_wait and complete_write phase.  Moreover, segments
      compete between each other for dirty blocks because on every iteration
      of segments processing dirty buffer_heads are added in several lists of
      payload_buffers:
      
        [SEGMENT 6784]: bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880218bcdf50
        [SEGMENT 6785]: bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880222cc7ee8
      
      The next pointer is the same but prev pointer has changed.  It means
      that buffer_head has next pointer from one list but prev pointer from
      another.  Such modification can be made several times.  And, finally, it
      can be resulted in various issues: (1) segctor hanging, (2) segctor
      crashing, (3) file system metadata corruption.
      
      FIX:
      This patch adds:
      
      (1) setting of BH_Async_Write flag in nilfs_segctor_prepare_write()
          for every proccessed dirty block;
      
      (2) checking of BH_Async_Write flag in
          nilfs_lookup_dirty_data_buffers() and
          nilfs_lookup_dirty_node_buffers();
      
      (3) clearing of BH_Async_Write flag in nilfs_segctor_complete_write(),
          nilfs_abort_logs(), nilfs_forget_buffer(), nilfs_clear_dirty_page().
      Reported-by: default avatarJerome Poulin <jeromepoulin@gmail.com>
      Reported-by: default avatarAnton Eliasson <devel@antoneliasson.se>
      Cc: Paul Fertser <fercerpav@gmail.com>
      Cc: ARAI Shun-ichi <hermes@ceres.dti.ne.jp>
      Cc: Piotr Szymaniak <szarpaj@grubelek.pl>
      Cc: Juan Barry Manuel Canham <Linux@riotingpacifist.net>
      Cc: Zahid Chowdhury <zahid.chowdhury@starsolutions.com>
      Cc: Elmer Zhang <freeboy6716@gmail.com>
      Cc: Kenneth Langga <klangga@gmail.com>
      Signed-off-by: default avatarVyacheslav Dubeyko <slava@dubeyko.com>
      Acked-by: default avatarRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      7f42ec39
    • Weiping Pan's avatar
      Documentation/kernel-parameters.txt: replace kernelcore with Movable · 675217fd
      Weiping Pan authored
      Han Pingtian found a typo in Documentation/kernel-parameters.txt about
      "kernelcore=", that "kernelcore" should be replaced with "Movable" here.
      Signed-off-by: default avatarWeiping Pan <wpan@redhat.com>
      Acked-by: default avatarMel Gorman <mgorman@suse.de>
      Cc: Randy Dunlap <rdunlap@infradead.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      675217fd
    • Darrick J. Wong's avatar
      mm/bounce.c: fix a regression where MS_SNAP_STABLE (stable pages snapshotting) was ignored · 83b2944f
      Darrick J. Wong authored
      The "force" parameter in __blk_queue_bounce was being ignored, which
      means that stable page snapshots are not always happening (on ext3).
      This of course leads to DIF disks reporting checksum errors, so fix this
      regression.
      
      The regression was introduced in commit 6bc454d1 ("bounce: Refactor
      __blk_queue_bounce to not use bi_io_vec")
      Reported-by: default avatarMel Gorman <mgorman@suse.de>
      Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
      Cc: Kent Overstreet <koverstreet@google.com>
      Cc: <stable@vger.kernel.org>	[3.10+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      83b2944f
    • Tetsuo Handa's avatar
      kernel/kmod.c: check for NULL in call_usermodehelper_exec() · 4c1c7be9
      Tetsuo Handa authored
      If /proc/sys/kernel/core_pattern contains only "|", a NULL pointer
      dereference happens upon core dump because argv_split("") returns
      argv[0] == NULL.
      
      This bug was once fixed by commit 264b83c0 ("usermodehelper: check
      subprocess_info->path != NULL") but was by error reintroduced by commit
      7f57cfa4 ("usermodehelper: kill the sub_info->path[0] check").
      
      This bug seems to exist since 2.6.19 (the version which core dump to
      pipe was added).  Depending on kernel version and config, some side
      effect might happen immediately after this oops (e.g.  kernel panic with
      2.6.32-358.18.1.el6).
      Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Acked-by: default avatarOleg Nesterov <oleg@redhat.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4c1c7be9
    • Manfred Spraul's avatar
      ipc/sem.c: synchronize the proc interface · d8c63376
      Manfred Spraul authored
      The proc interface is not aware of sem_lock(), it instead calls
      ipc_lock_object() directly.  This means that simple semop() operations
      can run in parallel with the proc interface.  Right now, this is
      uncritical, because the implementation doesn't do anything that requires
      a proper synchronization.
      
      But it is dangerous and therefore should be fixed.
      Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Rik van Riel <riel@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d8c63376
    • Manfred Spraul's avatar
      ipc/sem.c: optimize sem_lock() · 6d07b68c
      Manfred Spraul authored
      Operations that need access to the whole array must guarantee that there
      are no simple operations ongoing.  Right now this is achieved by
      spin_unlock_wait(sem->lock) on all semaphores.
      
      If complex_count is nonzero, then this spin_unlock_wait() is not
      necessary, because it was already performed in the past by the thread
      that increased complex_count and even though sem_perm.lock was dropped
      inbetween, no simple operation could have started, because simple
      operations cannot start when complex_count is non-zero.
      Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Mike Galbraith <bitbucket@online.de>
      Cc: Rik van Riel <riel@redhat.com>
      Reviewed-by: default avatarDavidlohr Bueso <davidlohr@hp.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      6d07b68c
    • Manfred Spraul's avatar
      ipc/sem.c: fix race in sem_lock() · 5e9d5275
      Manfred Spraul authored
      The exclusion of complex operations in sem_lock() is insufficient: after
      acquiring the per-semaphore lock, a simple op must first check that
      sem_perm.lock is not locked and only after that test check
      complex_count.  The current code does it the other way around - and that
      creates a race.  Details are below.
      
      The patch is a complete rewrite of sem_lock(), based in part on the code
      from Mike Galbraith.  It removes all gotos and all loops and thus the
      risk of livelocks.
      
      I have tested the patch (together with the next one) on my i3 laptop and
      it didn't cause any problems.
      
      The bug is probably also present in 3.10 and 3.11, but for these kernels
      it might be simpler just to move the test of sma->complex_count after
      the spin_is_locked() test.
      
      Details of the bug:
      
      Assume:
       - sma->complex_count = 0.
       - Thread 1: semtimedop(complex op that must sleep)
       - Thread 2: semtimedop(simple op).
      
      Pseudo-Trace:
      
      Thread 1: sem_lock(): acquire sem_perm.lock
      Thread 1: sem_lock(): check for ongoing simple ops
      			Nothing ongoing, thread 2 is still before sem_lock().
      Thread 1: try_atomic_semop()
      	<<< preempted.
      
      Thread 2: sem_lock():
              static inline int sem_lock(struct sem_array *sma, struct sembuf *sops,
                                            int nsops)
              {
                      int locknum;
               again:
                      if (nsops == 1 && !sma->complex_count) {
                              struct sem *sem = sma->sem_base + sops->sem_num;
      
                              /* Lock just the semaphore we are interested in. */
                              spin_lock(&sem->lock);
      
                              /*
                               * If sma->complex_count was set while we were spinning,
                               * we may need to look at things we did not lock here.
                               */
                              if (unlikely(sma->complex_count)) {
                                      spin_unlock(&sem->lock);
                                      goto lock_array;
                              }
              <<<<<<<<<
      	<<< complex_count is still 0.
      	<<<
              <<< Here it is preempted
              <<<<<<<<<
      
      Thread 1: try_atomic_semop() returns, notices that it must sleep.
      Thread 1: increases sma->complex_count.
      Thread 1: drops sem_perm.lock
      Thread 2:
                      /*
                       * Another process is holding the global lock on the
                       * sem_array; we cannot enter our critical section,
                       * but have to wait for the global lock to be released.
                       */
                      if (unlikely(spin_is_locked(&sma->sem_perm.lock))) {
                              spin_unlock(&sem->lock);
                              spin_unlock_wait(&sma->sem_perm.lock);
                              goto again;
                      }
      	<<< sem_perm.lock already dropped, thus no "goto again;"
      
                      locknum = sops->sem_num;
      Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Mike Galbraith <bitbucket@online.de>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
      Cc: <stable@vger.kernel.org>	[3.10+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      5e9d5275
    • David Rientjes's avatar
      mm/compaction.c: periodically schedule when freeing pages · f6ea3adb
      David Rientjes authored
      We've been getting warnings about an excessive amount of time spent
      allocating pages for migration during memory compaction without
      scheduling.  isolate_freepages_block() already periodically checks for
      contended locks or the need to schedule, but isolate_freepages() never
      does.
      
      When a zone is massively long and no suitable targets can be found, this
      iteration can be quite expensive without ever doing cond_resched().
      
      Check periodically for the need to reschedule while the compaction free
      scanner iterates.
      Signed-off-by: default avatarDavid Rientjes <rientjes@google.com>
      Reviewed-by: default avatarRik van Riel <riel@redhat.com>
      Reviewed-by: default avatarWanpeng Li <liwanp@linux.vnet.ibm.com>
      Acked-by: default avatarMel Gorman <mgorman@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f6ea3adb
    • Dan Aloni's avatar
      fs/binfmt_elf.c: prevent a coredump with a large vm_map_count from Oopsing · 72023656
      Dan Aloni authored
      A high setting of max_map_count, and a process core-dumping with a large
      enough vm_map_count could result in an NT_FILE note not being written,
      and the kernel crashing immediately later because it has assumed
      otherwise.
      
      Reproduction of the oops-causing bug described here:
      
          https://lkml.org/lkml/2013/8/30/50
      
      Rge ussue originated in commit 2aa362c4 ("coredump: extend core dump
      note section to contain file names of mapped file") from Oct 4, 2012.
      
      This patch make that section optional in that case.  fill_files_note()
      should signify the error, and also let the info struct in
      elf_core_dump() be zero-initialized so that we can check for the
      optionally written note.
      
      [akpm@linux-foundation.org: avoid abusing E2BIG, remove a couple of not-really-needed local variables]
      [akpm@linux-foundation.org: fix sparse warning]
      Signed-off-by: default avatarDan Aloni <alonid@stratoscale.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Denys Vlasenko <vda.linux@googlemail.com>
      Reported-by: default avatarMartin MOKREJS <mmokrejs@gmail.com>
      Tested-by: default avatarMartin MOKREJS <mmokrejs@gmail.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      72023656
    • Joonyoung Shim's avatar
      revert "mm/memory-hotplug: fix lowmem count overflow when offline pages" · 7393dc45
      Joonyoung Shim authored
      This reverts commit cea27eb2 ("mm/memory-hotplug: fix lowmem count
      overflow when offline pages").
      
      The fixed bug by commit cea27eb2 was fixed to another way by commit
      3dcc0571 ("mm: correctly update zone->managed_pages").  That commit
      enhances memory_hotplug.c to adjust totalhigh_pages when hot-removing
      memory, for details please refer to:
      
        http://marc.info/?l=linux-mm&m=136957578620221&w=2
      
      As a result, commit cea27eb2 currently causes duplicated decreasing
      of totalhigh_pages, thus the revert.
      Signed-off-by: default avatarJoonyoung Shim <jy0922.shim@samsung.com>
      Reviewed-by: default avatarWanpeng Li <liwanp@linux.vnet.ibm.com>
      Cc: Jiang Liu <liuj97@gmail.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      7393dc45
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32 · 5c282e85
      Linus Torvalds authored
      Pull AVR32 fixes from Hans-Christian Egtvedt.
      
      Fix build warnings and use the Kbuild infrastructure for generic headers
      rather than doing it by hand.
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32:
        avr32: cast syscall_return to silence compiler warning
        avr32: fix clockevents kernel warning
        avr32: use Kbuild infrastructure to handle the asm-generic headers
      5c282e85
    • Linus Torvalds's avatar
      Merge tag 'for-linus-20130929' of git://github.com/sctscore/official-linux · 8945546d
      Linus Torvalds authored
      Pull S+core fixes from Lennox Wu:
       "These updates include updating information of maintainers, fix some
        trivial errors, and add a necessary function for supporting ipv6"
      
      * tag 'for-linus-20130929' of git://github.com/sctscore/official-linux:
        Score: Update the information of Score maintaners
        Score: Modify the Makefile of Score, remove -mlong-calls for compiling
        Score: Implement the function csum_ipv6_magic
        Score: The commit is for compiling successfully
      8945546d
    • Linus Torvalds's avatar
      Merge tag 'arc-fixes-for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc · 815a4bb1
      Linus Torvalds authored
      Pull ARC Fixes from Vineet Gupta:
       - Handle unaligned access in zero delay loops
       - spinlock livelock fix for SMP systemC model
       - fix 32bit overflow in access_ok
       - better setup of clockevents
      
      * tag 'arc-fixes-for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
        ARC: Use clockevents_config_and_register over clockevents_register_device
        ARC: Workaround spinlock livelock in SMP SystemC simulation
        ARC: Fix 32-bit wrap around in access_ok()
        ARC: Handle zero-overhead-loop in unaligned access handler
      815a4bb1
    • Gabor Juhos's avatar
      avr32: cast syscall_return to silence compiler warning · 395e73a2
      Gabor Juhos authored
      The patch fixes the following compiler warning:
          CC      arch/avr32/kernel/process.o
        arch/avr32/kernel/process.c: In function 'copy_thread':
        arch/avr32/kernel/process.c:292: warning: assignment makes integer \
        from pointer without a cast
      Signed-off-by: default avatarGabor Juhos <juhosg@openwrt.org>
      Acked-by: default avatarHans-Christian Egtvedt <egtvedt@samfundet.no>
      395e73a2
    • Gabor Juhos's avatar
      avr32: fix clockevents kernel warning · 1b0135b5
      Gabor Juhos authored
      Since commit 01426478
      (avr32: Use generic idle loop) the kernel throws the
      following warning on avr32:
      
        WARNING: at 900322e4 [verbose debug info unavailable]
        Modules linked in:
        CPU: 0 PID: 0 Comm: swapper Not tainted 3.12.0-rc2 #117
        task: 901c3ecc ti: 901c0000 task.ti: 901c0000
        PC is at cpu_idle_poll_ctrl+0x1c/0x38
        LR is at comparator_mode+0x3e/0x40
        pc : [<900322e4>]    lr : [<90014882>]    Not tainted
        sp : 901c1f74  r12: 00000000  r11: 901c74a0
        r10: 901d2510  r9 : 00000001  r8 : 901db4de
        r7 : 901c74a0  r6 : 00000001  r5 : 00410020  r4 : 901db574
        r3 : 00410024  r2 : 90206fe0  r1 : 00000000  r0 : 007f0000
        Flags: qvnzc
        Mode bits: hjmde....G
        CPU Mode: Supervisor
        Call trace:
         [<90039ede>] clockevents_set_mode+0x16/0x2e
         [<90039f00>] clockevents_shutdown+0xa/0x1e
         [<9003a078>] clockevents_exchange_device+0x58/0x70
         [<9003a78c>] tick_check_new_device+0x38/0x54
         [<9003a1a2>] clockevents_register_device+0x32/0x90
         [<900035c4>] time_init+0xa8/0x108
         [<90000520>] start_kernel+0x128/0x23c
      
      When the 'avr32_comparator' clockevent device is registered,
      the clockevent core sets the mode of that clockevent device
      to CLOCK_EVT_MODE_SHUTDOWN. Due to this, the 'comparator_mode'
      function calls the 'cpu_idle_poll_ctrl' to disables idle poll.
      This results in the aforementioned warning because the polling
      is not enabled yet.
      
      Change the code to only disable idle poll if it is enabled by
      the same function to avoid the warning.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarGabor Juhos <juhosg@openwrt.org>
      Acked-by: default avatarHans-Christian Egtvedt <egtvedt@samfundet.no>
      1b0135b5
    • Steven Rostedt's avatar
      avr32: use Kbuild infrastructure to handle the asm-generic headers · 46663d05
      Steven Rostedt authored
      Use kbuild to add asm-generic headers that do nothing, also remove the arch
      specific wrapper headers.
      
      This only affects headers that do nothing but include the generic
      equivalent. It does not touch any header that does a little more.
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarHans-Christian Egtvedt <egtvedt@samfundet.no>
      46663d05
  2. 29 Sep, 2013 10 commits
    • Linus Torvalds's avatar
      Linux 3.12-rc3 · 15c03dd4
      Linus Torvalds authored
      15c03dd4
    • Linus Torvalds's avatar
      Merge tag 'usb-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb · 30ceb4ec
      Linus Torvalds authored
      Pull USB fixes from Greg KH:
       "Here are a number of USB driver fixes for 3.12-rc3.
      
        These are all for host controller issues that have been reported, and
        there's a fix for an annoying error message that gets printed every
        time you remove a USB 3 device from the system that's been bugging me
        for a while"
      
      * tag 'usb-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
        usb: dwc3: add support for Merrifield
        USB: fsl/ehci: fix failure of checking PHY_CLK_VALID during reinitialization
        USB: Fix breakage in ffs_fs_mount()
        fsl/usb: Resolve PHY_CLK_VLD instability issue for ULPI phy
        usb/core/devio.c: Don't reject control message to endpoint with wrong direction bit
        usb: chipidea: USB_CHIPIDEA should depend on HAS_DMA
        usb: chipidea: udc: free pending TD at removal procedure
        usb: chipidea: imx: Add usb_phy_shutdown at probe's error path
        usb: chipidea: Fix memleak for ci->hw_bank.regmap when removal
        usb: chipidea: udc: fix the oops after rmmod gadget
        USB: fix PM config symbol in uhci-hcd, ehci-hcd, and xhci-hcd
        USB: OHCI: accept very late isochronous URBs
        USB: UHCI: accept very late isochronous URBs
        USB: iMX21: accept very late isochronous URBs
        usbcore: check usb device's state before sending a Set SEL control transfer
        xhci: Fix race between ep halt and URB cancellation
        usb: Fix xHCI host issues on remote wakeup.
        xhci: Ensure a command structure points to the correct trb on the command ring
        xhci: Fix oops happening after address device timeout
      30ceb4ec
    • Linus Torvalds's avatar
      Merge tag 'tty-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty · 26c019fc
      Linus Torvalds authored
      Pull tty/serial fixes from Greg KH:
       "Here are some serial at tty driver fixes for 3.12-rc3
      
        The serial driver fixes some kref leaks, documentation is moved to the
        proper places, and the tty and n_tty fixes resolve some reported
        regressions.  There is still one outstanding tty regression fix that
        isn't in here yet, as I want to test it out some more, it will be sent
        for 3.12-rc4 if it checks out"
      
      * tag 'tty-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
        tty: ar933x_uart: move devicetree binding documentation
        tty: Fix SIGTTOU not sent with tcflush()
        n_tty: Fix EOF push index when termios changes
        serial: pch_uart: remove unnecessary tty_port_tty_get
        serial: pch_uart: fix tty-kref leak in dma-rx path
        serial: pch_uart: fix tty-kref leak in rx-error path
        serial: tegra: fix tty-kref leak
      26c019fc
    • Linus Torvalds's avatar
      Merge tag 'staging-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging · 31795c40
      Linus Torvalds authored
      Pull staging fixes from Greg KH:
       "Here are some staging driver fixes, MAINTAINER updates, and a new
        device id.  All of these have been in the linux-next tree, and are
        pretty simple patches"
      
      * tag 'staging-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
        staging: r8188eu: Add new device ID
        staging: imx-drm: Fix probe failure
        staging: vt6656: [BUG] iwctl_siwencodeext return if device not open
        staging: vt6656: [BUG] main_usb.c oops on device_close move flag earlier.
        staging: vt6656: rxtx.c [BUG] s_vGetFreeContext dead lock on null apTD.
        Staging: rtl8192u: r819xU_cmdpkt: checking NULL value after doing dev_alloc_skb
        staging: usbip: Orphan usbip
        staging: r8188eu: Add files for new drive: Cocci spatch "noderef"
        staging: r8188eu: Cocci spatch "noderef"
        staging: octeon-usb: Cocci spatch "noderef"
        staging: r8188eu: Add files for new drive: Cocci spatch "noderef"
        MAINTAINERS: staging: dgnc and dgap drivers: add maintainer
        staging: lustre: Cocci spatch "noderef"
      31795c40
    • Linus Torvalds's avatar
      Merge tag 'driver-core-3.12-rc3' of... · 434ac47d
      Linus Torvalds authored
      Merge tag 'driver-core-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
      
      Pull driver core / sysfs fixes from Greg KH:
       "Here are 2 fixes for 3.12-rc3.  One fixes a sysfs problem with
        mounting caused by 3.12-rc1, and the other is a bug reported by the
        chromeos developers with the driver core.
      
        Both have been in linux-next for a bit"
      
      * tag 'driver-core-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
        driver core : Fix use after free of dev->parent in device_shutdown
        sysfs: Allow mounting without CONFIG_NET
      434ac47d
    • Linus Torvalds's avatar
      Merge tag 'char-misc-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc · c23c2234
      Linus Torvalds authored
      Pull char/misc driver fixes from Greg KH:
       "Here are some HyperV and MEI driver fixes for 3.12-rc3.  They resolve
        some issues that people have been reporting for them"
      
      * tag 'char-misc-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
        Drivers: hv: vmbus: Terminate vmbus version negotiation on timeout
        Drivers: hv: util: Correctly support ws2008R2 and earlier
        mei: cancel stall timers in mei_reset
        mei: bus: stop wait for read during cl state transition
        mei: make me client counters less error prone
      c23c2234
    • Linus Torvalds's avatar
      Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · cac66535
      Linus Torvalds authored
      Pull perf revert from Ingo Molnar:
       "This fixes the 'perf top' regression Markus Trippelsdorf reported"
      
      * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        Revert "perf symbols: Demangle cloned functions"
      cac66535
    • Linus Torvalds's avatar
      Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux · b97b869a
      Linus Torvalds authored
      Pull drm fixes from Dave Airlie:
       "Nothing too major, radeon still has some dpm changes for off by
        default.
      
        Radeon, intel, msm:
         - radeon: a few more dpm fixes (still off by default), uvd fixes
         - i915: runtime warn backtrace and regression fix
         - msm: iommu changes fallout"
      
      * 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (27 commits)
        drm/msm: use drm_gem_dumb_destroy helper
        drm/msm: deal with mach/iommu.h removal
        drm/msm: Remove iommu include from mdp4_kms.c
        drm/msm: Odd PTR_ERR usage
        drm/i915: Fix up usage of SHRINK_STOP
        drm/radeon: fix hdmi audio on DCE3.0/3.1 asics
        drm/i915: preserve pipe A quirk in i9xx_set_pipeconf
        drm/i915/tv: clear adjusted_mode.flags
        drm/i915/dp: increase i2c-over-aux retry interval on AUX DEFER
        drm/radeon/cik: fix overflow in vram fetch
        drm/radeon: add missing hdmi callbacks for rv6xx
        drm/i915: Use a temporary va_list for two-pass string handling
        drm/radeon/uvd: lower msg&fb buffer requirements on UVD3
        drm/radeon: disable tests/benchmarks if accel is disabled
        drm/radeon: don't set default clocks for SI when DPM is disabled
        drm/radeon/dpm/ci: filter clocks based on voltage/clk dep tables
        drm/radeon/dpm/si: filter clocks based on voltage/clk dep tables
        drm/radeon/dpm/ni: filter clocks based on voltage/clk dep tables
        drm/radeon/dpm/btc: filter clocks based on voltage/clk dep tables
        drm/radeon/dpm: fetch the max clk from voltage dep tables helper
        ...
      b97b869a
    • Ingo Molnar's avatar
      Revert "perf symbols: Demangle cloned functions" · 14951f22
      Ingo Molnar authored
      This reverts commit de95ab53.
      
      Markus Trippelsdorf reported that this commit broke 'perf top':
      
       > I just see a gray screen with no text at all. Sometimes the
       > following error messages are printed:
       >
       >  *** Error in `perf': invalid fastbin entry (free): 0x00000000029b18c0
       >  ***
       >  *** Error in `perf': malloc(): memory corruption (fast): 0x0000000000ee0b10 ***
      
      While this code is fixable, the commit itself fails on several levels:
      
       - it should have been a separate helper function
       - why the heck does it do strchr() twice
       - it casts a const char * over into char *
       - sloppy style
       - it's not even a regression fix!
      
      So lets revert it and re-try the patch in v3.13.
      Reported-by: default avatarMarkus Trippelsdorf <markus@trippelsdorf.de>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      14951f22
    • Dave Airlie's avatar
      Merge branch 'msm-fixes-3.12-rc2' of git://people.freedesktop.org/~robclark/linux into drm-fixes · 66544179
      Dave Airlie authored
      A small fix + deal with fallout of iommu changes + use new
      drm_gem_dumb_destroy helper.
      
      * 'msm-fixes-3.12-rc2' of git://people.freedesktop.org/~robclark/linux:
        drm/msm: use drm_gem_dumb_destroy helper
        drm/msm: deal with mach/iommu.h removal
        drm/msm: Remove iommu include from mdp4_kms.c
        drm/msm: Odd PTR_ERR usage
      66544179
  3. 28 Sep, 2013 8 commits