1. 06 Aug, 2015 28 commits
  2. 05 Aug, 2015 12 commits
    • Grigori Goronzy's avatar
      drm/radeon: fix HDP flushing · 8b72decc
      Grigori Goronzy authored
      commit 54e03986 upstream.
      
      This was regressed by commit 39e7f6f8, although I don't know of any
      actual issues caused by it.
      
      The storage domain is read without TTM locking now, but the lock
      never helped to prevent any races.
      Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
      Signed-off-by: default avatarGrigori Goronzy <greg@chown.ath.cx>
      Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8b72decc
    • Ian Munsie's avatar
      cxl: Fix off by one error allowing subsequent mmap page to be accessed · 8c980662
      Ian Munsie authored
      commit 10a5894f upstream.
      
      It was discovered that if a process mmaped their problem state area they
      were able to access one page more than expected, potentially allowing
      them to access the problem state area of an unrelated process.
      
      This was due to a simple off by one error in the mmap fault handler
      introduced in 0712dc7e ("cxl: Fix issues
      when unmapping contexts"), which is fixed in this patch.
      
      Fixes: 0712dc7e ("cxl: Fix issues when unmapping contexts")
      Signed-off-by: default avatarIan Munsie <imunsie@au1.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8c980662
    • Shreyas B. Prabhu's avatar
      powerpc/powernv: Fix race in updating core_idle_state · 55fbd98c
      Shreyas B. Prabhu authored
      commit b32aadc1 upstream.
      
      core_idle_state is maintained for each core. It uses 0-7 bits to track
      whether a thread in the core has entered fastsleep or winkle. 8th bit is
      used as a lock bit.
      The lock bit is set in these 2 scenarios-
       - The thread is first in subcore to wakeup from sleep/winkle.
       - If its the last thread in the core about to enter sleep/winkle
      
      While the lock bit is set, if any other thread in the core wakes up, it
      loops until the lock bit is cleared before proceeding in the wakeup
      path. This helps prevent race conditions w.r.t fastsleep workaround and
      prevents threads from switching to process context before core/subcore
      resources are restored.
      
      But, in the path to sleep/winkle entry, we currently don't check for
      lock-bit. This exposes us to following race when running with subcore
      on-
      
      First thread in the subcorea		Another thread in the same
      waking up		   		core entering sleep/winkle
      
      lwarx   r15,0,r14
      ori     r15,r15,PNV_CORE_IDLE_LOCK_BIT
      stwcx.  r15,0,r14
      [Code to restore subcore state]
      
      						lwarx   r15,0,r14
      						[clear thread bit]
      						stwcx.  r15,0,r14
      
      andi.   r15,r15,PNV_CORE_IDLE_THREAD_BITS
      stw     r15,0(r14)
      
      Here, after the thread entering sleep clears its thread bit in
      core_idle_state, the value is overwritten by the thread waking up.
      In such cases when the core enters fastsleep, code mistakes an idle
      thread as running. Because of this, the first thread waking up from
      fastsleep which is supposed to resync timebase skips it. So we can
      end up having a core with stale timebase value.
      
      This patch fixes the above race by looping on the lock bit even while
      entering the idle states.
      Signed-off-by: default avatarShreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
      Fixes: 7b54e9f213f76 'powernv/powerpc: Add winkle support for offline cpus'
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      55fbd98c
    • Rafael J. Wysocki's avatar
      ACPI / PNP: Reserve ACPI resources at the fs_initcall_sync stage · 39893e3b
      Rafael J. Wysocki authored
      commit 0294112e upstream.
      
      This effectively reverts the following three commits:
      
       7bc10388 ACPI / resources: free memory on error in add_region_before()
       0f1b414d ACPI / PNP: Avoid conflicting resource reservations
       b9a5e5e1 ACPI / init: Fix the ordering of acpi_reserve_resources()
      
      (commit b9a5e5e1 introduced regressions some of which, but not
      all, were addressed by commit 0f1b414d and commit 7bc10388
      was a fixup on top of the latter) and causes ACPI fixed hardware
      resources to be reserved at the fs_initcall_sync stage of system
      initialization.
      
      The story is as follows.  First, a boot regression was reported due
      to an apparent resource reservation ordering change after a commit
      that shouldn't lead to such changes.  Investigation led to the
      conclusion that the problem happened because acpi_reserve_resources()
      was executed at the device_initcall() stage of system initialization
      which wasn't strictly ordered with respect to driver initialization
      (and with respect to the initialization of the pcieport driver in
      particular), so a random change causing the device initcalls to be
      run in a different order might break things.
      
      The response to that was to attempt to run acpi_reserve_resources()
      as soon as we knew that ACPI would be in use (commit b9a5e5e1).
      However, that turned out to be too early, because it caused resource
      reservations made by the PNP system driver to fail on at least one
      system and that failure was addressed by commit 0f1b414d.
      
      That fix still turned out to be insufficient, though, because
      calling acpi_reserve_resources() before the fs_initcall stage of
      system initialization caused a boot regression to happen on the
      eCAFE EC-800-H20G/S netbook.  That meant that we only could call
      acpi_reserve_resources() at the fs_initcall initialization stage
      or later, but then we might just as well call it after the PNP
      initalization in which case commit 0f1b414d wouldn't be
      necessary any more.
      
      For this reason, the changes made by commit 0f1b414d are reverted
      (along with a memory leak fixup on top of that commit), the changes
      made by commit b9a5e5e1 that went too far are reverted too and
      acpi_reserve_resources() is changed into fs_initcall_sync, which
      will cause it to be executed after the PNP subsystem initialization
      (which is an fs_initcall) and before device initcalls (including
      the pcieport driver initialization) which should avoid the initial
      issue.
      
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=100581
      Link: http://marc.info/?t=143092384600002&r=1&w=2
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=99831
      Link: http://marc.info/?t=143389402600001&r=1&w=2
      Fixes: b9a5e5e1 "ACPI / init: Fix the ordering of acpi_reserve_resources()"
      Reported-by: default avatarRoland Dreier <roland@purestorage.com>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      39893e3b
    • Roger Quadros's avatar
      ARM: dts: am57xx-beagle-x15: Provide supply for usb2_phy2 · 934ab6eb
      Roger Quadros authored
      commit 9ab402ae upstream.
      
      Without this USB2 breaks if USB1 is disabled or USB1
      initializes after USB2 e.g. due to deferred probing.
      
      Fixes: 5a0f93c6 ("ARM: dts: Add am57xx-beagle-x15")
      Signed-off-by: default avatarRoger Quadros <rogerq@ti.com>
      Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      934ab6eb
    • Michal Hocko's avatar
      ext4: replace open coded nofail allocation in ext4_free_blocks() · ef505188
      Michal Hocko authored
      commit 7444a072 upstream.
      
      ext4_free_blocks is looping around the allocation request and mimics
      __GFP_NOFAIL behavior without any allocation fallback strategy. Let's
      remove the open coded loop and replace it with __GFP_NOFAIL. Without the
      flag the allocator has no way to find out never-fail requirement and
      cannot help in any way.
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.cz>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ef505188
    • Eryu Guan's avatar
      ext4: correctly migrate a file with a hole at the beginning · 47eb4b36
      Eryu Guan authored
      commit 8974fec7 upstream.
      
      Currently ext4_ind_migrate() doesn't correctly handle a file which
      contains a hole at the beginning of the file.  This caused the migration
      to be done incorrectly, and then if there is a subsequent following
      delayed allocation write to the "hole", this would reclaim the same data
      blocks again and results in fs corruption.
      
        # assmuing 4k block size ext4, with delalloc enabled
        # skip the first block and write to the second block
        xfs_io -fc "pwrite 4k 4k" -c "fsync" /mnt/ext4/testfile
      
        # converting to indirect-mapped file, which would move the data blocks
        # to the beginning of the file, but extent status cache still marks
        # that region as a hole
        chattr -e /mnt/ext4/testfile
      
        # delayed allocation writes to the "hole", reclaim the same data block
        # again, results in i_blocks corruption
        xfs_io -c "pwrite 0 4k" /mnt/ext4/testfile
        umount /mnt/ext4
        e2fsck -nf /dev/sda6
        ...
        Inode 53, i_blocks is 16, should be 8.  Fix? no
        ...
      Signed-off-by: default avatarEryu Guan <guaneryu@gmail.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      47eb4b36
    • Eryu Guan's avatar
      ext4: be more strict when migrating to non-extent based file · ca842bc9
      Eryu Guan authored
      commit d6f123a9 upstream.
      
      Currently the check in ext4_ind_migrate() is not enough before doing the
      real conversion:
      
      a) delayed allocated extents could bypass the check on eh->eh_entries
         and eh->eh_depth
      
      This can be demonstrated by this script
      
        xfs_io -fc "pwrite 0 4k" -c "pwrite 8k 4k" /mnt/ext4/testfile
        chattr -e /mnt/ext4/testfile
      
      where testfile has two extents but still be converted to non-extent
      based file format.
      
      b) only extent length is checked but not the offset, which would result
         in data lose (delalloc) or fs corruption (nodelalloc), because
         non-extent based file only supports at most (12 + 2^10 + 2^20 + 2^30)
         blocks
      
      This can be demostrated by
      
        xfs_io -fc "pwrite 5T 4k" /mnt/ext4/testfile
        chattr -e /mnt/ext4/testfile
        sync
      
      If delalloc is enabled, dmesg prints
        EXT4-fs warning (device dm-4): ext4_block_to_path:105: block 1342177280 > max in inode 53
        EXT4-fs (dm-4): Delayed block allocation failed for inode 53 at logical offset 1342177280 with max blocks 1 with error 5
        EXT4-fs (dm-4): This should not happen!! Data will be lost
      
      If delalloc is disabled, e2fsck -nf shows corruption
        Inode 53, i_size is 5497558142976, should be 4096.  Fix? no
      
      Fix the two issues by
      
      a) forcing all delayed allocation blocks to be allocated before checking
         eh->eh_depth and eh->eh_entries
      b) limiting the last logical block of the extent is within direct map
      Signed-off-by: default avatarEryu Guan <guaneryu@gmail.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ca842bc9
    • Lukas Czerner's avatar
      ext4: fix reservation release on invalidatepage for delalloc fs · bbc80299
      Lukas Czerner authored
      commit 9705acd6 upstream.
      
      On delalloc enabled file system on invalidatepage operation
      in ext4_da_page_release_reservation() we want to clear the delayed
      buffer and remove the extent covering the delayed buffer from the extent
      status tree.
      
      However currently there is a bug where on the systems with page size >
      block size we will always remove extents from the start of the page
      regardless where the actual delayed buffers are positioned in the page.
      This leads to the errors like this:
      
      EXT4-fs warning (device loop0): ext4_da_release_space:1225:
      ext4_da_release_space: ino 13, to_free 1 with only 0 reserved data
      blocks
      
      This however can cause data loss on writeback time if the file system is
      in ENOSPC condition because we're releasing reservation for someones
      else delayed buffer.
      
      Fix this by only removing extents that corresponds to the part of the
      page we want to invalidate.
      
      This problem is reproducible by the following fio receipt (however I was
      only able to reproduce it with fio-2.1 or older.
      
      [global]
      bs=8k
      iodepth=1024
      iodepth_batch=60
      randrepeat=1
      size=1m
      directory=/mnt/test
      numjobs=20
      [job1]
      ioengine=sync
      bs=1k
      direct=1
      rw=randread
      filename=file1:file2
      [job2]
      ioengine=libaio
      rw=randwrite
      direct=1
      filename=file1:file2
      [job3]
      bs=1k
      ioengine=posixaio
      rw=randwrite
      direct=1
      filename=file1:file2
      [job5]
      bs=1k
      ioengine=sync
      rw=randread
      filename=file1:file2
      [job7]
      ioengine=libaio
      rw=randwrite
      filename=file1:file2
      [job8]
      ioengine=posixaio
      rw=randwrite
      filename=file1:file2
      [job10]
      ioengine=mmap
      rw=randwrite
      bs=1k
      filename=file1:file2
      [job11]
      ioengine=mmap
      rw=randwrite
      direct=1
      filename=file1:file2
      Signed-off-by: default avatarLukas Czerner <lczerner@redhat.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      bbc80299
    • Nikolay Borisov's avatar
      ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp · 1fc56e88
      Nikolay Borisov authored
      commit c45653c3 upstream.
      
      Switch ext4 to using sb_getblk_gfp with GFP_NOFS added to fix possible
      deadlocks in the page writeback path.
      Signed-off-by: default avatarNikolay Borisov <kernel@kyup.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1fc56e88
    • Nikolay Borisov's avatar
      bufferhead: Add _gfp version for sb_getblk() · 52a0b6ce
      Nikolay Borisov authored
      commit bd7ade3c upstream.
      
      sb_getblk() is used during ext4 (and possibly other FSes) writeback
      paths. Sometimes such path require allocating memory and guaranteeing
      that such allocation won't block. Currently, however, there is no way
      to provide user flags for sb_getblk which could lead to deadlocks.
      
      This patch implements a sb_getblk_gfp with the only difference it can
      accept user-provided GFP flags.
      Signed-off-by: default avatarNikolay Borisov <kernel@kyup.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      52a0b6ce
    • Filipe Manana's avatar
      Btrfs: fix fsync data loss after append write · 895ee048
      Filipe Manana authored
      commit e4545de5 upstream.
      
      If we do an append write to a file (which increases its inode's i_size)
      that does not have the flag BTRFS_INODE_NEEDS_FULL_SYNC set in its inode,
      and the previous transaction added a new hard link to the file, which sets
      the flag BTRFS_INODE_COPY_EVERYTHING in the file's inode, and then fsync
      the file, the inode's new i_size isn't logged. This has the consequence
      that after the fsync log is replayed, the file size remains what it was
      before the append write operation, which means users/applications will
      not be able to read the data that was successsfully fsync'ed before.
      
      This happens because neither the inode item nor the delayed inode get
      their i_size updated when the append write is made - doing so would
      require starting a transaction in the buffered write path, something that
      we do not do intentionally for performance reasons.
      
      Fix this by making sure that when the flag BTRFS_INODE_COPY_EVERYTHING is
      set the inode is logged with its current i_size (log the in-memory inode
      into the log tree).
      
      This issue is not a recent regression and is easy to reproduce with the
      following test case for fstests:
      
        seq=`basename $0`
        seqres=$RESULT_DIR/$seq
        echo "QA output created by $seq"
      
        here=`pwd`
        tmp=/tmp/$$
        status=1	# failure is the default!
      
        _cleanup()
        {
                _cleanup_flakey
                rm -f $tmp.*
        }
        trap "_cleanup; exit \$status" 0 1 2 3 15
      
        # get standard environment, filters and checks
        . ./common/rc
        . ./common/filter
        . ./common/dmflakey
      
        # real QA test starts here
        _supported_fs generic
        _supported_os Linux
        _need_to_be_root
        _require_scratch
        _require_dm_flakey
        _require_metadata_journaling $SCRATCH_DEV
      
        _crash_and_mount()
        {
                # Simulate a crash/power loss.
                _load_flakey_table $FLAKEY_DROP_WRITES
                _unmount_flakey
                # Allow writes again and mount. This makes the fs replay its fsync log.
                _load_flakey_table $FLAKEY_ALLOW_WRITES
                _mount_flakey
        }
      
        rm -f $seqres.full
      
        _scratch_mkfs >> $seqres.full 2>&1
        _init_flakey
        _mount_flakey
      
        # Create the test file with some initial data and then fsync it.
        # The fsync here is only needed to trigger the issue in btrfs, as it causes the
        # the flag BTRFS_INODE_NEEDS_FULL_SYNC to be removed from the btrfs inode.
        $XFS_IO_PROG -f -c "pwrite -S 0xaa 0 32k" \
                        -c "fsync" \
                        $SCRATCH_MNT/foo | _filter_xfs_io
        sync
      
        # Add a hard link to our file.
        # On btrfs this sets the flag BTRFS_INODE_COPY_EVERYTHING on the btrfs inode,
        # which is a necessary condition to trigger the issue.
        ln $SCRATCH_MNT/foo $SCRATCH_MNT/bar
      
        # Sync the filesystem to force a commit of the current btrfs transaction, this
        # is a necessary condition to trigger the bug on btrfs.
        sync
      
        # Now append more data to our file, increasing its size, and fsync the file.
        # In btrfs because the inode flag BTRFS_INODE_COPY_EVERYTHING was set and the
        # write path did not update the inode item in the btree nor the delayed inode
        # item (in memory struture) in the current transaction (created by the fsync
        # handler), the fsync did not record the inode's new i_size in the fsync
        # log/journal. This made the data unavailable after the fsync log/journal is
        # replayed.
        $XFS_IO_PROG -c "pwrite -S 0xbb 32K 32K" \
                     -c "fsync" \
                     $SCRATCH_MNT/foo | _filter_xfs_io
      
        echo "File content after fsync and before crash:"
        od -t x1 $SCRATCH_MNT/foo
      
        _crash_and_mount
      
        echo "File content after crash and log replay:"
        od -t x1 $SCRATCH_MNT/foo
      
        status=0
        exit
      
      The expected file output before and after the crash/power failure expects the
      appended data to be available, which is:
      
        0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
        *
        0100000 bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
        *
        0200000
      Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
      Reviewed-by: default avatarLiu Bo <bo.li.liu@oracle.com>
      Signed-off-by: default avatarChris Mason <clm@fb.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      895ee048