1. 23 Aug, 2010 2 commits
    • Dave Chinner's avatar
      radix-tree: radix_tree_range_tag_if_tagged() can set incorrect tags · 144dcfc0
      Dave Chinner authored
      Commit ebf8aa44 ("radix-tree:
      omplement function radix_tree_range_tag_if_tagged") does not safely
      set tags on on intermediate tree nodes. The code walks down the tree
      setting tags before it has fully resolved the path to the leaf under
      the assumption there will be a leaf slot with the tag set in the
      range it is searching.
      
      Unfortunately, this is not a valid assumption - we can abort after
      setting a tag on an intermediate node if we overrun the number of
      tags we are allowed to set in a batch, or stop scanning because we
      we have passed the last scan index before we reach a leaf slot with
      the tag we are searching for set.
      
      As a result, we can leave the function with tags set on intemediate
      nodes which can be tripped over later by tag-based lookups. The
      result of these stale tags is that lookup may end prematurely or
      livelock because the lookup cannot make progress.
      
      The fix for the problem involves reocrding the traversal path we
      take to the leaf nodes, and only propagating the tags back up the
      tree once the tag is set in the leaf node slot. We are already
      recording the path for efficient traversal, so there is no
      additional overhead to do the intermediately node tag setting in
      this manner.
      
      This fixes a radix tree lookup livelock triggered by the new
      writeback sync livelock avoidance code introduced in commit
      f446daae ("mm: implement writeback
      livelock avoidance using page tagging").
      Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
      Acked-by: default avatarJan Kara <jack@suse.cz>
      144dcfc0
    • Dave Chinner's avatar
      radix-tree: clear all tags in radix_tree_node_rcu_free · b6dd0865
      Dave Chinner authored
      Commit f446daae ("mm: implement
      writeback livelock avoidance using page tagging") introduced a new
      radix tree tag, increasing the number of tags in each node from 2 to
      3. It did not, however, fix up the code in
      radix_tree_node_rcu_free() that cleans up after radix_tree_shrink()
      and hence could leave stray tags set in the new tag array.
      
      The result is that the livelock avoidance code added in the the
      above commit would hit stale tags when doing tag based lookups,
      resulting in livelocks when trying to traverse the tree.
      
      Fix this problem in radix_tree_node_rcu_free() so it doesn't happen
      again in the future by using a loop to walk all the tags up to
      RADIX_TREE_MAX_TAGS to clear the stray tags radix_tree_shrink()
      leaves behind.
      Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
      Acked-by: default avatarNick Piggin <npiggin@kernel.dk>
      Acked-by: default avatarJan Kara <jack@suse.cz>
      b6dd0865
  2. 16 Aug, 2010 5 commits
    • Linus Torvalds's avatar
      Linux 2.6.36-rc1 · da5cabf8
      Linus Torvalds authored
      da5cabf8
    • Linus Torvalds's avatar
      Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 · 2245ba2a
      Linus Torvalds authored
      * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
        gcc-4.6: ACPI: fix unused but set variables in ACPI
        ACPI thermal: make procfs I/F depend on CONFIG_ACPI_PROCFS
        ACPI video: make procfs I/F depend on CONFIG_ACPI_PROCFS
        ACPI processor: remove deprecated ACPI procfs I/F
        ACPI power_resource: remove unused procfs I/F
        ACPI: remove deprecated ACPI procfs I/F
        ACPI: introduce drivers/acpi/sysfs.c
        ACPI: introduce module parameter acpi.aml_debug_output
        ACPI: introduce drivers/acpi/debugfs.c
        ACPI, APEI, ERST debug support
        ACPI, APEI, Manage GHES as platform devices
        ACPI, APEI, Rename CPER and GHES severity constants
        ACPI, APEI, Fix a typo of error path of apei_resources_request
        ACPI / ACPICA: Fix reference counting problems with GPE handlers
        ACPI: Add the check of ADR flag in course of finding ACPI handle for PCI device
        ACPI / Sleep: Drop acpi_suspend_finish()
        ACPI / Sleep: Consolidate suspend and hibernation routines
        ACPI / Wakeup: Simplify enabling of wakeup devices
        ACPI / Sleep: Rework enabling wakeup devices
        ACPI / Sleep: Free NVS copy if suspending of devices fails
      
      Fixed up totally buggered "ACPI: fix unused but set variables in ACPI"
      patch that doesn't even compile in the merge.
      
      Thanks to Sedat Dilek <sedat.dilek@googlemail.com> for noticing the
      breakage before I even pulled.  And a big "Grrr.." at Len for not even
      bothering to compile the tree before asking me to pull.
      2245ba2a
    • Linus Torvalds's avatar
      Merge git://git.infradead.org/iommu-2.6 · e2e96c66
      Linus Torvalds authored
      * git://git.infradead.org/iommu-2.6:
        intel-iommu: Fix 32-bit build warning with __cmpxchg()
        intr-remap: allow disabling source id checking
      e2e96c66
    • Linus Torvalds's avatar
      Merge git://git.infradead.org/mtd-2.6 · 7355a5a6
      Linus Torvalds authored
      * git://git.infradead.org/mtd-2.6:
        mtd/nand_ids: Fix buswidth
        mtd/m25p80: fix test for end of loop
        mtd/m25p80: retlen is never NULL
        MIPS: Fix gen_nand probe structures contents
        gen_nand: Test if nr_chips field is valid
        BFIN: Fix gen_nand probe structures contents
        nand/denali: move all hardware initialization work to denali_hw_init
        nand/denali: Add a page check in denali_read_page & denali_read_page_raw
        nand/denali: use cpu_relax() while waiting for hardware interrupt
        nand/denali: change read_status function method
        nand/denali: Fixed check patch warnings
        ARM: Fix gen_nand probe structures contents
        mtd/nand_base: fix kernel-doc warnings & typos
        nand/denali: use dev_xx debug function to replace nand_dbg_print and some printk
        nand/denali: Fixed handle ECC error bugs
        nand/denali: use iowrite32() to replace denali_write32()
        nand/denali: Fixed probe function bugs
      7355a5a6
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile · 7a1b29a8
      Linus Torvalds authored
      * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
        arch/tile: don't validate CROSS_COMPILE needlessly
        arch/tile: export only COMMAND_LINE_SIZE to userspace.
        arch/tile: rename ARCH_KMALLOC_MINALIGN to ARCH_DMA_MINALIGN
        arch/tile: Rename the hweight() implementations to __arch_hweight()
        arch/tile: extend syscall ABI to set r1 on return as well.
        arch/tile: Various cleanups.
        arch/tile: support backtracing on TILE-Gx
        arch/tile: Fix a couple of issues with the COMPAT code for TILE-Gx.
        arch/tile: Use separate, better minsec values for clocksource and sched_clock.
        arch/tile: correct a bug in freeing bootmem by VA for the optional second initrd.
        arch: tile: mm: pgtable.c: Removed duplicated #include
        arch: tile: kernel/proc.c Removed duplicated #include
        Add fanotify syscalls to <asm-generic/unistd.h>.
        arch/tile: support new kunmap_atomic() naming convention.
        tile: remove unused ISA_DMA_THRESHOLD define
      
      Conflicts in arch/tile/configs/tile_defconfig (pick the mainline version
      with the reduced defconfig).
      7a1b29a8
  3. 15 Aug, 2010 26 commits
  4. 14 Aug, 2010 7 commits