1. 24 Apr, 2016 1 commit
    • Theodore Ts'o's avatar
      ext4: allow readdir()'s of large empty directories to be interrupted · 1f60fbe7
      Theodore Ts'o authored
      If a directory has a large number of empty blocks, iterating over all
      of them can take a long time, leading to scheduler warnings and users
      getting irritated when they can't kill a process in the middle of one
      of these long-running readdir operations.  Fix this by adding checks to
      ext4_readdir() and ext4_htree_fill_tree().
      
      This was reverted earlier due to a typo in the original commit where I
      experimented with using signal_pending() instead of
      fatal_signal_pending().  The test was in the wrong place if we were
      going to return signal_pending() since we would end up returning
      duplicant entries.  See 9f2394c9 for a more detailed explanation.
      
      Added fix as suggested by Linus to check for signal_pending() in
      in the filldir() functions.
      Reported-by: default avatarBenjamin LaHaise <bcrl@kvack.org>
      Google-Bug-Id: 27880676
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      1f60fbe7
  2. 18 Apr, 2016 1 commit
  3. 17 Apr, 2016 5 commits
  4. 16 Apr, 2016 7 commits
  5. 15 Apr, 2016 17 commits
  6. 14 Apr, 2016 9 commits
    • Mike Snitzer's avatar
      dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros · 9567366f
      Mike Snitzer authored
      The READ_LOCK macro was incorrectly returning -EINVAL if
      dm_bm_is_read_only() was true -- it will always be true once the cache
      metadata transitions to read-only by dm_cache_metadata_set_read_only().
      
      Wrap READ_LOCK and WRITE_LOCK multi-statement macros in do {} while(0).
      Also, all accesses of the 'cmd' argument passed to these related macros
      are now encapsulated in parenthesis.
      
      A follow-up patch can be developed to eliminate the use of macros in
      favor of pure C code.  Avoiding that now given that this needs to apply
      to stable@.
      Reported-by: default avatarBen Hutchings <ben@decadent.org.uk>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Fixes: d14fcf3d ("dm cache: make sure every metadata function checks fail_io")
      Cc: stable@vger.kernel.org
      9567366f
    • Keith Busch's avatar
      NVMe: Always use MSI/MSI-x interrupts · a5229050
      Keith Busch authored
      Multiple users have reported device initialization failure due the driver
      not receiving legacy PCI interrupts. This is not unique to any particular
      controller, but has been observed on multiple platforms.
      
      There have been no issues reported or observed when with message signaled
      interrupts, so this patch attempts to use MSI-x during initialization,
      falling back to MSI. If that fails, legacy would become the default.
      
      The setup_io_queues error handling had to change as a result: the admin
      queue's msix_entry used to be initialized to the legacy IRQ. The case
      where nr_io_queues is 0 would fail request_irq when setting up the admin
      queue's interrupt since re-enabling MSI-x fails with 0 vectors, leaving
      the admin queue's msix_entry invalid. Instead, return success immediately.
      Reported-by: default avatarTim Muhlemmer <muhlemmer@gmail.com>
      Reported-by: default avatarJon Derrick <jonathan.derrick@intel.com>
      Signed-off-by: default avatarKeith Busch <keith.busch@intel.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      a5229050
    • Linus Torvalds's avatar
      /proc/iomem: only expose physical resource addresses to privileged users · 51d7b120
      Linus Torvalds authored
      In commit c4004b02 ("x86: remove the kernel code/data/bss resources
      from /proc/iomem") I was hoping to remove the phyiscal kernel address
      data from /proc/iomem entirely, but that had to be reverted because some
      system programs actually use it.
      
      This limits all the detailed resource information to properly
      credentialed users instead.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      51d7b120
    • Linus Torvalds's avatar
      pci-sysfs: use proper file capability helper function · ab0fa82b
      Linus Torvalds authored
      The PCI config access checked the file capabilities correctly, but used
      the itnernal security capability check rather than the helper function
      that is actually meant for that.
      
      The security_capable() has unusual return values and is not meant to be
      used elsewhere (the only other use is in the capability checking
      functions that we actually intend people to use, and this odd PCI usage
      really stood out when looking around the capability code.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ab0fa82b
    • Linus Torvalds's avatar
      Make file credentials available to the seqfile interfaces · 34dbbcdb
      Linus Torvalds authored
      A lot of seqfile users seem to be using things like %pK that uses the
      credentials of the current process, but that is actually completely
      wrong for filesystem interfaces.
      
      The unix semantics for permission checking files is to check permissions
      at _open_ time, not at read or write time, and that is not just a small
      detail: passing off stdin/stdout/stderr to a suid application and making
      the actual IO happen in privileged context is a classic exploit
      technique.
      
      So if we want to be able to look at permissions at read time, we need to
      use the file open credentials, not the current ones.  Normal file
      accesses can just use "f_cred" (or any of the helper functions that do
      that, like file_ns_capable()), but the seqfile interfaces do not have
      any such options.
      
      It turns out that seq_file _does_ save away the user_ns information of
      the file, though.  Since user_ns is just part of the full credential
      information, replace that special case with saving off the cred pointer
      instead, and suddenly seq_file has all the permission information it
      needs.
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      34dbbcdb
    • Linus Torvalds's avatar
      Revert "x86: remove the kernel code/data/bss resources from /proc/iomem" · 4046d6e8
      Linus Torvalds authored
      This reverts commit c4004b02.
      
      Sadly, my hope that nobody would actually use the special kernel entries
      in /proc/iomem were dashed by kexec.  Which reads /proc/iomem explicitly
      to find the kernel base address.  Nasty.
      
      Anyway, that means we can't do the sane and simple thing and just remove
      the entries, and we'll instead have to mask them out based on permissions.
      Reported-by: default avatarZhengyu Zhang <zhezhang@redhat.com>
      Reported-by: default avatarDave Young <dyoung@redhat.com>
      Reported-by: default avatarFreeman Zhang <freeman.zhang1992@gmail.com>
      Reported-by: default avatarEmrah Demir <ed@abdsec.com>
      Reported-by: default avatarBaoquan He <bhe@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4046d6e8
    • Helge Deller's avatar
      parisc: Fix ftrace function tracer · 366dd4ea
      Helge Deller authored
      Fix the FTRACE function tracer for 32- and 64-bit kernel.
      The former code was horribly broken.
      
      Reimplement most coding in assembly and utilize optimizations, e.g. put
      mcount() and ftrace_stub() into one L1 cacheline.
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      366dd4ea
    • Toshi Kani's avatar
      pmem: fix BUG() error in pmem.h:48 on X86_32 · cba2e47a
      Toshi Kani authored
      After 'commit fc0c2028 ("x86, pmem: use memcpy_mcsafe()
      for memcpy_from_pmem()")', probing a PMEM device hits the BUG()
      error below on X86_32 kernel.
      
       kernel BUG at include/linux/pmem.h:48!
      
      memcpy_from_pmem() calls arch_memcpy_from_pmem(), which is
      unimplemented since CONFIG_ARCH_HAS_PMEM_API is undefined on
      X86_32.
      
      Fix the BUG() error by adding default_memcpy_from_pmem().
      Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
      Signed-off-by: default avatarToshi Kani <toshi.kani@hpe.com>
      Signed-off-by: default avatarRoss Zwisler <ross.zwisler@linux.intel.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
      cba2e47a
    • Stefan Agner's avatar
      pwm: fsl-ftm: Use flat regmap cache · ad06fdee
      Stefan Agner authored
      Use flat regmap cache to avoid lockdep warning at probe:
      
      [    0.697285] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2755 lockdep_trace_alloc+0x15c/0x160()
      [    0.697449] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
      
      The RB-tree regmap cache needs to allocate new space on first writes.
      However, allocations in an atomic context (e.g. when a spinlock is held)
      are not allowed. The function regmap_write calls map->lock, which
      acquires a spinlock in the fast_io case. Since the pwm-fsl-ftm driver
      uses MMIO, the regmap bus of type regmap_mmio is being used which has
      fast_io set to true.
      
      The MMIO space of the pwm-fsl-ftm driver is reasonable condense, hence
      using the much faster flat regmap cache is anyway the better choice.
      Signed-off-by: default avatarStefan Agner <stefan@agner.ch>
      Cc: Mark Brown <broonie@kernel.org>
      Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
      ad06fdee