1. 01 11月, 2011 1 次提交
    • D
      oom: remove oom_disable_count · c9f01245
      David Rientjes 提交于
      This removes mm->oom_disable_count entirely since it's unnecessary and
      currently buggy.  The counter was intended to be per-process but it's
      currently decremented in the exit path for each thread that exits, causing
      it to underflow.
      
      The count was originally intended to prevent oom killing threads that
      share memory with threads that cannot be killed since it doesn't lead to
      future memory freeing.  The counter could be fixed to represent all
      threads sharing the same mm, but it's better to remove the count since:
      
       - it is possible that the OOM_DISABLE thread sharing memory with the
         victim is waiting on that thread to exit and will actually cause
         future memory freeing, and
      
       - there is no guarantee that a thread is disabled from oom killing just
         because another thread sharing its mm is oom disabled.
      Signed-off-by: NDavid Rientjes <rientjes@google.com>
      Reported-by: NOleg Nesterov <oleg@redhat.com>
      Reviewed-by: NOleg Nesterov <oleg@redhat.com>
      Cc: Ying Han <yinghan@google.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c9f01245
  2. 07 8月, 2011 2 次提交
    • L
      vfs: show O_CLOEXE bit properly in /proc/<pid>/fdinfo/<fd> files · 1117f72e
      Linus Torvalds 提交于
      The CLOEXE bit is magical, and for performance (and semantic) reasons we
      don't actually maintain it in the file descriptor itself, but in a
      separate bit array.  Which means that when we show f_flags, the CLOEXE
      status is shown incorrectly: we show the status not as it is now, but as
      it was when the file was opened.
      
      Fix that by looking up the bit properly in the 'fdt->close_on_exec' bit
      array.
      
      Uli needs this in order to re-implement the pfiles program:
      
        "For normal file descriptors (not sockets) this was the last piece of
         information which wasn't available.  This is all part of my 'give
         Solaris users no reason to not switch' effort.  I intend to offer the
         code to the util-linux-ng maintainers."
      Requested-by: NUlrich Drepper <drepper@akkadia.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      1117f72e
    • L
      oom_ajd: don't use WARN_ONCE, just use printk_once · c2142704
      Linus Torvalds 提交于
      WARN_ONCE() is very annoying, in that it shows the stack trace that we
      don't care about at all, and also triggers various user-level "kernel
      oopsed" logic that we really don't care about.  And it's not like the
      user can do anything about the applications (sshd) in question, it's a
      distro issue.
      
      Requested-by: Andi Kleen <andi@firstfloor.org> (and many others)
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c2142704
  3. 27 7月, 2011 1 次提交
    • V
      proc: fix a race in do_io_accounting() · 293eb1e7
      Vasiliy Kulikov 提交于
      If an inode's mode permits opening /proc/PID/io and the resulting file
      descriptor is kept across execve() of a setuid or similar binary, the
      ptrace_may_access() check tries to prevent using this fd against the
      task with escalated privileges.
      
      Unfortunately, there is a race in the check against execve().  If
      execve() is processed after the ptrace check, but before the actual io
      information gathering, io statistics will be gathered from the
      privileged process.  At least in theory this might lead to gathering
      sensible information (like ssh/ftp password length) that wouldn't be
      available otherwise.
      
      Holding task->signal->cred_guard_mutex while gathering the io
      information should protect against the race.
      
      The order of locking is similar to the one inside of ptrace_attach():
      first goes cred_guard_mutex, then lock_task_sighand().
      Signed-off-by: NVasiliy Kulikov <segoon@openwall.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: <stable@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      293eb1e7
  4. 26 7月, 2011 1 次提交
    • D
      oom: make deprecated use of oom_adj more verbose · be8f684d
      David Rientjes 提交于
      /proc/pid/oom_adj is deprecated and scheduled for removal in August 2012
      according to Documentation/feature-removal-schedule.txt.
      
      This patch makes the warning more verbose by making it appear as a more
      serious problem (the presence of a stack trace and being multiline should
      attract more attention) so that applications still using the old interface
      can get fixed.
      
      Very popular users of the old interface have been converted since the oom
      killer rewrite has been introduced.  udevd switched to the
      /proc/pid/oom_score_adj interface for v162, kde switched in 4.6.1, and
      opensshd switched in 5.7p1.
      
      At the start of 2012, this should be changed into a WARN() to emit all
      such incidents and then finally remove the tunable in August 2012 as
      scheduled.
      Signed-off-by: NDavid Rientjes <rientjes@google.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      be8f684d
  5. 21 7月, 2011 1 次提交
  6. 20 7月, 2011 3 次提交
  7. 29 6月, 2011 1 次提交
  8. 23 6月, 2011 1 次提交
  9. 20 6月, 2011 1 次提交
  10. 27 5月, 2011 4 次提交
    • C
      arch/tile: more /proc and /sys file support · f133ecca
      Chris Metcalf 提交于
      This change introduces a few of the less controversial /proc and
      /proc/sys interfaces for tile, along with sysfs attributes for
      various things that were originally proposed as /proc/tile files.
      It also adjusts the "hardwall" proc API.
      
      Arnd Bergmann reviewed the initial arch/tile submission, which
      included a complete set of all the /proc/tile and /proc/sys/tile
      knobs that we had added in a somewhat ad hoc way during initial
      development, and provided feedback on where most of them should go.
      
      One knob turned out to be similar enough to the existing
      /proc/sys/debug/exception-trace that it was re-implemented to use
      that model instead.
      
      Another knob was /proc/tile/grid, which reported the "grid" dimensions
      of a tile chip (e.g. 8x8 processors = 64-core chip).  Arnd suggested
      looking at sysfs for that, so this change moves that information
      to a pair of sysfs attributes (chip_width and chip_height) in the
      /sys/devices/system/cpu directory.  We also put the "chip_serial"
      and "chip_revision" information from our old /proc/tile/board file
      as attributes in /sys/devices/system/cpu.
      
      Other information collected via hypervisor APIs is now placed in
      /sys/hypervisor.  We create a /sys/hypervisor/type file (holding the
      constant string "tilera") to be parallel with the Xen use of
      /sys/hypervisor/type holding "xen".  We create three top-level files,
      "version" (the hypervisor's own version), "config_version" (the
      version of the configuration file), and "hvconfig" (the contents of
      the configuration file).  The remaining information from our old
      /proc/tile/board and /proc/tile/switch files becomes an attribute
      group appearing under /sys/hypervisor/board/.
      
      Finally, after some feedback from Arnd Bergmann for the previous
      version of this patch, the /proc/tile/hardwall file is split up into
      two conceptual parts.  First, a directory /proc/tile/hardwall/ which
      contains one file per active hardwall, each file named after the
      hardwall's ID and holding a cpulist that says which cpus are enclosed by
      the hardwall.  Second, a /proc/PID file "hardwall" that is either
      empty (for non-hardwall-using processes) or contains the hardwall ID.
      
      Finally, this change pushes the /proc/sys/tile/unaligned_fixup/
      directory, with knobs controlling the kernel code for handling the
      fixup of unaligned exceptions.
      Reviewed-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NChris Metcalf <cmetcalf@tilera.com>
      f133ecca
    • K
      proc: put check_mem_permission after __get_free_page in mem_write · 30cd8903
      KOSAKI Motohiro 提交于
      It whould be better if put check_mem_permission after __get_free_page in
      mem_write, to be same as function mem_read.
      
      Hugh Dickins explained the reason.
      
          check_mem_permission gets a reference to the mm.  If we __get_free_page
          after check_mem_permission, imagine what happens if the system is out
          of memory, and the mm we're looking at is selected for killing by the
          OOM killer: while we wait in __get_free_page for more memory, no memory
          is freed from the selected mm because it cannot reach exit_mmap while
          we hold that reference.
      Reported-by: NJovi Zhang <bookjovi@gmail.com>
      Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Acked-by: NHugh Dickins <hughd@google.com>
      Reviewed-by: NStephen Wilson <wilsons@start.ca>
      Cc: Alexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      30cd8903
    • A
      fs/proc: convert to kstrtoX() · 0a8cb8e3
      Alexey Dobriyan 提交于
      Convert fs/proc/ from strict_strto*() to kstrto*() functions.
      Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0a8cb8e3
    • J
      mm: extract exe_file handling from procfs · 38646013
      Jiri Slaby 提交于
      Setup and cleanup of mm_struct->exe_file is currently done in fs/proc/.
      This was because exe_file was needed only for /proc/<pid>/exe.  Since we
      will need the exe_file functionality also for core dumps (so core name can
      contain full binary path), built this functionality always into the
      kernel.
      
      To achieve that move that out of proc FS to the kernel/ where in fact it
      should belong.  By doing that we can make dup_mm_exe_file static.  Also we
      can drop linux/proc_fs.h inclusion in fs/exec.c and kernel/fork.c.
      Signed-off-by: NJiri Slaby <jslaby@suse.cz>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      38646013
  11. 11 5月, 2011 1 次提交
    • E
      ns: proc files for namespace naming policy. · 6b4e306a
      Eric W. Biederman 提交于
      Create files under /proc/<pid>/ns/ to allow controlling the
      namespaces of a process.
      
      This addresses three specific problems that can make namespaces hard to
      work with.
      - Namespaces require a dedicated process to pin them in memory.
      - It is not possible to use a namespace unless you are the child
        of the original creator.
      - Namespaces don't have names that userspace can use to talk about
        them.
      
      The namespace files under /proc/<pid>/ns/ can be opened and the
      file descriptor can be used to talk about a specific namespace, and
      to keep the specified namespace alive.
      
      A namespace can be kept alive by either holding the file descriptor
      open or bind mounting the file someplace else.  aka:
      mount --bind /proc/self/ns/net /some/filesystem/path
      mount --bind /proc/self/fd/<N> /some/filesystem/path
      
      This allows namespaces to be named with userspace policy.
      
      It requires additional support to make use of these filedescriptors
      and that will be comming in the following patches.
      Acked-by: NDaniel Lezcano <daniel.lezcano@free.fr>
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      6b4e306a
  12. 19 4月, 2011 1 次提交
  13. 31 3月, 2011 1 次提交
  14. 24 3月, 2011 12 次提交
  15. 10 3月, 2011 1 次提交
  16. 14 1月, 2011 4 次提交
  17. 07 1月, 2011 4 次提交
    • N
      fs: provide rcu-walk aware permission i_ops · b74c79e9
      Nick Piggin 提交于
      Signed-off-by: NNick Piggin <npiggin@kernel.dk>
      b74c79e9
    • N
      fs: rcu-walk aware d_revalidate method · 34286d66
      Nick Piggin 提交于
      Require filesystems be aware of .d_revalidate being called in rcu-walk
      mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
      -ECHILD from all implementations.
      Signed-off-by: NNick Piggin <npiggin@kernel.dk>
      34286d66
    • N
      fs: dcache reduce branches in lookup path · fb045adb
      Nick Piggin 提交于
      Reduce some branches and memory accesses in dcache lookup by adding dentry
      flags to indicate common d_ops are set, rather than having to check them.
      This saves a pointer memory access (dentry->d_op) in common path lookup
      situations, and saves another pointer load and branch in cases where we
      have d_op but not the particular operation.
      
      Patched with:
      
      git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i
      Signed-off-by: NNick Piggin <npiggin@kernel.dk>
      fb045adb
    • N
      fs: change d_delete semantics · fe15ce44
      Nick Piggin 提交于
      Change d_delete from a dentry deletion notification to a dentry caching
      advise, more like ->drop_inode. Require it to be constant and idempotent,
      and not take d_lock. This is how all existing filesystems use the callback
      anyway.
      
      This makes fine grained dentry locking of dput and dentry lru scanning
      much simpler.
      Signed-off-by: NNick Piggin <npiggin@kernel.dk>
      fe15ce44