Commit Graph

596 Commits

Author SHA1 Message Date
Al Viro 3174c21b74 Move junk from proc_fs.h to fs/proc/internal.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:01 -04:00
James Morris 73fbad283c Merge branch 'next' into for-linus 2009-06-11 11:03:14 +10:00
Linus Torvalds 99e97b860e Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: fix typo in sched-rt-group.txt file
  ftrace: fix typo about map of kernel priority in ftrace.txt file.
  sched: properly define the sched_group::cpumask and sched_domain::span fields
  sched, timers: cleanup avenrun users
  sched, timers: move calc_load() to scheduler
  sched: Don't export sched_mc_power_savings on multi-socket single core system
  sched: emit thread info flags with stack trace
  sched: rt: document the risk of small values in the bandwidth settings
  sched: Replace first_cpu() with cpumask_first() in ILB nomination code
  sched: remove extra call overhead for schedule()
  sched: use group_first_cpu() instead of cpumask_first(sched_group_cpus())
  wait: don't use __wake_up_common()
  sched: Nominate a power-efficient ilb in select_nohz_balancer()
  sched: Nominate idle load balancer from a semi-idle package.
  sched: remove redundant hierarchy walk in check_preempt_wakeup
2009-06-10 15:32:59 -07:00
James Morris 0b4ec6e4e0 Merge branch 'master' into next 2009-06-09 09:27:53 +10:00
KOSAKI Motohiro bd6daba909 procfs: make errno values consistent when open pident vs exit(2) race occurs
proc_pident_instantiate() has following call flow.

proc_pident_lookup()
  proc_pident_instantiate()
    proc_pid_make_inode()

And, proc_pident_lookup() has following error handling.

	const struct pid_entry *p, *last;
	error = ERR_PTR(-ENOENT);
	if (!task)
		goto out_no_task;

Then, proc_pident_instantiate should return ENOENT too when racing against
exit(2) occur.

EINAL has two bad reason.
  - it implies caller is wrong. bad the race isn't caller's mistake.
  - man 2 open don't explain EINVAL. user often don't handle it.

Note: Other proc_pid_make_inode() caller already use ENOENT properly.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29 08:40:02 -07:00
James Morris 2c9e703c61 Merge branch 'master' into next
Conflicts:
	fs/exec.c

Removed IMA changes (the IMA checks are now performed via may_open()).

Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 18:40:59 +10:00
Thomas Gleixner 2d02494f5a sched, timers: cleanup avenrun users
avenrun is an rough estimate so we don't have to worry about
consistency of the three avenrun values. Remove the xtime lock
dependency and provide a function to scale the values. Cleanup the
users.

[ Impact: cleanup ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
2009-05-15 15:32:45 +02:00
David Howells 107db7c7dd CRED: Guard the setprocattr security hook against ptrace
Guard the setprocattr security hook against ptrace by taking the target task's
cred_guard_mutex around it.  The problem is that setprocattr() may otherwise
note the lack of a debugger, and then perform an action on that basis whilst
letting a debugger attach between the two points.  Holding cred_guard_mutex
across the test and the action prevents ptrace_attach() from doing that.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-11 08:15:39 +10:00
Al Viro 6f5bbff9a1 Convert obvious places to deactivate_locked_super()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:40 -04:00
Jake Edge f83ce3e6b0 proc: avoid information leaks to non-privileged processes
By using the same test as is used for /proc/pid/maps and /proc/pid/smaps,
only allow processes that can ptrace() a given process to see information
that might be used to bypass address space layout randomization (ASLR).
These include eip, esp, wchan, and start_stack in /proc/pid/stat as well
as the non-symbolic output from /proc/pid/wchan.

ASLR can be bypassed by sampling eip as shown by the proof-of-concept
code at http://code.google.com/p/fuzzyaslr/ As part of a presentation
(http://www.cr0.org/paper/to-jt-linux-alsr-leak.pdf) esp and wchan were
also noted as possibly usable information leaks as well.  The
start_stack address also leaks potentially useful information.

Cc: Stable Team <stable@kernel.org>
Signed-off-by: Jake Edge <jake@lwn.net>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-04 15:14:23 -07:00
KOSAKI Motohiro 00a62ce91e mm: fix Committed_AS underflow on large NR_CPUS environment
The Committed_AS field can underflow in certain situations:

>         # while true; do cat /proc/meminfo  | grep _AS; sleep 1; done | uniq -c
>               1 Committed_AS: 18446744073709323392 kB
>              11 Committed_AS: 18446744073709455488 kB
>               6 Committed_AS:    35136 kB
>               5 Committed_AS: 18446744073709454400 kB
>               7 Committed_AS:    35904 kB
>               3 Committed_AS: 18446744073709453248 kB
>               2 Committed_AS:    34752 kB
>               9 Committed_AS: 18446744073709453248 kB
>               8 Committed_AS:    34752 kB
>               3 Committed_AS: 18446744073709320960 kB
>               7 Committed_AS: 18446744073709454080 kB
>               3 Committed_AS: 18446744073709320960 kB
>               5 Committed_AS: 18446744073709454080 kB
>               6 Committed_AS: 18446744073709320960 kB

Because NR_CPUS can be greater than 1000 and meminfo_proc_show() does
not check for underflow.

But NR_CPUS proportional isn't good calculation.  In general,
possibility of lock contention is proportional to the number of online
cpus, not theorical maximum cpus (NR_CPUS).

The current kernel has generic percpu-counter stuff.  using it is right
way.  it makes code simplify and percpu_counter_read_positive() don't
make underflow issue.

Reported-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@kernel.org>		[All kernel versions]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:10 -07:00
Vitaly Mayatskikh 0816178638 pagemap: require aligned-length, non-null reads of /proc/pid/pagemap
The intention of commit aae8679b0e
("pagemap: fix bug in add_to_pagemap, require aligned-length reads of
/proc/pid/pagemap") was to force reads of /proc/pid/pagemap to be a
multiple of 8 bytes, but now it allows to read 0 bytes, which actually
puts some data to user's buffer.  According to POSIX, if count is zero,
read() should return zero and has no other results.

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Cc: Thomas Tuttle <ttuttle@google.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:09 -07:00
Martin Schwidefsky e1c805309d [S390] /proc/stat idle field for idle cpus
The cpu idle field in the output of /proc/stat is too small for cpus
that have been idle for more than a tick. Add the architecture hook
arch_idle_time that allows to add the not accounted idle time of a
sleeping cpu without waking the cpu.

The s390 implementation of arch_idle_time uses the already existing
s390_idle_data per_cpu variable to find the sleep time of a neighboring
idle cpu.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-23 13:58:17 +02:00
KOSAKI Motohiro 31b07093c4 proc: mounts_poll() make consistent to mdstat_poll
In recently sysfs_poll discussion, Neil Brown pointed out /proc/mounts
also should be fixed.

SUSv3 says "Regular files shall always poll TRUE for reading and
writing".  see
http://www.opengroup.org/onlinepubs/009695399/functions/poll.html

Then, mounts_poll()'s default should be "POLLIN | POLLRDNORM".  it mean
always readable.

In addition, event trigger should use "POLLERR | POLLPRI" instead
POLLERR.  it makes consistent to mdstat_poll() and sysfs_poll(). and,
select(2) can handle POLLPRI easily.


Reported-by: Neil Brown <neilb@suse.de>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16 16:17:10 -07:00
Nobuhiro Iwamatsu 4c967291fc nommu: fix typo vma->pg_off to vma->vm_pgoff
6260a4b052 ("/proc/pid/maps: don't show
pgoff of pure ANON VMAs" had a typo.

fs/proc/task_nommu.c:138: error: 'struct vm_area_struct' has no member named 'pg_off'
distcc[21484] ERROR: compile fs/proc/task_nommu.c on sprygo/32 failed

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-08 10:21:44 -07:00
KAMEZAWA Hiroyuki 6260a4b052 /proc/pid/maps: don't show pgoff of pure ANON VMAs
Recently, it's argued that what proc/pid/maps shows is ugly when a 32bit
binary runs on 64bit host.

/proc/pid/maps outputs vma's pgoff member but vma->pgoff is of no use
information is the vma is for ANON.  With this patch, /proc/pid/maps shows
just 0 if no file backing store.

[akpm@linux-foundation.org: coding-style fixes]
[kamezawa.hiroyu@jp.fujitsu.com: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mike Waychison <mikew@google.com>
Reported-by: Ying Han <yinghan@google.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:31:03 -07:00
Linus Torvalds 811158b147 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  trivial: Update my email address
  trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
  trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
  trivial: Fix misspelling of "Celsius".
  trivial: remove unused variable 'path' in alloc_file()
  trivial: fix a pdlfush -> pdflush typo in comment
  trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
  trivial: wusb: Storage class should be before const qualifier
  trivial: drivers/char/bsr.c: Storage class should be before const qualifier
  trivial: h8300: Storage class should be before const qualifier
  trivial: fix where cgroup documentation is not correctly referred to
  trivial: Give the right path in Documentation example
  trivial: MTD: remove EOL from MODULE_DESCRIPTION
  trivial: Fix typo in bio_split()'s documentation
  trivial: PWM: fix of #endif comment
  trivial: fix typos/grammar errors in Kconfig texts
  trivial: Fix misspelling of firmware
  trivial: cgroups: documentation typo and spelling corrections
  trivial: Update contact info for Jochen Hein
  trivial: fix typo "resgister" -> "register"
  ...
2009-04-03 15:24:35 -07:00
Linus Torvalds 8fe74cf053 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  Remove two unneeded exports and make two symbols static in fs/mpage.c
  Cleanup after commit 585d3bc06f
  Trim includes of fdtable.h
  Don't crap into descriptor table in binfmt_som
  Trim includes in binfmt_elf
  Don't mess with descriptor table in load_elf_binary()
  Get rid of indirect include of fs_struct.h
  New helper - current_umask()
  check_unsafe_exec() doesn't care about signal handlers sharing
  New locking/refcounting for fs_struct
  Take fs_struct handling to new file (fs/fs_struct.c)
  Get rid of bumping fs_struct refcount in pivot_root(2)
  Kill unsharing fs_struct in __set_personality()
2009-04-02 21:09:10 -07:00
David Howells 33e5d76979 nommu: fix a number of issues with the per-MM VMA patch
Fix a number of issues with the per-MM VMA patch:

 (1) Make mmap_pages_allocated an atomic_long_t, just in case this is used on
     a NOMMU system with more than 2G pages.  Makes no difference on a 32-bit
     system.

 (2) Report vma->vm_pgoff * PAGE_SIZE as a 64-bit value, not a 32-bit value,
     lest it overflow.

 (3) Move the allocation of the vm_area_struct slab back for fork.c.

 (4) Use KMEM_CACHE() for both vm_area_struct and vm_region slabs.

 (5) Use BUG_ON() rather than if () BUG().

 (6) Make the default validate_nommu_regions() a static inline rather than a
     #define.

 (7) Make free_page_series()'s objection to pages with a refcount != 1 more
     informative.

 (8) Adjust the __put_nommu_region() banner comment to indicate that the
     semaphore must be held for writing.

 (9) Limit the number of warnings about munmaps of non-mmapped regions.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:48 -07:00
Alexey Dobriyan 0f043a81eb proc tty: remove struct tty_operations::read_proc
struct tty_operations::proc_fops took it's place and there is one less
create_proc_read_entry() user now!

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:10 -07:00
Alexey Dobriyan ae149b6bec proc tty: add struct tty_operations::proc_fops
Used for gradual switch of TTY drivers from using ->read_proc which helps
with gradual switch from ->read_proc for the whole tree.

As side effect, fix possible race condition when ->data initialized after
PDE is hooked into proc tree.

->proc_fops takes precedence over ->read_proc.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:08 -07:00
Al Viro 5ad4e53bd5 Get rid of indirect include of fs_struct.h
Don't pull it in sched.h; very few files actually need it and those
can include directly.  sched.h itself only needs forward declaration
of struct fs_struct;

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:27 -04:00
Al Viro 498052bba5 New locking/refcounting for fs_struct
* all changes of current->fs are done under task_lock and write_lock of
  old fs->lock
* refcount is not atomic anymore (same protection)
* its decrements are done when removing reference from current; at the
  same time we decide whether to free it.
* put_fs_struct() is gone
* new field - ->in_exec.  Set by check_unsafe_exec() if we are trying to do
  execve() and only subthreads share fs_struct.  Cleared when finishing exec
  (success and failure alike).  Makes CLONE_FS fail with -EAGAIN if set.
* check_unsafe_exec() may fail with -EAGAIN if another execve() from subthread
  is in progress.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:26 -04:00
Alexey Dobriyan a9caa3de24 Revert "proc: revert /proc/uptime to ->read_proc hook"
This reverts commit 6c87df37dc.

proc files implemented through seq_file do pread(2) now.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:58 +04:00
Alexey Dobriyan 99b7623380 proc 2/2: remove struct proc_dir_entry::owner
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.

We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.

But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.

->read_proc/->write_proc were just fixed to not require ->owner for
protection.

rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.

Removing ->owner will also make PDE smaller.

So, let's nuke it.

Kudos to Jeff Layton for reminding about this, let's say, oversight.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:44 +04:00
Alexey Dobriyan 3dec7f59c3 proc 1/2: do PDE usecounting even for ->read_proc, ->write_proc
struct proc_dir_entry::owner is going to be removed. Now it's only necessary
to protect PDEs which are using ->read_proc, ->write_proc hooks.

However, ->owner assignments are racy and make it very easy for someone to switch
->owner on live PDE (as some subsystems do) without fixing refcounts and so on.

http://bugzilla.kernel.org/show_bug.cgi?id=12454

So, ->owner is on death row.

Proxy file operations exist already (proc_file_operations), just bump usecount
when necessary.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:27 +04:00
Milind Arun Choudhary 09729a9919 proc: fix sparse warnings in pagemap_read()
fs/proc/task_mmu.c:696:12: warning: cast removes address space of expression
fs/proc/task_mmu.c:696:9: warning: incorrect type in assignment (different address spaces)
fs/proc/task_mmu.c:696:9:    expected unsigned long long [noderef] [usertype] <asn:1>*out
fs/proc/task_mmu.c:696:9:    got unsigned long long [usertype] *<noident>
fs/proc/task_mmu.c:697:12: warning: cast removes address space of expression
fs/proc/task_mmu.c:697:9: warning: incorrect type in assignment (different address spaces)
fs/proc/task_mmu.c:697:9:    expected unsigned long long [noderef] [usertype] <asn:1>*end
fs/proc/task_mmu.c:697:9:    got unsigned long long [usertype] *<noident>
fs/proc/task_mmu.c:723:12: warning: cast removes address space of expression
fs/proc/task_mmu.c:723:26: error: subtraction of different types can't work (different address spaces)
fs/proc/task_mmu.c:725:24: error: subtraction of different types can't work (different address spaces)

Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:14:22 +04:00
Randy Dunlap 1681bc30f2 proc: move fs/proc/inode-alloc.txt comment into a source file
so that people will realize that it exists and can update it as needed.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-03-31 01:13:12 +04:00
Uwe Kleine-Koenig 973c32bebf trivial: fix typo "kernal" -> "kernel"
Signed-off-by: Uwe Kleine-Koenig <Uwe.Kleine-Koenig@digi.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-03-30 15:21:57 +02:00
Hugh Dickins 7c2c7d9930 fix setuid sometimes wouldn't
check_unsafe_exec() also notes whether the fs_struct is being
shared by more threads than will get killed by the exec, and if so
sets LSM_UNSAFE_SHARE to make bprm_set_creds() careful about euid.
But /proc/<pid>/cwd and /proc/<pid>/root lookups make transient
use of get_fs_struct(), which also raises that sharing count.

This might occasionally cause a setuid program not to change euid,
in the same way as happened with files->count (check_unsafe_exec
also looks at sighand->count, but /proc doesn't raise that one).

We'd prefer exec not to unshare fs_struct: so fix this in procfs,
replacing get_fs_struct() by get_fs_path(), which does path_get
while still holding task_lock, instead of raising fs->count.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
___

 fs/proc/base.c |   50 +++++++++++++++--------------------------------
 1 file changed, 16 insertions(+), 34 deletions(-)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-28 17:30:00 -07:00
Sukadev Bhattiprolu a3ec947c85 vfs: simple_set_mnt() should return void
simple_set_mnt() is defined as returning 'int' but always returns 0.
Callers assume simple_set_mnt() never fails and don't properly cleanup if
it were to _ever_ fail.  For instance, get_sb_single() and get_sb_nodev()
should:

        up_write(sb->s_unmount);
        deactivate_super(sb);

if simple_set_mnt() fails.

Since simple_set_mnt() never fails, would be cleaner if it did not
return anything.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27 14:44:03 -04:00
Al Viro d72f71eb0e constify dentry_operations: procfs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27 14:44:01 -04:00
Linus Torvalds ee568b25ee Avoid 64-bit "switch()" statements on 32-bit architectures
Commit ee6f779b9e ("filp->f_pos not
correctly updated in proc_task_readdir") changed the proc code to use
filp->f_pos directly, rather than through a temporary variable.  In the
process, that caused the operations to be done on the full 64 bits, even
though the offset is never that big.

That's all fine and dandy per se, but for some unfathomable reason gcc
generates absolutely horrid code when using 64-bit values in switch()
statements.  To the point of actually calling out to gcc helper
functions like __cmpdi2 rather than just doing the trivial comparisons
directly the way gcc does for normal compares.  At which point we get
link failures, because we really don't want to support that kind of
crazy code.

Fix this by just casting the f_pos value to "unsigned long", which
is plenty big enough for /proc, and avoids the gcc code generation issue.

Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Zhang Le <r0bertz@gentoo.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 10:02:35 -07:00
Zhang Le ee6f779b9e filp->f_pos not correctly updated in proc_task_readdir
filp->f_pos only get updated at the end of the function. Thus d_off of those
dirents who are in the middle will be 0, and this will cause a problem in
glibc's readdir implementation, specifically endless loop. Because when overflow
occurs, f_pos will be set to next dirent to read, however it will be 0, unless
the next one is the last one. So it will start over again and again.

There is a sample program in man 2 gendents. This is the output of the program
running on a multithread program's task dir before this patch is applied:

  $ ./a.out /proc/3807/task
  --------------- nread=128 ---------------
  i-node#  file type  d_reclen  d_off   d_name
    506442  directory    16          1  .
    506441  directory    16          0  ..
    506443  directory    16          0  3807
    506444  directory    16          0  3809
    506445  directory    16          0  3812
    506446  directory    16          0  3861
    506447  directory    16          0  3862
    506448  directory    16          8  3863

This is the output after this patch is applied

  $ ./a.out /proc/3807/task
  --------------- nread=128 ---------------
  i-node#  file type  d_reclen  d_off   d_name
    506442  directory    16          1  .
    506441  directory    16          2  ..
    506443  directory    16          3  3807
    506444  directory    16          4  3809
    506445  directory    16          5  3812
    506446  directory    16          6  3861
    506447  directory    16          7  3862
    506448  directory    16          8  3863

Signed-off-by: Zhang Le <r0bertz@gentoo.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-16 07:51:33 -07:00
Wu Fengguang ad3bdefe87 proc: fix kflags to uflags copying in /proc/kpageflags
Fix kpf_copy_bit(src,dst) to be kpf_copy_bit(dst,src) to match the
actual call patterns, e.g. kpf_copy_bit(kflags, KPF_LOCKED, PG_locked).

This misplacement of src/dst only affected reporting of PG_writeback,
PG_reclaim and PG_buddy. For others kflags==uflags so not affected.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-11 07:43:33 -07:00
Helge Bahmann e07a4b9217 proc: fix PG_locked reporting in /proc/kpageflags
Expr always evaluates to zero.

Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-02-24 21:17:58 +03:00
Krzysztof Sachanowicz cac711211a proc: proc_get_inode should de_put when inode already initialized
de_get is called before every proc_get_inode, but corresponding de_put is
called only when dropping last reference to an inode. This might cause
something like
remove_proc_entry: /proc/stats busy, count=14496
to be printed to the syslog.

The fix is to call de_put in case of an already initialized inode in
proc_get_inode.

Signed-off-by: Krzysztof Sachanowicz <analyzer1@gmail.com>
Tested-by: Marcin Pilipczuk <marcin.pilipczuk@gmail.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-23 18:25:32 -08:00
Linus Torvalds c40f6f8bbc Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-nommu
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-nommu:
  NOMMU: Support XIP on initramfs
  NOMMU: Teach kobjsize() about VMA regions.
  FLAT: Don't attempt to expand the userspace stack to fill the space allocated
  FDPIC: Don't attempt to expand the userspace stack to fill the space allocated
  NOMMU: Improve procfs output using per-MM VMAs
  NOMMU: Make mmap allocation page trimming behaviour configurable.
  NOMMU: Make VMAs per MM as for MMU-mode linux
  NOMMU: Delete askedalloc and realalloc variables
  NOMMU: Rename ARM's struct vm_region
  NOMMU: Fix cleanup handling in ramfs_nommu_get_umapped_area()
2009-01-09 14:00:58 -08:00
Magnus Damm 921d58c0e6 vmcore: remove saved_max_pfn check
Remove the saved_max_pfn check from the /proc/vmcore function
read_from_oldmem().  No need to verify, we should be able to just trust
that "elfcorehdr=" is correctly passed to the crash kernel on the kernel
command line like we do with other parameters.

The read_from_oldmem() function in fs/proc/vmcore.c is quite similar to
read_from_oldmem() in drivers/char/mem.c, but only in the latter it makes
sense to use saved_max_pfn.  For oldmem it is used to determine when to
stop reading.  For vmcore we already have the elf header info pointing out
the physical memory regions, no need to pass the end-of- old-memory twice.

Removing the saved_max_pfn check from vmcore makes it possible for
architectures to skip oldmem but still support crash dump through vmcore -
without the need for the old saved_max_pfn cruft.

Architectures that want to play safe can do the saved_max_pfn check in
copy_oldmem_page().  Not sure why anyone would want to do that, but that's
even safer than today - the saved_max_pfn check in vmcore removed by this
patch only checks the first page.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Simon Horman <horms@verge.net.au>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-08 08:31:14 -08:00
David Howells 38f714795b NOMMU: Improve procfs output using per-MM VMAs
Improve procfs output using per-MM VMAs for process memory accounting.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
2009-01-08 12:04:47 +00:00
David Howells 8feae13110 NOMMU: Make VMAs per MM as for MMU-mode linux
Make VMAs per mm_struct as for MMU-mode linux.  This solves two problems:

 (1) In SYSV SHM where nattch for a segment does not reflect the number of
     shmat's (and forks) done.

 (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an
     exec'ing process when VM_EXECUTABLE is specified, regardless of the fact
     that a VMA might be shared and already have its vm_mm assigned to another
     process or a dead process.

A new struct (vm_region) is introduced to track a mapped region and to remember
the circumstances under which it may be shared and the vm_list_struct structure
is discarded as it's no longer required.

This patch makes the following additional changes:

 (1) Regions are now allocated with alloc_pages() rather than kmalloc() and
     with no recourse to __GFP_COMP, so the pages are not composite.  Instead,
     each page has a reference on it held by the region.  Anything else that is
     interested in such a page will have to get a reference on it to retain it.
     When the pages are released due to unmapping, each page is passed to
     put_page() and will be freed when the page usage count reaches zero.

 (2) Excess pages are trimmed after an allocation as the allocation must be
     made as a power-of-2 quantity of pages.

 (3) VMAs are added to the parent MM's R/B tree and mmap lists.  As an MM may
     end up with overlapping VMAs within the tree, the VMA struct address is
     appended to the sort key.

 (4) Non-anonymous VMAs are now added to the backing inode's prio list.

 (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of
     the backing region.  The VMA and region structs will be split if
     necessary.

 (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory
     segment instead of all the attachments at that addresss.  Multiple
     shmat()'s return the same address under NOMMU-mode instead of different
     virtual addresses as under MMU-mode.

 (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode.

 (8) /proc/maps is now the global list of mapped regions, and may list bits
     that aren't actually mapped anywhere.

 (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount
     of RAM currently allocated by mmap to hold mappable regions that can't be
     mapped directly.  These are copies of the backing device or file if not
     anonymous.

These changes make NOMMU mode more similar to MMU mode.  The downside is that
NOMMU mode requires some extra memory to track things over NOMMU without this
patch (VMAs are no longer shared, and there are now region structs).

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
2009-01-08 12:04:47 +00:00
Linus Torvalds a0c9f240a9 Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc
* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc:
  proc: remove write-only variable in proc_pident_lookup()
  proc: fix sparse warning
  proc: add /proc/*/stack
  proc: remove '##' usage
  proc: remove useless WARN_ONs
  proc: stop using BKL
2009-01-07 12:01:06 -08:00
Linus Torvalds 57c44c5f6f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits)
  trivial: chack -> check typo fix in main Makefile
  trivial: Add a space (and a comma) to a printk in 8250 driver
  trivial: Fix misspelling of "firmware" in docs for ncr53c8xx/sym53c8xx
  trivial: Fix misspelling of "firmware" in powerpc Makefile
  trivial: Fix misspelling of "firmware" in usb.c
  trivial: Fix misspelling of "firmware" in qla1280.c
  trivial: Fix misspelling of "firmware" in a100u2w.c
  trivial: Fix misspelling of "firmware" in megaraid.c
  trivial: Fix misspelling of "firmware" in ql4_mbx.c
  trivial: Fix misspelling of "firmware" in acpi_memhotplug.c
  trivial: Fix misspelling of "firmware" in ipw2100.c
  trivial: Fix misspelling of "firmware" in atmel.c
  trivial: Fix misspelled firmware in Kconfig
  trivial: fix an -> a typos in documentation and comments
  trivial: fix then -> than typos in comments and documentation
  trivial: update Jesper Juhl CREDITS entry with new email
  trivial: fix singal -> signal typo
  trivial: Fix incorrect use of "loose" in event.c
  trivial: printk: fix indentation of new_text_line declaration
  trivial: rtc-stk17ta8: fix sparse warning
  ...
2009-01-07 11:31:52 -08:00
Mel Gorman 3340289ddf mm: report the MMU pagesize in /proc/pid/smaps
The KernelPageSize entry in /proc/pid/smaps is the pagesize used by the
kernel to back a VMA.  This matches the size used by the MMU in the
majority of cases.  However, one counter-example occurs on PPC64 kernels
whereby a kernel using 64K as a base pagesize may still use 4K pages for
the MMU on older processor.  To distinguish, this patch reports
MMUPageSize as the pagesize used by the MMU in /proc/pid/smaps.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: "KOSAKI Motohiro" <kosaki.motohiro@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:58:58 -08:00
Mel Gorman 08fba69986 mm: report the pagesize backing a VMA in /proc/pid/smaps
It is useful to verify a hugepage-aware application is using the expected
pagesizes for its memory regions. This patch creates an entry called
KernelPageSize in /proc/pid/smaps that is the size of page used by the
kernel to back a VMA. The entry is not called PageSize as it is possible
the MMU uses a different size. This extension should not break any sensible
parser that skips lines containing unrecognised information.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: "KOSAKI Motohiro" <kosaki.motohiro@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:58:58 -08:00
Frederik Schwarzer 025dfdafe7 trivial: fix then -> than typos in comments and documentation
- (better, more, bigger ...) then -> (...) than

Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-06 11:28:06 +01:00
Al Viro 56ff5efad9 zero i_uid/i_gid on inode allocation
... and don't bother in callers.  Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-05 11:54:28 -05:00
WANG Cong 230e40fbda proc: remove write-only variable in proc_pident_lookup()
Signed-off-by: WANG Cong <wangcong@zeuux.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-01-05 12:27:45 +03:00
Hannes Eder dfe6b7d940 proc: fix sparse warning
fs/proc/base.c:312:4: warning: do-while statement is not a compound statement

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-01-05 12:27:45 +03:00
Ken Chen 2ec220e27f proc: add /proc/*/stack
/proc/*/stack adds the ability to query a task's stack trace. It is more
useful than /proc/*/wchan as it provides full stack trace instead of single
depth. Example output:

	$ cat /proc/self/stack
	[<c010a271>] save_stack_trace_tsk+0x17/0x35
	[<c01827b4>] proc_pid_stack+0x4a/0x76
	[<c018312d>] proc_single_show+0x4a/0x5e
	[<c016bdec>] seq_read+0xf3/0x29f
	[<c015a004>] vfs_read+0x6d/0x91
	[<c015a0c1>] sys_read+0x3b/0x60
	[<c0102eda>] syscall_call+0x7/0xb
	[<ffffffff>] 0xffffffff

[add save_stack_trace_tsk() on mips, ACK Ralf --adobriyan]
Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-01-05 12:27:44 +03:00