Every inode in /proc holds a reference to a struct task_struct. If a
directory or file is opened and remains open after the the task exits this
pinning continues. With 8K stacks on a 32bit machine the amount pinned per
file descriptor is about 10K.
Normally I would figure a reasonable per user process limit is about 100
processes. With 80 processes, with a 1000 file descriptors each I can trigger
the 00M killer on a 32bit kernel, because I have pinned about 800MB of useless
data.
This patch replaces the struct task_struct pointer with a pointer to a struct
task_ref which has a struct task_struct pointer. The so the pinning of dead
tasks does not happen.
The code now has to contend with the fact that the task may now exit at any
time. Which is a little but not muh more complicated.
With this change it takes about 1000 processes each opening up 1000 file
descriptors before I can trigger the OOM killer. Much better.
[mlp@google.com: task_mmu small fixes]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Paul Jackson <pj@sgi.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Albert Cahalan <acahalan@gmail.com>
Signed-off-by: Prasanna Meda <mlp@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently in /proc at several different places we define buffers to hold a
process id, or a file descriptor . In most of them we use either a hard coded
number or a different define. Modify them all to use PROC_NUMBUF, so the code
has a chance of being maintained.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Like the bug Oleg spotted in first_tid there was also a small off by one
error in first_tgid, when a seek was done on the /proc directory. This
fixes that and changes the code structure to make it a little more obvious
what is going on.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since we no longer need the tasklist_lock for get_task_struct the lookup
methods no longer need the tasklist_lock.
This just depends on my previous patch that makes get_task_struct() rcu
safe.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We don't need the tasklist_lock to safely iterate through processes
anymore.
This depends on my previous to task patches that make get_task_struct rcu
safe, and that make next_task() rcu safe. I haven't gotten
first_tid/next_tid yet only because next_thread is missing an
rcu_dereference.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There are a couple of problems this patch addresses.
- /proc/<tgid>/task currently does not work correctly if you stop reading
in the middle of a directory.
- /proc/ currently requires a full pass through the task list with
the tasklist lock held, to determine there are no more processes to read.
- The hand rolled integer to string conversion does not properly running
out of buffer space.
- We seem to be batching reading of pids from the tasklist without reason,
and complicating the logic of the code.
This patch addresses that by changing how tasks are processed. A
first_<task_type> function is built that handles restarts, and a
next_<task_type> function is built that just advances to the next task.
first_<task_type> when it detects a restart usually uses find_task_by_pid. If
that doesn't work because there has been a seek on the directory, or we have
already given a complete directory listing, it first checks the number tasks
of that type, and only if we are under that count does it walk through all of
the tasks to find the one we are interested in.
The code that fills in the directory is simpler because there is only a single
for loop.
The hand rolled integer to string conversion is replaced by snprintf which
should handle the the out of buffer case correctly.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
proc_lookup and task exiting are not synchronized, although some of the
previous code may have suggested that. Every time before we reuse a dentry
namei.c calls d_op->derevalidate which prevents us from reusing a stale dcache
entry. Unfortunately it does not prevent us from returning a stale dcache
entry. This race has been explicitly plugged in proc_pid_lookup but there is
nothing to confine it to just that proc lookup function.
So to prevent the race I call revalidate explictily in all of the proc lookup
functions after I call d_add, and report an error if the revalidate does not
succeed.
Years ago Al Viro did something similar but those changes got lost in the
churn.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
To keep the dcache from filling up with dead /proc entries we flush them on
process exit. However over the years that code has gotten hairy with a
dentry_pointer and a lock in task_struct and misdocumented as a correctness
feature.
I have rewritten this code to look and see if we have a corresponding entry in
the dcache and if so flush it on process exit. This removes the extra fields
in the task_struct and allows me to trivially handle the case of a
/proc/<tgid>/task/<pid> entry as well as the current /proc/<pid> entries.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
All of the functions for proc_maps_operations are already defined in
task_mmu.c so move the operations structure to keep the functionality
together.
Since task_nommu.c implements a dummy version of /proc/<pid>/maps give it a
simplified version of proc_maps_operations that it can modify to best suit its
needs.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use getattr to get an accurate link count when needed. This is cheaper and
more accurate than trying to derive it by walking the thread list of a
process.
Especially as it happens when needed stat instead of at readdir time.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Long ago and far away in 2.2 we started checking to ensure the files we
displayed in /proc were visible to the current process. It was an
unsophisticated time and no one was worried about functions full of FIXMES in
a stable kernel. As time passed the function became sacred and was enshrined
in the shrine of how things have always been. The fixes came in but only to
keep the function working no one really remembering or documenting why we did
things that way.
The intent and the functionality make a lot of sense. Don't let /proc be an
access point for files a process can see no other way. The implementation
however is completely wrong.
We are currently checking the root directories of the two processes, we are
not checking the actual file descriptors themselves.
We are strangely checking with a permission method instead of just when we use
the data.
This patch fixes the logic to actually check the file descriptors and make a
note that implementing a permission method for this part of /proc almost
certainly indicates a bug in the reasoning.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The inode operations only exist to support the proc_permission function.
Currently mem_read and mem_write have all the same permission checks as
ptrace. The fs check makes no sense in this context, and we can trivially get
around it by calling ptrace.
So simply the code by killing the strange weird case.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
First we can access every /proc/<tgid>/task/<pid> directory as /proc/<pid> so
proc_task_permission is not usefully limiting visibility.
Second having related filesystems information should have nothing to do with
process visibility. kill does not implement any checks like that.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The sole renaming use of proc_inode.type is to discover the file descriptor
number, so just store the file descriptor number and don't wory about
processing this field. This removes any /proc limits on the maximum number of
file descriptors, and clears the path to make the hard coded /proc inode
numbers go away.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently in /proc if the task is dumpable all of files are owned by the tasks
effective users. Otherwise the files are owned by root. Unless it is the
/proc/<tgid>/ or /proc/<tgid>/task/<pid> directory in that case we always make
the directory owned by the effective user.
However the special case for directories is pointless except as a way to read
the effective user, because the permissions on both of those directories are
world readable, and executable.
/proc/<tgid>/status provides a much better way to read a processes effecitve
userid, so it is silly to try to provide that on the directory.
So this patch simplifies the code by removing a pointless special case and
gets us one step closer to being able to remove the hard coded /proc inode
numbers.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The removed fields are already set by proc_alloc_inode. Initializing them in
proc_alloc_inode implies they need it for proper cleanup. At least ei->pde
was not set on all paths making it look like proc_alloc_inode was buggy. So
just remove the redundant assignments.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We already call everything except do_proc_readlink outside of the BKL in
proc_pid_followlink, and there appears to be nothing in do_proc_readlink that
needs any special protection.
So remove this leftover from one of the BKL cleanup efforts.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a /proc/<pid>/attr/keycreate entry that stores the appropriate context for
newly-created keys. Modify the selinux_key_alloc hook to make use of the new
entry. Update the flask headers to include a new "setkeycreate" permission
for processes. Update the flask headers to include a new "create" permission
for keys. Use the create permission to restrict which SIDs each task can
assign to newly-created keys. Add a new parameter to the security hook
"security_key_alloc" to indicate whether it is being invoked by the kernel, or
from userspace. If it is being invoked by the kernel, the security hook
should never fail. Update the documentation to reflect these changes.
Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.
The filesystem is then required to manually set the superblock and root dentry
pointers. For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).
The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.
This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing. In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.
The patch also makes the following changes:
(*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
pointer argument and return an integer, so most filesystems have to change
very little.
(*) If one of the convenience function is not used, then get_sb() should
normally call simple_set_mnt() to instantiate the vfsmount. This will
always return 0, and so can be tail-called from get_sb().
(*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
dcache upon superblock destruction rather than shrink_dcache_anon().
This is required because the superblock may now have multiple trees that
aren't actually bound to s_root, but that still need to be cleaned up. The
currently called functions assume that the whole tree is rooted at s_root,
and that anonymous dentries are not the roots of trees which results in
dentries being left unculled.
However, with the way NFS superblock sharing are currently set to be
implemented, these assumptions are violated: the root of the filesystem is
simply a dummy dentry and inode (the real inode for '/' may well be
inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
with child trees.
[*] Anonymous until discovered from another tree.
(*) The documentation has been adjusted, including the additional bit of
changing ext2_* into foo_* in the documentation.
[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There are places in the kernel where we look up files in fd tables and
access the file structure without holding refereces to the file. So, we
need special care to avoid the race between looking up files in the fd
table and tearing down of the file in another CPU. Otherwise, one might
see a NULL f_dentry or such torn down version of the file. This patch
fixes those special places where such a race may happen.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A couple of /proc/vmcore data structures overflow with 32bit systems having
memory more than 4G. This patch fixes those.
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
proc_check_chroot() does the check in a very unintuitive way (keeping a
copy of the argument, then modifying the argument), and has uncommented
sideeffects.
Signed-off-by: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make baby-simple the code for /proc/devices. Based on the proven design
for /proc/interrupts.
This also fixes the early-termination regression 2.6.16 introduced, as
demonstrated by:
# dd if=/proc/devices bs=1
Character devices:
1 mem
27+0 records in
27+0 records out
This should also work (but is untested) when /proc/devices >4096 bytes,
which I believe is what the original 2.6.16 rewrite fixed.
[akpm@osdl.org: cleanups, simplifications]
Signed-off-by: Joe Korty <joe.korty@ccur.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a conversion to make the various file_operations structs in fs/
const. Basically a regexp job, with a few manual fixups
The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mark the f_ops members of inodes as const, as well as fix the
ripple-through this causes by places that copy this f_ops and then "do
stuff" with it.
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Various dodgy firmware might give us nodes and/or properties in the device
tree with conflicting names. That's generally ok, except for when we export
the device tree via /proc, so check when we're creating the proc device tree
and munge names accordingly.
Tested on a faked device tree with kexec, would be good if someone with
actual bogus firmware could try it, but just for completeness.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove the it_real_value from /proc/*/stat, during 1.2.x was the last time it
returned useful data (as it was directly maintained by the scheduler), now
it's only a waste of time to calculate it. Return 0 instead.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It has been discovered that the remove_proc_entry has a race in the removing
of entries in the proc file system that are siblings. There's no protection
around the traversing and removing of elements that belong in the same
subdirectory.
This subdirectory list is protected in other areas by the BKL. So the BKL was
at first used to protect this area too, but unfortunately, remove_proc_entry
may be called with spinlocks held. The BKL may schedule, so this was not a
solution.
The final solution was to add a new global spin lock to protect this list,
called proc_subdir_lock. This lock now protects the list in
remove_proc_entry, and I also went around looking for other areas that this
list is modified and added this protection there too. Care must be taken
since these locations call several functions that may also schedule.
Since I don't see any location that these functions that modify the
subdirectory list are called by interrupts, the irqsave/restore versions of
the spin lock was _not_ used.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (103 commits)
SUNRPC,RPCSEC_GSS: spkm3--fix config dependencies
SUNRPC,RPCSEC_GSS: spkm3: import contexts using NID_cast5_cbc
LOCKD: Make nlmsvc_traverse_shares return void
LOCKD: nlmsvc_traverse_blocks return is unused
SUNRPC,RPCSEC_GSS: fix krb5 sequence numbers.
NFSv4: Dont list system.nfs4_acl for filesystems that don't support it.
SUNRPC,RPCSEC_GSS: remove unnecessary kmalloc of a checksum
SUNRPC: Ensure rpc_call_async() always calls tk_ops->rpc_release()
SUNRPC: Fix memory barriers for req->rq_received
NFS: Fix a race in nfs_sync_inode()
NFS: Clean up nfs_flush_list()
NFS: Fix a race with PG_private and nfs_release_page()
NFSv4: Ensure the callback daemon flushes signals
SUNRPC: Fix a 'Busy inodes' error in rpc_pipefs
NFS, NLM: Allow blocking locks to respect signals
NFS: Make nfs_fhget() return appropriate error values
NFSv4: Fix an oops in nfs4_fill_super
lockd: blocks should hold a reference to the nlm_file
NFSv4: SETCLIENTID_CONFIRM should handle NFS4ERR_DELAY/NFS4ERR_RESOURCE
NFSv4: Send the delegation stateid for SETATTR calls
...
Rewrap the overly long source code lines resulting from the previous
patch's addition of the slab cache flag SLAB_MEM_SPREAD. This patch
contains only formatting changes, and no function change.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mark file system inode and similar slab caches subject to SLAB_MEM_SPREAD
memory spreading.
If a slab cache is marked SLAB_MEM_SPREAD, then anytime that a task that's
in a cpuset with the 'memory_spread_slab' option enabled goes to allocate
from such a slab cache, the allocations are spread evenly over all the
memory nodes (task->mems_allowed) allowed to that task, instead of favoring
allocation on the node local to the current cpu.
The following inode and similar caches are marked SLAB_MEM_SPREAD:
file cache
==== =====
fs/adfs/super.c adfs_inode_cache
fs/affs/super.c affs_inode_cache
fs/befs/linuxvfs.c befs_inode_cache
fs/bfs/inode.c bfs_inode_cache
fs/block_dev.c bdev_cache
fs/cifs/cifsfs.c cifs_inode_cache
fs/coda/inode.c coda_inode_cache
fs/dquot.c dquot
fs/efs/super.c efs_inode_cache
fs/ext2/super.c ext2_inode_cache
fs/ext2/xattr.c (fs/mbcache.c) ext2_xattr
fs/ext3/super.c ext3_inode_cache
fs/ext3/xattr.c (fs/mbcache.c) ext3_xattr
fs/fat/cache.c fat_cache
fs/fat/inode.c fat_inode_cache
fs/freevxfs/vxfs_super.c vxfs_inode
fs/hpfs/super.c hpfs_inode_cache
fs/isofs/inode.c isofs_inode_cache
fs/jffs/inode-v23.c jffs_fm
fs/jffs2/super.c jffs2_i
fs/jfs/super.c jfs_ip
fs/minix/inode.c minix_inode_cache
fs/ncpfs/inode.c ncp_inode_cache
fs/nfs/direct.c nfs_direct_cache
fs/nfs/inode.c nfs_inode_cache
fs/ntfs/super.c ntfs_big_inode_cache_name
fs/ntfs/super.c ntfs_inode_cache
fs/ocfs2/dlm/dlmfs.c dlmfs_inode_cache
fs/ocfs2/super.c ocfs2_inode_cache
fs/proc/inode.c proc_inode_cache
fs/qnx4/inode.c qnx4_inode_cache
fs/reiserfs/super.c reiser_inode_cache
fs/romfs/inode.c romfs_inode_cache
fs/smbfs/inode.c smb_inode_cache
fs/sysv/inode.c sysv_inode_cache
fs/udf/super.c udf_inode_cache
fs/ufs/super.c ufs_inode_cache
net/socket.c sock_inode_cache
net/sunrpc/rpc_pipe.c rpc_inode_cache
The choice of which slab caches to so mark was quite simple. I marked
those already marked SLAB_RECLAIM_ACCOUNT, except for fs/xfs, dentry_cache,
inode_cache, and buffer_head, which were marked in a previous patch. Even
though SLAB_RECLAIM_ACCOUNT is for a different purpose, it marks the same
potentially large file system i/o related slab caches as we need for memory
spreading.
Given that the rule now becomes "wherever you would have used a
SLAB_RECLAIM_ACCOUNT slab cache flag before (usually the inode cache), use
the SLAB_MEM_SPREAD flag too", this should be easy enough to maintain.
Future file system writers will just copy one of the existing file system
slab cache setups and tend to get it right without thinking.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix a duplicate block device line printed after the "Block device" header
in /proc/devices.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create a new file under /proc/self, called mountstats, where mounted file
systems can export information (configuration options, performance counters,
and so on). Use a mechanism similar to /proc/mounts and s_ops->show_options.
This mechanism does not violate namespace security, and is safe to use while
other processes are unmounting file systems.
Thanks to Mike Waychison for his review and comments.
Test-plan:
Test concurrent mount/unmount operations while cat'ing /proc/self/mountstats.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The point of the smaps "shared" is to count the number of pages that are
mapped by more than one process, according to Mauricio Lin. However, smaps
uses page_count for this, so it will return a false positive for every page
that is mapped by just that one process, which is also in pagecache or
swapcache. There are false positive situations for anonymous pages not in
swapcache as well: - page reclaim, migration - get_user_pages (eg.
direct-io, ptrace)
Use page_mapcount instead, to count the number of mappings to the page.
Use vm_normal_page so that weird things like /dev/mem aren't counted either.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1) it should use nr_processes(), not nr_threads; otherwise we are getting
very confused find(1) and friends, among other things.
2) better do that at stat() time than at every damn lookup in procfs root.
Patch had been sitting in FC4 kernels for many months now...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Don't compute and display the per-irq sums on ia64 either, too much
overhead for mostly useless figures.
Cc: Olaf Hering <olh@suse.de>
Acked-by: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A Christoph suggested that the /proc/devices file be converted to use the
seq_file interface. This patch does that.
I've obxerved one or two installation that had sufficiently large sans that
they overran the 4k limit on /proc/devices.
Signed-off-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add support to the proc_device_tree file for removing
and updating properties. Remove just removes the
proc file, update changes the data pointer within
the proc file. The remainder of the device-tree
changes occur elsewhere.
Signed-off-by: Dave Boutcher <sleddog@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
fs: Use <linux/capability.h> where capable() is used.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o fs/proc/vmcore.c compilation gives warnings on ppc64. The reason being
that u64 is defined as unsigned long hence u64* is not same as loff_t*
and compiler cribs.
o Changed the parameter type to u64* instead of loff_t* to resolve the
conflict.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Moving the crash_dump.c file to arch dependent part as kmap_atomic_pfn is
specific to i386 and highmem may not exist in other archs.
- Use ioremap for x86_64 to map the previous kernel memory.
- In copy_oldmem_page(), we now directly copy to the user/kernel buffer and
avoid the unneccesary copy to a kmalloc'd page.
Signed-off-by: Rachita Kothiyal <rachita@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Function prototypes belong into header files.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
First discussed at http://marc.theaimsgroup.com/?t=113149255100001&r=1&w=2
- Use the check_range() in mempolicy.c to gather statistics.
- Improve the numa_maps code in general and fix some comments.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Sanitize some s390 Kconfig options. We have ARCH_S390, ARCH_S390X,
ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT. Replace these 6 options by
S390, 64BIT and COMPAT.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The old /proc interfaces were never updated to use loff_t, and are just
generally broken. Now, we should be using the seq_file interface for
all of the proc files, but converting the legacy functions is more work
than most people care for and has little upside..
But at least we can make the non-LFS rules explicit, rather than just
insanely wrapping the offset or something.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This replaces the (in my opinion horrible) VM_UNMAPPED logic with very
explicit support for a "remapped page range" aka VM_PFNMAP. It allows a
VM area to contain an arbitrary range of page table entries that the VM
never touches, and never considers to be normal pages.
Any user of "remap_pfn_range()" automatically gets this new
functionality, and doesn't even have to mark the pages reserved or
indeed mark them any other way. It just works. As a side effect, doing
mmap() on /dev/mem works for arbitrary ranges.
Sparc update from David in the next commit.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the ability to the SMU driver to recover missing
calibration partitions from the SMU chip itself. It also adds some
dynamic mecanism to /proc/device-tree so that new properties are visible
to userland.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch fixes incorrect error path in proc_get_inode(), when module
can't be get due to being unloaded. When try_module_get() fails, this
function puts de(!) and still returns inode with non-getted de.
There are still unresolved known bugs in proc yet to be fixed:
- proc_dir_entry tree is managed without any serialization
- create_proc_entry() doesn't setup de->owner anyhow,
so setting it later manually is inatomic.
- looks like almost all modules do not care whether
it's de->owner is set...
Signed-Off-By: Denis Lunev <den@sw.ru>
Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead
in a memory location that is not anymore used at call_rcu(&f->f_rcuhead,
file_free_rcu) time, to reduce the size of this critical kernel object.
The trick I used is to move f_rcuhead and f_list in an union called f_u
The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list
becomes f_u.f_list
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Final step in pushing down common core's page_table_lock. follow_page no
longer wants caller to hold page_table_lock, uses pte_offset_map_lock itself;
and so no page_table_lock is taken in get_user_pages itself.
But get_user_pages (and get_futex_key) do then need follow_page to pin the
page for them: take Daniel's suggestion of bitflags to follow_page.
Need one for WRITE, another for TOUCH (it was the accessed flag before:
vanished along with check_user_page_readable, but surely get_numa_maps is
wrong to mark every page it finds as accessed), another for GET.
And another, ANON to dispose of untouched_anonymous_page: it seems silly for
that to descend a second time, let follow_page observe if there was no page
table and return ZERO_PAGE if so. Fix minor bug in that: check VM_LOCKED -
make_pages_present ought to make readonly anonymous present.
Give get_numa_maps a cond_resched while we're there.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert those common loops using page_table_lock on the outside and
pte_offset_map within to use just pte_offset_map_lock within instead.
These all hold mmap_sem (some exclusively, some not), so at no level can a
page table be whipped away from beneath them. But whereas pte_alloc loops
tested with the "atomic" pmd_present, these loops are testing with pmd_none,
which on i386 PAE tests both lower and upper halves.
That's now unsafe, so add a cast into pmd_none to test only the vital lower
half: we lose a little sensitivity to a corrupt middle directory, but not
enough to worry about. It appears that i386 and UML were the only
architectures vulnerable in this way, and pgd and pud no problem.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
update_mem_hiwater has attracted various criticisms, in particular from those
concerned with mm scalability. Originally it was called whenever rss or
total_vm got raised. Then many of those callsites were replaced by a timer
tick call from account_system_time. Now Frank van Maarseveen reports that to
be found inadequate. How about this? Works for Frank.
Replace update_mem_hiwater, a poor combination of two unrelated ops, by macros
update_hiwater_rss and update_hiwater_vm. Don't attempt to keep
mm->hiwater_rss up to date at timer tick, nor every time we raise rss (usually
by 1): those are hot paths. Do the opposite, update only when about to lower
rss (usually by many), or just before final accounting in do_exit. Handle
mm->hiwater_vm in the same way, though it's much less of an issue. Demand
that whoever collects these hiwater statistics do the work of taking the
maximum with rss or total_vm.
And there has been no collector of these hiwater statistics in the tree. The
new convention needs an example, so match Frank's usage by adding a VmPeak
line above VmSize to /proc/<pid>/status, and also a VmHWM line above VmRSS
(High-Water-Mark or High-Water-Memory).
There was a particular anomaly during mremap move, that hiwater_vm might be
captured too high. A fleeting such anomaly remains, but it's quickly
corrected now, whereas before it would stick.
What locking? None: if the app is racy then these statistics will be racy,
it's not worth any overhead to make them exact. But whenever it suits,
hiwater_vm is updated under exclusive mmap_sem, and hiwater_rss under
page_table_lock (for now) or with preemption disabled (later on): without
going to any trouble, minimize the time between reading current values and
updating, to minimize those occasions when a racing thread bumps a count up
and back down in between.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I was lazy when we added anon_rss, and chose to change as few places as
possible. So currently each anonymous page has to be counted twice, in rss
and in anon_rss. Which won't be so good if those are atomic counts in some
configurations.
Change that around: keep file_rss and anon_rss separately, and add them
together (with get_mm_rss macro) when the total is needed - reading two
atomics is much cheaper than updating two atomics. And update anon_rss
upfront, typically in memory.c, not tucked away in page_add_anon_rmap.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The NUMA policy code predated nodemask_t so it used open coded bitmaps.
Convert everything to nodemask_t. Big patch, but shouldn't have any actual
behaviour changes (except I removed one unnecessary check against
node_online_map and one unnecessary BUG_ON)
Signed-off-by: "Andi Kleen" <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently you do not get all the map entries on nommu systems because the
start function doesn't index into the list using the value of "pos".
Signed-off-by: David McCullough <davidm@snapgear.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
"proc_smaps_operations" is not defined in case of "CONFIG_MMU=n".
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This creates the directory structure under arch/powerpc and a bunch
of Kconfig files. It does a first-cut merge of arch/powerpc/mm,
arch/powerpc/lib and arch/powerpc/platforms/powermac. This is enough
to build a 32-bit powermac kernel with ARCH=powerpc.
For now we are getting some unmerged files from arch/ppc/kernel and
arch/ppc/syslib, or arch/ppc64/kernel. This makes some minor changes
to files in those directories and files outside arch/powerpc.
The boot directory is still not merged. That's going to be interesting.
Signed-off-by: Paul Mackerras <paulus@samba.org>
fs/proc/base.c: In function `proc_task_root_link':
fs/proc/base.c:364: warning: ISO C90 forbids mixed declarations and code
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When the main thread of a thread group has done pthread_exit() and died,
the other threads are still happily running, but will not be visible
under /proc because their leader is no longer accessible.
This fixes the access control so that we can see the sub-threads again.
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With the new fdtable locking rules, you have to protect fdtable with either
->file_lock or rcu_read_lock/unlock(). There are some places where we
aren't doing either. This patch fixes those places.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With the use of RCU in files structure, the look-up of files using fds can now
be lock-free. The lookup is protected by rcu_read_lock()/rcu_read_unlock().
This patch changes the readers to use lock-free lookup.
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Ravikiran Thirumalai <kiran_th@gmail.com>
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In order for the RCU to work, the file table array, sets and their sizes must
be updated atomically. Instead of ensuring this through too many memory
barriers, we put the arrays and their sizes in a separate structure. This
patch takes the first step of putting the file table elements in a separate
structure fdtable that is embedded withing files_struct. It also changes all
the users to refer to the file table using files_fdtable() macro. Subsequent
applciation of RCU becomes easier after this.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Update the file systems in fs/ implementing a delete_inode() callback to
call truncate_inode_pages(). One implementation note: In developing this
patch I put the calls to truncate_inode_pages() at the very top of those
filesystems delete_inode() callbacks in order to retain the previous
behavior. I'm guessing that some of those could probably be optimized.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Extract common code used by ptrace_attach() and may_ptrace_attach()
into a separate function.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes wrongly placed elements in the pid_directory_inos
enum. Also add comment so this mistake is not repeated.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch cleans up proc_cwd_link() and proc_root_link() by factoring
out common code into get_fs_struct().
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes bug titled "sunrpc as module and bad proc/sys link count"
reported by Jiri Slaby.
The problem was, that only proc_dir_entry->nlink was updated and the
corresponding inode->i_nlink was not. The fix is to implement the
inode->getattr() method, and update i_nlink (if necessary).
A quick audit of proc code shows that no other attribute changes after
creation.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a "smaps" entry to /proc/pid: show howmuch memory is resident in each
mapping.
People that want to perform a memory consumption analysing can use it
mainly if someone needs to figure out which libraries can be reduced for
embedded systems. So the new features are the physical size of shared and
clean [or dirty]; private and clean [or dirty].
Take a look the example below:
# cat /proc/4576/smaps
08048000-080dc000 r-xp /bin/bash
Size: 592 KB
Rss: 500 KB
Shared_Clean: 500 KB
Shared_Dirty: 0 KB
Private_Clean: 0 KB
Private_Dirty: 0 KB
080dc000-080e2000 rw-p /bin/bash
Size: 24 KB
Rss: 24 KB
Shared_Clean: 0 KB
Shared_Dirty: 0 KB
Private_Clean: 0 KB
Private_Dirty: 24 KB
080e2000-08116000 rw-p
Size: 208 KB
Rss: 208 KB
Shared_Clean: 0 KB
Shared_Dirty: 0 KB
Private_Clean: 0 KB
Private_Dirty: 208 KB
b7e2b000-b7e34000 r-xp /lib/tls/libnss_files-2.3.2.so
Size: 36 KB
Rss: 12 KB
Shared_Clean: 12 KB
Shared_Dirty: 0 KB
Private_Clean: 0 KB
Private_Dirty: 0 KB
...
(Includes a cleanup from "Richard Purdie" <rpurdie@rpsys.net>)
From: Torsten Foertsch <torsten.foertsch@gmx.net>
show_smap calls first show_map and then prints its additional information to
the seq_file. show_map checks if all it has to print fits into the buffer and
if yes marks the current vma as written. While that is correct for show_map
it is not for show_smap. Here the vma should be marked as written only after
the additional information is also written.
The attached patch cures the problem. It moves the functionality of the
show_map function to a new function show_map_internal that is called with an
additional struct mem_size_stats* argument. Then show_map calls
show_map_internal with NULL as struct mem_size_stats* whereas show_smap calls
it with a real pointer. Now the final
if (m->count < m->size) /* vma is copied successfully */
m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
is done only if the whole entry fits into the buffer.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch was recently discussed on linux-mm:
http://marc.theaimsgroup.com/?t=112085728500002&r=1&w=2
I inherited a large code base from Ray for page migration. There was a
small patch in there that I find to be very useful since it allows the
display of the locality of the pages in use by a process. I reworked that
patch and came up with a /proc/<pid>/numa_maps that gives more information
about the vma's of a process. numa_maps is indexes by the start address
found in /proc/<pid>/maps. F.e. with this patch you can see the page use
of the "getty" process:
margin:/proc/12008 # cat maps
00000000-00004000 r--p 00000000 00:00 0
2000000000000000-200000000002c000 r-xp 00000000 08:04 516 /lib/ld-2.3.3.so
2000000000038000-2000000000040000 rw-p 00028000 08:04 516 /lib/ld-2.3.3.so
2000000000040000-2000000000044000 rw-p 2000000000040000 00:00 0
2000000000058000-2000000000260000 r-xp 00000000 08:04 54707842 /lib/tls/libc.so.6.1
2000000000260000-2000000000268000 ---p 00208000 08:04 54707842 /lib/tls/libc.so.6.1
2000000000268000-2000000000274000 rw-p 00200000 08:04 54707842 /lib/tls/libc.so.6.1
2000000000274000-2000000000280000 rw-p 2000000000274000 00:00 0
2000000000280000-20000000002b4000 r--p 00000000 08:04 9126923 /usr/lib/locale/en_US.utf8/LC_CTYPE
2000000000300000-2000000000308000 r--s 00000000 08:04 60071467 /usr/lib/gconv/gconv-modules.cache
2000000000318000-2000000000328000 rw-p 2000000000318000 00:00 0
4000000000000000-4000000000008000 r-xp 00000000 08:04 29576399 /sbin/mingetty
6000000000004000-6000000000008000 rw-p 00004000 08:04 29576399 /sbin/mingetty
6000000000008000-600000000002c000 rw-p 6000000000008000 00:00 0 [heap]
60000fff7fffc000-60000fff80000000 rw-p 60000fff7fffc000 00:00 0
60000ffffff44000-60000ffffff98000 rw-p 60000ffffff44000 00:00 0 [stack]
a000000000000000-a000000000020000 ---p 00000000 00:00 0 [vdso]
cat numa_maps
2000000000000000 default MaxRef=43 Pages=11 Mapped=11 N0=4 N1=3 N2=2 N3=2
2000000000038000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2
2000000000040000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1
2000000000058000 default MaxRef=43 Pages=61 Mapped=61 N0=14 N1=15 N2=16 N3=16
2000000000268000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2
2000000000274000 default MaxRef=1 Pages=3 Mapped=3 Anon=3 N0=3
2000000000280000 default MaxRef=8 Pages=3 Mapped=3 N0=3
2000000000300000 default MaxRef=8 Pages=2 Mapped=2 N0=2
2000000000318000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N2=1
4000000000000000 default MaxRef=6 Pages=2 Mapped=2 N1=2
6000000000004000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1
6000000000008000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1
60000fff7fffc000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1
60000ffffff44000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1
getty uses ld.so. The first vma is the code segment which is used by 43
other processes and the pages are evenly distributed over the 4 nodes.
The second vma is the process specific data portion for ld.so. This is
only one page.
The display format is:
<startaddress> Links to information in /proc/<pid>/map
<memory policy> This can be "default" "interleave={}", "prefer=<node>" or "bind={<zones>}"
MaxRef= <maximum reference to a page in this vma>
Pages= <Nr of pages in use>
Mapped= <Nr of pages with mapcount >
Anon= <nr of anonymous pages>
Nx= <Nr of pages on Node x>
The content of the proc-file is self-evident. If this would be tied into
the sparsemem system then the contents of this file would not be too
useful.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
o Adds support for parsing core ELF32 headers.
o I am expecting ELF32 support to go away down the line. This patch has been
introduced for testing purposes as gdb can not parse ELF64 headers for
i386. When a decent user space solution is available, ELF32 support
can go away.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
From: "Vivek Goyal" <vgoyal@in.ibm.com>
o Support for /proc/vmcore interface. This interface exports elf core image
either in ELF32 or ELF64 format, depending on the format in which elf headers
have been stored by crashed kernel.
o Added support for CONFIG_VMCORE config option.
o Removed the dependency on /proc/kcore.
From: "Eric W. Biederman" <ebiederm@xmission.com>
This patch has been refactored to more closely match the prevailing style in
the affected files. And to clearly indicate the dependency between
/proc/kcore and proc/vmcore.c
From: Hariprasad Nellitheertha <hari@in.ibm.com>
This patch contains the code that provides an ELF format interface to the
previous kernel's memory post kexec reboot.
Signed off by Hariprasad Nellitheertha <hari@in.ibm.com>
Signed-off-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a new `suid_dumpable' sysctl:
This value can be used to query and set the core dump mode for setuid
or otherwise protected/tainted binaries. The modes are
0 - (default) - traditional behaviour. Any process which has changed
privilege levels or is execute only will not be dumped
1 - (debug) - all processes dump core when possible. The core dump is
owned by the current user and no security is applied. This is intended
for system debugging situations only. Ptrace is unchecked.
2 - (suidsafe) - any binary which normally would not be dumped is dumped
readable by root only. This allows the end user to remove such a dump but
not access it directly. For security reasons core dumps in this mode will
not overwrite one another or other files. This mode is appropriate when
adminstrators are attempting to debug problems in a normal environment.
(akpm:
> > +EXPORT_SYMBOL(suid_dumpable);
>
> EXPORT_SYMBOL_GPL?
No problem to me.
> > if (current->euid == current->uid && current->egid == current->gid)
> > current->mm->dumpable = 1;
>
> Should this be SUID_DUMP_USER?
Actually the feedback I had from last time was that the SUID_ defines
should go because its clearer to follow the numbers. They can go
everywhere (and there are lots of places where dumpable is tested/used
as a bool in untouched code)
> Maybe this should be renamed to `dump_policy' or something. Doing that
> would help us catch any code which isn't using the #defines, too.
Fair comment. The patch was designed to be easy to maintain for Red Hat
rather than for merging. Changing that field would create a gigantic
diff because it is used all over the place.
)
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch to add check to get_chrdev_list and get_blkdev_list to prevent reads
of /proc/devices from spilling over the provided page if more than 4096
bytes of string data are generated from all the registered character and
block devices in a system
Signed-off-by: Neil Horman <nhorman@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add /proc/zoneinfo file to display information about memory zones. Useful
to analyze VM behaviour.
Signed-off-by: Nikita Danilov <nikita@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This cleans up the /proc/device-tree representation of the Open Firmware
device-tree on ppc and ppc64. It does the following things:
- Workaround an issue in some Apple device-trees where a property may
exist with the same name as a child node of the parent. We now
simply "drop" the property instead of creating duplicate entries in
/proc with random result...
- Do not try to chop off the "@0" at the end of a node name whose unit
address is 0. This is not useful, inconsistent, and the code was
buggy and didn't always work anyway.
- Do not create symlinks for the short name and unit address parts of a
node. These were never really used, bloated the memory footprint of
the device-tree with useless struct proc_dir_entry and their matching
dentry and inode cache bloat.
This results in smaller code, smaller memory footprint, and a more
accurate view of the tree presented to userland.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
VmallocTotal: 34359738367 kB
VmallocUsed: 266288 kB
VmallocChunk: 18014366299193295 kB
is unsettling - x86_64 and some other architectures keep a separate address
range for modules in vmalloc's vmlist, which /proc/meminfo should pass over.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some KernelDoc descriptions are updated to match the current code.
No code changes.
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I have recompiled Linux kernel 2.6.11.5 documentation for me and our
university students again. The documentation could be extended for more
sources which are equipped by structured comments for recent 2.6 kernels. I
have tried to proceed with that task. I have done that more times from 2.6.0
time and it gets boring to do same changes again and again. Linux kernel
compiles after changes for i386 and ARM targets. I have added references to
some more files into kernel-api book, I have added some section names as well.
So please, check that changes do not break something and that categories are
not too much skewed.
I have changed kernel-doc to accept "fastcall" and "asmlinkage" words reserved
by kernel convention. Most of the other changes are modifications in the
comments to make kernel-doc happy, accept some parameters description and do
not bail out on errors. Changed <pid> to @pid in the description, moved some
#ifdef before comments to correct function to comments bindings, etc.
You can see result of the modified documentation build at
http://cmp.felk.cvut.cz/~pisa/linux/lkdb-2.6.11.tar.gz
Some more sources are ready to be included into kernel-doc generated
documentation. Sources has been added into kernel-api for now. Some more
section names added and probably some more chaos introduced as result of quick
cleanup work.
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The current logic assumes that a /proc/<PID>/task directory should have a
hardlink count of 3, probably counting ".", "..", and a directory for a
single child task.
It's fairly obvious that this doesn't work out correctly when a PID has
more than one child task, which is quite often the case.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The pid directories in /proc/ currently return the wrong hardlink count - 3,
when there are actually 4 : ".", "..", "fd", and "task".
This is easy to notice using find(1):
cd /proc/<pid>
find
In the output, you'll see a message similar to:
find: WARNING: Hard link count is wrong for .: this may be a bug in your
filesystem driver. Automatically turning on find's -noleaf option.
Earlier results may have failed to include directories that should have
been searched.
http://bugs.gentoo.org/show_bug.cgi?id=86031
I also noticed that CONFIG_SECURITY can add a 5th: attr, and performed a
similar fix on the task directories too.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Attached is a new patch that solves the issue of getting valid credentials
into the LOGIN message. The current code was assuming that the audit context
had already been copied. This is not always the case for LOGIN messages.
To solve the problem, the patch passes the task struct to the function that
emits the message where it can get valid credentials.
Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Working on some code lately I've been getting huge values for "Cached".
The cause is that get_page_cache_size() is an approximate value, and for a
sufficiently small returned value of get_page_cache_size() the value
underflows.
Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
iscsi/lvm2/multipath needs guaranteed protection from the oom-killer, so
make the magical value of -17 in /proc/<pid>/oom_adj defeat the oom-killer
altogether.
(akpm: we still need to document oom_adj and friends in
Documentation/filesystems/proc.txt!)
Signed-off-by: Andrea Arcangeli <andrea@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Eric W. Biederman