This is a real deadlock, a nice complex one:
(warning: long explanation follows so that Andrew can have a complete
patch description)
it's an ABCDA deadlock:
A iprune_mutex
B inode->inotify_mutex
C ih->mutex
D dev->ev_mutex
The AB relationship comes straight from invalidate_inodes()
int invalidate_inodes(struct super_block * sb)
{
int busy;
LIST_HEAD(throw_away);
mutex_lock(&iprune_mutex);
spin_lock(&inode_lock);
inotify_unmount_inodes(&sb->s_inodes);
where inotify_umount_inodes() takes the
mutex_lock(&inode->inotify_mutex);
The BC relationship comes directly from inotify_find_update_watch():
s32 inotify_find_update_watch(struct inotify_handle *ih, struct inode *inode,
u32 mask)
{
...
mutex_lock(&inode->inotify_mutex);
mutex_lock(&ih->mutex);
The CD relationship comes from inotify_rm_wd:
inotify_rm_wd does
mutex_lock(&inode->inotify_mutex);
mutex_lock(&ih->mutex)
and then calls inotify_remove_watch_locked() which calls
notify_dev_queue_event() which does
mutex_lock(&dev->ev_mutex);
(this strictly is a BCD relationship)
The DA relationship comes from the most interesting part:
[<ffffffff8022d9f2>] shrink_icache_memory+0x42/0x270
[<ffffffff80240dc4>] shrink_slab+0x11d/0x1c9
[<ffffffff802b5104>] try_to_free_pages+0x187/0x244
[<ffffffff8020efed>] __alloc_pages+0x1cd/0x2e0
[<ffffffff8025e1f8>] cache_alloc_refill+0x3f8/0x821
[<ffffffff8020a5e5>] kmem_cache_alloc+0x85/0xcb
[<ffffffff802db027>] kernel_event+0x2e/0x122
[<ffffffff8021d61c>] inotify_dev_queue_event+0xcc/0x140
inotify_dev_queue_event schedules a kernel_event which does a
kmem_cache_alloc( , GFP_KERNEL) which may try to shrink slabs, including
the inode cache .. which then takes iprune_mutex.
And voila, there is an AB, a BC, a CD relationship (even a direct BCD),
and also now a DA relationship -> a circular type AB-BA deadlock but
involving 4 locks.
The solution is simple: kernel_event() is NOT allowed to use GFP_KERNEL,
but must use GFP_NOFS to not cause recursion into the VFS.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Robert Love <rml@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Enable mac partition table support per default also for a powermac config.
Signed-off-by: Olaf Hering <olh@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We can immediately bail from invalidate_bdev() if the blockdev has no
pagecache.
This solves the huge IPI storms which hald is causing on the big ia64
machines when it polls CDROM drives.
Acked-by: Jes Sorensen <jes@sgi.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A recent commit (7fc90ec93a) moved the
call to nfsd_setuser out of the 'find a dentry for a filehandle' branch
of fh_verify so that it would always be called.
This had the unfortunately side-effect of moving *after* the call to
decode_fh, so the prober fsuid was not set when nfsd_acceptable was called,
the 'permission' check did the wrong thing.
This patch moves the nfsd_setuser call back where it was, and add as call
in the other branch of the if.
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The inode number out of an NFS file handle gets passed eventually to
ext3_get_inode_block() without any checking. If ext3_get_inode_block()
allows it to trigger an error, then bad filehandles can have unpleasant
effect - ext3_error() will usually cause a forced read-only remount, or a
panic if `errors=panic' was used.
So remove the call to ext3_error there and put a matching check in
ext3/namei.c where inode numbers are read off storage.
[akpm@osdl.org: fix off-by-one error]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: <stable@kernel.org>
Cc: "Stephen C. Tweedie" <sct@redhat.com>
Cc: Eric Sandeen <esandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
flags from iclog buffers before submitting them for writing.
SGI-PV: 954772
SGI-Modid: xfs-linux-melb:xfs-kern:26605a
Signed-off-by: Nathan Scott <nathans@sgi.com>
Before putting them into struct statfs they should be endian-swapped.
SGI-PV: 954580
SGI-Modid: xfs-linux-melb:xfs-kern:26550a
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nathan Scott <nathans@sgi.com>
This just turns off chmod() on the /proc/<pid>/ files, since there is no
good reason to allow it, and had we disallowed it originally, the nasty
/proc race exploit wouldn't have been possible.
The other patches already fixed the problem chmod() could cause, so this
is really just some final mop-up..
This particular version is based off a patch by Eugene and Marcel which
had much better naming than my original equivalent one.
Signed-off-by: Eugene Teo <eteo@redhat.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Export I/O delays seen by a task through /proc/<tgid>/stats for use in top
etc.
Note that delays for I/O done for swapping in pages (swapin I/O) is clubbed
together with all other I/O here (this is not the case in the netlink
interface where the swapin I/O is kept distinct)
[akpm@osdl.org: printk warning fix]
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On systems with block devices containing a slash (virtual dasd, cciss,
etc), reiserfs will fail to initialize /proc/fs/reiserfs/<dev> due to it
being interpreted as a subdirectory. The generic block device code changes
the / to ! for use in the sysfs tree. This patch uses that convention.
Tested by making dm devices use dm/<number> rather than dm-<number>
[akpm@osdl.org: name variables consistently]
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2.6.16 leaks like hell. While testing, I found massive leakage
(reproduced in openvz) in:
*filp
*size-4096
And 1 object leaks in
*size-32
*size-64
*size-128
It is the fix for the first one. filp leaks in the bowels of namei.c.
Seems, size-4096 is file table leaking in expand_fdtables.
I have no idea what are the rest and why they show only accompanying
another leaks. Some debugging structs?
[akpm@osdl.org, Trond: remove the IS_ERR() check]
Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: <stable@kernel.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We have a bad interaction with both the kernel and user space being able
to change some of the /proc file status. This fixes the most obvious
part of it, but I expect we'll also make it harder for users to modify
even their "own" files in /proc.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We're supposed to go the next power of two if nfds==nr.
Of `nr', not of `nfsd'.
Spotted by Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Address a potential 'larger than buffer size' memory access by
clear_user(). Without this patch, this call to clear_user() can attempt to
clear too many (tsz) bytes resulting in a wrong (-EFAULT) return code by
read_kcore().
Signed-off-by: Adam B. Jerome <abj@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sysfs has a different i_mutex lock order behavior for i_mutex than the
other filesystems; sysfs i_mutex is called in many places with subsystem
locks held. At the same time, many of the VFS locking rules do not apply
to sysfs at all (cross directory rename for example). To untangle this
mess (which gives false positives in lockdep), we're giving sysfs inodes
their own class for i_mutex.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When found, it is obvious. nfds calculated when allocating fdsets is
rewritten by calculation of size of fdtable, and when we are unlucky, we
try to free fdsets of wrong size.
Found due to OpenVZ resource management (User Beancounters).
Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add an nfs4 operations count array to nfsd_stats structure. The count is
incremented in nfsd4_proc_compound() where all the operations are handled
by the nfsv4 server. This count of individual nfsv4 operations is also
entered into /proc filesystem.
Signed-off-by: Shankar Anand<shanand@novell.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These functions no longer exist; remove their declarations.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There's a fairly obvious infinite loop in there.
Also, use roundup_pow_of_two() rather than open-coding stuff.
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add coredump capability for the ELF-FDPIC binfmt.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move the roundup() macro from binfmt_elf.c into linux/kernel.h as it's
generally useful.
[akpm@osdl.org: nuke all the other implementations]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adjust the ELF-FDPIC binfmt driver to conform much more to the CodingStyle,
silly though it may be.
Further changes:
(*) Drop the casts to long for addresses in kdebug() statements (they're
unsigned long already).
(*) Use extra variables to avoid expressions longer than 80 chars by splitting
the statement into multiple statements and letting the compiler optimise
them back together.
(*) Eliminate duplicate call of ksize() when working out how much space was
actually allocated for the stack.
(*) Discard the commented-out load_shlib prototype and op pointer as this will
not be supported in ELF-FDPIC for the foreseeable future.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix execution through the FDPIC binfmt of programs stored on ramfs by
preventing the ramfs mmap() returning successfully on a private mapping of
a ramfs file. This causes NOMMU mmap to make a copy of the mapped portion
of the file and map that instead.
This could be improved by granting direct mapping access to read-only
private mappings for which the data is stored on a contiguous run of pages.
However, this is only likely to be the case if the file was extended with
truncate before being written.
ramfs is left to map the file directly for shared mappings so that SYSV IPC
and POSIX shared memory both still work.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix FDPIC compile errors.
(akpm: we suspect it fixes a warning)
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Sometimes, applications need below call to be successful although
"/mnt/hugepages/file1" doesn't exist.
fd = open("/mnt/hugepages/file1", O_CREAT|O_RDWR, 0755);
*addr = mmap(NULL, 0x1024*1024*256, PROT_NONE, 0, fd, 0);
As for regular pages (or files), above call does work, but as for huge
pages, above call would fail because hugetlbfs_file_mmap would fail if
(!(vma->vm_flags & VM_WRITE) && len > inode->i_size).
This capability on huge page is useful on ia64 when the process wants to
protect one area on region 4, so other threads couldn't read/write this
area. A famous JVM (Java Virtual Machine) implementation on IA64 needs the
capability.
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Hugh Dickins <hugh@veritas.com>
[ Expand-on-mmap semantics again... this time matching normal fs's. wli ]
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch marks an unused export as EXPORT_UNUSED_SYMBOL.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change the partition code in fs/partitions/check.c to initialize a newly
detected partition's policy field with that of the containing block device
(see patch below).
My reasoning is that function set_disk_ro() in block/genhd.c modifies the
policy field (read-only indicator) of a disk and all contained partitions.
When a partition is detected after the call to set_disk_ro(), the policy
field of this partition will currently not inherit the disk's policy field.
This behavior poses a problem in cases where a block device can be
'logically de- and reactivated' like e.g. the s390 DASD driver because
partition detection may run after the policy field has been modified.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Makes-sense-to: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When write() extends a file(i_size is increased) and fsync() is called,
change of inode must be written to journaling area through fsync().
But,currently the i_trans_id is not correctly updated when i_size is
increased. So fsync() does not kick the journal writer.
Reiserfs_file_write() already updates the transaction when blocks are
allocated, but the case when i_size increases and new blocks are not added
is not correctly treated.
Following patch fix this bug.
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Chris Mason <mason@suse.com>
Cc: Hans Reiser <reiser@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Several issues noticed/fixed:
- We cannot reliably block in link_pipe() while holding both input and output
mutexes. So do preparatory checks before locking down both mutexes and doing
the link.
- The ipipe->nrbufs vs i check was bad, because we could have dropped the
ipipe lock in-between. This causes us to potentially look at unknown
buffers if we were racing with someone else reading this pipe.
Signed-off-by: Jens Axboe <axboe@suse.de>
In the case when compiling via a symlink tree, we want to ensure that the
close-to-open GETATTR call is applied only to the final file, and not to
the symlink.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The introduction of the FLUSH_INVALIDATE argument to nfs_sync_inode_wait()
does not clear the nr_unstable page state counter for pages that are being
released.
Also fix a longstanding similar bug when nfs_commit_list() fails.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use FL_ACCESS flag to test and/or wait for local locks before we try
requesting a lock from the server
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use the new behaviour of {flock,posix}_file_lock(F_UNLCK) to determine if
we held a lock, and only send the RPC request to the server if this was the
case.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Change posix_lock_file_conf(), and flock_lock_file() so that if called
with an F_UNLCK argument, and the FL_EXISTS flag they will indicate
whether or not any locks were actually freed by returning 0 or -ENOENT.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
cleanup: remove task_t and convert all the uses to struct task_struct. I
introduced it for the scheduler anno and it was a mistake.
Conversion was mostly scripted, the result was reviewed and all
secondary whitespace and style impact (if any) was fixed up by hand.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>