* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6:
[SCSI] aic79xx: make driver respect nvram for IU and QAS settings
[SCSI] don't attach ULD to Dell Universal Xport
[SCSI] lpfc 8.3.3 : Update driver version to 8.3.3
[SCSI] lpfc 8.3.3 : Add support for Target Reset handler entrypoint
[SCSI] lpfc 8.3.3 : Fix a couple of spin_lock and memory issues and a crash
[SCSI] lpfc 8.3.3 : FC/FCOE discovery fixes
[SCSI] lpfc 8.3.3 : Fix various SLI-3 vs SLI-4 differences
[SCSI] qla2xxx: Resolve a performance issue in interrupt
[SCSI] cnic, bnx2i: Fix build failure when CONFIG_PCI is not set.
[SCSI] nsp_cs: time_out reaches -1
[SCSI] qla2xxx: fix printk format warnings
[SCSI] ncr53c8xx: div reaches -1
[SCSI] compat: don't perform unneeded copy in sg_io code
[SCSI] zfcp: Update FC pass-through support
[SCSI] zfcp: Add FC pass-through support
[SCSI] FC Pass Thru support
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
UBIFS: start using hrtimers
hrtimer: export ktime_add_safe
UBIFS: do not forget to register BDI device
UBIFS: allow sync option in rootflags
UBIFS: remove dead code
UBIFS: use anonymous device
UBIFS: return proper error code if the compr is not present
UBIFS: return error if link and unlink race
UBIFS: reset no_space flag after inode deletion
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (47 commits)
MIPS: Add hibernation support
MIPS: Move Cavium CP0 hwrena impl bits to cpu-feature-overrides.h
MIPS: Allow CPU specific overriding of CP0 hwrena impl bits.
MIPS: Kconfig Add SYS_SUPPORTS_HUGETLBFS and enable it for some systems.
Hugetlbfs: Enable hugetlbfs for more systems in Kconfig.
MIPS: TLB support for hugetlbfs.
MIPS: Add hugetlbfs page defines.
MIPS: Add support files for hugetlbfs.
MIPS: Remove unused parameters from iPTE_LW.
Staging: Add octeon-ethernet driver files.
MIPS: Export erratum function needed by octeon-ethernet driver.
MIPS: Cavium-Octeon: Add more chip specific feature tests.
MIPS: Cavium-Octeon: Add more board type constants.
MIPS: Export cvmx_sysinfo_get needed by octeon-ethernet driver.
MIPS: Add named alloc functions to OCTEON boot monitor memory allocator.
MIPS: Alchemy: devboards: Convert to gpio calls.
MIPS: Alchemy: xxs1500: use linux gpio api.
MIPS: Alchemy: MTX-1: Use linux gpio api.
MIPS: Alchemy: Rewrite GPIO support.
MIPS: Alchemy: Remove unused au1000_gpio.h header
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
get rid of BKL in fs/sysv
get rid of BKL in fs/minix
get rid of BKL in fs/efs
befs ->pust_super() doesn't need BKL
Cleanup of adfs headers
9P doesn't need BKL in ->umount_begin()
fuse doesn't need BKL in ->umount_begin()
No instance of ->bmap() needs BKL
remove unlock_kernel() left accidentally
ext4: avoid unnecessary spinlock in critical POSIX ACL path
ext3: avoid unnecessary spinlock in critical POSIX ACL path
As part of adding hugetlbfs support for MIPS, I am adding a new
kconfig variable 'SYS_SUPPORTS_HUGETLBFS'. Since some mips cpu
varients don't yet support it, we can enable selection of HUGETLBFS on
a system by system basis from the arch/mips/Kconfig.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
CC: William Irwin <wli@holomorphy.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
commit 337eb00a2c
Push BKL down into ->remount_fs()
and
commit 4aa98cf768
Push BKL down into do_remount_sb()
were uncorrectly merged.
The former removes one pair of lock/unlock_kernel(), but the latter adds
several unlock_kernel(). Finally a few unlock_kernel() calls left.
Signed-off-by: J. R. Okajima <hooanon05@yahoo.co.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If a filesystem supports POSIX ACL's, the VFS layer expects the filesystem
to do POSIX ACL checks on any files not owned by the caller, and it does
this for every single pathname component that it looks up.
That obviously can be pretty expensive if the filesystem isn't careful
about it, especially with locking. That's doubly sad, since the common
case tends to be that there are no ACL's associated with the files in
question.
ext4 already caches the ACL data so that it doesn't have to look it up
over and over again, but it does so by taking the inode->i_lock spinlock
on every lookup. Which is a noticeable overhead even if it's a private
lock, especially on CPU's where the serialization is expensive (eg Intel
Netburst aka 'P4').
For the special case of not actually having any ACL's, all that locking is
unnecessary. Even if somebody else were to be changing the ACL's on
another CPU, we simply don't care - if we've seen a NULL ACL, we might as
well use it.
So just load the ACL speculatively without any locking, and if it was
NULL, just use it. If it's non-NULL (either because we had a cached
entry, or because the cache hasn't been filled in at all), it means that
we'll need to get the lock and re-load it properly.
(This commit was ported from a patch originally authored by Linus for
ext3.)
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If a filesystem supports POSIX ACL's, the VFS layer expects the filesystem
to do POSIX ACL checks on any files not owned by the caller, and it does
this for every single pathname component that it looks up.
That obviously can be pretty expensive if the filesystem isn't careful
about it, especially with locking. That's doubly sad, since the common
case tends to be that there are no ACL's associated with the files in
question.
ext3 already caches the ACL data so that it doesn't have to look it up
over and over again, but it does so by taking the inode->i_lock spinlock
on every lookup. Which is a noticeable overhead even if it's a private
lock, especially on CPU's where the serialization is expensive (eg Intel
Netburst aka 'P4').
For the special case of not actually having any ACL's, all that locking is
unnecessary. Even if somebody else were to be changing the ACL's on
another CPU, we simply don't care - if we've seen a NULL ACL, we might as
well use it.
So just load the ACL speculatively without any locking, and if it was
NULL, just use it. If it's non-NULL (either because we had a cached
entry, or because the cache hasn't been filled in at all), it means that
we'll need to get the lock and re-load it properly.
This is noticeable even on Nehalem, which does locking quite well (much
better than P4). From lmbench:
Processor, Processes - times in microseconds - smaller is better
--------------------------------------------------------------------
Host OS Mhz null null open slct fork exec sh
call I/O stat clos TCP proc proc proc
--------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ----
- before:
nehalem.l Linux 2.6.30- 3193 0.04 0.09 0.95 1.45 2.18 69.1 273. 1141
nehalem.l Linux 2.6.30- 3193 0.04 0.09 0.95 1.48 2.28 69.9 253. 1140
nehalem.l Linux 2.6.30- 3193 0.04 0.10 0.95 1.42 2.19 68.6 284. 1141
- after:
nehalem.l Linux 2.6.30- 3193 0.04 0.09 0.92 1.44 2.12 68.3 282. 1094
nehalem.l Linux 2.6.30- 3193 0.04 0.09 0.92 1.39 2.20 67.0 308. 1123
nehalem.l Linux 2.6.30- 3193 0.04 0.09 0.92 1.39 2.36 67.4 293. 1148
where you can see what appears to be a roughly 3% improvement in stat
and open/close latencies from just the removal of the locking overhead.
Of course, this only matters for files you don't own (the owner never
needs to do the ACL checks), but that's the common case for libraries,
header files, and executables. As well as for the base components of any
absolute pathname, even if you are the owner of the final file.
[ At some point we probably want to move this ACL caching logic entirely
into the VFS layer (and only call down to the filesystem when
uncached), but in the meantime this improves ext3 a bit.
A similar fix to btrfs makes a much bigger difference (15x improvement
in lmbench) due to broken caching. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Authentication error abort codes should be translated to appropriate
Linux error codes, rather than all being translated to EREMOTEIO - which
indicates that the server had internal problems.
Additionally, a server shouldn't be marked unavailable and the next
server tried if an authentication error occurs. This will quickly make
all the servers unavailable to the client. Instead the error should be
returned straight to the user.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* akpm: (182 commits)
fbdev: bf54x-lq043fb: use kzalloc over kmalloc/memset
fbdev: *bfin*: fix __dev{init,exit} markings
fbdev: *bfin*: drop unnecessary calls to memset
fbdev: bfin-t350mcqb-fb: drop unused local variables
fbdev: blackfin has __raw I/O accessors, so use them in fb.h
fbdev: s1d13xxxfb: add accelerated bitblt functions
tcx: use standard fields for framebuffer physical address and length
fbdev: add support for handoff from firmware to hw framebuffers
intelfb: fix a bug when changing video timing
fbdev: use framebuffer_release() for freeing fb_info structures
radeon: P2G2CLK_ALWAYS_ONb tested twice, should 2nd be P2G2CLK_DAC_ALWAYS_ONb?
s3c-fb: CPUFREQ frequency scaling support
s3c-fb: fix resource releasing on error during probing
carminefb: fix possible access beyond end of carmine_modedb[]
acornfb: remove fb_mmap function
mb862xxfb: use CONFIG_OF instead of CONFIG_PPC_OF
mb862xxfb: restrict compliation of platform driver to PPC
Samsung SoC Framebuffer driver: add Alpha Channel support
atmel-lcdc: fix pixclock upper bound detection
offb: use framebuffer_alloc() to allocate fb_info struct
...
Manually fix up conflicts due to kmemcheck in mm/slab.c
CONFIG_FILE_LOCKING should not depend on CONFIG_BLOCK.
This makes it possible to run complete systems out of a CONFIG_BLOCK=n
initramfs on current kernels again (this last worked on 2.6.27.*).
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
put_cpu_no_resched() is an optimization of put_cpu() which unfortunately
can cause high latencies.
The nfs iostats code uses put_cpu_no_resched() in a code sequence where a
reschedule request caused by an interrupt between the get_cpu() and the
put_cpu_no_resched() can delay the reschedule for at least HZ.
The other users of put_cpu_no_resched() optimize correctly in interrupt
code, but there is no real harm in using the put_cpu() function which is
an alias for preempt_enable(). The extra check of the preemmpt count is
not as critical as the potential source of missing a reschedule.
Debugged in the preempt-rt tree and verified in mainline.
Impact: remove a high latency source
[akpm@linux-foundation.org: build fix]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After introduction of keyed wakeups Davide Libenzi did on epoll, we are
able to avoid spurious wakeups in poll()/select() code too.
For example, typical use of poll()/select() is to wait for incoming
network frames on many sockets. But TX completion for UDP/TCP frames call
sock_wfree() which in turn schedules thread.
When scheduled, thread does a full scan of all polled fds and can sleep
again, because nothing is really available. If number of fds is large,
this cause significant load.
This patch makes select()/poll() aware of keyed wakeups and useless
wakeups are avoided. This reduces number of context switches by about 50%
on some setups, and work performed by sofirq handlers.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1) I_FREEING tests should be coupled with I_CLEAR
The two I_FREEING tests are racy because clear_inode() can set i_state to
I_CLEAR between the clear of I_SYNC and the test of I_FREEING.
2) skip I_WILL_FREE inodes in generic_sync_sb_inodes() to avoid possible
races with generic_forget_inode()
generic_forget_inode() sets I_WILL_FREE call writeback on its own, so
generic_sync_sb_inodes() shall not try to step in and create possible races:
generic_forget_inode
inode->i_state |= I_WILL_FREE;
spin_unlock(&inode_lock);
generic_sync_sb_inodes()
spin_lock(&inode_lock);
__iget(inode);
__writeback_single_inode
// see non zero i_count
may WARN here ==> WARN_ON(inode->i_state & I_WILL_FREE);
spin_unlock(&inode_lock);
may call generic_forget_inode again ==> iput(inode);
The above race and warning didn't turn up because writeback_inodes() holds
the s_umount lock, so generic_forget_inode() finds MS_ACTIVE and returns
early. But we are not sure the UBIFS calls and future callers will
guarantee that. So skip I_WILL_FREE inodes for the sake of safety.
Cc: Eric Sandeen <sandeen@sandeen.net>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove __invalidate_mapping_pages atomic variant now that its sole caller
can sleep (fixed in eccb95cee4 ("vfs: fix
lock inversion in drop_pagecache_sb()")).
This fixes softlockups that can occur while in the drop_caches path.
Signed-off-by: Mike Waychison <mikew@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The per-task oom_adj value is a characteristic of its mm more than the
task itself since it's not possible to oom kill any thread that shares the
mm. If a task were to be killed while attached to an mm that could not be
freed because another thread were set to OOM_DISABLE, it would have
needlessly been terminated since there is no potential for future memory
freeing.
This patch moves oomkilladj (now more appropriately named oom_adj) from
struct task_struct to struct mm_struct. This requires task_lock() on a
task to check its oom_adj value to protect against exec, but it's already
necessary to take the lock when dereferencing the mm to find the total VM
size for the badness heuristic.
This fixes a livelock if the oom killer chooses a task and another thread
sharing the same memory has an oom_adj value of OOM_DISABLE. This occurs
because oom_kill_task() repeatedly returns 1 and refuses to kill the
chosen task while select_bad_process() will repeatedly choose the same
task during the next retry.
Taking task_lock() in select_bad_process() to check for OOM_DISABLE and in
oom_kill_task() to check for threads sharing the same memory will be
removed in the next patch in this series where it will no longer be
necessary.
Writing to /proc/pid/oom_adj for a kthread will now return -EINVAL since
these threads are immune from oom killing already. They simply report an
oom_adj value of OOM_DISABLE.
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Export all page flags faithfully in /proc/kpageflags.
11. KPF_MMAP (pseudo flag) memory mapped page
12. KPF_ANON (pseudo flag) memory mapped page (anonymous)
13. KPF_SWAPCACHE page is in swap cache
14. KPF_SWAPBACKED page is swap/RAM backed
15. KPF_COMPOUND_HEAD (*)
16. KPF_COMPOUND_TAIL (*)
17. KPF_HUGE hugeTLB pages
18. KPF_UNEVICTABLE page is in the unevictable LRU list
19. KPF_HWPOISON(TBD) hardware detected corruption
20. KPF_NOPAGE (pseudo flag) no page frame at the address
32-39. more obscure flags for kernel developers
(*) For compound pages, exporting _both_ head/tail info enables
users to tell where a compound page starts/ends, and its order.
The accompanying page-types tool will handle the details like decoupling
overloaded flags and hiding obscure flags to normal users.
Thanks to KOSAKI and Andi for their valuable recommendations!
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
send_sigio_to_task() reads fown->signum several times, we can race with
F_SETSIG which changes ->signum lockless. In theory, this can fool
security checks or we can call group_send_sig_info() with the wrong
->si_signo which does not match "int sig".
Change the code to cache ->signum.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shift current_cred() from __f_setown() to f_modown(). This reduces
the number of arguments and saves 48 bytes from fs/fcntl.o.
[ Note: this doesn't clear euid/uid when pid is set to NULL. But if
f_owner.pid == NULL we never use f_owner.uid/euid. Otherwise we'd
have a bug anyway: we must not send signals if pid was reset to NULL. ]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (64 commits)
debugfs: use specified mode to possibly mark files read/write only
debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem.
xen: remove driver_data direct access of struct device from more drivers
usb: gadget: at91_udc: remove driver_data direct access of struct device
uml: remove driver_data direct access of struct device
block/ps3: remove driver_data direct access of struct device
s390: remove driver_data direct access of struct device
parport: remove driver_data direct access of struct device
parisc: remove driver_data direct access of struct device
of_serial: remove driver_data direct access of struct device
mips: remove driver_data direct access of struct device
ipmi: remove driver_data direct access of struct device
infiniband: ehca: remove driver_data direct access of struct device
ibmvscsi: gadget: at91_udc: remove driver_data direct access of struct device
hvcs: remove driver_data direct access of struct device
xen block: remove driver_data direct access of struct device
thermal: remove driver_data direct access of struct device
scsi: remove driver_data direct access of struct device
pcmcia: remove driver_data direct access of struct device
PCIE: remove driver_data direct access of struct device
...
Manually fix up trivial conflicts due to different direct driver_data
direct access fixups in drivers/block/{ps3disk.c,ps3vram.c}
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
ocfs2/net: Use wait_event() in o2net_send_message_vec()
ocfs2: Adjust rightmost path in ocfs2_add_branch.
ocfs2: fdatasync should skip unimportant metadata writeout
ocfs2: Remove redundant gotos in ocfs2_mount_volume()
ocfs2: Add statistics for the checksum and ecc operations.
ocfs2 patch to track delayed orphan scan timer statistics
ocfs2: timer to queue scan of all orphan slots
ocfs2: Correct ordering of ip_alloc_sem and localloc locks for directories
ocfs2: Fix possible deadlock in quota recovery
ocfs2: Fix possible deadlock with quotas in ocfs2_setattr()
ocfs2: Fix lock inversion in ocfs2_local_read_info()
ocfs2: Fix possible deadlock in ocfs2_global_read_dquot()
ocfs2: update comments in masklog.h
ocfs2: Don't printk the error when listing too many xattrs.
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: remove some includings of blktrace_api.h
mg_disk: seperate mg_disk.h again
block: Introduce helper to reset queue limits to default values
cfq: remove extraneous '\n' in blktrace output
ubifs: register backing_dev_info
btrfs: properly register fs backing device
block: don't overwrite bdi->state after bdi_init() has been run
cfq: cleanup for last_end_request in cfq_data
Commit fec1878fe9 caused a regression in
which contiguous blocks being allocated to the end of an extent were
getting a new extent created. This typically results in files entirely
made up of 1-block extents even though the blocks are contiguous on
disk.
Apparently grub doesn't handle a jfs file being fragmented into too many
extents, since it refuses to boot a kernel from jfs that was created by
the 2.6.30 kernel.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Reported-by: Alex <alevkovich@tut.by>
When porting blktrace to tracepoints, we changed to trace/block.h
for trace prober declarations.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
btrfs assigns this bdi to all inodes on that file system, so make
sure it's registered. This isn't really important now, but will be
when we put dirty inodes there. Even now, we miss the stats when the
bdi isn't visible.
Also fixes failure to check bdi_init() return value, and bad inherit of
->capabilities flags from the default bdi.
Acked-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch (as1239) updates the kernel's treatment of Unicode. The
character-set conversion routines are well behind the current state of
the Unicode specification: They don't recognize the existence of code
points beyond plane 0 or of surrogate pairs in the UTF-16 encoding.
The old wchar_t 16-bit type is retained because it's still used in
lots of places. This shouldn't cause any new problems; if a
conversion now results in an invalid 16-bit code then before it must
have yielded an undefined code.
Difficult-to-read names like "utf_mbstowcs" are replaced with more
transparent names like "utf8s_to_utf16s" and the ordering of the
parameters is rationalized (buffer lengths come immediate after the
pointers they refer to, and the inputs precede the outputs).
Fortunately the low-level conversion routines are used in only a few
places; the interfaces to the higher-level uni2char and char2uni
methods have been left unchanged.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
utf8_wcstombs forgot to include one-byte UTF-8 characters when
calculating the output buffer size, i.e., theoretically, it was possible
to overflow the output buffer with an input string that contains enough
ASCII characters.
In practice, this was no problem because the only user so far (VFAT)
always uses a big enough output buffer.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When utf8_wcstombs encounters a character that cannot be encoded, we
must not decrease the remaining output buffer size because nothing has
been written to the output buffer.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In many SoC implementations there are hardware registers can be read or
write only. This extends the debugfs to enforce the file permissions for
these types of registers by providing a set of fops which are read or
write only. This assumes that the kernel developer knows more about the
hardware than the user (even root users) -- which is normally true.
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fix an error in debugfs_create_blob's docbook description
It cannot actually be used to write a binary blob.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
debugfs: dont stop on first failed recursive delete
While running a while loop of removing a module that removes a debugfs
directory with debugfs_remove_recursive, and at the same time doing a
while loop of cat of a file in that directory, I would hit a point where
somehow the cat of the file caused the remove to fail.
The result is that other files did not get removed when the module
was removed. I simple read of one of those file can oops the kernel
because the operations to the file no longer exist (removed by module).
The funny thing is that the file being cat'ed was removed. It was
the siblings that were not. I see in the code to debugfs_remove_recursive
there's a test that checks if the child fails to bail out of the loop
to prevent an infinite loop.
What this patch does is to still try any siblings in that directory.
If all the siblings fail, or there are no more siblings, then we exit
the loop.
This fixes the above symptom, but...
This is no full proof. It makes the debugfs_remove_recursive a bit more
robust, but it does not explain why the one file failed. There may
be some kind of delay deletion that makes the debugfs think it did
not succeed. So this patch is more of a fix for the symptom but not
the disease.
This patch still makes the debugfs_remove_recursive more robust and
until I can find out why the bug exists, this patch will keep
the kernel from oopsing in most cases. Even after the cause is found
I think this change can stand on its own and should be kept.
[ Impact: prevent kernel oops on module unload and reading debugfs files ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There is the possiblity of a memory leak if a page is allocated and if
sysfs_getlink() fails in the sysfs_follow_link.
Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
commit_fs_roots skips updating root items for fs trees that aren't modified.
This is unsafe now that relocation code modifies root item's last_snapshot
field without modifying corresponding fs tree.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
