The mandatory file locking implementation has long-standing races that
probably render it useless. I know of no plans to fix them. Till we
do, we should at least warn people.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Shouldn't this mandatory-locking documentation be in the
Documentation/filesystems directory?
Give it a more descriptive name while we're at it, and update 00-INDEX
with a more inclusive description of Documentation/filesystems (which
has already talked about more than just individual filesystems).
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
This code is run under lock_kernel(), which is dropped during
sleeping operations, so the following race is possible:
CPU1: CPU2:
vfs_setlease(); vfs_setlease();
lock_kernel();
lock_kernel(); /* spin */
generic_setlease():
...
for (before = ...)
/* here we found some lease after
* which we will insert the new one
*/
fl = locks_alloc_lock();
/* go to sleep in this allocation and
* drop the BKL
*/
generic_setlease():
...
for (before = ...)
/* here we find the "before" pointing
* at the one we found on CPU1
*/
->fl_change(my_before, arg);
lease_modify();
locks_free_lock();
/* and we freed it */
...
unlock_kernel();
locks_insert_lock(before, fl);
/* OOPS! We have just tried to add the lease
* at the tail of already removed one
*/
The similar races are already handled in other code - all the
allocations are performed before any checks/updates.
Thanks to Kamalesh Babulal for testing and for a bug report on an
earlier version.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
This routine deletes all the elements from the list
with the "while (!list_empty())" loop, and we already
have a list_first_entry() macro to help it look nicer :)
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
This comment wasn't updated when lease support was added, and it makes
essentially the same mistake that the code made before a recent bugfix.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
When the flock_lock_file() is called to change the flock
from F_RDLCK to F_WRLCK or vice versa the existing flock
can be removed without appropriate warning.
Look:
for_each_lock(inode, before) {
struct file_lock *fl = *before;
if (IS_POSIX(fl))
break;
if (IS_LEASE(fl))
continue;
if (filp != fl->fl_file)
continue;
if (request->fl_type == fl->fl_type)
goto out;
found = 1;
locks_delete_lock(before); <<<<<< !
break;
}
if after this point the subsequent locks_alloc_lock() will
fail the return code will be -ENOMEM, but the existing lock
is already removed.
This is a known feature that such "re-locking" is not atomic,
but in the racy case the file should stay locked (although by
some other process), but in this case the file will be unlocked.
The proposal is to prepare the lock in advance keeping no chance
to fail in the future code.
Found during making the flocks pid-namespaces aware.
(Note: Thanks to Reuben Farrelly for finding a bug in an earlier version
of this patch.)
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Reuben Farrelly <reuben-linuxkernel@reub.net>
There's no need for another variable local to this loop; we can use the
variable (of the same name!) already declared at the top of the function,
and not used till later (at which point it's initialized, so this is safe).
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The first argument to posix_locks_conflict() is meant to be a lock request,
and the second a lock from an inode's lock request. It doesn't really
make a difference which order you call them in, since the only
asymmetric test in posix_lock_conflict() is the check whether the second
argument is a posix lock--and every caller already does that check for
some reason.
But may as well fix posix_test_lock() to call posix_locks_conflict()
with the arguments in the same order as everywhere else.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Au1000: set the PCI controller IO base
[MIPS] Alchemy: Fix USB initialization.
[MIPS] IP32: Fix fatal typo in address computation.
The recent fix for a circular lock dependency unfortunately introduced a
potential memory leak in the event where the call to nlmsvc_lookup_host
fails for some reason.
Thanks to Roel Kluin for spotting this.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The recent mv_fill_sg() rewrite, to fix a data corruption problem
related to IOMMU virtual merging, forgot to account for the
potentially-increased size of the scatter/gather table after its run.
Additionally, the DMA boundary is reduced from 0xffffffff to 0xffff
to more closely match the needs of mv_fill_sg().
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The PCI controller IO base was not set in the au1000 pci code.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch fixes a wrong ifdef in the board setup code, leading to the GPIO
pin not being pulled high, and thus the USB switch not being powered at all.
This finishes the rename of CONFIG_USB_OHCI to CONFIG_USB_OHCI_HCD, which
started in 2005 (before 2.6.12-rc2), then probably because things were
working anyway for most people got forgotten.
[Ralf: Paolo's original patch didn't fix the module case, Florian's patch
only fixed MTX1 etc. so this is a combined patch plus some cleanups.]
Cc: Giuseppe Patanè <giuseppe.patane@tvblob.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When building a custom keymap, after setting GENERATE_KEYMAP := 1 in
drivers/char/Makefile, the kernel build fails like this:
CC drivers/char/vt.o
make[2]: *** No rule to make target `drivers/char/%.map', needed by `drivers/char/defkeymap.c'. Stop.
make[1]: *** [drivers/char] Error 2
make: *** [drivers] Error 2
This was caused by commit af8b128719, which
deleted a necessary colon from the Makefile rule that generates the keymap,
since that rule contains both a target and a target-pattern. The following
patch puts the colon back:
Signed-off-by: Maarten Bressers <mbres@gentoo.org>
Cc: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix against access random data bytes outside the dev->chanmap array.
Thanks to Oliver Neukum for pointing me to this issue.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When IOCB_FLAG_RESFD flag is set and iocb->aio_resfd is incorrect,
statement 'goto out_put_req' is executed. At label 'out_put_req',
aio_put_req(..) is called, which requires 'req->ki_filp' set.
Signed-off-by: Yan Zheng<yanzheng@21cn.com>
Cc: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
find_lock_page increases page's usage count, we should decrease it
before return VM_FAULT_SIGBUS
Signed-off-by: Yan Zheng<yanzheng@21cn.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The test for VM_CAN_NONLINEAR always fails
Signed-off-by: Yan Zheng<yanzheng@21cn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All the current page_mkwrite() implementations also set the page dirty. Which
results in the set_page_dirty_balance() call to _not_ call balance, because the
page is already found dirty.
This allows us to dirty a _lot_ of pages without ever hitting
balance_dirty_pages(). Not good (tm).
Force a balance call if ->page_mkwrite() was successful.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When the ICMPv6 Target address is multicast, Linux processes the
redirect instead of dropping it. The problem is in this code in
ndisc_redirect_rcv():
if (ipv6_addr_equal(dest, target)) {
on_link = 1;
} else if (!(ipv6_addr_type(target) & IPV6_ADDR_LINKLOCAL)) {
ND_PRINTK2(KERN_WARNING
"ICMPv6 Redirect: target address is not
link-local.\n");
return;
}
This second check will succeed if the Target address is, for example,
FF02::1 because it has link-local scope. Instead, it should be checking
if it's a unicast link-local address, as stated in RFC 2461/4861 Section
8.1:
- The ICMP Target Address is either a link-local address (when
redirected to a router) or the same as the ICMP Destination
Address (when redirected to the on-link destination).
I know this doesn't explicitly say unicast link-local address, but it's
implied.
This bug is preventing Linux kernels from achieving IPv6 Logo Phase II
certification because of a recent error that was found in the TAHI test
suite - Neighbor Disovery suite test 206 (v6LC.2.3.6_G) had the
multicast address in the Destination field instead of Target field, so
we were passing the test. This won't be the case anymore.
The patch below fixes this problem, and also fixes ndisc_send_redirect()
to not send an invalid redirect with a multicast address in the Target
field. I re-ran the TAHI Neighbor Discovery section to make sure Linux
passes all 245 tests now.
Signed-off-by: Brian Haley <brian.haley@hp.com>
Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When only GSO skb was partially ACKed, no hints are reset,
therefore fastpath_cnt_hint must be tweaked too or else it can
corrupt fackets_out. The corruption to occur, one must have
non-trivial ACK/SACK sequence, so this bug is not very often
that harmful. There's a fackets_out state reset in TCP because
fackets_out is known to be inaccurate and that fixes the issue
eventually anyway.
In case there was also at least one skb that got fully ACKed,
the fastpath_skb_hint is set to NULL which causes a recount for
fastpath_cnt_hint (the old value won't be accessed anymore),
thus it can safely be decremented without additional checking.
Reported by Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should only reparent to a class former class devices that
form the base of class hierarchy. Nested devices should still
grow from their real parents.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Tested-by: Andrey Borzenkov <arvidjaar@mail.ru>
Tested-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the manufacturer and card id of teltonica pcmcia modems to serial_cs.c
Signed-off-by: Attila Kinali <attila@kinali.ch>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Document sequence of keypresses that actually works. Yes, this changed
year-or-so ago.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Async signals should not be reported as sent by current in audit log. As
it is, we call audit_signal_info() too early in check_kill_permission().
Note that check_kill_permission() has that test already - it needs to know
if it should apply current-based permission checks. So the solution is to
move the call of audit_signal_info() between those.
Bogosity in question is easily reproduced - add a rule watching for e.g.
kill(2) from specific process (so that audit_signal_info() would not
short-circuit to nothing), say load_policy, watch the bogus OBJ_PID entry
in audit logs claiming that write(2) on selinuxfs file issued by
load_policy(8) had somehow managed to send a signal to syslogd...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Steve Grubb <sgrubb@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide some documentation for CONFIG_LOCK_STAT.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
VIA C3 Ezra-T has RevisionID equal to 1, but it needs RevisionKey to be 0
or CPU will ignore new frequency and will continue to work at old
frequency. New "revid_errata" option will force RevisionKey to be set to
0, whatever RevisionID is.
Additionaly "Longhaul" will not silently ignore unsuccessful transition.
It will try to check if "revid_errata" or "disable_acpi_c3" options need to
be enabled for this processor/system.
Same for Longhaul ver. 2 support. It will be disabled if none of above
options will work.
Best case scenario (with patch apllied and v2 enabled):
longhaul: VIA C3 'Ezra' [C5C] CPU detected. Longhaul v2 supported.
longhaul: Using northbridge support.
longhaul: VRM 8.5
longhaul: Max VID=1.350 Min VID=1.050, 13 possible voltage scales
longhaul: f: 300000 kHz, index: 0, vid: 1050 mV
[...]
longhaul: Voltage scaling enabled.
Worst case scenario:
longhaul: VIA C3 'Ezra-T' [C5M] CPU detected. Powersaver supported.
longhaul: Using northbridge support.
longhaul: Using ACPI support.
longhaul: VRM 8.5
longhaul: Claims to support voltage scaling but min & max are both 1.250. Voltage scaling disabled
longhaul: Failed to set requested frequency!
longhaul: Enabling "Ignore Revision ID" option.
longhaul: Failed to set requested frequency!
longhaul: Disabling ACPI C3 support.
longhaul: Disabling "Ignore Revision ID" option.
longhaul: Failed to set requested frequency!
longhaul: Enabling "Ignore Revision ID" option.
[akpm@linux-foundation.org: coding-style cleanups]
Signed-off-by: Rafal Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using /proc/timer_stats on ppc64 I noticed the events/sec field wasnt
accurate. Sometimes the integer part was incorrect due to rounding (we
werent taking the fractional seconds into consideration).
The fraction part is also wrong, we need to pad the printf statement and
take the bottom three digits of 1000 times the value.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that there are a few other five-second timers in the
kernel, and if the timers get in sync, the load-average can get
artificially inflated by events that just happen to coincide.
So just offset the load average calculation it by a timer tick.
Noticed by Anders Boström, for whom the coincidence started triggering
on one of his machines with the JBD jiffies rounding code (JBD is one of
the subsystems that also end up using a 5-second timer by default).
Tested-by: Anders Boström <anders@bostrom.dyndns.org>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should generally prefer to return ERESTARTNOHAND rather than EINTR,
so that processes with unhandled signals that get ignored don't return
EINTR.
This can help with X startup issues:
Fatal server error:
xf86OpenConsole: VT_WAITACTIVE failed: Interrupted system call
although the real fix is having the X server always retry EINTR
regardless (since EINTR does happen for signals that have handlers
installed). Keithp has a patch for that.
Regardless, ERESTARTNOHAND is the correct thing to use.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit f443675aff, which
breaks horribly if you aren't running an unreleased xf86-video-intel
driver out of git.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Zhenyu Wang <zhenyu.z.wang@intel.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The PCI device table in the powermac IDE driver isn't properly
terminated. Depending on how your kernel is linked and other random
factors, you can end up with this driver matched against any other PCI
device in your system, possibly crashing at boot.
Thanks to Heikki for tracking this down with me, the bug have been there
for some time, though it rarely hurts due to luck. In this case, the
switch from .22 to .23-rc9 is causing it to show up due to differences
in the resulting layout of .data I suppose.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <pmac@au1.ibm.com>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Heikki Lindholm <holindho@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When pinning and unpinning pagetables, we must protect them against
being used by other CPUs, lest they see the pagetable in an
intermediate read-only-but-not-pinned state.
When using split pte locks, doing this properly would require taking
all the pte locks for the pagetable while pinning, but this may overflow
the PREEMPT_BITS part of the preempt counter if the process has mapped
more than about 512M of memory.
However, failing to take the pte locks causes write-protect faults when
the pageout code is trying to clear the Access bit on a pte which is part
of a freshy created and still being pinned process after fork.
This is a short-term fix until the problem is solved properly.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Keir Fraser <keir@xensource.com>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] 4598/2: OSIRIS: Ensure we do not get nRSTOUT during suspend
[ARM] 4597/2: OSIRIS: ensure CPLD0 is preserved after suspend
Ensure nRSTOUT is not asserted during or on resume.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ensure that CPLD is restored to the original state
on resume, and that before going into suspend we
select the NAND bank we booted from for restarting.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The 8169/8110SC currently announces itself as:
[...]
eth0: RTL8169sc/8110sc at 0x........, ..:..:..:..:..:.., XID 18000000 IRQ ..
^^^^^^^^
It uses RTL_GIGA_MAC_VER_05 and this part of the changeset can cut
its performance by a factor of 2~2.5 as reported by Timo.
(the driver includes code just before the hunk to write the ChipCmd
register when mac_version == RTL_GIGA_MAC_VER_0[1-4])
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Timo Jantunen <jeti@welho.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
[SPARC64]: Fix 'niu' complex IRQ probing.
[SPARC64]: check fork_idle() error
[SPARC64]: Temporary workaround for PCI-E slot on T1000.
[SPARC64]: VIO device addition log message level is too high.
[SPARC64]: Fix domain-services port probing.
[SPARC64]: Don't use in/local regs for ldx/stx data in N1 memcpy.
It is ok to call prefetch() function with NULL argument, as specifically
commented in include/linux/prefetch.h. But in standard C, it is invalid
to dereference NULL pointer (see C99 standard 6.5.3.2 paragraph 4 and
note #84).
prefetch() has a memory reference for its argument.
Newer gcc versions (4.3 and above) will use that to conclude that "x"
argument is non-null and thus wreaking havok everywhere prefetch() was
inlined.
Fixed by removing cast and changing asm constraint.
[ It seems in theory gcc 4.2 could miscompile this too; although no
cases known. In 2.6.24 we should probably switch to
__builtin_prefetch() instead, but this is a simpler fix for now.
-- AK ]
Signed-off-by: Serge Belyshev <belyshev@depni.sinp.msu.ru>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixe MACE PCI addressing by adding the bus number parameter.
Remove check of the used slot since every slot should be valid.
Converted mkaddr from #define to inline function.
Signed-off-by: Giuseppe Sacco <eppesuig@debian.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
J. Bruce Fields