On platforms that have __ARCH_WANT_UNLOCKED_CTXSW set and want to implement
lock validator support there's a bug in rq->lock handling: in this case we
dont 'carry over' the runqueue lock into another task - but still we did a
spinlock_release() of it. Fix this by making the spinlock_release() in
context_switch() dependent on !__ARCH_WANT_UNLOCKED_CTXSW.
(Reported by Ralf Baechle on MIPS, which has __ARCH_WANT_UNLOCKED_CTXSW.
This fixes a lockdep-internal BUG message on such platforms.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Resolve problems seen w/ APM suspend.
Due to resume initialization ordering, its possible we could get a timer
interrupt before the timekeeping resume() function is called. This patch
ensures we don't do any timekeeping accounting before we're fully resumed.
(akpm: fixes the machine-freezes-on-APM-resume bug)
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Christoph Hellwig:
open_softirq just enables a softirq. The softirq array is statically
allocated so to add a new one you would have to patch the kernel. So
there's no point to keep this export at all as any user would have to
patch the enum in include/linux/interrupt.h anyway.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When CONFIG_RT_MUTEX_TESTER is enabled kernel refuses to suspend the
machine because it's unable to freeze the rt-test-* threads.
Add try_to_freeze() after schedule() so that the threads will be freezed
correctly; I've tested the patch and it lets the notebook suspends and
resumes nicely.
Signed-off-by: Luca Tettamanti <kronos.it@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Got a customer bug report (https://bugzilla.novell.com/190296) about kernel
symbols longer than 127 characters which end up in a string buffer that is
not NULL terminated, leading to garbage in /proc/kallsyms. Using strlcpy
prevents this from happening, even though such symbols still won't come out
right.
A better fix would be to not use a fixed-size buffer, but it's probably not
worth the trouble. (Modversion'ed symbols even have a length limit of 60.)
[bunk@stusta.de: build fix]
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement the scheduled unexport of insert_resource.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove the deprecated and no longer used pm_unregister_all().
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Based on a patch from Ernie Petrides
During security research, Red Hat discovered a behavioral flaw in core
dump handling. A local user could create a program that would cause a
core file to be dumped into a directory they would not normally have
permissions to write to. This could lead to a denial of service (disk
consumption), or allow the local user to gain root privileges.
The prctl() system call should never allow to set "dumpable" to the
value 2. Especially not for non-privileged users.
This can be split into three cases:
1) running as root -- then core dumps will already be done as root,
and so prctl(PR_SET_DUMPABLE, 2) is not useful
2) running as non-root w/setuid-to-root -- this is the debatable case
3) running as non-root w/setuid-to-non-root -- then you definitely
do NOT want "dumpable" to get set to 2 because you have the
privilege escalation vulnerability
With case #2, the only potential usefulness is for a program that has
designed to run with higher privilege (than the user invoking it) that
wants to be able to create root-owned root-validated core dumps. This
might be useful as a debugging aid, but would only be safe if the program
had done a chdir() to a safe directory.
There is no benefit to a production setuid-to-root utility, because it
shouldn't be dumping core in the first place. If this is true, then the
same debugging aid could also be accomplished with the "suid_dumpable"
sysctl.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Disable lockdep debugging in two situations where the integrity of the
kernel no longer is guaranteed: when oopsing and when hitting a
tainting-condition. The goal is to not get weird lockdep traces that don't
make sense or are otherwise undebuggable, to not waste time.
Lockdep assumes that the previous state it knows about is valid to operate,
which is why lockdep turns itself off after the first violation it reports,
after that point it can no longer make that assumption.
A kernel oops means that the integrity of the kernel compromised; in
addition anything lockdep would report is of lesser importance than the
oops.
All the tainting conditions are of similar integrity-violating nature and
also make debugging/diagnosing more difficult.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As announced half a year ago this patch will remove the tasklist_lock
export. The previous two patches got rid of the remaining modular users.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
allyesconfig vmlinux size delta:
text data bss dec filename
20736884 6073834 3075176 29885894 vmlinux.before
20721009 6073966 3075176 29870151 vmlinux.after
~18 bytes per callsite, 15K of text size (~0.1%) saved.
(as an added bonus this also removes a lockdep annotation.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Do not panic a machine when swsusp signature can't be read.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
kernel/power/swap.c: In function 'swsusp_write':
kernel/power/swap.c:275: warning: 'start' may be used uninitialized in this function
gcc isn't smart enough, so help it.
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
swsusp should not use memcpy for snapshotting memory, because on some
architectures memcpy may increase preempt_count (i386 does this when
CONFIG_X86_USE_3DNOW is set). Then, as a result, wrong value of preempt_count
is stored in the image.
Replace memcpy in copy_data_pages with an open-coded loop.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A large number of lost ticks can cause an overadjustment of the clock. To
compensate for this we look at the current error and the larger the error
already is the more careful we are at adjusting the error. As small extra
fix reset the error when the clock is set.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Acked-by: john stultz <johnstul@us.ibm.com>
Cc: Uwe Bugla <uwe.bugla@gmx.de>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Calling futex_lock_pi is called with a reference to a non PI futex and
waiters exist already, lookup_pi_state() oopses due to pi_state == NULL.
Check this condition and return -EINVAL to userspace.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jakub Jelinek <jakub@redhat.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>
This patch marks unused exports as EXPORT_SYMBOL_UNUSED.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
lockdep_map is embedded into every lock, which blows up data structure
sizes all around the kernel. Reduce the class-cache to be for the default
class only - that is used in 99.9% of the cases and even if we dont have a
class cached, the lookup in the class-hash is lockless.
This change reduces the per-lock dep_map overhead by 56 bytes on 64-bit
platforms and by 28 bytes on 32-bit platforms.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make lockdep print which lock is held, in the "kfree() of a live lock"
scenario.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- constify and optimize stat_nam (thanks to Michael Tokarev!)
- spelling and comment fixes
Signed-off-by: Andreas Mohr <andi@lisas.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
