In davinci_vcif_trigger() function, a break() statement was missing
causing the davinci_vcif_stop() function to be called as a fallback
after calling davinci_vcif_start().
Signed-off-by: Rajashekhara, Sudhakar <sudhakar.raj@ti.com> Acked-by: Liam Girdwood <lrg@ti.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ben reported a lockup related to rtc. The lockup happens due to:
CPU0 CPU1
rtc_irq_set_state() __run_hrtimer()
spin_lock_irqsave(&rtc->irq_task_lock) rtc_handle_legacy_irq();
spin_lock(&rtc->irq_task_lock);
hrtimer_cancel()
while (callback_running);
So the running callback never finishes as it's blocked on
rtc->irq_task_lock.
Use hrtimer_try_to_cancel() instead and drop rtc->irq_task_lock while
waiting for the callback. Fix this for both rtc_irq_set_state() and
rtc_irq_set_freq().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: Ben Greear <greearb@candelatech.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1477) fixes a problem affecting a few types of EHCI
controller. Contrary to what one might expect, these controllers
automatically stop their internal frame counter when no ports are
enabled. Since ehci-hcd currently relies on the frame counter for
determining when it should unlink QHs from the async schedule, those
controllers run into trouble: The frame counter stops and the QHs
never get unlinked.
Some systems have also experienced other problems traced back to
commit b963801164618e25fbdc0cd452ce49c3628b46c8 (USB: ehci-hcd unlink
speedups), which made the original switch from using the system clock
to using the frame counter. It never became clear what the reason was
for these problems, but evidently it is related to use of the frame
counter.
To fix all these problems, this patch more or less reverts that commit
and goes back to using the system clock. But this can't be done
cleanly because other changes have since been made to the scan_async()
subroutine. One of these changes involved the tricky logic that tries
to avoid rescanning QHs that have already been seen when the scanning
loop is restarted, which happens whenever an URB is given back.
Switching back to clock-based unlinks would make this logic even more
complicated.
Therefore the new code doesn't rescan the entire async list whenever a
giveback occurs. Instead it rescans only the current QH and continues
on from there. This requires the use of a separate pointer to keep
track of the next QH to scan, since the current QH may be unlinked
while the scanning is in progress. That new pointer must be global,
so that it can be adjusted forward whenever the _next_ QH gets
unlinked. (uhci-hcd uses this same trick.)
Simplification of the scanning loop removes a level of indentation,
which accounts for the size of the patch. The amount of code changed
is relatively small, and it isn't exactly a reversion of the b963801164 commit.
This fixes Bugzilla #32432.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Matej Kenda <matejken@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The NVIDIA series of OHCI controllers continues to be troublesome. A
few people using the MCP67 chipset have reported that even with the
most recent kernels, the OHCI controller fails to handle new
connections and spams the system log with "unable to enumerate USB
port" messages. This is different from the other problems previously
reported for NVIDIA OHCI controllers, although it is probably related.
It turns out that the MCP67 controller does not like to be kept in the
RESET state very long. After only a few seconds, it decides not to
work any more. This patch (as1479) changes the PCI initialization
quirk code so that NVIDIA controllers are switched into the SUSPEND
state after 50 ms of RESET. With no interrupts enabled and all the
downstream devices reset, and thus unable to send wakeup requests,
this should be perfectly safe (even for non-NVIDIA hardware).
The removal code in ohci-hcd hasn't been changed; it will still leave
the controller in the RESET state. As a result, if someone unloads
ohci-hcd and then reloads it, the controller won't work again until
the system is rebooted. If anybody complains about this, the removal
code can be updated similarly.
This fixes Bugzilla #22052.
Tested-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On some loaded windows hosts, we have discovered that the host may not
respond to guest requests within the specified time (one second)
as evidenced by the guest timing out. Fix this problem by increasing
the timeout to 5 seconds.
It may be useful to apply this patch to the 3.0 kernel as well.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Hank Janssen <hjanssen@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On some loaded windows hosts, we have discovered that the host may not
respond to guest requests within the specified time (one second)
as evidenced by the guest timing out. Fix this problem by increasing
the timeout to 5 seconds.
It may be useful to apply this patch to the 3.0 kernel as well.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Hank Janssen <hjanssen@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On some loaded windows hosts, we have discovered that the host may not
respond to guest requests within the specified time (one second)
as evidenced by the guest timing out. Fix this problem by increasing
the timeout to 5 seconds.
It may be useful to apply this patch to the 3.0 kernel as well.
the 3.0 kernel as well.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Hank Janssen <hjanssen@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
driver_name and board_name are pointers to strings, not buffers of size
COMEDI_NAMELEN. Copying COMEDI_NAMELEN bytes of a string containing
less than COMEDI_NAMELEN-1 bytes would leak some unrelated bytes.
There are two devices with PCI ID 0x10ec:0x8192, namely RTL8192E and
RTL8192SE. The method of distinguishing them is by the revision ID
at offset 0x8 of the PCI configuration space. If the value is 0x10,
then the device uses rtl8192se for a driver.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When unbinding a device on the host which was still attached on the
client, I got a NULL pointer dereference on the client. This turned out
to be due to kthread_stop() being called on an already dead kthread.
Currently skb_gro_header_slow unconditionally resets frag0 and
frag0_len. However, when we can't pull on the skb this leaves
the GRO fields in an inconsistent state.
This patch fixes this by only resetting those fields after the
pskb_may_pull test.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
What is supposed to happen:
* bridge with the lowest ID is elected root (for example: B)
* C detects that A->C is higher cost path and puts in blocking state
What happens. Bridge with lowest id (B) is elected correctly as
root and things start out fine initially. But then config BPDU
doesn't get transmitted from A -> C. Because of that
the link from A-C is transistioned to the forwarding state.
The root cause of this is that the configuration messages
is generated with bogus message age, and dropped before
sending.
In the standardmessage_age is supposed to be:
the time since the generation of the Configuration BPDU by
the Root that instigated the generation of this Configuration BPDU.
Reimplement this by recording the timestamp (age + jiffies) when
recording config information. The old code incorrectly used the time
elapsed on the ageing timer which was incorrect.
See also:
https://bugzilla.vyatta.com/show_bug.cgi?id=7164
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The function esdhc_readl_le intends to clear bit SDHCI_CARD_PRESENT,
when the card detect gpio tells there is no card. But it does not
clear the bit actually. The patch gives a fix on that.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Chris Ball <cjb@laptop.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ricoh 1180:e823 does not recognize certain types of SD/MMC cards,
as reported at http://launchpad.net/bugs/773524. Lowering the SD
base clock frequency from 200Mhz to 50Mhz fixes this issue. This
solution was suggest by Koji Matsumuro, Ricoh Company, Ltd.
This change has no negative performance effect on standard SD
cards, though it's quite possible that there will be one on
UHS-1 cards.
Signed-off-by: Manoj Iyer <manoj.iyer@canonical.com> Tested-by: Daniel Manrique <daniel.manrique@canonical.com> Cc: Koji Matsumuro <matsumur@nts.ricoh.co.jp> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Chris Ball <cjb@laptop.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Make Dell Latitude E6420 use reboot=pci
x86: Make Dell Latitude E5420 use reboot=pci
H. Peter Anvin [Thu, 21 Jul 2011 18:22:21 +0000 (11:22 -0700)]
x86: Make Dell Latitude E6420 use reboot=pci
Yet another variant of the Dell Latitude series which requires
reboot=pci.
From the E5420 bug report by Daniel J Blueman:
> The E6420 is affected also (same platform, different casing and
> features), which provides an external confirmation of the issue; I can
> submit a patch for that later or include it if you prefer:
> http://linux.koolsolutions.com/2009/08/04/howto-fix-linux-hangfreeze-during-reboots-and-restarts/
Reported-by: Daniel J Blueman <daniel.blueman@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@kernel.org>
Daniel J Blueman [Fri, 13 May 2011 01:04:59 +0000 (09:04 +0800)]
x86: Make Dell Latitude E5420 use reboot=pci
Rebooting on the Dell E5420 often hangs with the keyboard or ACPI
methods, but is reliable via the PCI method.
[ hpa: this was deferred because we believed for a long time that the
recent reshuffling of the boot priorities in commit 660e34cebf0a11d54f2d5dd8838607452355f321 fixed this platform.
Unfortunately that turned out to be incorrect. ]
vfs: drop conditional inode prefetch in __do_lookup_rcu
It seems to hurt performance in real life. Yes, the inode will be used
later, but the conditional doesn't seem to predict all that well
(negative dentries are not uncommon) and it looks like the cost of
prefetching is simply higher than depending on the cache doing the right
thing.
The compiler, at least for ix86 and m68k, validly warns that the
comparison:
next <= (loff_t)-1
is always true (and it's always true also for x86-64 and probably all
other arches - as long as pgoff_t isn't wider than loff_t). The
intention appears to be to avoid wrapping of "next", so rather than
eliminating the pointless comparison, fix the loop to indeed get exited
when "next" would otherwise wrap.
On m68k the following warning is observed:
fs/fscache/page.c: In function '__fscache_uncache_all_inode_pages':
fs/fscache/page.c:979: warning: comparison is always false due to limited range of data type
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Reported-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Suresh Jayaraman <sjayaraman@suse.de> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Avoid creating superfluous NUMA domains on non-NUMA systems
sched: Allow for overlapping sched_domain spans
sched: Break out cpu_power from the sched_group structure
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86. reboot: Make Dell Latitude E6320 use reboot=pci
x86, doc only: Correct real-mode kernel header offset for init_size
x86: Disable AMD_NUMA for 32bit for now
Paul E. McKenney [Tue, 19 Jul 2011 10:25:36 +0000 (03:25 -0700)]
signal: align __lock_task_sighand() irq disabling and RCU
The __lock_task_sighand() function calls rcu_read_lock() with interrupts
and preemption enabled, but later calls rcu_read_unlock() with interrupts
disabled. It is therefore possible that this RCU read-side critical
section will be preempted and later RCU priority boosted, which means that
rcu_read_unlock() will call rt_mutex_unlock() in order to deboost itself, but
with interrupts disabled. This results in lockdep splats, so this commit
nests the RCU read-side critical section within the interrupt-disabled
region of code. This prevents the RCU read-side critical section from
being preempted, and thus prevents the attempt to deboost with interrupts
disabled.
It is quite possible that a better long-term fix is to make rt_mutex_unlock()
disable irqs when acquiring the rt_mutex structure's ->wait_lock.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Peter Zijlstra [Tue, 19 Jul 2011 22:32:00 +0000 (15:32 -0700)]
softirq,rcu: Inform RCU of irq_exit() activity
The rcu_read_unlock_special() function relies on in_irq() to exclude
scheduler activity from interrupt level. This fails because exit_irq()
can invoke the scheduler after clearing the preempt_count() bits that
in_irq() uses to determine that it is at interrupt level. This situation
can result in failures as follows:
$task IRQ SoftIRQ
rcu_read_lock()
/* do stuff */
<preempt> |= UNLOCK_BLOCKED
rcu_read_unlock()
--t->rcu_read_lock_nesting
irq_enter();
/* do stuff, don't use RCU */
irq_exit();
sub_preempt_count(IRQ_EXIT_OFFSET);
invoke_softirq()
Ed can simply trigger this 'easy' because invoke_softirq() immediately
does a ttwu() of ksoftirqd/# instead of doing the in-place softirq stuff
first, but even without that the above happens.
Cure this by also excluding softirqs from the
rcu_read_unlock_special() handler and ensuring the force_irqthreads
ksoftirqd/# wakeup is done from full softirq context.
[ Alternatively, delaying the ->rcu_read_lock_nesting decrement
until after the special handling would make the thing more robust
in the face of interrupts as well. And there is a separate patch
for that. ]
Cc: Thomas Gleixner <tglx@linutronix.de> Reported-and-tested-by: Ed Tomlinson <edt@aei.ca> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Peter Zijlstra [Tue, 19 Jul 2011 22:07:25 +0000 (15:07 -0700)]
sched: Add irq_{enter,exit}() to scheduler_ipi()
Ensure scheduler_ipi() calls irq_{enter,exit} when it does some actual
work. Traditionally we never did any actual work from the resched IPI
and all magic happened in the return from interrupt path.
Now that we do do some work, we need to ensure irq_{enter,exit} are
called so that we don't confuse things.
This affects things like timekeeping, NO_HZ and RCU, basically
everything with a hook in irq_enter/exit.
Explicit examples of things going wrong are:
sched_clock_cpu() -- has a callback when leaving NO_HZ state to take
a new reading from GTOD and TSC. Without this
callback, time is stuck in the past.
RCU -- needs in_irq() to work in order to avoid some nasty deadlocks
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Mon, 18 Jul 2011 04:14:35 +0000 (21:14 -0700)]
rcu: protect __rcu_read_unlock() against scheduler-using irq handlers
The addition of RCU read-side critical sections within runqueue and
priority-inheritance lock critical sections introduced some deadlock
cycles, for example, involving interrupts from __rcu_read_unlock()
where the interrupt handlers call wake_up(). This situation can cause
the instance of __rcu_read_unlock() invoked from interrupt to do some
of the processing that would otherwise have been carried out by the
task-level instance of __rcu_read_unlock(). When the interrupt-level
instance of __rcu_read_unlock() is called with a scheduler lock held
from interrupt-entry/exit situations where in_irq() returns false,
deadlock can result.
This commit resolves these deadlocks by using negative values of
the per-task ->rcu_read_lock_nesting counter to indicate that an
instance of __rcu_read_unlock() is in flight, which in turn prevents
instances from interrupt handlers from doing any special processing.
This patch is inspired by Steven Rostedt's earlier patch that similarly
made __rcu_read_unlock() guard against interrupt-mediated recursion
(see https://lkml.org/lkml/2011/7/15/326), but this commit refines
Steven's approach to avoid the need for preemption disabling on the
__rcu_read_unlock() fastpath and to also avoid the need for manipulating
a separate per-CPU variable.
This patch avoids need for preempt_disable() by instead using negative
values of the per-task ->rcu_read_lock_nesting counter. Note that nested
rcu_read_lock()/rcu_read_unlock() pairs are still permitted, but they will
never see ->rcu_read_lock_nesting go to zero, and will therefore never
invoke rcu_read_unlock_special(), thus preventing them from seeing the
RCU_READ_UNLOCK_BLOCKED bit should it be set in ->rcu_read_unlock_special.
This patch also adds a check for ->rcu_read_unlock_special being negative
in rcu_check_callbacks(), thus preventing the RCU_READ_UNLOCK_NEED_QS
bit from being set should a scheduling-clock interrupt occur while
__rcu_read_unlock() is exiting from an outermost RCU read-side critical
section.
Of course, __rcu_read_unlock() can be preempted during the time that
->rcu_read_lock_nesting is negative. This could result in the setting
of the RCU_READ_UNLOCK_BLOCKED bit after __rcu_read_unlock() checks it,
and would also result it this task being queued on the corresponding
rcu_node structure's blkd_tasks list. Therefore, some later RCU read-side
critical section would enter rcu_read_unlock_special() to clean up --
which could result in deadlock if that critical section happened to be in
the scheduler where the runqueue or priority-inheritance locks were held.
This situation is dealt with by making rcu_preempt_note_context_switch()
check for negative ->rcu_read_lock_nesting, thus refraining from
queuing the task (and from setting RCU_READ_UNLOCK_BLOCKED) if we are
already exiting from the outermost RCU read-side critical section (in
other words, we really are no longer actually in that RCU read-side
critical section). In addition, rcu_preempt_note_context_switch()
invokes rcu_read_unlock_special() to carry out the cleanup in this case,
which clears out the ->rcu_read_unlock_special bits and dequeues the task
(if necessary), in turn avoiding needless delay of the current RCU grace
period and needless RCU priority boosting.
It is still illegal to call rcu_read_unlock() while holding a scheduler
lock if the prior RCU read-side critical section has ever had either
preemption or irqs enabled. However, the common use case is legal,
namely where then entire RCU read-side critical section executes with
irqs disabled, for example, when the scheduler lock is held across the
entire lifetime of the RCU read-side critical section.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Peter Zijlstra [Wed, 20 Jul 2011 16:42:57 +0000 (18:42 +0200)]
sched: Avoid creating superfluous NUMA domains on non-NUMA systems
When creating sched_domains, stop when we've covered the entire
target span instead of continuing to create domains, only to
later find they're redundant and throw them away again.
This avoids single node systems from touching funny NUMA
sched_domain creation code and reduces the risks of the new
SD_OVERLAP code.
Peter Zijlstra [Fri, 15 Jul 2011 08:35:52 +0000 (10:35 +0200)]
sched: Allow for overlapping sched_domain spans
Allow for sched_domain spans that overlap by giving such domains their
own sched_group list instead of sharing the sched_groups amongst
each-other.
This is needed for machines with more than 16 nodes, because
sched_domain_node_span() will generate a node mask from the
16 nearest nodes without regard if these masks have any overlap.
Currently sched_domains have a sched_group that maps to their child
sched_domain span, and since there is no overlap we share the
sched_group between the sched_domains of the various CPUs. If however
there is overlap, we would need to link the sched_group list in
different ways for each cpu, and hence sharing isn't possible.
In order to solve this, allocate private sched_groups for each CPU's
sched_domain but have the sched_groups share a sched_group_power
structure such that we can uniquely track the power.
Reported-and-tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-08bxqw9wis3qti9u5inifh3y@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
Shaohua Li [Tue, 19 Jul 2011 15:49:26 +0000 (08:49 -0700)]
vmscan: fix a livelock in kswapd
I'm running a workload which triggers a lot of swap in a machine with 4
nodes. After I kill the workload, I found a kswapd livelock. Sometimes
kswapd3 or kswapd2 are keeping running and I can't access filesystem,
but most memory is free.
This looks like a regression since commit 08951e545918c159 ("mm: vmscan:
correct check for kswapd sleeping in sleeping_prematurely").
Node 2 and 3 have only ZONE_NORMAL, but balance_pgdat() will return 0
for classzone_idx. The reason is end_zone in balance_pgdat() is 0 by
default, if all zones have watermark ok, end_zone will keep 0.
Later sleeping_prematurely() always returns true. Because this is an
order 3 wakeup, and if classzone_idx is 0, both balanced_pages and
present_pages in pgdat_balanced() are 0. We add a special case here.
If a zone has no page, we think it's balanced. This fixes the livelock.
Signed-off-by: Shaohua Li <shaohua.li@intel.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A value larger than INT_MAX cannot be written to the debugfs file created
by debugfs_create_u64 or debugfs_create_x64 on 32bit machine. Because
simple_attr_write() uses simple_strtol() for the conversion.
To fix this, use simple_strtoll() instead.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Don't update *inode in __follow_mount_rcu() until we'd verified that
there is mountpoint there. Kudos to Hugh Dickins for catching that
one in the first place and eventually figuring out the solution (and
catching a braino in the earlier version of patch).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Paul E. McKenney [Sat, 21 May 2011 12:57:18 +0000 (05:57 -0700)]
rcu: Streamline code produced by __rcu_read_unlock()
Given some common flag combinations, particularly -Os, gcc will inline
rcu_read_unlock_special() despite its being in an unlikely() clause.
Use noinline to prohibit this misoptimization.
In addition, move the second barrier() in __rcu_read_unlock() so that
it is not on the common-case code path. This will allow the compiler to
generate better code for the common-case path through __rcu_read_unlock().
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
The RCU_BOOST commits for TREE_PREEMPT_RCU introduced an other-task
write to a new RCU_READ_UNLOCK_BOOSTED bit in the task_struct structure's
->rcu_read_unlock_special field, but, as noted by Steven Rostedt, without
correctly synchronizing all accesses to ->rcu_read_unlock_special.
This could result in bits in ->rcu_read_unlock_special being spuriously
set and cleared due to conflicting accesses, which in turn could result
in deadlocks between the rcu_node structure's ->lock and the scheduler's
rq and pi locks. These deadlocks would result from RCU incorrectly
believing that the just-ended RCU read-side critical section had been
preempted and/or boosted. If that RCU read-side critical section was
executed with either rq or pi locks held, RCU's ensuing (incorrect)
calls to the scheduler would cause the scheduler to attempt to once
again acquire the rq and pi locks, resulting in deadlock. More complex
deadlock cycles are also possible, involving multiple rq and pi locks
as well as locks from multiple rcu_node structures.
This commit fixes synchronization by creating ->rcu_boosted field in
task_struct that is accessed and modified only when holding the ->lock
in the rcu_node structure on which the task is queued (on that rcu_node
structure's ->blkd_tasks list). This results in tasks accessing only
their own current->rcu_read_unlock_special fields, making unsynchronized
access once again legal, and keeping the rcu_read_unlock() fastpath free
of atomic instructions and memory barriers.
The reason that the rcu_read_unlock() fastpath does not need to access
the new current->rcu_boosted field is that this new field cannot
be non-zero unless the RCU_READ_UNLOCK_BLOCKED bit is set in the
current->rcu_read_unlock_special field. Therefore, rcu_read_unlock()
need only test current->rcu_read_unlock_special: if that is zero, then
current->rcu_boosted must also be zero.
This bug does not affect TINY_PREEMPT_RCU because this implementation
of RCU accesses current->rcu_read_unlock_special with irqs disabled,
thus preventing races on the !SMP systems that TINY_PREEMPT_RCU runs on.
Maybe-reported-by: Dave Jones <davej@redhat.com> Maybe-reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Paul E. McKenney [Sun, 17 Jul 2011 09:05:49 +0000 (02:05 -0700)]
rcu: decrease rcu_report_exp_rnp coupling with scheduler
PREEMPT_RCU read-side critical sections blocking an expedited grace
period invoke rcu_report_exp_rnp(). When the last such critical section
has completed, rcu_report_exp_rnp() invokes the scheduler to wake up the
task that invoked synchronize_rcu_expedited() -- needlessly holding the
root rcu_node structure's lock while doing so, thus needlessly providing
a way for RCU and the scheduler to deadlock.
This commit therefore releases the root rcu_node structure's lock before
calling wake_up().
Reported-by: Ed Tomlinson <edt@aei.ca> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Chris Wilson [Mon, 18 Jul 2011 20:11:49 +0000 (13:11 -0700)]
drm/i915: Fix unfenced alignment on pre-G33 hardware
Align unfenced buffers on older hardware to the power-of-two object
size. The docs suggest that it should be possible to align only to a
power-of-two tile height, but using the already computed fence size is
easier and always correct. We also have to make sure that we unbind
misaligned buffers upon tiling changes.
In order to prevent a repetition of this bug, we change the interface
to the alignment computation routines to force the caller to provide
the requested alignment and size of the GTT binding rather than assume
the current values on the object.
Reported-and-tested-by: Sitosfe Wheeler <sitsofe@yahoo.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=36326 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@kernel.org Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Keith Packard <keithp@keithp.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
pppoe: Must flush connections when MAC address changes too.
include/linux/sdla.h: remove the prototype of sdla()
tulip: dmfe: Remove old log spamming pr_debugs
Al Viro [Mon, 18 Jul 2011 17:50:40 +0000 (13:50 -0400)]
Fix cifs_get_root()
Add missing ->i_mutex, convert to lookup_one_len() instead of
(broken) open-coded analog, cope with getting something like
a//b as relative pathname. Simplify the hell out of it, while
we are there...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Jeff Layton <jlayton@redhat.com>
Joe Perches [Mon, 18 Jul 2011 17:44:44 +0000 (10:44 -0700)]
tulip: dmfe: Remove old log spamming pr_debugs
Commit 726b65ad444d ("tulip: Convert uses of KERN_DEBUG") enabled
some old previously inactive uses of pr_debug converted by
commit dde7c8ef1679 ("tulip/dmfe.c: Use dev_<level> and pr_<level>").
Remove these pr_debugs.
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
si4713-i2c: avoid potential buffer overflow on si4713
While compiling it with Fedora 15, I noticed this issue:
inlined from ‘si4713_write_econtrol_string’ at drivers/media/radio/si4713-i2c.c:1065:24:
arch/x86/include/asm/uaccess_32.h:211:26: error: call to ‘copy_from_user_overflow’ declared with attribute error: copy_from_user() buffer size is not provably correct
Al Viro [Mon, 18 Jul 2011 02:27:22 +0000 (22:27 -0400)]
hppfs_lookup(): don't open-code lookup_one_len()
... and it's getting it wrong, too - missing ->d_revalidate() calls when
it's dealing with filesystem (procfs) that has non-trivial ->d_revalidate()...
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] update cifs to version 1.74
[CIFS] update limit for snprintf in cifs_construct_tcon
cifs: Fix signing failure when server mandates signing for NTLMSSP
Merge branch 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung
* 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
ARM: SAMSUNG: DMA Cleanup as per sparse
ARM: SAMSUNG: Check NULL return from irq_alloc_generic_chip
spi_sync call uses its spi_message parameter to keep completion information,
using a drvdata structure is not thread-safe. Use a mutex to prevent
multiple access to shared driver data.
Signed-off-by: Pavel Herrmann <morpheus.ibis@gmail.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Marek Vasut <marek.vasut@gmail.com> Acked-by: Cyril Hrubis <metan@ucw.cz> Tested-by: Stanislav Brabec <utx@penguin.cz> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: stable@kernel.org
Jean Delvare [Sun, 17 Jul 2011 16:39:19 +0000 (18:39 +0200)]
hwmon: (it87) Fix label group removal
A copy-and-paste error caused it87_attributes_vid to be referenced
where it87_attributes_label should be. Thankfully the group is only
used for attribute removal, not attribute creation, so the effects of
this bug are limited, but let's fix it still.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: stable@kernel.org Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Randy Dunlap [Sat, 16 Jul 2011 19:25:49 +0000 (12:25 -0700)]
watchdog: hpwdt depends on PCI
hpwdt is a PCI driver so it should depend on PCI.
Fixes these build errors:
drivers/watchdog/hpwdt.c:762: error: implicit declaration of function 'pci_iomap'
drivers/watchdog/hpwdt.c:762: warning: assignment makes pointer from integer without a cast
drivers/watchdog/hpwdt.c:797: error: implicit declaration of function 'pci_iounmap'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be> Cc: Thomas Mingarelli <thomas.mingarelli@hp.com>
Mark Brown [Thu, 14 Jul 2011 09:21:37 +0000 (18:21 +0900)]
ASoC: Correct WM8994 MICBIAS supply widget hookup
The WM8994 and WM8958 series of devices have two MICBIAS supplies rather
than one, the current widget actually manages the microphone detection
control register bit (which is managed separately by the relevant API).
Fix this, hooking the relevant supplies up to the MICBIAS1 and MICBIAS2
widgets.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@kernel.org
Al Viro [Sun, 17 Jul 2011 03:37:20 +0000 (23:37 -0400)]
cifs: build_path_from_dentry() race fix
deal with d_move() races properly; rename_lock read-retry loop,
rcu_read_lock() held while walking to root, d_lock held over
subtraction from namelen and copying the component to stabilize
->d_name.
Will Simoneau [Sat, 16 Jul 2011 17:45:12 +0000 (10:45 -0700)]
sparc: sun4m SMP: fix wrong shift instruction in IPI handler
This shift instruction appears to be shifting in the wrong direction.
Without this change, my SparcStation-20MP hangs just after bringing up
the second CPU:
Entering SMP Mode...
Starting CPU 2 at f02b4e90
Brought up 2 CPUs
Total of 2 processors activated (99.52 BogoMIPS).
*** stuck ***
Signed-off-by: Will Simoneau <simoneau@ele.uri.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilia Kolomisnky [Fri, 15 Jul 2011 18:30:21 +0000 (18:30 +0000)]
Bluetooth: Fix crash with incoming L2CAP connections
Another regression fix considering incomming l2cap connections with
defer_setup enabled. In situations when incomming connection is
extracted with l2cap_sock_accept, it's bt_sock info will have
'parent' member zerroed, but 'parent' may be used unconditionally
in l2cap_conn_start() and l2cap_security_cfm() when defer_setup
is enabled.
Backtrace:
[<bf02d5ac>] (l2cap_security_cfm+0x0/0x2ac [bluetooth]) from [<bf01f01c>] (hci_event_pac
ket+0xc2c/0x4aa4 [bluetooth])
[<bf01e3f0>] (hci_event_packet+0x0/0x4aa4 [bluetooth]) from [<bf01a844>] (hci_rx_task+0x
cc/0x27c [bluetooth])
[<bf01a778>] (hci_rx_task+0x0/0x27c [bluetooth]) from [<c008eee4>] (tasklet_action+0xa0/
0x15c)
[<c008ee44>] (tasklet_action+0x0/0x15c) from [<c008f38c>] (__do_softirq+0x98/0x130)
r7:00000101 r6:00000018 r5:00000001 r4:efc46000
[<c008f2f4>] (__do_softirq+0x0/0x130) from [<c008f524>] (do_softirq+0x4c/0x58)
[<c008f4d8>] (do_softirq+0x0/0x58) from [<c008f5e0>] (run_ksoftirqd+0xb0/0x1b4)
r4:efc46000 r3:00000001
[<c008f530>] (run_ksoftirqd+0x0/0x1b4) from [<c009f2a8>] (kthread+0x84/0x8c)
r7:00000000 r6:c008f530 r5:efc47fc4 r4:efc41f08
[<c009f224>] (kthread+0x0/0x8c) from [<c008cc84>] (do_exit+0x0/0x5f0)
Signed-off-by: Ilia Kolomisnky <iliak@ti.com> Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi> Signed-off-by: David S. Miller <davem@davemloft.net>
Bluetooth: Fix regression with incoming L2CAP connections
PTS test A2DP/SRC/SRC_SET/TC_SRC_SET_BV_02_I revealed that
( probably after the df3c3931e commit ) the l2cap connection
could not be established in case when the "Auth Complete" HCI
event does not arive before the initiator send "Configuration
request", in which case l2cap replies with "Command rejected"
since the channel is still in BT_CONNECT2 state.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi> Signed-off-by: David S. Miller <davem@davemloft.net>
Sangwook Lee [Sat, 16 Jul 2011 06:50:19 +0000 (15:50 +0900)]
ARM: SAMSUNG: DMA Cleanup as per sparse
Function declaration differs between file: dma.c and file:dma.h
and SPARSE (Documentation/sparse.txt) gives error messages
All dma channels are members of 'enum dma_ch' and not 'unsigned int'
Please have a look at channel definitions in:
arch/arm/mach-s3c64xx/include/mach/dma.h
arch/arm/plat-samsung/include/plat/s3c-dma-pl330.h
arch/arm/mach-s3c2410/include/mach/dma.h
So all arguments should be of type 'enum dma_ch'
Signed-off-by: Sangwook Lee <sangwook.lee@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Olaf Hering [Fri, 15 Jul 2011 21:23:33 +0000 (23:23 +0200)]
watchdog: fix hpwdt Kconfig regression in 3.0-rc
Remove Kconfig regression caused by commit a4616153deae053b29a2b7dd9ec4b2a225accfc5 "watchdog: hpwdt: build hpwdt as
module by default with NMI_DECODING enabled"
With the above change applied, hpwdt will be enabled unconditionally by just
entering the Watchdog subscreen in menuconfig. Since this driver is not
essential to boot any box it should remain disabled until it gets manually
enabled, just like all other drivers.
Signed-off-by: Olaf Hering <olaf@aepfle.de> Cc: Tony Camuso <tcamuso@redhat.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
clocksource: convert ARM 32-bit up counting clocksources
broke the build for ixp4xx and made big endian operation impossible.
This commit restores the original behaviour.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at> Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
[ Thomas says that we might want to have generic BE accessor functions
to the MMIO clock source, but that hasn't happened yet, so in the
meantime this seems to be the short-term fix for the particular
problem - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sebastian Pöhn [Fri, 15 Jul 2011 23:00:20 +0000 (16:00 -0700)]
gianfar: rx parser
Only let the rx parser be enabled if it is necessary (if VLAN extraction,
IP or TCP checksumming or the rx queue filer are enabled). Otherwise
disable it.
The new routine gfar_check_rx_parser_mode should be run after every
change on this features and will enable/disable the parser as necessary.
Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: Sebastian Poehn <sebastian.poehn@belden.com> Signed-off-by: David S. Miller <davem@davemloft.net>
The code in arch/mips/kernel/i8259.c still hasn't been converted to
using struct syscore_ops instead of a sysdev for resume and shutdown.
As a result, this code doesn't build any more after suspend, resume
and shutdown callbacks have been removed from struct sysdev_class.
Fix this problem by converting i8259.c to using syscore_ops.
Reported-and-tested-by: Roland Vossen <rvossen@broadcom.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Ralf Baechle <ralf@linux-mips.org>
Axel Lin [Sun, 10 Jul 2011 07:45:07 +0000 (15:45 +0800)]
gpio: wm831x: add a missing break in wm831x_gpio_dbg_show
Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging:
hwmon: (adm1275) Fix coefficients per datasheet revision B
hwmon: (pmbus) Use long variables for register to data conversions
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
fix loop checks in d_materialise_unique()
Fix ->d_lock locking order in unlazy_walk()
Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu
* 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu:
rcu: Prevent RCU callbacks from executing before scheduler initialized
projects / karo-tx-linux.git / log