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506,942 commits

Author SHA1 Message Date
Alexandre Belloni
322192640b ARM: at91/dt: qil_a9260: define crystals frequencies
Define Calao QIL-A9260 main and slow crystals frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:15 +02:00
Alexandre Belloni
90de7ccc81 ARM: at91/dt: tny_a9260: define crystals frequencies
Define Calao TNY-A9260 and TNY-A9G20 main and slow crystals frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:15 +02:00
Alexandre Belloni
f1e7861518 ARM: at91/dt: usb_a9260: define crystals frequencies
Define Calao USB-A9260, USB-A9G20 and USB-A9G20-LPW main and slow crystals
frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:14 +02:00
Alexandre Belloni
32cc703a23 ARM: at91/dt: foxg20: define crystals frequencies
Define Acme Systems srl Fox G20 main and slow crystals frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:14 +02:00
Alexandre Belloni
f48a833534 ARM: at91/dt: at91sam9g20ek: define crystals frequencies
Define at91sam9g20ek main and slow crystals frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:14 +02:00
Alexandre Belloni
20183110a8 ARM: at91: move at91sam9260 SoCs to the CCF
This patch removes the selection of AT91_USE_OLD_CLK when selecting at91sam9260
SoCs support. This will automatically enable COMMON_CLK_AT91 option and add
support for at91 common clk implementation.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:13 +02:00
Alexandre Belloni
09d773cea8 ARM: at91/dt: sam9g20: define clocks
Define the at91sam9g20 clocks that differ from at91sam9260 in the SoC dtsi file.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:13 +02:00
Alexandre Belloni
684b8fb5a0 ARM: at91/dt: sam9260: define clocks
Define the at91sam9260 clocks in the SoC dtsi file.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:13 +02:00
Alexandre Belloni
57b37ed519 ARM: at91: prepare common clk transition for sam9260
Enclose the sam9260 old clk registration in "#if defined(CONFIG_OLD_CLK_AT91)
 #endif"

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:12 +02:00
Alexandre Belloni
94788118ef ARM: at91/dt: at91rm9200ek: define crystals frequencies
Define at91rm9200ek main and slow crystals frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:12 +02:00
Alexandre Belloni
93af052da5 ARM: at91: move at91rm9200 SoC to the CCF
This patch removes the selection of AT91_USE_OLD_CLK when selecting at91rm9200
SoC support. This will automatically enable COMMON_CLK_AT91 option and add
support for at91 common clk implementation.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:11 +02:00
Alexandre Belloni
68580013ad ARM: at91/dt: rm9200: define clocks
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:11 +02:00
Alexandre Belloni
36c203f1ca ARM: at91: prepare common clk transition for rm9200
Enclose the rm9200 old clk registration in "#if defined(CONFIG_OLD_CLK_AT91)
 #endif"

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:11 +02:00
Alexandre Belloni
152f3003f0 ARM: at91/dt: ariag25: define crystals frequencies
Define Acme Systems Aria G25 board main and slow crystals frequencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 19:05:10 +02:00
Alexandre Belloni
ed0a3ff435 Documentation: dt: document all the atmel pmc compatibles
Documentation for atmel-pmc only list one compatible, add the remaining
compatible strings.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2014-07-09 19:05:10 +02:00
Linus Torvalds
191d385f25 f2fs bugfixes for 3.16
o fix normal and recovery path for fallocated regions
 o fix error case mishandling
 o recover renamed fsync inodes correctly
 o fix to get out of infinite loops in balance_dirty_pages
 o fix kernel NULL pointer error
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Merge tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs bugfixes from Jaegeuk Kim:
 "This includes a couple of bug fixes found by xfstests.  In addition,
  one critical bug was reported by Brian Chadwick, which is falling into
  the infinite loop in balance_dirty_pages.  And it turned out due to
  the IO merging policy in f2fs, which was newly merged in 3.16.

   - fix normal and recovery path for fallocated regions
   - fix error case mishandling
   - recover renamed fsync inodes correctly
   - fix to get out of infinite loops in balance_dirty_pages
   - fix kernel NULL pointer error"

* tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: avoid to access NULL pointer in issue_flush_thread
  f2fs: check bdi->dirty_exceeded when trying to skip data writes
  f2fs: do checkpoint for the renamed inode
  f2fs: release new entry page correctly in error path of f2fs_rename
  f2fs: fix error path in init_inode_metadata
  f2fs: check lower bound nid value in check_nid_range
  f2fs: remove unused variables in f2fs_sm_info
  f2fs: fix not to allocate unnecessary blocks during fallocate
  f2fs: recover fallocated data and its i_size together
  f2fs: fix to report newly allocate region as extent
2014-07-09 09:46:58 -07:00
Johan Hedberg
c072d546c2 Bluetooth: Fix incorrect clearing of SMP_FLAG_INITIATOR
When the SMP context is created all flags default to zero. To determine
that we are the initiators it's therefore best to simply change the flag
value when we know we're sending the first SMP PDU. Clearing the flag
when receiving a Pairing Request is not correct since the request may be
a response to a previous Security Request from us (for which we would
already have correctly set the flag). Same goes for receiving a Security
Request which may be coming after us already starting pairing by sending
a Pairing Request.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-09 18:23:06 +02:00
Johan Hedberg
e247605a62 Bluetooth: Fix forcing SMP just-works with no-bonding
Whether we bond or not should not have any impact on the user
interaction model. This patch removes an incorrect fall-back from
JUST_CFM to JUST_WORKS in case we're not bonding.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-09 18:23:06 +02:00
Johan Hedberg
2bcd4003b8 Bluetooth: Always confirm incoming SMP just-works requests
For incoming requests we want to let the user know that pairing is
happening since otherwise there could be access to MEDIUM security
services without any user interaction at all. Therefore, set the
selected method to JUST_CFM instead of JUST_WORKS and let it be
converted back to JUST_WORKS later if we are the initators.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-09 18:23:05 +02:00
Paul E. McKenney
1823172ab5 Merge branches 'doc.2014.07.08a', 'fixes.2014.07.09a', 'maintainers.2014.07.08b', 'nocbs.2014.07.07a' and 'torture.2014.07.07a' into HEAD
doc.2014.07.08a: Documentation updates.
fixes.2014.07.09a: Miscellaneous fixes.
maintainers.2014.07.08b: Maintainership updates.
nocbs.2014.07.07a: Callback-offloading fixes.
torture.2014.07.07a: Torture-test updates.
2014-07-09 09:16:54 -07:00
Pranith Kumar
b41d1b924d rcu: Fix a sparse warning in rcu_report_unblock_qs_rnp()
This commit annotates rcu_report_unblock_qs_rnp() in order to fix the
following sparse warning:

kernel/rcu/tree_plugin.h:990:13: warning: context imbalance in 'rcu_report_unblock_qs_rnp' - unexpected unlock

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:15:51 -07:00
Pranith Kumar
615e41c605 rcu: Fix a sparse warning in rcu_initiate_boost()
This commit annotates rcu_initiate_boost() fixes the following sparse
warning:

	kernel/rcu/tree_plugin.h:1494:13: warning: context imbalance in 'rcu_initiate_boost' - unexpected unlock

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:15:45 -07:00
Paul E. McKenney
406e3e5365 rcu: Fix __rcu_reclaim() to use true/false for bool
The __rcu_reclaim() function returned 0/1, which is not proper for a
function of type bool.  This commit therefore converts to false/true.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:15:32 -07:00
Paul E. McKenney
11992c703a rcu: Remove CONFIG_PROVE_RCU_DELAY
The CONFIG_PROVE_RCU_DELAY Kconfig parameter doesn't appear to be very
effective at finding race conditions, so this commit removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
[ paulmck: Remove definition and uses as noted by Paul Bolle. ]
2014-07-09 09:15:31 -07:00
Shan Wei
d860d40327 rcu: Use __this_cpu_read() instead of per_cpu_ptr()
The __this_cpu_read() function produces better code than does
per_cpu_ptr() on both ARM and x86.  For example, gcc (Ubuntu/Linaro
4.7.3-12ubuntu1) 4.7.3 produces the following:

ARMv7 per_cpu_ptr():

force_quiescent_state:
    mov    r3, sp    @,
    bic    r1, r3, #8128    @ tmp171,,
    ldr    r2, .L98    @ tmp169,
    bic    r1, r1, #63    @ tmp170, tmp171,
    ldr    r3, [r0, #220]    @ __ptr, rsp_6(D)->rda
    ldr    r1, [r1, #20]    @ D.35903_68->cpu, D.35903_68->cpu
    mov    r6, r0    @ rsp, rsp
    ldr    r2, [r2, r1, asl #2]    @ tmp173, __per_cpu_offset
    add    r3, r3, r2    @ tmp175, __ptr, tmp173
    ldr    r5, [r3, #12]    @ rnp_old, D.29162_13->mynode

ARMv7 __this_cpu_read():

force_quiescent_state:
    ldr    r3, [r0, #220]    @ rsp_7(D)->rda, rsp_7(D)->rda
    mov    r6, r0    @ rsp, rsp
    add    r3, r3, #12    @ __ptr, rsp_7(D)->rda,
    ldr    r5, [r2, r3]    @ rnp_old, *D.29176_13

Using gcc 4.8.2:

x86_64 per_cpu_ptr():

    movl %gs:cpu_number,%edx    # cpu_number, pscr_ret__
    movslq    %edx, %rdx    # pscr_ret__, pscr_ret__
    movq    __per_cpu_offset(,%rdx,8), %rdx    # __per_cpu_offset, tmp93
    movq    %rdi, %r13    # rsp, rsp
    movq    1000(%rdi), %rax    # rsp_9(D)->rda, __ptr
    movq    24(%rdx,%rax), %r12    # _15->mynode, rnp_old

x86_64 __this_cpu_read():

    movq    %rdi, %r13    # rsp, rsp
    movq    1000(%rdi), %rax    # rsp_9(D)->rda, rsp_9(D)->rda
    movq %gs:24(%rax),%r12    # _10->mynode, rnp_old

Because this change produces significant benefits for these two very
diverse architectures, this commit makes this change.

Signed-off-by: Shan Wei <davidshan@tencent.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:15:21 -07:00
Paul E. McKenney
bc1dce514e rcu: Don't use NMIs to dump other CPUs' stacks
Although NMI-based stack dumps are in principle more accurate, they are
also more likely to trigger deadlocks.  This commit therefore replaces
all uses of trigger_all_cpu_backtrace() with rcu_dump_cpu_stacks(), so
that the CPU detecting an RCU CPU stall does the stack dumping.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:15:04 -07:00
Paul E. McKenney
c0f489d2c6 rcu: Bind grace-period kthreads to non-NO_HZ_FULL CPUs
Binding the grace-period kthreads to the timekeeping CPU resulted in
significant performance decreases for some workloads.  For more detail,
see:

https://lkml.org/lkml/2014/6/3/395 for benchmark numbers

https://lkml.org/lkml/2014/6/4/218 for CPU statistics

It turns out that it is necessary to bind the grace-period kthreads
to the timekeeping CPU only when all but CPU 0 is a nohz_full CPU
on the one hand or if CONFIG_NO_HZ_FULL_SYSIDLE=y on the other.
In other cases, it suffices to bind the grace-period kthreads to the
set of non-nohz_full CPUs.

This commit therefore creates a tick_nohz_not_full_mask that is the
complement of tick_nohz_full_mask, and then binds the grace-period
kthread to the set of CPUs indicated by this new mask, which covers
the CONFIG_NO_HZ_FULL_SYSIDLE=n case.  The CONFIG_NO_HZ_FULL_SYSIDLE=y
case still binds the grace-period kthreads to the timekeeping CPU.
This commit also includes the tick_nohz_full_enabled() check suggested
by Frederic Weisbecker.

Reported-by: Jet Chen <jet.chen@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Created housekeeping_affine() and housekeeping_mask per
  fweisbec feedback. ]
2014-07-09 09:15:02 -07:00
Paul E. McKenney
abaa93d9e1 rcu: Simplify priority boosting by putting rt_mutex in rcu_node
RCU priority boosting currently checks for boosting via a pointer in
task_struct.  However, this is not needed: As Oleg noted, if the
rt_mutex is placed in the rcu_node instead of on the booster's stack,
the boostee can simply check it see if it owns the lock.  This commit
makes this change, shrinking task_struct by one pointer and the kernel
by thirteen lines.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09 09:15:01 -07:00
Pranith Kumar
48bd8e9b82 rcu: Check both root and current rcu_node when setting up future grace period
The rcu_start_future_gp() function checks the current rcu_node's ->gpnum
and ->completed twice, once without ACCESS_ONCE() and once with it.
Which is pointless because we hold that rcu_node's ->lock at that point.
The intent was to check the current rcu_node structure and the root
rcu_node structure, the latter locklessly with ACCESS_ONCE().  This
commit therefore makes that change.

The reason that it is safe to locklessly check the root rcu_nodes's
->gpnum and ->completed fields is that we hold the current rcu_node's
->lock, which constrains the root rcu_node's ability to change its
->gpnum and ->completed fields.  Of course, if there is a single rcu_node
structure, then rnp_root==rnp, and holding the lock prevents all changes.
If there is more than one rcu_node structure, then the code updates the
fields in the following order:

1.	Increment rnp_root->gpnum to start new grace period.
2.	Increment rnp->gpnum to initialize the current rcu_node,
	continuing initialization for the new grace period.
3.	Increment rnp_root->completed to end the current grace period.
4.	Increment rnp->completed to continue cleaning up after the
	old grace period.

So there are four possible combinations of relative values of these
four fields:

N   N   N   N:  RCU idle, new grace period must be initiated.
		Although rnp_root->gpnum might be incremented immediately
		after we check, that will just result in unnecessary work.
		The grace period already started, and we try to start it.

N+1 N   N   N:  RCU grace period just started.  No further change is
		possible because we hold rnp->lock, so the checks of
		rnp_root->gpnum and rnp_root->completed are stable.
		We know that our request for a future grace period will
		be seen during grace-period cleanup.

N+1 N   N+1 N:  RCU grace period is ongoing.  Because rnp->gpnum is
		different than rnp->completed, we won't even look at
		rnp_root->gpnum and rnp_root->completed, so the possible
		concurrent change to rnp_root->completed does not matter.
		We know that our request for a future grace period will
		be seen during grace-period cleanup, which cannot pass
		this rcu_node because we hold its ->lock.

N+1 N+1 N+1 N:  RCU grace period has ended, but not yet been cleaned up.
		Because rnp->gpnum is different than rnp->completed, we
		won't look at rnp_root->gpnum and rnp_root->completed, so
		the possible concurrent change to rnp_root->completed does
		not matter.  We know that our request for a future grace
		period will be seen during grace-period cleanup, which
		cannot pass this rcu_node because we hold its ->lock.

Therefore, despite initial appearances, the lockless check is safe.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
[ paulmck: Update comment to say why the lockless check is safe. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09 09:15:01 -07:00
Paul E. McKenney
dfeb9765ce rcu: Allow post-unlock reference for rt_mutex
The current approach to RCU priority boosting uses an rt_mutex strictly
for its priority-boosting side effects.  The rt_mutex_init_proxy_locked()
function is used by the booster to initialize the lock as held by the
boostee.  The booster then uses rt_mutex_lock() to acquire this rt_mutex,
which priority-boosts the boostee.  When the boostee reaches the end
of its outermost RCU read-side critical section, it checks a field in
its task structure to see whether it has been boosted, and, if so, uses
rt_mutex_unlock() to release the rt_mutex.  The booster can then go on
to boost the next task that is blocking the current RCU grace period.

But reasonable implementations of rt_mutex_unlock() might result in the
boostee referencing the rt_mutex's data after releasing it.  But the
booster might have re-initialized the rt_mutex between the time that the
boostee released it and the time that it later referenced it.  This is
clearly asking for trouble, so this commit introduces a completion that
forces the booster to wait until the boostee has completely finished with
the rt_mutex, thus avoiding the case where the booster is re-initializing
the rt_mutex before the last boostee's last reference to that rt_mutex.

This of course does introduce some overhead, but the priority-boosting
code paths are miles from any possible fastpath, and the overhead of
executing the completion will normally be quite small compared to the
overhead of priority boosting and deboosting, so this should be OK.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09 09:15:00 -07:00
Paul E. McKenney
1146edcbef rcu: Loosen __call_rcu()'s rcu_head alignment constraint
The m68k architecture aligns only to 16-bit boundaries, which can cause
the align-to-32-bits check in __call_rcu() to trigger.  Because there is
currently no known potential need for more than one low-order bit, this
commit loosens the check to 16-bit boundaries.

Reported-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:14:50 -07:00
Paul E. McKenney
a792563bd4 rcu: Eliminate read-modify-write ACCESS_ONCE() calls
RCU contains code of the following forms:

	ACCESS_ONCE(x)++;
	ACCESS_ONCE(x) += y;
	ACCESS_ONCE(x) -= y;

Now these constructs do operate correctly, but they really result in a
pair of volatile accesses, one to do the load and another to do the store.
This can be confusing, as the casual reader might well assume that (for
example) gcc might generate a memory-to-memory add instruction for each
of these three cases.  In fact, gcc will do no such thing.  Also, there
is a good chance that the kernel will move to separate load and store
variants of ACCESS_ONCE(), and constructs like the above could easily
confuse both people and scripts attempting to make that sort of change.
Finally, most of RCU's read-modify-write uses of ACCESS_ONCE() really
only need the store to be volatile, so that the read-modify-write form
might be misleading.

This commit therefore changes the above forms in RCU so that each instance
of ACCESS_ONCE() either does a load or a store, but not both.  In a few
cases, ACCESS_ONCE() was not critical, for example, for maintaining
statisitics.  In these cases, ACCESS_ONCE() has been dispensed with
entirely.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09 09:14:49 -07:00
Paul E. McKenney
4da117cfa7 rcu: Remove redundant ACCESS_ONCE() from tick_do_timer_cpu
In kernels built with CONFIG_NO_HZ_FULL, tick_do_timer_cpu is constant
once boot completes.  Thus, there is no need to wrap it in ACCESS_ONCE()
in code that is built only when CONFIG_NO_HZ_FULL.  This commit therefore
removes the redundant ACCESS_ONCE().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:14:35 -07:00
Fabian Frederick
b4426b49c6 rcu: Make rcu node arrays static const char * const
Those two arrays are being passed to lockdep_init_map(), which expects
const char *, and are stored in lockdep_map the same way.

Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09 09:14:34 -07:00
Paul E. McKenney
c41247e1d4 signal: Explain local_irq_save() call
The explicit local_irq_save() in __lock_task_sighand() is needed to avoid
a potential deadlock condition, as noted in a841796f11 (signal:
align __lock_task_sighand() irq disabling and RCU).  However, someone
reading the code might be forgiven for concluding that this separate
local_irq_save() was completely unnecessary.  This commit therefore adds
a comment referencing the shiny new block comment on rcu_read_unlock().

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:14:33 -07:00
Paul E. McKenney
ab74fdfd4e rcu: Handle obsolete references to TINY_PREEMPT_RCU
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:14:17 -07:00
Paul E. McKenney
f27bc4873f rcu: Document deadlock-avoidance information for rcu_read_unlock()
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09 09:14:07 -07:00
James Hogan
c2d2c21bff KVM: MIPS: Document MIPS specifics of KVM API.
Document the MIPS specific parts of the KVM API, including:
 - The layout of the kvm_regs structure.
 - The interrupt number passed to KVM_INTERRUPT.
 - The registers supported by the KVM_{GET,SET}_ONE_REG interface, and
   the encoding of those register ids.
 - That KVM_INTERRUPT and KVM_GET_REG_LIST are supported on MIPS.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:59 +02:00
James Hogan
bf5590f379 KVM: Reformat KVM_SET_ONE_REG register documentation
Some of the MIPS registers that can be accessed with the
KVM_{GET,SET}_ONE_REG interface have fairly long names, so widen the
Register column of the table in the KVM_SET_ONE_REG documentation to
allow them to fit.

Tabs in the table are replaced with spaces at the same time for
consistency.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:58 +02:00
James Hogan
572e09290a KVM: Document KVM_SET_SIGNAL_MASK as universal
KVM_SET_SIGNAL_MASK is implemented in generic code and isn't x86
specific, so document it as being applicable for all architectures.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:58 +02:00
Nadav Amit
98eff52ab5 KVM: x86: Fix lapic.c debug prints
In two cases lapic.c does not use the apic_debug macro correctly. This patch
fixes them.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:57 +02:00
Tomasz Grabiec
0d3da0d26e KVM: x86: fix TSC matching
I've observed kvmclock being marked as unstable on a modern
single-socket system with a stable TSC and qemu-1.6.2 or qemu-2.0.0.

The culprit was failure in TSC matching because of overflow of
kvm_arch::nr_vcpus_matched_tsc in case there were multiple TSC writes
in a single synchronization cycle.

Turns out that qemu does multiple TSC writes during init, below is the
evidence of that (qemu-2.0.0):

The first one:

 0xffffffffa08ff2b4 : vmx_write_tsc_offset+0xa4/0xb0 [kvm_intel]
 0xffffffffa04c9c05 : kvm_write_tsc+0x1a5/0x360 [kvm]
 0xffffffffa04cfd6b : kvm_arch_vcpu_postcreate+0x4b/0x80 [kvm]
 0xffffffffa04b8188 : kvm_vm_ioctl+0x418/0x750 [kvm]

The second one:

 0xffffffffa08ff2b4 : vmx_write_tsc_offset+0xa4/0xb0 [kvm_intel]
 0xffffffffa04c9c05 : kvm_write_tsc+0x1a5/0x360 [kvm]
 0xffffffffa090610d : vmx_set_msr+0x29d/0x350 [kvm_intel]
 0xffffffffa04be83b : do_set_msr+0x3b/0x60 [kvm]
 0xffffffffa04c10a8 : msr_io+0xc8/0x160 [kvm]
 0xffffffffa04caeb6 : kvm_arch_vcpu_ioctl+0xc86/0x1060 [kvm]
 0xffffffffa04b6797 : kvm_vcpu_ioctl+0xc7/0x5a0 [kvm]

 #0  kvm_vcpu_ioctl at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1780
 #1  kvm_put_msrs at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1270
 #2  kvm_arch_put_registers at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1909
 #3  kvm_cpu_synchronize_post_init at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1641
 #4  cpu_synchronize_post_init at /build/buildd/qemu-2.0.0+dfsg/include/sysemu/kvm.h:330
 #5  cpu_synchronize_all_post_init () at /build/buildd/qemu-2.0.0+dfsg/cpus.c:521
 #6  main at /build/buildd/qemu-2.0.0+dfsg/vl.c:4390

The third one:

 0xffffffffa08ff2b4 : vmx_write_tsc_offset+0xa4/0xb0 [kvm_intel]
 0xffffffffa04c9c05 : kvm_write_tsc+0x1a5/0x360 [kvm]
 0xffffffffa090610d : vmx_set_msr+0x29d/0x350 [kvm_intel]
 0xffffffffa04be83b : do_set_msr+0x3b/0x60 [kvm]
 0xffffffffa04c10a8 : msr_io+0xc8/0x160 [kvm]
 0xffffffffa04caeb6 : kvm_arch_vcpu_ioctl+0xc86/0x1060 [kvm]
 0xffffffffa04b6797 : kvm_vcpu_ioctl+0xc7/0x5a0 [kvm]

 #0  kvm_vcpu_ioctl at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1780
 #1  kvm_put_msrs  at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1270
 #2  kvm_arch_put_registers  at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1909
 #3  kvm_cpu_synchronize_post_reset  at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1635
 #4  cpu_synchronize_post_reset  at /build/buildd/qemu-2.0.0+dfsg/include/sysemu/kvm.h:323
 #5  cpu_synchronize_all_post_reset () at /build/buildd/qemu-2.0.0+dfsg/cpus.c:512
 #6  main  at /build/buildd/qemu-2.0.0+dfsg/vl.c:4482

The fix is to count each vCPU only once when matched, so that
nr_vcpus_matched_tsc holds the size of the matched set. This is
achieved by reusing generation counters. Every vCPU with
this_tsc_generation == cur_tsc_generation is in the matched set. The
match set is cleared by setting cur_tsc_generation to a value which no
other vCPU is set to (by incrementing it).

I needed to bump up the counter size form u8 to u64 to ensure it never
overflows. Otherwise in cases TSC is not written the same number of
times on each vCPU the counter could overflow and incorrectly indicate
some vCPUs as being in the matched set. This scenario seems unlikely
but I'm not sure if it can be disregarded.

Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:57 +02:00
Jan Kiszka
6cbc5f5a80 KVM: nSVM: Set correct port for IOIO interception evaluation
Obtaining the port number from DX is bogus as a) there are immediate
port accesses and b) user space may have changed the register content
while processing the PIO access. Forward the correct value from the
instruction emulator instead.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:56 +02:00
Jan Kiszka
6493f1574e KVM: nSVM: Fix IOIO size reported on emulation
The access size of an in/ins is reported in dst_bytes, and that of
out/outs in src_bytes.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:56 +02:00
Jan Kiszka
9bf418335e KVM: nSVM: Fix IOIO bitmap evaluation
First, kvm_read_guest returns 0 on success. And then we need to take the
access size into account when testing the bitmap: intercept if any of
bits corresponding to the access is set.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:55 +02:00
Jan Kiszka
62baf44cad KVM: nSVM: Do not report CLTS via SVM_EXIT_WRITE_CR0 to L1
CLTS only changes TS which is not monitored by selected CR0
interception. So skip any attempt to translate WRITE_CR0 to
CR0_SEL_WRITE for this instruction.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09 18:09:55 +02:00
Nicolas Ferre
ad7c56aa2d ARM: at91/dt: add NAND + DMA property for at91sam9rl
Add the "atmel,nand-has-dma" property to NAND node

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2014-07-09 18:02:47 +02:00
Nicolas Ferre
4cd9292926 ARM: at91/dt: add DMA controller node to at91sam9rl
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2014-07-09 18:02:46 +02:00
Bo Shen
38324358c5 ARM: at91: at91sam9n12ek: switch sound to CCF
As the at91sam9n12ek has switch to CCF, so add clock for wm8904

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Reviwed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 18:02:46 +02:00
Bo Shen
18f44d7bd6 ARM: at91: sama5d3xek: switch sound to CCF
As the sama5d3xek board has switch to CCF, so add clock for wm8904

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Reviwed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-07-09 18:02:45 +02:00