Paul E. McKenney [Fri, 15 Jan 2016 17:30:42 +0000 (09:30 -0800)]
documentation: Distinguish between local and global transitivity
The introduction of smp_load_acquire() and smp_store_release() had
the side effect of introducing a weaker notion of transitivity:
The transitivity of full smp_mb() barriers is global, but that
of smp_store_release()/smp_load_acquire() chains is local. This
commit therefore introduces the notion of local transitivity and
gives an example.
Reported-by: Peter Zijlstra <peterz@infradead.org> Reported-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 14 Jan 2016 22:17:04 +0000 (14:17 -0800)]
documentation: Subsequent writes ordered by rcu_dereference()
The current memory-barriers.txt does not address the possibility of
a write to a dereferenced pointer. This should be rare, but when it
happens, we need that write -not- to be clobbered by the initialization.
This commit therefore adds an example showing a data dependency ordering
a later data-dependent write.
Reported-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 14 Jan 2016 22:01:34 +0000 (14:01 -0800)]
documentation: Remove obsolete reference to RCU-protected indexes
Commit #1ebee8017d84 (rcu: Eliminate array-index-based RCU primitives)
eliminated the primitives supporting RCU-protected array indexes, but
failed to update Documentation/memory-barriers.txt accordingly. This
commit therefore removes the discussion of RCU-protected array indexes.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 13 Jan 2016 21:57:54 +0000 (13:57 -0800)]
rcu: Make cond_resched_rcu_qs() supply RCU-sched expedited QS
Although cond_resched_rcu_qs() supplies quiescent states to all flavors
of normal RCU grace periods, it does nothing for expedited RCU-sched
grace periods. This commit therefore adds a check for a need for a
quiescent state from the current CPU by an expedited RCU-sched grace
period, and invokes rcu_sched_qs() to supply that quiescent state if so.
Note that the check is racy in that we might be migrated to some other
CPU just after checking the per-CPU variable. This is OK because the
act of migration will do a context switch, which will supply the needed
quiescent state. The only downside is that we might do an unnecessary
call to rcu_sched_qs(), but the probability is low and the overhead
is small.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 13 Jan 2016 18:52:35 +0000 (10:52 -0800)]
rcu: Make expedited RCU-preempt stall warnings count accurately
Currently, synchronize_sched_expedited_wait() simply sets the ndetected
variable to the rcu_print_task_exp_stall() return value. This means
that if the last rcu_node structure has no stalled tasks, record of
any stalled tasks in previous rcu_node structures is lost, which can
in turn result in failure to dump out the blocking rcu_node structures.
Or could, had the test been correct.
This commit therefore adds the return value of rcu_print_task_exp_stall()
to ndetected and corrects the later test for ndetected.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 13 Jan 2016 01:26:35 +0000 (17:26 -0800)]
rcutorture: Print measure of batching efficiency
This commit adds a line giving the number of grace periods, the number
of batches, and the ratio. The larger the ratio, the greater the
batching efficiency.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 12 Jan 2016 16:33:37 +0000 (08:33 -0800)]
rcu: Make expedited RCU-sched grace period immediately detect idle
Currently, sync_sched_exp_handler() will force a reschedule unless
this CPU has already checked in or unless a reschedule has already
been called for. This is clearly wasteful if sync_sched_exp_handler()
interrupted an idle CPU, so this commit immediately reports the
quiescent state in that case.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 12 Jan 2016 00:29:29 +0000 (16:29 -0800)]
rcu: Force boolean subscript for expedited stall warnings
The cpu_online() function can return values other than 0 and 1, which
can result in subscript overflow when applied to a two-element array.
This commit allows for this behavior by using "!!" on the return value
from cpu_online() when used as a subscript.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Document unique-name limitation for DEFINE_STATIC_SRCU()
SRCU uses per-CPU variables, and DEFINE_STATIC_SRCU() uses a static
per-CPU variable. However, per-CPU variables have significant
restrictions, for example, names of per-CPU variables must be globally
unique, even if declared static. These restrictions carry over to
DEFINE_STATIC_SRCU(), and this commit therefore documents these
restrictions.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: kbuild test robot <fengguang.wu@intel.com> Suggested-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Tejun Heo <tj@kernel.org>
Paul Gortmaker [Fri, 8 Jan 2016 00:05:19 +0000 (19:05 -0500)]
rcu: Make rcu/tiny_plugin.h explicitly non-modular
The Kconfig currently controlling compilation of this code is:
init/Kconfig:config TINY_RCU
init/Kconfig: bool
...meaning that it currently is not being built as a module by anyone.
Lets remove the modular code that is essentially orphaned, so that
when reading the code there is no doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit. We could
consider moving this to an earlier initcall (subsys?) if desired.
We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.
Cc: Josh Triplett <josh@joshtriplett.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit fixes a couple of "Compiler Barrier" section references to
be "COMPILER BARRIER". This makes it easier to find the section in
the usual text editors.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
irq_common_data::state_use_accessors is not designed for public use.
Therefore make it private so that people who write code accessing it
directly will get blamed by sparse. Also #undef the macro
__irqd_to_state after used in header files, so that the macro can't be
misused.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Boqun Feng [Tue, 29 Dec 2015 04:18:47 +0000 (12:18 +0800)]
RCU: Privatize rcu_node::lock
In patch:
"rcu: Add transitivity to remaining rcu_node ->lock acquisitions"
All locking operations on rcu_node::lock are replaced with the wrappers
because of the need of transitivity, which indicates we should never
write code using LOCK primitives alone(i.e. without a proper barrier
following) on rcu_node::lock outside those wrappers. We could detect
this kind of misuses on rcu_node::lock in the future by adding __private
modifier on rcu_node::lock.
To privatize rcu_node::lock, unlock wrappers are also needed. Replacing
spinlock unlocks with these wrappers not only privatizes rcu_node::lock
but also makes it easier to figure out critical sections of rcu_node.
This patch adds __private modifier to rcu_node::lock and makes every
access to it wrapped by ACCESS_PRIVATE(). Besides, unlock wrappers are
added and raw_spin_unlock(&rnp->lock) and its friends are replaced with
those wrappers.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Boqun Feng [Tue, 29 Dec 2015 04:18:46 +0000 (12:18 +0800)]
sparse: Add __private to privatize members of structs
In C programming language, we don't have a easy way to privatize a
member of a structure. However in kernel, sometimes there is a need to
privatize a member in case of potential bugs or misuses.
Fortunately, the noderef attribute of sparse is a way to privatize a
member, as by defining a member as noderef, the address-of operator on
the member will produce a noderef pointer to that member, and if anyone
wants to dereference that kind of pointers to read or modify the member,
sparse will yell.
Based on this, __private modifier and related operation ACCESS_PRIVATE()
are introduced, which could help detect undesigned public uses of
private members of structs. Here is an example of sparse's output if it
detect an undersigned public use:
Chen Gang [Sat, 26 Dec 2015 13:41:44 +0000 (21:41 +0800)]
rcu: Remove useless rcu_data_p when !PREEMPT_RCU
The related warning from gcc 6.0:
In file included from kernel/rcu/tree.c:4630:0:
kernel/rcu/tree_plugin.h:810:40: warning: ‘rcu_data_p’ defined but not used [-Wunused-const-variable]
static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;
^~~~~~~~~~
Also remove always redundant rcu_data_p in tree.c.
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Awaken grace-period kthread if too long since FQS
Recent kernels can fail to awaken the grace-period kthread for
quiescent-state forcing. This commit is a crude hack that does
a wakeup if a scheduling-clock interrupt sees that it has been
too long since force-quiescent-state (FQS) processing.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Make FQS schedule advance only if FQS happened
Currently, the force-quiescent-state (FQS) code in rcu_gp_kthread() can
advance the next FQS even if one was not executed last time. This can
happen due timeout-duration uncertainty. This commit therefore avoids
advancing the FQS schedule unless an FQS was just executed. In the
corner case where an FQS was not executed, but is due now, the code does
a one-jiffy wait.
This change prepares for kthread kicking.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 12 Jan 2016 21:43:30 +0000 (13:43 -0800)]
rcutorture: Expedited-GP batch progress access to torturing
This commit provides rcu_exp_batches_completed() and
rcu_exp_batches_completed_sched() functions to allow torture-test modules
to check how many expedited grace period batches have completed.
These are analogous to the existing rcu_batches_completed(),
rcu_batches_completed_bh(), and rcu_batches_completed_sched() functions.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, rcu_torture_writer() checks only for rcu_gp_is_expedited()
when deciding whether or not to do dynamic control of RCU expediting.
This means that if rcupdate.rcu_normal is specified, rcu_torture_writer()
will attempt to dynamically control RCU expediting, but will nonetheless
only test normal RCU grace periods. This commit therefore adds a check
for !rcu_gp_is_normal(), and prints a message and desists from testing
dynamic control of RCU expediting when doing so is futile.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The "Disabled dynamic grace-period expediting" console message is
currently printed unconditionally. This commit causes it to be
output only when it is impossible to switch between normal and
expedited grace periods, which was the original intent.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 31 Dec 2015 16:48:36 +0000 (08:48 -0800)]
rcu: Awaken grace-period kthread when stalled
Recent kernels can fail to awaken the grace-period kthread for
quiescent-state forcing. This commit is a crude hack that does
a wakeup any time a stall is detected.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 30 Dec 2015 00:23:18 +0000 (16:23 -0800)]
documentation: Fix control dependency and identical stores
The summary of the "CONTROL DEPENDENCIES" section incorrectly states that
barrier() may be used to prevent compiler reordering when more than one
leg of the control-dependent "if" statement start with identical stores.
This is incorrect at high optimization levels. This commit therefore
updates the summary to match the detailed description.
Reported by: Jianyu Zhan <nasa4836@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Sun, 13 Dec 2015 16:57:10 +0000 (08:57 -0800)]
rcu: Set rdp->gpwrap when CPU is idle
Commit #e3663b1024d1 ("rcu: Handle gpnum/completed wrap while dyntick
idle") sets rdp->gpwrap on the wrong side of the "if" statement in
dyntick_save_progress_counter(), that is, it sets it when the CPU is
not idle instead of when it is idle. Of course, if the CPU is not idle,
its rdp->gpnum won't be lagging beind the global rsp->gpnum, which means
that rdp->gpwrap will never be set.
This commit therefore moves this code to the proper leg of that "if"
statement. This change means that the "else" cause is just "return 0"
and the "then" clause ends with "return 1", so also move the "return 0"
to follow the "if", dropping the "else" clause.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Sat, 12 Dec 2015 00:18:22 +0000 (16:18 -0800)]
documentation: Add real-time requirements from CPU-bound workloads
This commit records RCU's responsibility to avoid degrading latencies
of CPUs running tight loops within properly configured workloads,
both in kernel and in userspace.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Fri, 11 Dec 2015 21:48:43 +0000 (13:48 -0800)]
rcu: Stop treating in-kernel CPU-bound workloads as errors
Commit 4a81e8328d379 ("Reduce overhead of cond_resched() checks for RCU")
handles the error case where a nohz_full loops indefinitely in the kernel
with the scheduling-clock interrupt disabled. However, this handling
includes IPIing the CPU running the offending loop, which is not what
we want for real-time workloads. And there are starting to be real-time
CPU-bound in-kernel workloads, and these must be handled without IPIing
the CPU, at least not in the common case. Therefore, this situation can
no longer be dismissed as an error case.
This commit therefore splits the handling out, so that the setting of
bits in the per-CPU rcu_sched_qs_mask variable is done relatively early,
but if the problem persists, resched_cpu() is eventually used to IPI the
CPU containing the offending loop. Assuming that in-kernel CPU-bound
loops used by real-time tasks contain frequent calls cond_resched_rcu_qs()
(as in more than once per few tens of milliseconds), the real-time tasks
will never be IPIed.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org>
Paul E. McKenney [Thu, 10 Dec 2015 17:59:43 +0000 (09:59 -0800)]
rcu: Update rcu_report_qs_rsp() comment
The header comment for rcu_report_qs_rsp() was obsolete, dating well
before the advent of RCU grace-period kthreads. This commit therefore
brings this comment back into alignment with current reality.
Reported-by: Lihao Liang <lihao.liang@cs.ox.ac.uk> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 10 Dec 2015 00:10:23 +0000 (16:10 -0800)]
rcutorture: Check for self-detected stalls
The current scripts parse console output only for cases where one CPU
detect a stall on some other CPU or task. This commit therefore adds
checks for self-detected stalls.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, an error-free run produces an empty console.log.diags file.
This can be annoying when using "vi */console.log.diags" to see a full
summary of the errors. This commit therefore removes any empty files
during the analysis process.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Linus Torvalds [Sun, 24 Jan 2016 20:50:56 +0000 (12:50 -0800)]
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for MIPS for 4.5 plus some 4.4 fixes.
The executive summary:
- ATH79 platform improvments, use DT bindings for the ATH79 USB PHY.
- Avoid useless rebuilds for zboot.
- jz4780: Add NEMC, BCH and NAND device tree nodes
- Initial support for the MicroChip's DT platform. As all the device
drivers are missing this is still of limited use.
- Some Loongson3 cleanups.
- The unavoidable whitespace polishing.
- Reduce clock skew when synchronizing the CPU cycle counters on CPU
startup.
- Add MIPS R6 fixes.
- Lots of cleanups across arch/mips as fallout from KVM.
- Lots of minor fixes and changes for IEEE 754-2008 support to the
FPU emulator / fp-assist software.
- Minor Ralink, BCM47xx and bcm963xx platform support improvments.
- Support SMP on BCM63168"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (84 commits)
MIPS: zboot: Add support for serial debug using the PROM
MIPS: zboot: Avoid useless rebuilds
MIPS: BMIPS: Enable ARCH_WANT_OPTIONAL_GPIOLIB
MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function
MIPS: bcm963xx: Update bcm_tag field image_sequence
MIPS: bcm963xx: Move extended flash address to bcm_tag header file
MIPS: bcm963xx: Move Broadcom BCM963xx image tag data structure
MIPS: bcm63xx: nvram: Use nvram structure definition from header file
MIPS: bcm963xx: Add Broadcom BCM963xx board nvram data structure
MAINTAINERS: Add KVM for MIPS entry
MIPS: KVM: Add missing newline to kvm_err()
MIPS: Move KVM specific opcodes into asm/inst.h
MIPS: KVM: Use cacheops.h definitions
MIPS: Break down cacheops.h definitions
MIPS: Use EXCCODE_ constants with set_except_vector()
MIPS: Update trap codes
MIPS: Move Cause.ExcCode trap codes to mipsregs.h
MIPS: KVM: Make kvm_mips_{init,exit}() static
MIPS: KVM: Refactor added offsetof()s
MIPS: KVM: Convert EXPORT_SYMBOL to _GPL
...
Linus Torvalds [Sun, 24 Jan 2016 20:45:35 +0000 (12:45 -0800)]
Merge tag 'platform-drivers-x86-v4.5-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86
Pull x86 platform driver updates from Darren Hart:
"Emergency travel prevented me from completing my final testing on this
until today. Nothing here that couldn't wait until RC1 fixes, but I
thought it best to get it out sooner rather than later as it does
contain a build warning fix.
Summary:
A build warning fix, MAINTAINERS cleanup, and a new DMI quirk:
ideapad-laptop:
- Add Lenovo Yoga 700 to no_hw_rfkill dmi list
MAINTAINERS:
- Combine multiple telemetry entries
intel_telemetry_debugfs:
- Fix unused warnings in telemetry debugfs"
* tag 'platform-drivers-x86-v4.5-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list
MAINTAINERS: Combine multiple telemetry entries
intel_telemetry_debugfs: Fix unused warnings in telemetry debugfs
Linus Torvalds [Sun, 24 Jan 2016 20:43:06 +0000 (12:43 -0800)]
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal management updates from Zhang Rui:
"The top merge commit was re-generated yesterday because two topic
branches were dropped from this pull request in the last minute due to
some unaddressed comments. All the other material has been in
linux-next for quite a while.
Specifics:
- Enhance thermal core to handle unexpected device cooling states
after fresh boot and system resume. From Zhang Rui and Chen Yu.
- Several fixes and cleanups on Rockchip and RCAR thermal drivers.
From Caesar Wang and Kuninori Morimoto.
- Add Broxton support for Intel processor thermal reporting device
driver. From Amy Wiles"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal: trip_point_temp_store() calls thermal_zone_device_update()
thermal: rcar: rcar_thermal_get_temp() return error if strange temp
thermal: rcar: check irq possibility in rcar_thermal_irq_xxx()
thermal: rcar: check every rcar_thermal_update_temp() return value
thermal: rcar: move rcar_thermal_dt_ids to upside
thermal: rockchip: Support the RK3399 SoCs in thermal driver
thermal: rockchip: Support the RK3228 SoCs in thermal driver
dt-bindings: rockchip-thermal: Support the RK3228/RK3399 SoCs compatible
thermal: rockchip: fix a trivial typo
Thermal: Enable Broxton SoC thermal reporting device
thermal: constify pch_dev_ops structure
Thermal: do thermal zone update after a cooling device registered
Thermal: handle thermal zone device properly during system sleep
Thermal: initialize thermal zone device correctly
Linus Torvalds [Sun, 24 Jan 2016 20:39:09 +0000 (12:39 -0800)]
Merge tag 'for-linus-4.5-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
Pull 9p updates from Eric Van Hensbergen:
"Sorry for the last minute pull request, there's was a change that
didn't get pulled into for-next until two weeks ago and I wanted to
give it some bake time.
Summary:
Rework and error handling fixes, primarily in the fscatch and fd
transports"
* tag 'for-linus-4.5-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
fs/9p: use fscache mutex rather than spinlock
9p: trans_fd, bail out if recv fcall if missing
9p: trans_fd, read rework to use p9_parse_header
net/9p: Add device name details on error
Linus Torvalds [Sun, 24 Jan 2016 20:34:13 +0000 (12:34 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
"The two main changes are aio support in CephFS, and a series that
fixes several issues in the authentication key timeout/renewal code.
On top of that are a variety of cleanups and minor bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: remove outdated comment
libceph: kill off ceph_x_ticket_handler::validity
libceph: invalidate AUTH in addition to a service ticket
libceph: fix authorizer invalidation, take 2
libceph: clear messenger auth_retry flag if we fault
libceph: fix ceph_msg_revoke()
libceph: use list_for_each_entry_safe
ceph: use i_size_{read,write} to get/set i_size
ceph: re-send AIO write request when getting -EOLDSNAP error
ceph: Asynchronous IO support
ceph: Avoid to propagate the invalid page point
ceph: fix double page_unlock() in page_mkwrite()
rbd: delete an unnecessary check before rbd_dev_destroy()
libceph: use list_next_entry instead of list_entry_next
ceph: ceph_frag_contains_value can be boolean
ceph: remove unused functions in ceph_frag.h
Linus Torvalds [Sun, 24 Jan 2016 20:31:12 +0000 (12:31 -0800)]
Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull SMB3 fixes from Steve French:
"A collection of CIFS/SMB3 fixes.
It includes a couple bug fixes, a few for improved debugging of
cifs.ko and some improvements to the way cifs does key generation.
I do have some additional bug fixes I expect in the next week or two
(to address a problem found by xfstest, and some fixes for SMB3.11
dialect, and a couple patches that just came in yesterday that I am
reviewing)"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
cifs_dbg() outputs an uninitialized buffer in cifs_readdir()
cifs: fix race between call_async() and reconnect()
Prepare for encryption support (first part). Add decryption and encryption key generation. Thanks to Metze for helping with this.
cifs: Allow using O_DIRECT with cache=loose
cifs: Make echo interval tunable
cifs: Check uniqueid for SMB2+ and return -ESTALE if necessary
Print IP address of unresponsive server
cifs: Ratelimit kernel log messages
Josh Boyer [Sun, 24 Jan 2016 15:46:42 +0000 (10:46 -0500)]
ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list
Like the Yoga 900 models the Lenovo Yoga 700 does not have a
hw rfkill switch, and trying to read the hw rfkill switch through the
ideapad module causes it to always reported blocking breaking wifi.
This commit adds the Lenovo Yoga 700 to the no_hw_rfkill dmi list, fixing
the wifi breakage.
If we detect that there is nothing to do just set the flag and do not
check if it was already set before. Races really do not matter. If the
flag is set by any code then the shepherd will start dealing with the
situation and reenable the vmstat workers when necessary again.
Since commit 0eb77e988032 ("vmstat: make vmstat_updater deferrable again
and shut down on idle") quiet_vmstat might update cpu_stat_off and mark
a particular cpu to be handled by vmstat_shepherd. This might trigger a
VM_BUG_ON in vmstat_update because the work item might have been
sleeping during the idle period and see the cpu_stat_off updated after
the wake up. The VM_BUG_ON is therefore misleading and no more
appropriate. Moreover it doesn't really suite any protection from real
bugs because vmstat_shepherd will simply reschedule the vmstat_work
anytime it sees a particular cpu set or vmstat_update would do the same
from the worker context directly. Even when the two would race the
result wouldn't be incorrect as the counters update is fully idempotent.
Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Christoph Lameter <cl@linux.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alban Bedel [Thu, 10 Dec 2015 09:57:20 +0000 (10:57 +0100)]
MIPS: zboot: Avoid useless rebuilds
Add dummy.o to the targets list, and fill targets automatically from
$(vmlinuzobjs) to avoid having to maintain two lists.
When building with XZ compression copy ashldi3.c to the build
directory to use a different object file for the kernel and zboot.
Without this the same object file need to be build with different
flags which cause a rebuild at every run.
Signed-off-by: Alban Bedel <albeu@free.fr> Cc: linux-mips@linux-mips.org Cc: Alex Smith <alex.smith@imgtec.com> Cc: Wu Zhangjin <wuzhangjin@gmail.com> Cc: Andrew Bresticker <abrestic@chromium.org> Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11810/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Simon Arlott [Sun, 13 Dec 2015 22:47:55 +0000 (22:47 +0000)]
MIPS: bcm963xx: Move extended flash address to bcm_tag header file
The extended flash address needs to be subtracted from bcm_tag flash
image offsets. Move this value to the bcm_tag header file.
Renamed define name to consistently use bcm963xx for flash layout
which should be considered a property of the board and not the SoC
(i.e. bcm63xx could theoretically be used on a board without CFE
or any flash).
Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Jonas Gorski <jogo@openwrt.org> Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org> Cc: MIPS Mailing List <linux-mips@linux-mips.org> Cc: MTD Maling List <linux-mtd@lists.infradead.org>
Patchwork: https://patchwork.linux-mips.org/patch/11833/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Simon Arlott [Sun, 13 Dec 2015 22:45:30 +0000 (22:45 +0000)]
MIPS: bcm963xx: Add Broadcom BCM963xx board nvram data structure
Broadcom BCM963xx boards have multiple nvram variants across different
SoCs with additional checksum fields added whenever the size of the
nvram was extended.
Add this structure as a header file so that multiple drivers can use it.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Jonas Gorski <jogo@openwrt.org> Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org> Cc: MIPS Mailing List <linux-mips@linux-mips.org> Cc: MTD Maling List <linux-mtd@lists.infradead.org>
Patchwork: https://patchwork.linux-mips.org/patch/11830/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Linus Torvalds [Sun, 24 Jan 2016 02:45:06 +0000 (18:45 -0800)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma
Pull rdma updates from Doug Ledford:
"Initial roundup of 4.5 merge window patches
- Remove usage of ib_query_device and instead store attributes in
ib_device struct
- Move iopoll out of block and into lib, rename to irqpoll, and use
in several places in the rdma stack as our new completion queue
polling library mechanism. Update the other block drivers that
already used iopoll to use the new mechanism too.
- Replace the per-entry GID table locks with a single GID table lock
- IPoIB multicast cleanup
- Cleanups to the IB MR facility
- Add support for 64bit extended IB counters
- Fix for netlink oops while parsing RDMA nl messages
- Add support for remote invalidate to the iSER driver (pushed
through the RDMA tree due to dependencies, acknowledged by nab)
- Update to NFSoRDMA (pushed through the RDMA tree due to
dependencies, acknowledged by Bruce)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (169 commits)
IB/mlx5: Unify CQ create flags check
IB/mlx5: Expose Raw Packet QP to user space consumers
{IB, net}/mlx5: Move the modify QP operation table to mlx5_ib
IB/mlx5: Support setting Ethernet priority for Raw Packet QPs
IB/mlx5: Add Raw Packet QP query functionality
IB/mlx5: Add create and destroy functionality for Raw Packet QP
IB/mlx5: Refactor mlx5_ib_qp to accommodate other QP types
IB/mlx5: Allocate a Transport Domain for each ucontext
net/mlx5_core: Warn on unsupported events of QP/RQ/SQ
net/mlx5_core: Add RQ and SQ event handling
net/mlx5_core: Export transport objects
IB/mlx5: Expose CQE version to user-space
IB/mlx5: Add CQE version 1 support to user QPs and SRQs
IB/mlx5: Fix data validation in mlx5_ib_alloc_ucontext
IB/sa: Fix netlink local service GFP crash
IB/srpt: Remove redundant wc array
IB/qib: Improve ipoib UD performance
IB/mlx4: Advertise RoCE v2 support
IB/mlx4: Create and use another QP1 for RoCEv2
IB/mlx4: Enable send of RoCE QP1 packets with IP/UDP headers
...
James Hogan [Wed, 16 Dec 2015 23:49:38 +0000 (23:49 +0000)]
MIPS: Move KVM specific opcodes into asm/inst.h
The header arch/mips/kvm/opcode.h defines a few extra opcodes which
aren't in arch/mips/include/uapi/asm/inst.h. There's nothing KVM
specific about them, so lets move them into inst.h where they belong and
delete the header.
Note that mfmcz_op is renamed to mfmc0_op to match the instruction set
manual, and wait_op was already added to inst.h in commit b0a3eae2b943
("MIPS: inst.h: define COP0 wait op"), merged in v3.16-rc1.
James Hogan [Wed, 16 Dec 2015 23:49:37 +0000 (23:49 +0000)]
MIPS: KVM: Use cacheops.h definitions
Drop the custom cache operation code definitions used by KVM for
emulating guest CACHE instructions, and switch to use the existing
definitions in <asm/cacheops.h>.
James Hogan [Wed, 16 Dec 2015 23:49:36 +0000 (23:49 +0000)]
MIPS: Break down cacheops.h definitions
Most of the cache op codes defined in cacheops.h are split into a 2-bit
cache identifier, and a 3-bit cache op code which does largely the same
thing semantically regardless of the cache identifier.
To allow the use of these definitions by KVM for decoding cache ops,
break the definitions down into parts where it makes sense to do so, and
add masks for the Cache and Op field within the cache op.
James Hogan [Wed, 16 Dec 2015 23:49:34 +0000 (23:49 +0000)]
MIPS: Update trap codes
Add a few missing trap codes.
[ralf@linux-mips.org: Drop removal of exception codes. I don't care what
the incomplete architecture spec says; it can't change existing hardware
and VCEI is supported indeed.]
James Hogan [Wed, 16 Dec 2015 23:49:33 +0000 (23:49 +0000)]
MIPS: Move Cause.ExcCode trap codes to mipsregs.h
Move the Cause.ExcCode trap code definitions from kvm_host.h to
mipsregs.h, since they describe architectural bits rather than KVM
specific constants, and change the prefix from T_ to EXCCODE_.
James Hogan [Wed, 16 Dec 2015 23:49:31 +0000 (23:49 +0000)]
MIPS: KVM: Refactor added offsetof()s
When calculating the offsets into the commpage for dynamically
translated mtc0/mfc0 guest instructions, multiple offsetof()s are added
together to find the offset of the specific register in the mips_coproc,
within the commpage.
Simplify each of these cases to a single offsetof() to find the offset
of the specific register within the commpage.
James Hogan [Wed, 16 Dec 2015 23:49:28 +0000 (23:49 +0000)]
MIPS: Move definition of DC bit to mipsregs.h
The CAUSEB_DC and CAUSEF_DC definitions used by KVM are defined in
asm/kvm_host.h, but all the other Cause register field definitions are
found in asm/mipsregs.h.
Lets reunite the DC bit definitions with its friends in mipsregs.h.
James Hogan [Wed, 16 Dec 2015 23:49:27 +0000 (23:49 +0000)]
MIPS: KVM: Drop some unused definitions from kvm_host.h
Some definitions in the MIPS asm/kvm_host.h are completely unused, so
lets drop them.
MS_TO_NS is no longer used since commit e30492bbe95a ("MIPS: KVM:
Rewrite count/compare timer emulation"). The others don't appear ever to
have been used.
Joshua Henderson [Thu, 14 Jan 2016 01:15:39 +0000 (18:15 -0700)]
MIPS: Add support for PIC32MZDA platform
This adds support for the Microchip PIC32 MIPS microcontroller with the
specific variant PIC32MZDA. PIC32MZDA is based on the MIPS m14KEc core
and boots using device tree.
This includes an early pin setup and early clock setup needed prior to
device tree being initialized. In additon, an interface is provided to
synchronize access to registers shared across several peripherals.
Cristian Birsan [Thu, 14 Jan 2016 01:15:35 +0000 (18:15 -0700)]
IRQCHIP: irq-pic32-evic: Add support for PIC32 interrupt controller
This adds support for the interrupt controller present on PIC32 class
devices. It handles all internal and external interrupts. This controller
exists outside of the CPU core and is the arbitrator of all interrupts
(including interrupts from the CPU itself) before they are presented to
the CPU.
The following features are supported:
- DT properties for EVIC and for devices/peripherals that use interrupt lines
- Persistent and non-persistent interrupt handling
- irqdomain and generic chip support
- Configuration of external interrupt edge polarity
Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Joshua Henderson <joshua.henderson@microchip.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12092/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Tue, 22 Dec 2015 13:56:39 +0000 (13:56 +0000)]
MIPS: ptrace: Drop cp0_tcstatus from regoffset_table[]
The cp0_tcstatus member of struct pt_regs was removed along with the
rest of SMTC in v3.16, commit b633648c5ad3 ("MIPS: MT: Remove SMTC
support"), however recent uprobes support in v4.3 added back a reference
to it in the regoffset_table[] in ptrace.c. Remove it.
Linus Walleij [Tue, 22 Dec 2015 14:41:44 +0000 (15:41 +0100)]
MIPS: TXx9: iocled: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.
Linus Walleij [Tue, 22 Dec 2015 14:41:19 +0000 (15:41 +0100)]
MIPS: RB532: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.
Linus Walleij [Tue, 22 Dec 2015 14:41:01 +0000 (15:41 +0100)]
MIPS: TXx9: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.
Linus Walleij [Tue, 22 Dec 2015 14:40:27 +0000 (15:40 +0100)]
MIPS: ar7: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.
Linus Walleij [Tue, 22 Dec 2015 14:40:02 +0000 (15:40 +0100)]
MIPS: Alchemy: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.
Matt Redfearn [Fri, 18 Dec 2015 12:47:00 +0000 (12:47 +0000)]
MIPS: smp-cps: Ensure secondary cores start with EVA disabled
The kernel currently assumes that a core will start up in legacy mode
using the exception base provided through the CM GCR registers. If a
core has been configured in hardware to start in EVA mode, these
assumptions will fail.
This patch ensures that secondary cores are initialized to meet these
assumptions.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Reviewed-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11907/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix the description of the microMIPS NOP16 encoding or MM_NOP16, which
is not equivalent to the MIPS16 NOP instruction. This is 0x0c00 and
represents the microMIPS `MOVE16 $0, $0' operation, whereas MIPS16 NOP
is encoded as 0x6500, representing `MOVE $0, $16'.
Also fix a typo in `mm_fp0_format' description.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12177/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: math-emu: dsemul: Correct description of the emulation frame
Remove irrelevant content from the description of the emulation frame in
`mips_dsemul', referring to bare-metal configurations. Update the text,
reflecting the change made with commit ba3049ed4086 ("MIPS: Switch FPU
emulator trap to BREAK instruction."), where we switched from using an
address error exception on an unaligned access to the use of a BREAK 514
instruction causing a breakpoint exception instead.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12176/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: math-emu: Correct the emulation of microMIPS ADDIUPC instruction
Emulate the microMIPS ADDIUPC instruction directly in `mips_dsemul'. If
executed in the emulation frame, this instruction produces an incorrect
result, because the value of the PC there is not the same as where the
instruction originated.
Reshape code so as to handle all microMIPS cases together.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12175/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: math-emu: Make microMIPS branch delay slot emulation work
Complement commit 102cedc32a6e ("MIPS: microMIPS: Floating point
support.") which introduced microMIPS FPU emulation, but did not adjust
the encoding of the BREAK instruction used to terminate the branch delay
slot emulation frame. Consequently the execution of any such frame is
indeterminate and, depending on CPU configuration, will result in random
code execution or an offending program being terminated with SIGILL.
This is because the regular MIPS BREAK instruction is encoded with the 0
major and the 0xd minor opcode, however in the microMIPS instruction set
this major/minor opcode pair denotes an encoding reserved for the DSP
ASE. Instead the microMIPS BREAK instruction is encoded with the 0
major and the 0x7 minor opcode.
Use the correct BREAK encoding for microMIPS FPU emulation then.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12174/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: math-emu: dsemul: Fix ill formatting of microMIPS part
Correct formatting breakage introduced with commit 102cedc32a6e ("MIPS:
microMIPS: Floating point support."), so that further changes to this
code can be consistent.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12173/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix an issue introduced with commit 9ab4471c9f1b ("MIPS: math-emu:
Correct delay-slot exception propagation") where the emulation of a NOP
instruction signals the need to terminate the emulation loop. This in
turn, if the PC has not changed from the entry to the loop, will cause
the kernel to terminate the program with SIGILL.
Consider this program:
static double div(double d)
{
do
d /= 2.0;
while (d > .5);
return d;
}
int main(int argc, char **argv)
{
return div(argc);
}
Where the FPU emulator is used, depending on the number of command-line
arguments this code will either run to completion or terminate with
SIGILL.
If no arguments are specified, then BC1T will not be taken, NOP will not
be emulated and code will complete successfully.
If one argument is specified, then BC1T will be taken once and NOP will
be emulated. At this point the entry PC value will be 0x400498 and the
new PC value, set by `mips_dsemul' will be 0x4004a0, the target of BC1T.
The emulation loop will terminate, but SIGILL will not be issued,
because the PC has changed. The FPU emulator will be entered again and
on the second execution BC1T will not be taken, NOP will not be emulated
and code will complete successfully.
If two or more arguments are specified, then the first execution of BC1T
will proceed as above. Upon reentering the FPU emulator the emulation
loop will continue to BC1T, at which point the branch will be taken and
NOP emulated again. At this point however the entry PC value will be
0x4004a0, the same as the target of BC1T. This will make the emulator
conclude that execution has not advanced and therefore an unsupported
FPU instruction has been encountered, and SIGILL will be sent to the
process.
Fix the problem by extending the internal API of `mips_dsemul', making
it return -1 if no delay slot emulation frame has been made, the
instruction has been handled and execution of the emulation loop needs
to continue as if nothing happened. Remove code from `mips_dsemul' to
reproduce steps made by the emulation loop at the conclusion of each
iteration, as those will be reached normally now. Adjust call sites
accordingly. Document the API.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12172/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Huacai Chen [Thu, 21 Jan 2016 13:09:52 +0000 (21:09 +0800)]
MIPS: Fix some missing CONFIG_CPU_MIPSR6 #ifdefs
Commit be0c37c985eddc4 (MIPS: Rearrange PTE bits into fixed positions.)
defines fixed PTE bits for MIPS R2. Then, commit d7b631419b3d230a4d383
(MIPS: pgtable-bits: Fix XPA damage to R6 definitions.) adds the MIPS
R6 definitions in the same way as MIPS R2. But some R6 #ifdefs in the
later commit are missing, so in this patch I fix that.
Huacai Chen [Thu, 21 Jan 2016 13:09:51 +0000 (21:09 +0800)]
MIPS: sync-r4k: reduce skew while synchronization
While synchronization, count register will go backwards for the master.
If synchronise_count_master() runs before synchronise_count_slave(),
skew becomes even more. The skew is very harmful for CPU hotplug (CPU0
do synchronization with CPU1, then CPU0 do synchronization with CPU2
and CPU0's count goes backwards, so it will be out of sync with CPU1).
After the commit cf9bfe55f24973a8f40e2 (MIPS: Synchronize MIPS count one
CPU at a time), we needn't evaluate count_reference at the beginning of
synchronise_count_master() any more. Thus, we evaluate the initcount (It
seems like count_reference is redundant) in the 2nd loop. Since we write
the count register in the last loop, we don't need additional barriers
(the existing memory barriers are enough).
Moreover, I think we loop 3 times is enough to get a primed instruction
cache, this can also get less skew than looping 5 times.
Comments are also updated in this patch.
Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/12163/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>