Paul E. McKenney [Sat, 11 Jul 2015 23:24:45 +0000 (16:24 -0700)]
rcu: Add fastpath bypassing funnel locking
In the common case, there will be only one expedited grace period in
the system at a given time, in which case it is not helpful to use
funnel locking. This commit therefore adds a fastpath that bypasses
funnel locking when the root ->exp_funnel_mutex is not held.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The grace-period kthread sleeps waiting to do a force-quiescent-state
scan, and when awakened sets rsp->gp_state to RCU_GP_DONE_FQS.
However, this is confusing because the kthread has not done the
force-quiescent-state, but is instead just starting to do it. This commit
therefore renames RCU_GP_DONE_FQS to RCU_GP_DOING_FQS in order to make
things a bit easier on reviewers.
Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 30 Jun 2015 18:14:32 +0000 (11:14 -0700)]
rcu: Add stall warnings to synchronize_sched_expedited()
Although synchronize_sched_expedited() historically has no RCU CPU stall
warnings, the availability of the rcupdate.rcu_expedited boot parameter
invalidates the old assumption that synchronize_sched()'s stall warnings
would suffice. This commit therefore adds RCU CPU stall warnings to
synchronize_sched_expedited().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Tue, 30 Jun 2015 00:06:39 +0000 (17:06 -0700)]
rcu: Extend expedited funnel locking to rcu_data structure
The strictly rcu_node based funnel-locking scheme works well in many
cases, but systems with CONFIG_RCU_FANOUT_LEAF=64 won't necessarily get
all that much concurrency. This commit therefore extends the funnel
locking into the per-CPU rcu_data structure, providing concurrency equal
to the number of CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Sat, 27 Jun 2015 16:36:29 +0000 (09:36 -0700)]
rcu: Consolidate last open-coded expedited memory barrier
One of the requirements on RCU grace periods is that if there is a
causal chain of operations that starts after one grace period and
ends before another grace period, then the two grace periods must
be serialized. There has been (and might still be) code that relies
on this, for example, certain types of reference-counting code that
does a call_rcu() within an RCU callback function.
This requirement is why there is an smp_mb() at the end of both
synchronize_sched_expedited() and synchronize_rcu_expedited().
However, this is the only smp_mb() in these functions, so it would
be nicer to consolidate it into rcu_exp_gp_seq_end(). This commit
does just that.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Fri, 26 Jun 2015 02:03:16 +0000 (19:03 -0700)]
rcu: Use funnel locking for synchronize_rcu_expedited()'s polling loop
This commit gets rid of synchronize_rcu_expedited()'s mutex_trylock()
polling loop in favor of the funnel-locking scheme that was abstracted
from synchronize_sched_expedited().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 25 Jun 2015 22:52:50 +0000 (15:52 -0700)]
rcu: Make synchronize_rcu_expedited() use sequence-counter scheme
Although synchronize_rcu_expedited() uses a sequence-counter scheme, it
is based on a single increment per grace period, which means that tasks
piggybacking off of concurrent grace periods may be forced to wait longer
than necessary. This commit therefore applies the new sequence-count
functions developed for synchronize_sched_expedited() to speed things
up a bit and to consolidate the sequence-counter implementation.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 25 Jun 2015 22:00:58 +0000 (15:00 -0700)]
rcu: Abstract sequence counting from synchronize_sched_expedited()
This commit creates rcu_exp_gp_seq_start() and rcu_exp_gp_seq_end() to
bracket an expedited grace period, rcu_exp_gp_seq_snap() to snapshot the
sequence counter, and rcu_exp_gp_seq_done() to check to see if a full
expedited grace period has elapsed since the snapshot. These will be
applied to synchronize_rcu_expedited(). These are defined in terms of
underlying rcu_seq_start(), rcu_seq_end(), rcu_seq_snap(), rcu_seq_done(),
which will be applied to _rcu_barrier().
One reason that this commit doesn't use the seqcount primitives themselves
is that the smp_wmb() in those primitive is insufficient due to the fact
that expedited grace periods do reads as well as writes. In addition,
the read-side seqcount primitives detect a potentially partial change,
where the expedited primitives instead need a guaranteed full change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Peter Zijlstra [Thu, 25 Jun 2015 18:27:10 +0000 (11:27 -0700)]
rcu: Make expedited GP CPU stoppage asynchronous
Sequentially stopping the CPUs slows down expedited grace periods by
at least a factor of two, based on rcutorture's grace-period-per-second
rate. This is a conservative measure because rcutorture uses unusually
long RCU read-side critical sections and because rcutorture periodically
quiesces the system in order to test RCU's ability to ramp down to and
up from the idle state. This commit therefore replaces the stop_one_cpu()
with stop_one_cpu_nowait(), using an atomic-counter scheme to determine
when all CPUs have passed through the stopped state.
Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Wed, 24 Jun 2015 21:20:08 +0000 (14:20 -0700)]
rcu: Get rid of synchronize_sched_expedited()'s polling loop
This commit gets rid of synchronize_sched_expedited()'s mutex_trylock()
polling loop in favor of a funnel-locking scheme based on the rcu_node
tree. The work-done check is done at each level of the tree, allowing
high-contention situations to be resolved quickly with reasonable levels
of mutex contention.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that synchronize_sched_expedited() have a mutex, it can use simpler
work-already-done detection scheme. This commit simplifies this scheme
by using something similar to the sequence-locking counter scheme.
A counter is incremented before and after each grace period, so that
the counter is odd in the midst of the grace period and even otherwise.
So if the counter has advanced to the second even number that is
greater than or equal to the snapshot, the required grace period has
already happened.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Peter Zijlstra [Wed, 24 Jun 2015 02:03:45 +0000 (19:03 -0700)]
rcu: Switch synchronize_sched_expedited() to stop_one_cpu()
The synchronize_sched_expedited() currently invokes try_stop_cpus(),
which schedules the stopper kthreads on each online non-idle CPU,
and waits until all those kthreads are running before letting any
of them stop. This is disastrous for real-time workloads, which
get hit with a preemption that is as long as the longest scheduling
latency on any CPU, including any non-realtime housekeeping CPUs.
This commit therefore switches to using stop_one_cpu() on each CPU
in turn. This avoids inflicting the worst-case scheduling latency
on the worst-case CPU onto all other CPUs, and also simplifies the
code a little bit.
Follow-up commits will simplify the counter-snapshotting algorithm
and convert a number of the counters that are now protected by the
new ->expedited_mutex to non-atomic.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
[ paulmck: Kept stop_one_cpu(), dropped disabling of "guardrails". ] Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 11 Jun 2015 22:22:43 +0000 (15:22 -0700)]
rcu: Remove CONFIG_RCU_CPU_STALL_INFO
The CONFIG_RCU_CPU_STALL_INFO has been default-y for a couple of
releases with no complaints, so it is time to eliminate this Kconfig
option entirely, so that the long-form RCU CPU stall warnings cannot
be disabled. This commit does just that.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Paul E. McKenney [Thu, 11 Jun 2015 21:50:22 +0000 (14:50 -0700)]
rcu: Stop disabling CPU hotplug in synchronize_rcu_expedited()
The fact that tasks could be migrated from leaf to root rcu_node
structures meant that synchronize_rcu_expedited() had to disable
CPU hotplug. However, tasks now stay put, so this commit removes the
CPU-hotplug disabling from synchronize_rcu_expedited().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently if the rcu_fanout_leaf boot parameter is out of bounds (that
is, less than RCU_FANOUT_LEAF or greater than the number of bits in an
unsigned long), a warning is issued and execution continues with the
out-of-bounds value. This can result in all manner of failures, so this
patch resets rcu_fanout_leaf to RCU_FANOUT_LEAF when an out-of-bounds
condition is detected.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Because gcc does not realize a loop would not be entered ever
(i.e. in case of rcu_num_lvls == 1):
for (i = 1; i < rcu_num_lvls; i++)
rsp->level[i] = rsp->level[i - 1] + levelcnt[i - 1];
some compiler (pre- 5.x?) versions give a bogus warning:
kernel/rcu/tree.c: In function ‘rcu_init_one.isra.55’:
kernel/rcu/tree.c:4108:13: warning: array subscript is above array bounds [-Warray-bounds]
rsp->level[i] = rsp->level[i - 1] + rsp->levelcnt[i - 1];
^
Fix that warning by adding an extra item to rcu_state::level[]
array. Once the bogus warning is fixed in gcc and kernel drops
support of older versions, the dummy item may be removed from
the array.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Suggested-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Simplify arithmetic to calculate number of RCU nodes
This update makes arithmetic to calculate number of RCU nodes
more straight and easy to read.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Limit count of static data to the number of RCU levels
Although a number of RCU levels may be less than the current
maximum of four, some static data associated with each level
are allocated for all four levels. As result, the extra data
never get accessed and just wast memory. This update limits
count of allocated items to the number of used RCU levels.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Remove unnecessary fields from rcu_state structure
Members rcu_state::levelcnt[] and rcu_state::levelspread[]
are only used at init. There is no reason to keep them
afterwards.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Limit rcu_capacity[] size to RCU_NUM_LVLS items
Number of items in rcu_capacity[] array is defined by macro
MAX_RCU_LVLS. However, that array is never accessed beyond
RCU_NUM_LVLS index. Therefore, we can limit the array to
RCU_NUM_LVLS items and eliminate MAX_RCU_LVLS. As result,
in most cases the memory is conserved.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Limit rcu_state::levelcnt[] to RCU_NUM_LVLS items
Variable rcu_num_lvls is limited by RCU_NUM_LVLS macro.
In turn, rcu_state::levelcnt[] array is never accessed
beyond rcu_num_lvls. Thus, rcu_state::levelcnt[] is safe
to limit to RCU_NUM_LVLS items.
Since rcu_num_lvls could be changed during boot (as result
of rcutree.rcu_fanout_leaf kernel parameter update) one might
assume a new value could overflow the value of RCU_NUM_LVLS.
However, that is not the case, since leaf-level fanout is only
permitted to increase, resulting in rcu_num_lvls possibly to
decrease.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Current code suggests that introducing the extra level to
rcu_capacity[] array makes some of the arithmetic easier.
Well, in fact it appears rather confusing and unnecessary.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Cleanup rcu_init_geometry() code and arithmetics
This update simplifies rcu_init_geometry() code flow
and makes calculation of the total number of rcu_node
structures more easy to read.
The update relies on the fact num_rcu_lvl[] is never
accessed beyond rcu_num_lvls index by the rest of the
code. Therefore, there is no need initialize the whole
num_rcu_lvl[].
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Remove superfluous local variable in rcu_init_geometry()
Local variable 'n' mimics 'nr_cpu_ids' while the both are
used within one function. There is no reason for 'n' to
exist whatsoever.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcu: Panic if RCU tree can not accommodate all CPUs
Currently a condition when RCU tree is unable to accommodate
the configured number of CPUs is not permitted and causes
a fall back to compile-time values. However, the code has no
means to exceed the RCU tree capacity neither at compile-time
nor in run-time. Therefore, if the condition is met in run-
time then it indicates a serios problem elsewhere and should
be handled with a panic.
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Merge tag 'platform-drivers-x86-v4.2-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86
Pull late x86 platform driver updates from Darren Hart:
"The following came in a bit later and I wanted them to bake in next a
few more days before submitting, thus the second pull.
A new intel_pmc_ipc driver, a symmetrical allocation and free fix in
dell-laptop, a couple minor fixes, and some updated documentation in
the dell-laptop comments.
intel_pmc_ipc:
- Add Intel Apollo Lake PMC IPC driver
tc1100-wmi:
- Delete an unnecessary check before the function call "kfree"
dell-laptop:
- Fix allocating & freeing SMI buffer page
- Show info about WiGig and UWB in debugfs
- Update information about wireless control"
* tag 'platform-drivers-x86-v4.2-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
intel_pmc_ipc: Add Intel Apollo Lake PMC IPC driver
tc1100-wmi: Delete an unnecessary check before the function call "kfree"
dell-laptop: Fix allocating & freeing SMI buffer page
dell-laptop: Show info about WiGig and UWB in debugfs
dell-laptop: Update information about wireless control
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
Commit 835a6a2f8603 ("Bluetooth: Stop sabotaging list poisoning")
thought that the code was sabotaging the list poisoning when NULL'ing
out the list pointers and removed it.
But what was going on was that the bluetooth code was using NULL
pointers for the list as a way to mark it empty, and that commit just
broke it (and replaced the test with NULL with a "list_empty()" test on
a uninitialized list instead, breaking things even further).
So fix it all up to use the regular and real list_empty() handling
(which does not use NULL, but a pointer to itself), also making sure to
initialize the list properly (the previous NULL case was initialized
implicitly by the session being allocated with kzalloc())
This is a combination of patches by Marcel Holtmann and Tedd Ho-Jeong
An.
[ I would normally expect to get this through the bt tree, but I'm going
to release -rc1, so I'm just committing this directly - Linus ]
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
"It's been a busy development cycle for target-core in a number of
different areas.
The fabric API usage for se_node_acl allocation is now within
target-core code, dropping the external API callers for all fabric
drivers tree-wide.
There is a new conversion to RCU hlists for se_node_acl and
se_portal_group LUN mappings, that turns fast-past LUN lookup into a
completely lockless code-path. It also removes the original
hard-coded limitation of 256 LUNs per fabric endpoint.
The configfs attributes for backends can now be shared between core
and driver code, allowing existing drivers to use common code while
still allowing flexibility for new backend provided attributes.
The highlights include:
- Merge sbc_verify_dif_* into common code (sagi)
- Remove iscsi-target support for obsolete IFMarker/OFMarker
(Christophe Vu-Brugier)
- Add bidi support in target/user backend (ilias + vangelis + agover)
- Move se_node_acl allocation into target-core code (hch)
- Add crc_t10dif_update common helper (akinobu + mkp)
- Handle target-core odd SGL mapping for data transfer memory
(akinobu)
- Move transport ID handling into target-core (hch)
- Move task tag into struct se_cmd + support 64-bit tags (bart)
- Convert se_node_acl->device_list[] to RCU hlist (nab + hch +
paulmck)
- Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch +
paulmck)
- Simplify target backend driver registration (hch)
- Consolidate + simplify target backend attribute implementations
(hch + nab)
- Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch)
- Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab)
- Drop unnecessary core_tpg_register TFO parameter (nab)
- Use 64-bit LUNs tree-wide (hannes)
- Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits)
target: Bump core version to v5.0
target: remove target_core_configfs.h
target: remove unused TARGET_CORE_CONFIG_ROOT define
target: consolidate version defines
target: implement WRITE_SAME with UNMAP bit using ->execute_unmap
target: simplify UNMAP handling
target: replace se_cmd->execute_rw with a protocol_data field
target/user: Fix inconsistent kmap_atomic/kunmap_atomic
target: Send UA when changing LUN inventory
target: Send UA upon LUN RESET tmr completion
target: Send UA on ALUA target port group change
target: Convert se_lun->lun_deve_lock to normal spinlock
target: use 'se_dev_entry' when allocating UAs
target: Remove 'ua_nacl' pointer from se_ua structure
target_core_alua: Correct UA handling when switching states
xen-scsiback: Fix compile warning for 64-bit LUN
target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
target: use 64-bit LUNs
target: Drop duplicate + unused se_dev_check_wce
target: Drop unnecessary core_tpg_register TFO parameter
...
Merge tag 'ntb-4.2' of git://github.com/jonmason/ntb
Pull NTB updates from Jon Mason:
"This includes a pretty significant reworking of the NTB core code, but
has already produced some significant performance improvements.
An abstraction layer was added to allow the hardware and clients to be
easily added. This required rewriting the NTB transport layer for
this abstraction layer. This modification will allow future "high
performance" NTB clients.
In addition to this change, a number of performance modifications were
added. These changes include NUMA enablement, using CPU memcpy
instead of asyncdma, and modification of NTB layer MTU size"
* tag 'ntb-4.2' of git://github.com/jonmason/ntb: (22 commits)
NTB: Add split BAR output for debugfs stats
NTB: Change WARN_ON_ONCE to pr_warn_once on unsafe
NTB: Print driver name and version in module init
NTB: Increase transport MTU to 64k from 16k
NTB: Rename Intel code names to platform names
NTB: Default to CPU memcpy for performance
NTB: Improve performance with write combining
NTB: Use NUMA memory in Intel driver
NTB: Use NUMA memory and DMA chan in transport
NTB: Rate limit ntb_qp_link_work
NTB: Add tool test client
NTB: Add ping pong test client
NTB: Add parameters for Intel SNB B2B addresses
NTB: Reset transport QP link stats on down
NTB: Do not advance transport RX on link down
NTB: Differentiate transport link down messages
NTB: Check the device ID to set errata flags
NTB: Enable link for Intel root port mode in probe
NTB: Read peer info from local SPAD in transport
NTB: Split ntb_hw_intel and ntb_transport drivers
...
Al Viro [Sat, 4 Jul 2015 20:11:05 +0000 (16:11 -0400)]
p9_client_write(): avoid double p9_free_req()
Braino in "9p: switch p9_client_write() to passing it struct iov_iter *";
if response is impossible to parse and we discard the request, get the
out of the loop right there.
Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Sat, 4 Jul 2015 20:04:19 +0000 (16:04 -0400)]
9p: forgetting to cancel request on interrupted zero-copy RPC
If we'd already sent a request and decide to abort it, we *must*
issue TFLUSH properly and not just blindly reuse the tag, or
we'll get seriously screwed when response eventually arrives
and we confuse it for response to later request that had reused
the same tag.
Cc: stable@vger.kernel.org # v3.2 and later Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Matthew Wilcox [Fri, 3 Jul 2015 14:40:43 +0000 (10:40 -0400)]
dax: bdev_direct_access() may sleep
The brd driver is the only in-tree driver that may sleep currently.
After some discussion on linux-fsdevel, we decided that any driver
may choose to sleep in its ->direct_access method. To ensure that all
callers of bdev_direct_access() are prepared for this, add a call
to might_sleep().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Matthew Wilcox [Fri, 3 Jul 2015 14:40:42 +0000 (10:40 -0400)]
block: Add support for DAX reads/writes to block devices
If a block device supports the ->direct_access methods, bypass the normal
DIO path and use DAX to go straight to memcpy() instead of allocating
a DIO and a BIO.
Includes support for the DIO_SKIP_DIO_COUNT flag in DAX, as is done in
do_blockdev_direct_IO().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"Except for the preempt notifiers fix, these are all small bugfixes
that could have been waited for -rc2. Sending them now since I was
taking care of Peter's patch anyway"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: add hyper-v crash msrs values
KVM: x86: remove data variable from kvm_get_msr_common
KVM: s390: virtio-ccw: don't overwrite config space values
KVM: x86: keep track of LVT0 changes under APICv
KVM: x86: properly restore LVT0
KVM: x86: make vapics_in_nmi_mode atomic
sched, preempt_notifier: separate notifier registration from static_key inc/dec
Dave Jiang [Tue, 19 May 2015 20:52:04 +0000 (16:52 -0400)]
NTB: Default to CPU memcpy for performance
Disable DMA usage by default, since the CPU provides much better
performance with write combining. Provide a module parameter to enable
DMA usage when offloading the memcpy is preferred.
Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Dave Jiang [Tue, 19 May 2015 20:45:46 +0000 (16:45 -0400)]
NTB: Improve performance with write combining
Changing the memory window BAR mappings to write combining significantly
boosts the performance. We will also use memcpy that uses non-temporal
store, which showed performance improvement when doing non-cached
memcpys.
Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Allen Hubbe [Mon, 11 May 2015 14:08:26 +0000 (10:08 -0400)]
NTB: Rate limit ntb_qp_link_work
When the ntb transport is connecting and waiting for the peer, the debug
console receives lots of debug level messages about the remote qp link
status being down. Rate limit those messages.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Allen Hubbe [Thu, 21 May 2015 06:51:39 +0000 (02:51 -0400)]
NTB: Add tool test client
This is a simple debugging driver that enables the doorbell and
scratch pad registers to be read and written from the debugfs. This
tool enables more complicated debugging to be scripted from user space.
This driver may be used to test that your ntb hardware and drivers are
functioning at a basic level.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Allen Hubbe [Wed, 15 Apr 2015 15:12:41 +0000 (11:12 -0400)]
NTB: Add ping pong test client
This is a simple ping pong driver that exercises the scratch pads and
doorbells of the ntb hardware. This driver may be used to test that
your ntb hardware and drivers are functioning at a basic level.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Allen Hubbe [Tue, 12 May 2015 12:09:15 +0000 (08:09 -0400)]
NTB: Reset transport QP link stats on down
Reset the link stats when the link goes down. In particular, the TX and
RX index and count must be reset, or else the TX side will be sending
packets to the RX side where the RX side is not expecting them. Reset
all the stats, to be consistent.
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Dave Jiang [Tue, 19 May 2015 20:59:34 +0000 (16:59 -0400)]
NTB: Enable link for Intel root port mode in probe
Link training should be enabled in the driver probe for root port mode.
We should not have to wait for transport to be loaded for this to
happen. Otherwise the ntb device will not show up on the transparent
bridge side of the link.
Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Dave Jiang [Tue, 2 Jun 2015 07:45:07 +0000 (03:45 -0400)]
NTB: Read peer info from local SPAD in transport
The transport was writing and then reading the peer scratch pad,
essentially reading what it just wrote instead of exchanging any
information with the peer. The transport expects the peer values to be
the same as the local values, so this issue was not obvious.
Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq update from Thomas Gleixner:
"The last update for 4.2 is just moving a macro from a local header to
the global one, so it can be used in architecture code as well.
Cleanup of the now empty local header is 4.3 material"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip: Move IRQCHIP_DECLARE macro to include/linux/irqchip.h
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Two FPU rewrite related fixes. This addresses all known x86
regressions at this stage. Also some other misc fixes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu: Fix boot crash in the early FPU code
x86/asm/entry/64: Update path names
x86/fpu: Fix FPU related boot regression when CPUID masking BIOS feature is enabled
x86/boot/setup: Clean up the e820_reserve_setup_data() code
x86/kaslr: Fix typo in the KASLR_FLAG documentation
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Debug info and other statistics fixes and related enhancements"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/numa: Fix numa balancing stats in /proc/pid/sched
sched/numa: Show numa_group ID in /proc/sched_debug task listings
sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h
sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y
sched/stat: Simplify the sched_info accounting dependency
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
"This tree includes an x86 PMU scheduling fix, but most changes are
late breaking tooling fixes and updates:
User visible fixes:
- Create config.detected into OUTPUT directory, fixing parallel
builds sharing the same source directory (Aaro Kiskinen)
- Allow to specify custom linker command, fixing some MIPS64 builds.
(Aaro Kiskinen)
- Fix to show proper convergence stats in 'perf bench numa' (Srikar
Dronamraju)
User visible changes:
- Validate syscall list passed via -e argument to 'perf trace'.
(Arnaldo Carvalho de Melo)
- Introduce 'perf stat --per-thread' (Jiri Olsa)
- Check access permission for --kallsyms and --vmlinux (Li Zhang)
- Move toggling event logic from 'perf top' and into hists browser,
allowing freeze/unfreeze with event lists with more than one entry
(Namhyung Kim)
- Add missing newlines when dumping PERF_RECORD_FINISHED_ROUND and
showing the Aggregated stats in 'perf report -D' (Adrian Hunter)
Infrastructure fixes:
- Add missing break for PERF_RECORD_ITRACE_START, which caused those
events samples to be parsed as well as PERF_RECORD_LOST_SAMPLES.
ITRACE_START only appears when Intel PT or BTS are present, so..
(Jiri Olsa)
- Call the perf_session destructor when bailing out in the inject,
kmem, report, kvm and mem tools (Taeung Song)
Infrastructure changes:
- Move stuff out of 'perf stat' and into the lib for further use
(Jiri Olsa)
- Reference count the cpu_map and thread_map classes (Jiri Olsa)
- Set evsel->{cpus,threads} from the evlist, if not set, allowing the
generalization of some 'perf stat' functions that previously were
accessing private static evlist variable (Jiri Olsa)
- Delete an unnecessary check before the calling free_event_desc()
(Markus Elfring)
- Allow auxtrace data alignment (Adrian Hunter)
- Allow events with dot (Andi Kleen)
- Fix failure to 'perf probe' events on arm (He Kuang)
- Add testing for Makefile.perf (Jiri Olsa)
- Add test for make install with prefix (Jiri Olsa)
- Fix single target build dependency check (Jiri Olsa)
- Access thread_map entries via accessors, prep patch to hold more
info per entry, for ongoing 'perf stat --per-thread' work (Jiri
Olsa)
- Use __weak definition from compiler.h (Sukadev Bhattiprolu)
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
perf tools: Allow to specify custom linker command
perf tools: Create config.detected into OUTPUT directory
perf mem: Fill in the missing session freeing after an error occurs
perf kvm: Fill in the missing session freeing after an error occurs
perf report: Fill in the missing session freeing after an error occurs
perf kmem: Fill in the missing session freeing after an error occurs
perf inject: Fill in the missing session freeing after an error occurs
perf tools: Add missing break for PERF_RECORD_ITRACE_START
perf/x86: Fix 'active_events' imbalance
perf symbols: Check access permission when reading symbol files
perf stat: Introduce --per-thread option
perf stat: Introduce print_counters function
perf stat: Using init_stats instead of memset
perf stat: Rename print_interval to process_interval
perf stat: Remove perf_evsel__read_cb function
perf stat: Move perf_stat initialization counter process code
perf stat: Move zero_per_pkg into counter process code
perf stat: Separate counters reading and processing
perf stat: Introduce read_counters function
perf stat: Introduce perf_evsel__read function
...
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull second round of input updates from Dmitry Torokhov:
"A new driver for Weida wdt87xx touch controllers, and a bunch of
fixups for other drivers"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: wdt87xx_i2c - add a scaling factor for TOUCH_MAJOR event
Input: wdt87xx_i2c - remove stray newline in diagnostic message
Input: arc_ps2 - add HAS_IOMEM dependency
Input: wdt87xx_i2c - fix format warning
Input: improve parsing OF parameters for touchscreens
Input: edt-ft5x06 - mark as direct input device
Input: use for_each_set_bit() where appropriate
Input: add a driver for wdt87xx touchscreen controller
Input: axp20x-pek - fix reporting button state as inverted
Input: xpad - re-send LED command on present event
Input: xpad - set the LEDs properly on XBox Wireless controllers
Input: imx_keypad - check for clk_prepare_enable() error
91a8c2a5b43f ("x86/fpu: Clean up and fix MXCSR handling")
The reason is that the on-stack FPU registers state variable,
used by the FXSAVE instruction, did not have the required
minimum alignment of 16 bytes, causing the general protection
fault.
This is most likely a GCC bug in older GCC versions, but the
offending commit also added a bogus extra 32-byte alignment
(which GCC ignored too).
So fix this bug by making the variable static again, but also
mark it __initdata this time, because fpu__init_system_mxcsr()
is now an __init function.
Reported-and-bisected-by: Jan Kara <jack@suse.cz> Reported-bisected-and-tested-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Kara <jack@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150704075819.GA9201@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
sched/numa: Fix numa balancing stats in /proc/pid/sched
Commit 44dba3d5d6a1 ("sched: Refactor task_struct to use
numa_faults instead of numa_* pointers") modified the way
tsk->numa_faults stats are accounted.
However that commit never touched show_numa_stats() that is displayed
in /proc/pid/sched and thus the numbers displayed in /proc/pid/sched
don't match the actual numbers.
Fix it by making sure that /proc/pid/sched reflects the task
fault numbers. Also add group fault stats too.
Also couple of more modifications are added here:
1. Format changes:
- Previously we would list two entries per node, one for private
and one for shared. Also the home node info was listed in each entry.
- Now preferred node, total_faults and current node are
displayed separately.
- Now there is one entry per node, that lists private,shared task and
group faults.
2. Unit changes:
- p->numa_pages_migrated was getting reset after every read of
/proc/pid/sched. It's more useful to have absolute numbers since
differential migrations between two accesses can be more easily
calculated.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Iulia Manda <iulia.manda21@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1435252903-1081-4-git-send-email-srikar@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
sched/debug: Move print_cfs_rq() declaration to kernel/sched/sched.h
Currently print_cfs_rq() is declared in include/linux/sched.h.
However it's not used outside kernel/sched. Hence move the
declaration to kernel/sched/sched.h
Also some functions are only available for CONFIG_SCHED_DEBUG=y.
Hence move the declarations to within the #ifdef.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Iulia Manda <iulia.manda21@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1435252903-1081-2-git-send-email-srikar@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Naveen N. Rao [Tue, 30 Jun 2015 09:06:03 +0000 (14:36 +0530)]
sched/stat: Expose /proc/pid/schedstat if CONFIG_SCHED_INFO=y
Expand /proc/pid/schedstat output:
- enable it on CONFIG_TASK_DELAY_ACCT=y && !CONFIG_SCHEDSTATS kernels.
- dump all zeroes on kernels that are booted with the 'nodelayacct'
option, which boot option disables delay accounting on
CONFIG_TASK_DELAY_ACCT=y kernels.
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio/vhost cross endian support from Michael Tsirkin:
"I have just queued some more bugfix patches today but none fix
regressions and none are related to these ones, so it looks like a
good time for a merge for -rc1.
The motivation for this is support for legacy BE guests on the new LE
hosts. There are two redeeming properties that made me merge this:
- It's a trivial amount of code: since we wrap host/guest accesses
anyway, almost all of it is well hidden from drivers.
- Sane platforms would never set flags like VHOST_CROSS_ENDIAN_LEGACY,
and when it's clear, there's zero overhead (as some point it was
tested by compiling with and without the patches, got the same
stripped binary).
Maybe we could create a Kconfig symbol to enforce the second point:
prevent people from enabling it eg on x86. I will look into this"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio-pci: alloc only resources actually used.
macvtap/tun: cross-endian support for little-endian hosts
vhost: cross-endian support for legacy devices
virtio: add explicit big-endian support to memory accessors
vhost: introduce vhost_is_little_endian() helper
vringh: introduce vringh_is_little_endian() helper
macvtap: introduce macvtap_is_little_endian() helper
tun: add tun_is_little_endian() helper
virtio: introduce virtio_is_little_endian() helper
The length of each EDID block is EDID_LENGTH, and number of blocks is
(1 + edid->extensions) - we need to multiply not add them.
This causes wrong EDID to be passed on, and is a regression introduced
by d2ed34362a52 (drm: Introduce helper for replacing blob properties)
Signed-off-by: Shixin Zeng <zeng.shixin@gmail.com> Cc: Daniel Stone <daniels@collabora.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Daniel Stone <daniels@collabora.com>
[danvet: Add Cc: and fix commit summary.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
"Long ago and far away when user namespaces where young it was realized
that allowing fresh mounts of proc and sysfs with only user namespace
permissions could violate the basic rule that only root gets to decide
if proc or sysfs should be mounted at all.
Some hacks were put in place to reduce the worst of the damage could
be done, and the common sense rule was adopted that fresh mounts of
proc and sysfs should allow no more than bind mounts of proc and
sysfs. Unfortunately that rule has not been fully enforced.
There are two kinds of gaps in that enforcement. Only filesystems
mounted on empty directories of proc and sysfs should be ignored but
the test for empty directories was insufficient. So in my tree
directories on proc, sysctl and sysfs that will always be empty are
created specially. Every other technique is imperfect as an ordinary
directory can have entries added even after a readdir returns and
shows that the directory is empty. Special creation of directories
for mount points makes the code in the kernel a smidge clearer about
it's purpose. I asked container developers from the various container
projects to help test this and no holes were found in the set of mount
points on proc and sysfs that are created specially.
This set of changes also starts enforcing the mount flags of fresh
mounts of proc and sysfs are consistent with the existing mount of
proc and sysfs. I expected this to be the boring part of the work but
unfortunately unprivileged userspace winds up mounting fresh copies of
proc and sysfs with noexec and nosuid clear when root set those flags
on the previous mount of proc and sysfs. So for now only the atime,
read-only and nodev attributes which userspace happens to keep
consistent are enforced. Dealing with the noexec and nosuid
attributes remains for another time.
This set of changes also addresses an issue with how open file
descriptors from /proc/<pid>/ns/* are displayed. Recently readlink of
/proc/<pid>/fd has been triggering a WARN_ON that has not been
meaningful since it was added (as all of the code in the kernel was
converted) and is not now actively wrong.
There is also a short list of issues that have not been fixed yet that
I will mention briefly.
It is possible to rename a directory from below to above a bind mount.
At which point any directory pointers below the renamed directory can
be walked up to the root directory of the filesystem. With user
namespaces enabled a bind mount of the bind mount can be created
allowing the user to pick a directory whose children they can rename
to outside of the bind mount. This is challenging to fix and doubly
so because all obvious solutions must touch code that is in the
performance part of pathname resolution.
As mentioned above there is also a question of how to ensure that
developers by accident or with purpose do not introduce exectuable
files on sysfs and proc and in doing so introduce security regressions
in the current userspace that will not be immediately obvious and as
such are likely to require breaking userspace in painful ways once
they are recognized"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
vfs: Remove incorrect debugging WARN in prepend_path
mnt: Update fs_fully_visible to test for permanently empty directories
sysfs: Create mountpoints with sysfs_create_mount_point
sysfs: Add support for permanently empty directories to serve as mount points.
kernfs: Add support for always empty directories.
proc: Allow creating permanently empty directories that serve as mount points
sysctl: Allow creating permanently empty directories that serve as mountpoints.
fs: Add helper functions for permanently empty directories.
vfs: Ignore unlocked mounts in fs_fully_visible
mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
mnt: Refactor the logic for mounting sysfs and proc in a user namespace
Merge tag 'remoteproc-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/remoteproc
Pull remoteproc updates from Ohad Ben-Cohen:
- remoteproc fixes/cleanups from Suman Anna
- new remoteproc TI Wakeup M3 driver from Dave Gerlach
- remoteproc core support for TI's Wakeup M3 driver from both Dave and Suman
- tiny remoteproc build fix from myself
* tag 'remoteproc-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/remoteproc:
remoteproc: fix !CONFIG_OF build breakage
remoteproc/wkup_m3: add a remoteproc driver for TI Wakeup M3
Documentation: dt: add bindings for TI Wakeup M3 processor
remoteproc: add a rproc ops for performing address translation
remoteproc: introduce rproc_get_by_phandle API
remoteproc: fix various checkpatch warnings
remoteproc/davinci: fix quoted split string checkpatch warning
remoteproc/ste: add blank lines after declarations
Merge tag 'hwspinlock-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock
Pull hwspinlock updates from Ohad Ben-Cohen:
- hwspinlock core DT support from Suman Anna
- OMAP hwspinlock DT support from Suman Anna
- QCOM hwspinlock DT support from Bjorn Andersson
- a new CSR atlas7 hwspinlock driver from Wei Chen
- CSR atlas7 hwspinlock DT binding document from Wei Chen
- a tiny QCOM hwspinlock driver fix from Bjorn Andersson
* tag 'hwspinlock-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock:
hwspinlock: qcom: Correct msb in regmap_field
DT: hwspinlock: add the CSR atlas7 hwspinlock bindings document
hwspinlock: add a CSR atlas7 driver
hwspinlock: qcom: Add support for Qualcomm HW Mutex block
DT: hwspinlock: Add binding documentation for Qualcomm hwmutex
hwspinlock/omap: add support for dt nodes
Documentation: dt: add the omap hwspinlock bindings document
hwspinlock/core: add device tree support
Documentation: dt: add common bindings for hwspinlock
- suspicious RCU usage warning
- BPF (out of bounds array read and endianness conversion)
- perf (of_node usage after of_node_put, cpu_pmu->plat_device
assignment)
- huge pmd/pud check for value 0
- rate-limiting should only take unhandled signals into account
Clean-up:
- incorrect use of pgprot_t type
- unused header include
- __init annotation to arm_cpuidle_init
- pr_debug instead of pr_error for disabled GICC entries in
ACPI/MADT"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Fix show_unhandled_signal_ratelimited usage
ARM64 / SMP: Switch pr_err() to pr_debug() for disabled GICC entry
arm64: cpuidle: add __init section marker to arm_cpuidle_init
arm64: Don't report clear pmds and puds as huge
arm64: perf: fix unassigned cpu_pmu->plat_device when probing PMU PPIs
arm64: perf: Don't use of_node after putting it
arm64: fix incorrect use of pgprot_t variable
arm64/hw_breakpoint.c: remove unnecessary header
arm64: bpf: fix endianness conversion bugs
arm64: bpf: fix out-of-bounds read in bpf2a64_offset()
ARM64: smp: Fix suspicious RCU usage with ipi tracepoints
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
Pull more hwmon updates from Jean Delvare.
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (w83627ehf) Use swap() in w82627ehf_swap_tempreg()
hwmon: Document which I2C addresses can be probed
hwmon: (w83792d) Additional PWM outputs support
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Mainly sending this off now for the writeback fixes, since they fix a
real regression introduced with the cgroup writeback changes. The
NVMe fix could wait for next pull for this series, but it's simple
enough that we might as well include it.
This contains:
- two cgroup writeback fixes from Tejun, fixing a user reported issue
with luks crypt devices hanging when being closed.
- NVMe error cleanup fix from Jon Derrick, fixing a case where we'd
attempt to free an unregistered IRQ"
* 'for-linus' of git://git.kernel.dk/linux-block:
NVMe: Fix irq freeing when queue_request_irq fails
writeback: don't drain bdi_writeback_congested on bdi destruction
writeback: don't embed root bdi_writeback_congested in bdi_writeback
Nicolas Iooss [Mon, 29 Jun 2015 10:39:23 +0000 (18:39 +0800)]
KVM: x86: remove data variable from kvm_get_msr_common
Commit 609e36d372ad ("KVM: x86: pass host_initiated to functions that
read MSRs") modified kvm_get_msr_common function to use msr_info->data
instead of data but missed one occurrence. Replace it and remove the
unused local variable.
Fixes: 609e36d372ad ("KVM: x86: pass host_initiated to functions that
read MSRs") Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cornelia Huck [Mon, 29 Jun 2015 14:44:01 +0000 (16:44 +0200)]
KVM: s390: virtio-ccw: don't overwrite config space values
Eric noticed problems with vhost-scsi and virtio-ccw: vhost-scsi
complained about overwriting values in the config space, which
was triggered by a broken implementation of virtio-ccw's config
get/set routines. It was probably sheer luck that we did not hit
this before.
When writing a value to the config space, the WRITE_CONF ccw will
always write from the beginning of the config space up to and
including the value to be set. If the config space up to the value
has not yet been retrieved from the device, however, we'll end up
overwriting values. Keep track of the known config space and update
if needed to avoid this.
Moreover, READ_CONF will only read the number of bytes it has been
instructed to retrieve, so we must not copy more than that to the
buffer, or we might overwrite trailing values.
Reported-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Tested-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Radim Krčmář [Tue, 30 Jun 2015 20:19:16 +0000 (22:19 +0200)]
KVM: x86: keep track of LVT0 changes under APICv
Memory-mapped LVT0 register already contains the new value when APICv
traps so we can't directly detect a change.
Memorize a bit we are interested in to enable legacy NMI watchdog.
Suggested-by: Yoshida Nobuo <yoshida.nb@ncos.nec.co.jp> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Writes were a bit racy, but hard to turn into a bug at the same time.
(Particularly because modern Linux doesn't use this feature anymore.)
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[Actually the next patch makes it much, much easier to trigger the race
so I'm including this one for stable@ as well. - Paolo] Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Peter Zijlstra [Fri, 3 Jul 2015 16:53:58 +0000 (18:53 +0200)]
sched, preempt_notifier: separate notifier registration from static_key inc/dec
Commit 1cde2930e154 ("sched/preempt: Add static_key() to preempt_notifiers")
had two problems. First, the preempt-notifier API needs to sleep with the
addition of the static_key, we do however need to hold off preemption
while modifying the preempt notifier list, otherwise a preemption could
observe an inconsistent list state. KVM correctly registers and
unregisters preempt notifiers with preemption disabled, so the sleep
caused dmesg splats.
Second, KVM registers and unregisters preemption notifiers very often
(in vcpu_load/vcpu_put). With a single uniprocessor guest the static key
would move between 0 and 1 continuously, hitting the slow path on every
userspace exit.
To fix this, wrap the static_key inc/dec in a new API, and call it from
KVM.
Fixes: 1cde2930e154 ("sched/preempt: Add static_key() to preempt_notifiers") Reported-by: Pontus Fuchs <pontus.fuchs@gmail.com> Reported-by: Takashi Iwai <tiwai@suse.de> Tested-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 86dca36e6ba introduced ratelimited usage for
'unhandled_signal' messages.
The commit checks the ratelimit irrespective of whether
the signal is handled or not, which is wrong and leads
to false reports like the below in dmesg :
__do_user_fault: 127 callbacks suppressed
Do the ratelimit check only if the signal is unhandled.
Fixes: 86dca36e6ba0 ("arm64: use private ratelimit state along with show_unhandled_signals") Cc: Vladimir Murzin <Vladimir.Murzin@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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