This silently was working for many years and stopped working on
Niagara-T3 machines.
We need to set the MSIQ to VALID before we can set it's state to IDLE.
On Niagara-T3, setting the state to IDLE first was causing HV_EINVAL
errors. The hypervisor documentation says, rather ambiguously, that
the MSIQ must be "initialized" before one can set the state.
I previously understood this to mean merely that a successful setconf()
operation has been performed on the MSIQ, which we have done at this
point. But it seems to also mean that it has been set VALID too.
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: Fix usb/isp1760 build on sparc
usb: gadget: epautoconf: do not change number of streams
usb: dwc3: core: fix cached revision on our structure
usb: musb: fix reset issue with full speed device
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, the *_global_[un]lock_online() routines are not at all synchronized
with CPU hotplug. Soft-lockups detected as a consequence of this race was
reported earlier at https://lkml.org/lkml/2011/8/24/185. (Thanks to Cong Meng
for finding out that the root-cause of this issue is the race condition
between br_write_[un]lock() and CPU hotplug, which results in the lock states
getting messed up).
Fixing this race by just adding {get,put}_online_cpus() at appropriate places
in *_global_[un]lock_online() is not a good option, because, then suddenly
br_write_[un]lock() would become blocking, whereas they have been kept as
non-blocking all this time, and we would want to keep them that way.
So, overall, we want to ensure 3 things:
1. br_write_lock() and br_write_unlock() must remain as non-blocking.
2. The corresponding lock and unlock of the per-cpu spinlocks must not happen
for different sets of CPUs.
3. Either prevent any new CPU online operation in between this lock-unlock, or
ensure that the newly onlined CPU does not proceed with its corresponding
per-cpu spinlock unlocked.
To achieve all this:
(a) We introduce a new spinlock that is taken by the *_global_lock_online()
routine and released by the *_global_unlock_online() routine.
(b) We register a callback for CPU hotplug notifications, and this callback
takes the same spinlock as above.
(c) We maintain a bitmap which is close to the cpu_online_mask, and once it is
initialized in the lock_init() code, all future updates to it are done in
the callback, under the above spinlock.
(d) The above bitmap is used (instead of cpu_online_mask) while locking and
unlocking the per-cpu locks.
The callback takes the spinlock upon the CPU_UP_PREPARE event. So, if the
br_write_lock-unlock sequence is in progress, the callback keeps spinning,
thus preventing the CPU online operation till the lock-unlock sequence is
complete. This takes care of requirement (3).
The bitmap that we maintain remains unmodified throughout the lock-unlock
sequence, since all updates to it are managed by the callback, which takes
the same spinlock as the one taken by the lock code and released only by the
unlock routine. Combining this with (d) above, satisfies requirement (2).
Overall, since we use a spinlock (mentioned in (a)) to prevent CPU hotplug
operations from racing with br_write_lock-unlock, requirement (1) is also
taken care of.
By the way, it is to be noted that a CPU offline operation can actually run
in parallel with our lock-unlock sequence, because our callback doesn't react
to notifications earlier than CPU_DEAD (in order to maintain our bitmap
properly). And this means, since we use our own bitmap (which is stale, on
purpose) during the lock-unlock sequence, we could end up unlocking the
per-cpu lock of an offline CPU (because we had locked it earlier, when the
CPU was online), in order to satisfy requirement (2). But this is harmless,
though it looks a bit awkward.
Debugged-by: Cong Meng <mc@linux.vnet.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
net: Add a flow_cache_flush_deferred function
ipv4: reintroduce route cache garbage collector
net: have ipconfig not wait if no dev is available
sctp: Do not account for sizeof(struct sk_buff) in estimated rwnd
asix: new device id
davinci-cpdma: fix locking issue in cpdma_chan_stop
sctp: fix incorrect overflow check on autoclose
r8169: fix Config2 MSIEnable bit setting.
llc: llc_cmsg_rcv was getting called after sk_eat_skb.
net: bpf_jit: fix an off-one bug in x86_64 cond jump target
iwlwifi: update SCD BC table for all SCD queues
Revert "Bluetooth: Revert: Fix L2CAP connection establishment"
Bluetooth: Clear RFCOMM session timer when disconnecting last channel
Bluetooth: Prevent uninitialized data access in L2CAP configuration
iwlwifi: allow to switch to HT40 if not associated
iwlwifi: tx_sync only on PAN context
mwifiex: avoid double list_del in command cancel path
ath9k: fix max phy rate at rate control init
nfc: signedness bug in __nci_request()
iwlwifi: do not set the sequence control bit is not needed
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: atmel/ac97c: using software reset instead hardware reset if not available
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
mfd: Include linux/io.h to jz4740-adc
mfd: Use request_threaded_irq for twl4030-irq instead of irq_set_chained_handler
mfd: Base interrupt for twl4030-irq must be one-shot
mfd: Handle tps65910 clear-mask correctly
mfd: add #ifdef CONFIG_DEBUG_FS guard for ab8500_debug_resources
mfd: Fix twl-core oops while calling twl_i2c_* for unbound driver
mfd: include linux/module.h for ab5500-debugfs
mfd: Update wm8994 active device checks for WM1811
mfd: Set tps6586x bits if new value is different from the old one
mfd: Set da903x bits if new value is different from the old one
mfd: Set adp5520 bits if new value is different from the old one
mfd: Add missed free_irq in da903x_remove
lockdep reports a deadlock in jfs because a special inode's rw semaphore
is taken recursively. The mapping's gfp mask is GFP_NOFS, but is not
used when __read_cache_page() calls add_to_page_cache_lru().
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-greg' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb:
usb: gadget: epautoconf: do not change number of streams
usb: dwc3: core: fix cached revision on our structure
usb: musb: fix reset issue with full speed device
This commit:
commit 8f5d621543
Author: Joachim Foerster <joachim.foerster@missinglinkelectronics.com>
Date: Mon Oct 10 18:06:54 2011 +0200
usb/isp1760: Let OF bindings depend on general CONFIG_OF instead of PPC_OF .
To be able to use the driver on other OF-aware architectures, too.
And add necessary OF related #includes to fix compilation error.
Signed-off-by: Joachim Foerster <joachim.foerster@missinglinkelectronics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
enabled the build on all CONFIG_OF architectures, but it cannot do
this.
This driver depends upon CONFIG_OF_IRQ but not all CONFIG_OF platforms
support that infrastructure, in particular Sparc does not so the
build fails.
Please push a patch like the following to Linus so that this code only
gets built where it actually should.
--------------------
usb/isp1760: Add missing CONFIG_OF_IRQ dependency on OF code.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
flow_cach_flush() might sleep but can be called from
atomic context via the xfrm garbage collector. So add
a flow_cache_flush_deferred() function and use this if
the xfrm garbage colector is invoked from within the
packet path.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 2c8cec5c10 (ipv4: Cache learned PMTU information in inetpeer)
removed IP route cache garbage collector a bit too soon, as this gc was
responsible for expired routes cleanup, releasing their neighbour
reference.
As pointed out by Robert Gladewitz, recent kernels can fill and exhaust
their neighbour cache.
Reintroduce the garbage collection, since we'll have to wait our
neighbour lookups become refcount-less to not depend on this stuff.
Reported-by: Robert Gladewitz <gladewitz@gmx.de>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David and I are sharing maintenance of this repository. Patches
should be sent to both of us.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.infradead.org/mtd-2.6:
mtd: plat_ram: call mtd_device_register only if partition data exists
mtd: pxa2xx-flash.c: It used to fall back to provided table.
mtd: gpmi: add missing include 'module.h'
mtd: ndfc: fix typo in structure dereference
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time/clocksource: Fix kernel-doc warnings
rtc: m41t80: Workaround broken alarm functionality
rtc: Expire alarms after the time is set.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
oprofile: Fix uninitialized memory access when writing to writing to oprofilefs
* 'stable/for-linus-fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel"
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: Fix a regression in nfs_file_llseek()
NFSv4: Do not accept delegated opens when a delegation recall is in effect
NFSv4: Ensure correct locking when accessing the 'lock_states' list
NFSv4.1: Ensure that we handle _all_ SEQUENCE status bits.
NFSv4: Don't error if we handled it in nfs4_recovery_handle_error
SUNRPC: Ensure we always bump the backlog queue in xprt_free_slot
SUNRPC: Fix the execution time statistics in the face of RPC restarts
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
vmwgfx: Clip cliprects against screen boundaries in present and dirty
vmwgfx: Resend the cursor after legacy modeset
vmwgfx: Do better culling of presents
vmwgfx: Refactor kms code to use vmw_user_lookup_handle helper
vmwgfx: Add helper function to get surface or dmabuf
vmwgfx: Refactor cursor update
vmwgfx: Remove dmabuf check in present ioctl
vmwgfx: Use the revised fifo hw version register when present
previous commit 3fb72f1e6e
makes IP-Config wait for carrier on at least one network device.
Before waiting (predefined value 120s), check that at least one device
was successfully brought up. Otherwise (e.g. buggy bootloader
which does not set the MAC address) there is no point in waiting
for carrier.
Cc: Micha Nelissen <micha@neli.hopto.org>
Cc: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When checking whether a DATA chunk fits into the estimated rwnd a
full sizeof(struct sk_buff) is added to the needed chunk size. This
quickly exhausts the available rwnd space and leads to packets being
sent which are much below the PMTU limit. This can lead to much worse
performance.
The reason for this behaviour was to avoid putting too much memory
pressure on the receiver. The concept is not completely irational
because a Linux receiver does in fact clone an skb for each DATA chunk
delivered. However, Linux also reserves half the available socket
buffer space for data structures therefore usage of it is already
accounted for.
When proposing to change this the last time it was noted that this
behaviour was introduced to solve a performance issue caused by rwnd
overusage in combination with small DATA chunks.
Trying to reproduce this I found that with the sk_buff overhead removed,
the performance would improve significantly unless socket buffer limits
are increased.
The following numbers have been gathered using a patched iperf
supporting SCTP over a live 1 Gbit ethernet network. The -l option
was used to limit DATA chunk sizes. The numbers listed are based on
the average of 3 test runs each. Default values have been used for
sk_(r|w)mem.
Chunk
Size Unpatched No Overhead
-------------------------------------
4 15.2 Kbit [!] 12.2 Mbit [!]
8 35.8 Kbit [!] 26.0 Mbit [!]
16 95.5 Kbit [!] 54.4 Mbit [!]
32 106.7 Mbit 102.3 Mbit
64 189.2 Mbit 188.3 Mbit
128 331.2 Mbit 334.8 Mbit
256 537.7 Mbit 536.0 Mbit
512 766.9 Mbit 766.6 Mbit
1024 810.1 Mbit 808.6 Mbit
Signed-off-by: Thomas Graf <tgraf@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
binary_sysctl() calls sysctl_getname() which allocates from names_cache
slab usin __getname()
The matching function to free the name is __putname(), and not putname()
which should be used only to match getname() allocations.
This is because when auditing is enabled, putname() calls audit_putname
*instead* (not in addition) to __putname(). Then, if a syscall is in
progress, audit_putname does not release the name - instead, it expects
the name to get released when the syscall completes, but that will happen
only if audit_getname() was called previously, i.e. if the name was
allocated with getname() rather than the naked __getname(). So,
__getname() followed by putname() ends up leaking memory.
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Static storage is not required for the struct vmap_area in
__get_vm_area_node.
Removing "static" to store this variable on the stack instead.
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the BMC gets reset, it will return 0x80 response errors.
In less than a week
# grep "Error 80 on cmd 22" /var/log/kernel |wc -l
378681
In this case, it is probably a good idea to restore the IPMI settings.
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Tested-by: Arkadiusz Miśkiewicz <a.miskiewicz@gmail.com>
Reported-by: Arkadiusz Miśkiewicz <a.miskiewicz@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
An integer overflow will happen on 64bit archs if task's sum of rss,
swapents and nr_ptes exceeds (2^31)/1000 value. This was introduced by
commit
f755a04 oom: use pte pages in OOM score
where the oom score computation was divided into several steps and it's no
longer computed as one expression in unsigned long(rss, swapents, nr_pte
are unsigned long), where the result value assigned to points(int) is in
range(1..1000). So there could be an int overflow while computing
176 points *= 1000;
and points may have negative value. Meaning the oom score for a mem hog task
will be one.
196 if (points <= 0)
197 return 1;
For example:
[ 3366] 0 3366 35390480 24303939 5 0 0 oom01
Out of memory: Kill process 3366 (oom01) score 1 or sacrifice child
Here the oom1 process consumes more than 24303939(rss)*4096~=92GB physical
memory, but it's oom score is one.
In this situation the mem hog task is skipped and oom killer kills another and
most probably innocent task with oom score greater than one.
The points variable should be of type long instead of int to prevent the
int overflow.
Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org> [2.6.36+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the request is to create non-root group and we fail to meet it, we
should leave the root unchanged.
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a potential integer overflow in nilfs_ioctl_clean_segments().
When a large argv[n].v_nmembs is passed from the userspace, the subsequent
call to vmalloc() will allocate a buffer smaller than expected, which
leads to out-of-bound access in nilfs_ioctl_move_blocks() and
lfs_clean_segments().
The following check does not prevent the overflow because nsegs is also
controlled by the userspace and could be very large.
if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
goto out_free;
This patch clamps argv[n].v_nmembs to UINT_MAX / argv[n].v_size, and
returns -EINVAL when overflow.
Signed-off-by: Haogang Chen <haogangchen@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kernels where MAX_NUMNODES > BITS_PER_LONG may temporarily see an empty
nodemask in a tsk's mempolicy if its previous nodemask is remapped onto a
new set of allowed cpuset nodes where the two nodemasks, as a result of
the remap, are now disjoint.
c0ff7453bb ("cpuset,mm: fix no node to alloc memory when changing
cpuset's mems") adds get_mems_allowed() to prevent the set of allowed
nodes from changing for a thread. This causes any update to a set of
allowed nodes to stall until put_mems_allowed() is called.
This stall is unncessary, however, if at least one node remains unchanged
in the update to the set of allowed nodes. This was addressed by
89e8a244b9 ("cpusets: avoid looping when storing to mems_allowed if one
node remains set"), but it's still possible that an empty nodemask may be
read from a mempolicy because the old nodemask may be remapped to the new
nodemask during rebind. To prevent this, only avoid the stall if there is
no mempolicy for the thread being changed.
This is a temporary solution until all reads from mempolicy nodemasks can
be guaranteed to not be empty without the get_mems_allowed()
synchronization.
Also moves the check for nodemask intersection inside task_lock() so that
tsk->mems_allowed cannot change. This ensures that nothing can set this
tsk's mems_allowed out from under us and also protects tsk->mempolicy.
Reported-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Include linux/io.h to fix below build error:
CC drivers/mfd/jz4740-adc.o
drivers/mfd/jz4740-adc.c: In function 'jz4740_adc_irq_demux':
drivers/mfd/jz4740-adc.c:73: error: implicit declaration of function 'readb'
drivers/mfd/jz4740-adc.c: In function 'jz4740_adc_set_enabled':
drivers/mfd/jz4740-adc.c:110: error: implicit declaration of function 'writeb'
drivers/mfd/jz4740-adc.c: In function 'jz4740_adc_set_config':
drivers/mfd/jz4740-adc.c:146: error: implicit declaration of function 'readl'
drivers/mfd/jz4740-adc.c:151: error: implicit declaration of function 'writel'
drivers/mfd/jz4740-adc.c: In function 'jz4740_adc_probe':
drivers/mfd/jz4740-adc.c:249: error: implicit declaration of function 'ioremap_nocache'
drivers/mfd/jz4740-adc.c:249: warning: assignment makes pointer from integer without a cast
drivers/mfd/jz4740-adc.c:289: warning: passing argument 3 of 'mfd_add_devices' discards qualifiers from pointer target type
include/linux/mfd/core.h:93: note: expected 'struct mfd_cell *' but argument is of type 'const struct mfd_cell *'
drivers/mfd/jz4740-adc.c:299: error: implicit declaration of function 'iounmap'
make[2]: *** [drivers/mfd/jz4740-adc.o] Error 1
make[1]: *** [drivers/mfd] Error 2
make: *** [drivers] Error 2
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
irq_set_chained_handler sets 'desc->handle_irq'.
However this irq is called by handle_nested_irq from handle_twl4030_pih,
and that uses action->thread_fn.
So the handled set with irq_set_chained_handler is never called.
So change to use request_threaded_irq instead - that sets the correct field.
Tested on GTA04 Phoenux.
Signed-off-by: NeilBrown <neilb@suse.de>
Tested-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
As the interrupt source is only cleared by the threaded interrupt
service routine, we need to make the base interrupt IRQF_ONESHOT.
Without this, the first interrupt from the TWL4030 cause the CPU to
enter an infinite loop trying to handle to interrupt but never
clearing it.
Signed-off-by: NeilBrown <neilb@suse.de>
Tested-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The function is not actually cleaing the bitmask.
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Fix below build warning if CONFIG_DEBUG_FS is disabled.
CC drivers/mfd/ab8500-core.o
drivers/mfd/ab8500-core.c:623: warning: 'ab8500_debug_resources' defined but not used
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Check inuse variable before trying to access twl_map to prevent
dereferencing of uninitialized variable.
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Cc: stable@kernel.org
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Include linux/module.h to fix below build error:
CC drivers/mfd/ab5500-debugfs.o
drivers/mfd/ab5500-debugfs.c:571: error: 'THIS_MODULE' undeclared here (not in a function)
make[2]: *** [drivers/mfd/ab5500-debugfs.o] Error 1
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This didn't go in as part of the original MFD patch for WM1811 due to
cross tree issues.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
It does not make sense to write new value only when all the bit_mask
bits are zero.
We need to write new value if the bit mask fields of new value is
not equal to old value.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
It does not make sense to write new value only when all the bit_mask
bits are zero.
We need to write new value if the bit mask fields of new value is
not equal to old value.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>