We try to linearize part of the skb when the number of iov is greater than
MAX_SKB_FRAGS. This is not enough since each single vector may occupy more than
one pages, so zerocopy_sg_fromiovec() may still fail and may break the guest
network.
Solve this problem by calculate the pages needed for iov before trying to do
zerocopy and switch to use copy instead of zerocopy if it needs more than
MAX_SKB_FRAGS.
This is done through introducing a new helper to count the pages for iov, and
call uarg->callback() manually when switching from zerocopy to copy to notify
vhost.
We can do further optimization on top.
This bug were introduced from b92946e291
(macvtap: zerocopy: validate vectors before building skb).
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We try to linearize part of the skb when the number of iov is greater than
MAX_SKB_FRAGS. This is not enough since each single vector may occupy more than
one pages, so zerocopy_sg_fromiovec() may still fail and may break the guest
network.
Solve this problem by calculate the pages needed for iov before trying to do
zerocopy and switch to use copy instead of zerocopy if it needs more than
MAX_SKB_FRAGS.
This is done through introducing a new helper to count the pages for iov, and
call uarg->callback() manually when switching from zerocopy to copy to notify
vhost.
We can do further optimization on top.
The bug were introduced from commit 0690899b4d
(tun: experimental zero copy tx support)
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
QFQ+ inherits from QFQ a design choice that may cause a high packet
delay/jitter and a severe short-term unfairness. As QFQ, QFQ+ uses a
special quantity, the system virtual time, to track the service
provided by the ideal system it approximates. When a packet is
dequeued, this quantity must be incremented by the size of the packet,
divided by the sum of the weights of the aggregates waiting to be
served. Tracking this sum correctly is a non-trivial task, because, to
preserve tight service guarantees, the decrement of this sum must be
delayed in a special way [1]: this sum can be decremented only after
that its value would decrease also in the ideal system approximated by
QFQ+. For efficiency, QFQ+ keeps track only of the 'instantaneous'
weight sum, increased and decreased immediately as the weight of an
aggregate changes, and as an aggregate is created or destroyed (which,
in its turn, happens as a consequence of some class being
created/destroyed/changed). However, to avoid the problems caused to
service guarantees by these immediate decreases, QFQ+ increments the
system virtual time using the maximum value allowed for the weight
sum, 2^10, in place of the dynamic, instantaneous value. The
instantaneous value of the weight sum is used only to check whether a
request of weight increase or a class creation can be satisfied.
Unfortunately, the problems caused by this choice are worse than the
temporary degradation of the service guarantees that may occur, when a
class is changed or destroyed, if the instantaneous value of the
weight sum was used to update the system virtual time. In fact, the
fraction of the link bandwidth guaranteed by QFQ+ to each aggregate is
equal to the ratio between the weight of the aggregate and the sum of
the weights of the competing aggregates. The packet delay guaranteed
to the aggregate is instead inversely proportional to the guaranteed
bandwidth. By using the maximum possible value, and not the actual
value of the weight sum, QFQ+ provides each aggregate with the worst
possible service guarantees, and not with service guarantees related
to the actual set of competing aggregates. To see the consequences of
this fact, consider the following simple example.
Suppose that only the following aggregates are backlogged, i.e., that
only the classes in the following aggregates have packets to transmit:
one aggregate with weight 10, say A, and ten aggregates with weight 1,
say B1, B2, ..., B10. In particular, suppose that these aggregates are
always backlogged. Given the weight distribution, the smoothest and
fairest service order would be:
A B1 A B2 A B3 A B4 A B5 A B6 A B7 A B8 A B9 A B10 A B1 A B2 ...
QFQ+ would provide exactly this optimal service if it used the actual
value for the weight sum instead of the maximum possible value, i.e.,
11 instead of 2^10. In contrast, since QFQ+ uses the latter value, it
serves aggregates as follows (easy to prove and to reproduce
experimentally):
A B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 A A A A A A A A A A B1 B2 ... B10 A A ...
By replacing 10 with N in the above example, and by increasing N, one
can increase at will the maximum packet delay and the jitter
experienced by the classes in aggregate A.
This patch addresses this issue by just using the above
'instantaneous' value of the weight sum, instead of the maximum
possible value, when updating the system virtual time. After the
instantaneous weight sum is decreased, QFQ+ may deviate from the ideal
service for a time interval in the order of the time to serve one
maximum-size packet for each backlogged class. The worst-case extent
of the deviation exhibited by QFQ+ during this time interval [1] is
basically the same as of the deviation described above (but, without
this patch, QFQ+ suffers from such a deviation all the time). Finally,
this patch modifies the comment to the function qfq_slot_insert, to
make it coherent with the fact that the weight sum used by QFQ+ can
now be lower than the maximum possible value.
[1] P. Valente, "Extending WF2Q+ to support a dynamic traffic mix",
Proceedings of AAA-IDEA'05, June 2005.
Signed-off-by: Paolo Valente <paolo.valente@unimore.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
Here are some driver core patches for 3.11-rc2. They aren't really
bugfixes, but a bunch of new helper macros for drivers to properly
create attribute groups, which drivers and subsystems need to fix up a
ton of race issues with incorrectly creating sysfs files (binary and
normal) after userspace has been told that the device is present.
Also here is the ability to create binary files as attribute groups, to
solve that race condition, which was impossible to do before this, so
that's my fault the drivers were broken.
The majority of the .c changes is indenting and moving code around a
bit. It affects no existing code, but allows the large backlog of 70+
patches that I already have created to start flowing into the different
subtrees, instead of having to live in my driver-core tree, causing
merge nightmares in linux-next for the next few months.
These were finalized too late for the -rc1 merge window, which is why
they were didn't make that pull request, testing and review from others
didn't happen until a few weeks ago, and then there's the whole
distraction of the past few days, which prevented these from getting to
you sooner, sorry about that.
Oh, and there's a bugfix for the documentation build warning in here as
well. All of these have been in linux-next this week, with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core patches from Greg KH:
"Here are some driver core patches for 3.11-rc2. They aren't really
bugfixes, but a bunch of new helper macros for drivers to properly
create attribute groups, which drivers and subsystems need to fix up a
ton of race issues with incorrectly creating sysfs files (binary and
normal) after userspace has been told that the device is present.
Also here is the ability to create binary files as attribute groups,
to solve that race condition, which was impossible to do before this,
so that's my fault the drivers were broken.
The majority of the .c changes is indenting and moving code around a
bit. It affects no existing code, but allows the large backlog of 70+
patches that I already have created to start flowing into the
different subtrees, instead of having to live in my driver-core tree,
causing merge nightmares in linux-next for the next few months.
These were finalized too late for the -rc1 merge window, which is why
they were didn't make that pull request, testing and review from
others didn't happen until a few weeks ago, and then there's the whole
distraction of the past few days, which prevented these from getting
to you sooner, sorry about that.
Oh, and there's a bugfix for the documentation build warning in here
as well. All of these have been in linux-next this week, with no
reported problems"
* tag 'driver-core-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
driver-core: fix new kernel-doc warning in base/platform.c
sysfs: use file mode defines from stat.h
sysfs: add more helper macro's for (bin_)attribute(_groups)
driver core: add default groups to struct class
driver core: Introduce device_create_groups
sysfs: prevent warning when only using binary attributes
sysfs: add support for binary attributes in groups
driver core: device.h: add RW and RO attribute macros
sysfs.h: add BIN_ATTR macro
sysfs.h: add ATTRIBUTE_GROUPS() macro
sysfs.h: add __ATTR_RW() macro
* acpi-fixes:
ACPI / video: ignore BIOS initial backlight value for Fujitsu E753
PNP / ACPI: avoid garbage in resource name
ACPI / memhotplug: Fix a stale pointer in error path
ACPI / scan: Always call acpi_bus_scan() for bus check notifications
ACPI / scan: Do not try to attach scan handlers to devices having them
The BIOS of FUjitsu E753 reports an incorrect initial backlight value
for WIN8 compatible OS, causing backlight to be dark during startup.
This change causes the incorrect initial value from BIOS to be ignored.
References: https://bugzilla.kernel.org/show_bug.cgi?id=60161
Reported-and-tested-by: Jan Hinnerk Stosch <janhinnerk.stosch@gmail.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Cc: 3.7+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull phase two of __cpuinit removal from Paul Gortmaker:
"With the __cpuinit infrastructure removed earlier, this group of
commits only removes the function/data tagging that was done with the
various (now no-op) __cpuinit related prefixes.
Now that the dust has settled with yesterday's v3.11-rc1, there
hopefully shouldn't be any new users leaking back in tree, but I think
we can leave the harmless no-op stubs there for a release as a
courtesy to those who still have out of tree stuff and weren't paying
attention.
Although the commits are against the recent tag to allow for minor
context refreshes for things like yesterday's v3.11-rc1~ slab content,
the patches have been largely unchanged for weeks, aside from such
trivial updates.
For detail junkies, the largely boring and mostly irrelevant history
of the patches can be viewed at:
http://git.kernel.org/cgit/linux/kernel/git/paulg/cpuinit-delete.git
If nothing else, I guess it does at least demonstrate the level of
involvement required to shepherd such a treewide change to completion.
This is the same repository of patches that has been applied to the
end of the daily linux-next branches for the past several weeks"
* 'cpuinit_phase2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (28 commits)
block: delete __cpuinit usage from all block files
drivers: delete __cpuinit usage from all remaining drivers files
kernel: delete __cpuinit usage from all core kernel files
rcu: delete __cpuinit usage from all rcu files
net: delete __cpuinit usage from all net files
acpi: delete __cpuinit usage from all acpi files
hwmon: delete __cpuinit usage from all hwmon files
cpufreq: delete __cpuinit usage from all cpufreq files
clocksource+irqchip: delete __cpuinit usage from all related files
x86: delete __cpuinit usage from all x86 files
score: delete __cpuinit usage from all score files
xtensa: delete __cpuinit usage from all xtensa files
openrisc: delete __cpuinit usage from all openrisc files
m32r: delete __cpuinit usage from all m32r files
hexagon: delete __cpuinit usage from all hexagon files
frv: delete __cpuinit usage from all frv files
cris: delete __cpuinit usage from all cris files
metag: delete __cpuinit usage from all metag files
tile: delete __cpuinit usage from all tile files
sh: delete __cpuinit usage from all sh files
...
Except for a slightly big OMAP changes, all rest are small, mostly
boring changes; all either 3.11 regression fixes or stable materials.
- ASoC OMAP fixes due to non-DT OMAP4 removals
- Other ASoC driver changes (sglt5000, wm8978, wm8948, samsung)
- Fix missing locking for snd_pcm_stop() calls in many drivers
- Fix the blocking request_module() in OSS sequencer
- Fix old OSS vwsnd driver builds
- Add a new HD-audio HDMI codec ID
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Merge tag 'sound-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Except for a slightly big OMAP changes, all rest are small, mostly
boring changes; all either 3.11 regression fixes or stable materials.
- ASoC OMAP fixes due to non-DT OMAP4 removals
- Other ASoC driver changes (sglt5000, wm8978, wm8948, samsung)
- Fix missing locking for snd_pcm_stop() calls in many drivers
- Fix the blocking request_module() in OSS sequencer
- Fix old OSS vwsnd driver builds
- Add a new HD-audio HDMI codec ID"
* tag 'sound-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (23 commits)
ALSA: seq-oss: Initialize MIDI clients asynchronously
ALSA: hda - Add new GPU codec ID to snd-hda
staging: line6: Fix unlocked snd_pcm_stop() call
[media] saa7134: Fix unlocked snd_pcm_stop() call
ASoC: s6000: Fix unlocked snd_pcm_stop() call
ASoC: atmel: Fix unlocked snd_pcm_stop() call
ALSA: pxa2xx: Fix unlocked snd_pcm_stop() call
ALSA: usx2y: Fix unlocked snd_pcm_stop() call
ALSA: ua101: Fix unlocked snd_pcm_stop() call
ALSA: 6fire: Fix unlocked snd_pcm_stop() call
ALSA: atiixp: Fix unlocked snd_pcm_stop() call
ALSA: asihpi: Fix unlocked snd_pcm_stop() call
sound: oss/vwsnd: Always define vwsnd_mutex
sound: oss/vwsnd: Add missing inclusion of linux/delay.h
ASoC: wm8978: enable symmetric rates
ASoC: omap-mcbsp: Use different method for DMA request when booted with DT
ASoC: omap-dmic: Do not use platform_get_resource_byname() for DMA
ASoC: omap-mcpdm: Do not use platform_get_resource_byname() for DMA
ASoC: omap-pcm: Request the DMA channel differently when DT is involved
ASoC: Samsung: Set RFS and BFS in slave mode
...
The kdump mmap patch series (git commit 83086978c6) changed the
requirements for copy_oldmem_page(). Now this function is used for copying
to virtual memory.
So implement vmalloc support for the s390 version of copy_oldmem_page().
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kdump mmap patch series (git commit 83086978c6) directly
map the PT_LOADs to memory. On s390 this does not work because the
copy_from_oldmem() function swaps [0,crashkernel size] with
[crashkernel base, crashkernel base+crashkernel size]. The swap
int copy_from_oldmem() was done in order correctly implement /dev/oldmem.
See: http://marc.info/?l=kexec&m=136940802511603&w=2
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This is the s390 variant of 314beb9b "x86: bpf_jit_comp: secure bpf
jit against spraying attacks".
With this change the whole jit code and literal pool will be write
protected after creation. In addition the start address of the jit
code won't be always on a page boundary anymore.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This is the s390 backend of 79617801 "filter: bpf_jit_comp: refactor
and unify BPF JIT image dump output".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The workqueue workaround is no longer needed. Same as 5199dfe531
"sparc: bpf_jit_comp: can call module_free() from any context".
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently, fast page fault incorrectly tries to fix mmio page fault when
the generation number is invalid (spte.gen != kvm.gen). It then returns
to guest to retry the fault since it sees the last spte is nonpresent.
This causes an infinite loop.
Since fast page fault only works for direct mmu, the issue exists when
1) tdp is enabled. It is only triggered only on AMD host since on Intel host
the mmio page fault is recognized as ept-misconfig whose handler call
fault-page path with error_code = 0
2) guest paging is disabled. Under this case, the issue is hardly discovered
since paging disable is short-lived and the sptes will be invalid after
memslot changed for 150 times
Fix it by filtering out MMIO page faults in page_fault_can_be_fast.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Recent change to use bio_copy_data() in raid1 when repairing
an array is faulty.
The underlying may have changed the bio in various ways using
bio_advance and these need to be undone not just for the 'sbio' which
is being copied to, but also the 'pbio' (primary) which is being
copied from.
So perform the reset on all bios that were read from and do it early.
This also ensure that the sbio->bi_io_vec[j].bv_len passed to
memcmp is correct.
This fixes a crash during a 'check' of a RAID1 array. The crash was
introduced in 3.10 so this is suitable for 3.10-stable.
Cc: stable@vger.kernel.org (3.10)
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit 7ceb17e87b
md: Allow devices to be re-added to a read-only array.
allowed a bit more than just that. It also allows devices to be added
to a read-write array and to end up skipping recovery.
This patch removes the offending piece of code pending a rewrite for a
subsequent release.
More specifically:
If the array has a bitmap, then the device will still need a bitmap
based resync ('saved_raid_disk' is set under different conditions
is a bitmap is present).
If the array doesn't have a bitmap, then this is correct as long as
nothing has been written to the array since the metadata was checked
by ->validate_super. However there is no locking to ensure that there
was no write.
Bug was introduced in 3.10 and causes data corruption so
patch is suitable for 3.10-stable.
Cc: stable@vger.kernel.org (3.10)
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
1/ When an different between blocks is found, data is copied from
one bio to the other. However bv_len is used as the length to
copy and this could be zero. So use r10_bio->sectors to calculate
length instead.
Using bv_len was probably always a bit dubious, but the introduction
of bio_advance made it much more likely to be a problem.
2/ When preparing some blocks for sync, we don't set BIO_UPTODATE
except on bios that we schedule for a read. This ensures that
missing/failed devices don't confuse the loop at the top of
sync_request write.
Commit 8be185f2c9 "raid10: Use bio_reset()"
removed a loop which set BIO_UPTDATE on all appropriate bios.
So we need to re-add that flag.
These bugs were introduced in 3.10, so this patch is suitable for
3.10-stable, and can remove a potential for data corruption.
Cc: stable@vger.kernel.org (3.10)
Reported-by: Brassow Jonathan <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
more DPM fixes for radeon.
* 'drm-fixes-3.11' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon/dpm: add debugfs support for RS780/RS880 (v3)
drm/radeon/dpm/atom: fix broken gcc harder
drm/radeon/dpm/atom: restructure logic to work around a compiler bug
drm/radeon/dpm: fix atom vram table parsing
drm/radeon: fix an endian bug in atom table parsing
drm/radeon: add a module parameter to disable aspm
Starting from win8, MS backlight control driver will set bit 2 of the
parameter of control method _DOS, to inform firmware it should not
perform any automatic brightness changes. This mostly affects hotkey
notification deliver - if we do not set this bit, on hotkey press,
firmware may choose to adjust brightness level instead of sending out
notification and doing nothing.
So this patch sets bit 2 when calling _DOS so that GUIs can show the
notification window on hotkey press. This behavior change is only
necessary for win8 systems.
The MS document on win8 backlight control is here:
http://msdn.microsoft.com/en-US/library/windows/hardware/jj159305
References: https://bugzilla.kernel.org/show_bug.cgi?id=52951
References: https://bugzilla.kernel.org/show_bug.cgi?id=56711
Reported-by: Micael Dias <kam1kaz3@gmail.com>
Reported-by: Dan Garton <dan.garton@gmail.com>
Reported-by: Bob Ziuchkovski <bob.ziuchkovski@gmail.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to Matthew Garrett, "Windows 8 leaves backlight control up
to individual graphics drivers rather than making ACPI calls itself.
There's plenty of evidence to suggest that the Intel driver for
Windows [8] doesn't use the ACPI interface, including the fact that
it's broken on a bunch of machines when the OS claims to support
Windows 8. The simplest thing to do appears to be to disable the
ACPI backlight interface on these systems".
There's a problem with that approach, however, because simply
avoiding to register the ACPI backlight interface if the firmware
calls _OSI for Windows 8 may not work in the following situations:
(1) The ACPI backlight interface actually works on the given system
and the i915 driver is not loaded (e.g. another graphics driver
is used).
(2) The ACPI backlight interface doesn't work on the given system,
but there is a vendor platform driver that will register its
own, equally broken, backlight interface if not prevented from
doing so by the ACPI subsystem.
Therefore we need to allow the ACPI backlight interface to be
registered until the i915 driver is loaded which then will unregister
it if the firmware has called _OSI for Windows 8 (or will register
the ACPI video driver without backlight support if not already
present).
For this reason, introduce an alternative function for registering
ACPI video, acpi_video_register_with_quirks(), that will check
whether or not the ACPI video driver has already been registered
and whether or not the backlight Windows 8 quirk has to be applied.
If the quirk has to be applied, it will block the ACPI backlight
support and either unregister the backlight interface if the ACPI
video driver has already been registered, or register the ACPI
video driver without the backlight interface otherwise. Make
the i915 driver use acpi_video_register_with_quirks() instead of
acpi_video_register() in i915_driver_load().
This change is based on earlier patches from Matthew Garrett,
Chun-Yi Lee and Seth Forshee and includes a fix from Aaron Lu's.
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231
Tested-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
Tested-by: Yves-Alexis Perez <corsac@debian.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Matthew Garrett <matthew.garrett@nebula.com>
Set temporary variable as 0 to avoid garbage string output from
/proc/iomem after register resources and reset to PNP dev name
later.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We have to call acpi_video_init_brightness() even if we're not going
to initialise the backlight - Thinkpads seem to use this as the
trigger for enabling ACPI notifications rather than handling it in
firmware.
[rjw: Drop the brightness object created by
acpi_video_init_brightness() if we are not going to use it.]
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Expose acpi_gbl_osi_data so that code outside of ACPICA can check
the value of the last successfull _OSI call. The definitions for
OSI versions are moved to actypes.h so that other components can
access them too.
Based on a patch from Matthew Garrett which in turn was based on
an earlier patch from Seth Forshee.
[rjw: Changelog]
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Technically, the Linux client is allowed by the NFSv4 spec to send
3 word bitmaps as part of an OPEN request. However, this causes the
current FreeBSD server to return NFS4ERR_ATTRNOTSUPP errors.
Fix the regression by making the Linux client use a 2 word bitmap unless
doing NFSv4.2 with labeled NFS.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This allows you to look at the current DPM state via
debugfs.
Due to the way the hardware works on these asics, there's
no way to look up exactly what power state we are in, so
we make the best guess we can based on the current sclk.
v2: Anthoine's version
v3: fix ref div
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Pull nfsd bugfixes from Bruce Fields:
"Just three minor bugfixes"
* 'for-3.11' of git://linux-nfs.org/~bfields/linux:
svcrdma: underflow issue in decode_write_list()
nfsd4: fix minorversion support interface
lockd: protect nlm_blocked access in nlmsvc_retry_blocked
Due to commit 3683243b ("xen-netfront: use __pskb_pull_tail to ensure
linear area is big enough on RX") xennet_fill_frags() may end up
filling MAX_SKB_FRAGS + 1 fragments in a receive skb, and only reduce
the fragment count subsequently via __pskb_pull_tail(). That's a
result of xennet_get_responses() allowing a maximum of one more slot to
be consumed (and intermediately transformed into a fragment) if the
head slot has a size less than or equal to RX_COPY_THRESHOLD.
Hence we need to adjust xennet_fill_frags() to pull earlier if we
reached the maximum fragment count - due to the described behavior of
xennet_get_responses() this guarantees that at least the first fragment
will get completely consumed, and hence the fragment count reduced.
In order to not needlessly call __pskb_pull_tail() twice, make the
original call conditional upon the pull target not having been reached
yet, and defer the newly added one as much as possible (an alternative
would have been to always call the function right before the call to
xennet_fill_frags(), but that would imply more frequent cases of
needing to call it twice).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: stable@vger.kernel.org (3.6 onwards)
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The socket management is now done in workqueue (outside of RTNL)
and protected by vn->sock_lock. There were two possible bugs, first
the vxlan device was removed from the VNI hash table per socket without
holding lock. And there was a race when device is created and the workqueue
could run after deletion.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
panic() doesn't return so this call was useless.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
The GEM CMA PRIME import/export helpers have been removed in favor of
generic GEM PRIME helpers with GEM CMA low-level operations. Fix the
driver accordingly.
Reported-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Mark Brown <broonie@linaro.org>
The GEM CMA PRIME import/export helpers have been removed in favor of
generic GEM PRIME helpers with GEM CMA low-level operations. Fix the
driver accordingly.
Reported-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Mark Brown <broonie@linaro.org>
We've got bug reports that the module loading stuck on Debian system
with 3.10 kernel. The debugging session revealed that the initial
registration of OSS sequencer clients stuck at module loading time,
which involves again with request_module() at the init phase. This is
triggered only by special --install stuff Debian is using, but it's
still not good to have such loops.
As a workaround, call the registration part asynchronously. This is a
better approach irrespective of the hang fix, in anyway.
Reported-and-tested-by: Philipp Matthias Hahn <pmhahn@pmhahn.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
SG mode is not currently supported by netvsc, so remove this flag for now.
Otherwise, it will be unconditionally enabled by commit ec5f061564
"Kill link between CSUM and SG features"
Previously, the SG feature is disabled because CSUM is not set here.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix new kernel-doc warning in drivers/base/platform.c:
Warning(drivers/base/platform.c:528): No description found for parameter 'owner'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This set is larger than I would like, partly due to my lack of review
time in the weeks before the merge window and partly because a
couple of large drivers and the subsystem as a whole seem to be
getting a lot more exposure and testing recently.
1) A long term bug in trigger handling gave a double free of the device.
2) Wrong return value handling means offsets are ignored in
iio_convert_raw_to_processed_unlocked.
3) The iio_channel_has_info utility function was incorrectly updated
during the recent info_mask split, this is now fixed.
4) mxs-lradc has a couple of little fixes.
5) A couple of missing .driver_module entries meant that drivers
could be removed from underneath their users.
6) Error path fixes for ad7303 and lis3l02dq.
7) The scale value for presure in the lps331ap driver was out by
a factor of 100.
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Merge tag 'iio-fixes-for-3.11a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus
Jonathan writes:
The first round of IIO fixes for the 3.11 cycle.
This set is larger than I would like, partly due to my lack of review
time in the weeks before the merge window and partly because a
couple of large drivers and the subsystem as a whole seem to be
getting a lot more exposure and testing recently.
1) A long term bug in trigger handling gave a double free of the device.
2) Wrong return value handling means offsets are ignored in
iio_convert_raw_to_processed_unlocked.
3) The iio_channel_has_info utility function was incorrectly updated
during the recent info_mask split, this is now fixed.
4) mxs-lradc has a couple of little fixes.
5) A couple of missing .driver_module entries meant that drivers
could be removed from underneath their users.
6) Error path fixes for ad7303 and lis3l02dq.
7) The scale value for presure in the lps331ap driver was out by
a factor of 100.
This driver is not being updated as the specifications are not able to
be gotten from CSR or anyone else. Without those, getting this driver
into proper mergable shape is going to be impossible. So remove the
driver from the tree.
If the specifications ever become available, this patch can be reverted
and the driver fixed up properly.
Reported-by: Lidza Louina <lidza.louina@gmail.com>
Cc: Veli-Pekka Peltola <veli-pekka.peltola@bluegiga.com>
Cc: Mikko Virkkilä <mikko.virkkila@bluegiga.com>
Cc: Lauri Hintsala <Lauri.Hintsala@bluegiga.com>
Cc: Riku Mettälä <riku.mettala@bluegiga.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__list_for_each used to be the non prefetch() aware list walking
primitive. When we removed the prefetch macros from the list routines,
it became redundant. Given it does exactly the same thing as
list_for_each now, we might as well remove it and call list_for_each
directly.
All users of __list_for_each have been converted to list_for_each calls
in the current merge window.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's just a duplicate implementation of "%*phC". Thanks to Joe
Perches for showing that we had exactly this support in the
lib/vsprintf.c code already.
Signed-off-by: David S. Miller <davem@davemloft.net>
One feature latecomer, I've forgotten to merge the patch to reeanble the
Haswell power well feature now that the audio interaction is fixed up.
Since that was the only unfixed issue with it I've figured I could throw
it in a bit late, and it's trivial to revert in case I'm wrong.
Otherwise all bug/regression fixes:
- Fix status page reinit after gpu hangs, spotted by more paranoid igt
checks.
- Fix object list walking fumble regression in the shrinker (only the
counting part, the actual shrinking code was correct so no Oops
potential), from Xiong Zhang.
- Fix DP 1.2 bw limits (Imre).
- Restore legacy forcewake on ivb, too many broken biosen out there. We
dump a warn though that recent userspace might fall over with that
config (Guenter Roeck).
- Patch up the gen2 cs tlb w/a.
- Improve the fence coherency w/a now that we have a better understanding
what's going on. The removed wbinvd+ipi should make -rt folks happy. Big
thanks to Jon Bloomfield for figuring this out, patches from Chris.
- Fix write-read race when switching ring (Chris). Spotted with code
inspection, but now we also have an igt for it.
There's an ugly regression we're still working on introduced between
3.10-rc7 and 3.10.0. Unfortunately we can't just revert the offender since
that one fixes another regression :( I've asked Steven to include my
-fixes branch into linux-next to prevent such fallout in the future,
hopefully.
* tag 'drm-intel-fixes-2013-07-11' of git://people.freedesktop.org/~danvet/drm-intel:
Revert "drm/i915: Workaround incoherence between fences and LLC across multiple CPUs"
drm/i915: Fix incoherence with fence updates on Sandybridge+
drm/i915: Fix write-read race with multiple rings
Partially revert "drm/i915: unconditionally use mt forcewake on hsw/ivb"
drm/i915: fix lane bandwidth capping for DP 1.2 sinks
drm/i915: fix up ring cleanup for the i830/i845 CS tlb w/a
drm/i915: Correct obj->mm_list link to dev_priv->dev_priv->mm.inactive_list
drm/i915: switch disable_power_well default value to 1
drm/i915: reinit status page registers after gpu reset
Since the IDT is referenced from a fixmap, make sure it is page aligned.
Merge with 32-bit one, since it was already aligned to deal with F00F
bug. Since bss is cleared before IDT setup, it can live there. This also
moves the other *_idt_table variables into common locations.
This avoids the risk of the IDT ever being moved in the bss and having
the mapping be offset, resulting in calling incorrect handlers. In the
current upstream kernel this is not a manifested bug, but heavily patched
kernels (such as those using the PaX patch series) did encounter this bug.
The tables other than idt_table technically do not need to be page
aligned, at least not at the current time, but using a common
declaration avoids mistakes. On 64 bits the table is exactly one page
long, anyway.
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20130716183441.GA14232@www.outflux.net
Reported-by: PaX Team <pageexec@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
commit 2f7021a8 "cpufreq: protect 'policy->cpus' from offlining
during __gov_queue_work()" caused a regression in CPU hotplug,
because it lead to a deadlock between cpufreq governor worker thread
and the CPU hotplug writer task.
Lockdep splat corresponding to this deadlock is shown below:
[ 60.277396] ======================================================
[ 60.277400] [ INFO: possible circular locking dependency detected ]
[ 60.277407] 3.10.0-rc7-dbg-01385-g241fd04-dirty #1744 Not tainted
[ 60.277411] -------------------------------------------------------
[ 60.277417] bash/2225 is trying to acquire lock:
[ 60.277422] ((&(&j_cdbs->work)->work)){+.+...}, at: [<ffffffff810621b5>] flush_work+0x5/0x280
[ 60.277444] but task is already holding lock:
[ 60.277449] (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81042d8b>] cpu_hotplug_begin+0x2b/0x60
[ 60.277465] which lock already depends on the new lock.
[ 60.277472] the existing dependency chain (in reverse order) is:
[ 60.277477] -> #2 (cpu_hotplug.lock){+.+.+.}:
[ 60.277490] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[ 60.277503] [<ffffffff815b6157>] mutex_lock_nested+0x67/0x410
[ 60.277514] [<ffffffff81042cbc>] get_online_cpus+0x3c/0x60
[ 60.277522] [<ffffffff814b842a>] gov_queue_work+0x2a/0xb0
[ 60.277532] [<ffffffff814b7891>] cs_dbs_timer+0xc1/0xe0
[ 60.277543] [<ffffffff8106302d>] process_one_work+0x1cd/0x6a0
[ 60.277552] [<ffffffff81063d31>] worker_thread+0x121/0x3a0
[ 60.277560] [<ffffffff8106ae2b>] kthread+0xdb/0xe0
[ 60.277569] [<ffffffff815bb96c>] ret_from_fork+0x7c/0xb0
[ 60.277580] -> #1 (&j_cdbs->timer_mutex){+.+...}:
[ 60.277592] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[ 60.277600] [<ffffffff815b6157>] mutex_lock_nested+0x67/0x410
[ 60.277608] [<ffffffff814b785d>] cs_dbs_timer+0x8d/0xe0
[ 60.277616] [<ffffffff8106302d>] process_one_work+0x1cd/0x6a0
[ 60.277624] [<ffffffff81063d31>] worker_thread+0x121/0x3a0
[ 60.277633] [<ffffffff8106ae2b>] kthread+0xdb/0xe0
[ 60.277640] [<ffffffff815bb96c>] ret_from_fork+0x7c/0xb0
[ 60.277649] -> #0 ((&(&j_cdbs->work)->work)){+.+...}:
[ 60.277661] [<ffffffff810ab826>] __lock_acquire+0x1766/0x1d30
[ 60.277669] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[ 60.277677] [<ffffffff810621ed>] flush_work+0x3d/0x280
[ 60.277685] [<ffffffff81062d8a>] __cancel_work_timer+0x8a/0x120
[ 60.277693] [<ffffffff81062e53>] cancel_delayed_work_sync+0x13/0x20
[ 60.277701] [<ffffffff814b89d9>] cpufreq_governor_dbs+0x529/0x6f0
[ 60.277709] [<ffffffff814b76a7>] cs_cpufreq_governor_dbs+0x17/0x20
[ 60.277719] [<ffffffff814b5df8>] __cpufreq_governor+0x48/0x100
[ 60.277728] [<ffffffff814b6b80>] __cpufreq_remove_dev.isra.14+0x80/0x3c0
[ 60.277737] [<ffffffff815adc0d>] cpufreq_cpu_callback+0x38/0x4c
[ 60.277747] [<ffffffff81071a4d>] notifier_call_chain+0x5d/0x110
[ 60.277759] [<ffffffff81071b0e>] __raw_notifier_call_chain+0xe/0x10
[ 60.277768] [<ffffffff815a0a68>] _cpu_down+0x88/0x330
[ 60.277779] [<ffffffff815a0d46>] cpu_down+0x36/0x50
[ 60.277788] [<ffffffff815a2748>] store_online+0x98/0xd0
[ 60.277796] [<ffffffff81452a28>] dev_attr_store+0x18/0x30
[ 60.277806] [<ffffffff811d9edb>] sysfs_write_file+0xdb/0x150
[ 60.277818] [<ffffffff8116806d>] vfs_write+0xbd/0x1f0
[ 60.277826] [<ffffffff811686fc>] SyS_write+0x4c/0xa0
[ 60.277834] [<ffffffff815bbbbe>] tracesys+0xd0/0xd5
[ 60.277842] other info that might help us debug this:
[ 60.277848] Chain exists of:
(&(&j_cdbs->work)->work) --> &j_cdbs->timer_mutex --> cpu_hotplug.lock
[ 60.277864] Possible unsafe locking scenario:
[ 60.277869] CPU0 CPU1
[ 60.277873] ---- ----
[ 60.277877] lock(cpu_hotplug.lock);
[ 60.277885] lock(&j_cdbs->timer_mutex);
[ 60.277892] lock(cpu_hotplug.lock);
[ 60.277900] lock((&(&j_cdbs->work)->work));
[ 60.277907] *** DEADLOCK ***
[ 60.277915] 6 locks held by bash/2225:
[ 60.277919] #0: (sb_writers#6){.+.+.+}, at: [<ffffffff81168173>] vfs_write+0x1c3/0x1f0
[ 60.277937] #1: (&buffer->mutex){+.+.+.}, at: [<ffffffff811d9e3c>] sysfs_write_file+0x3c/0x150
[ 60.277954] #2: (s_active#61){.+.+.+}, at: [<ffffffff811d9ec3>] sysfs_write_file+0xc3/0x150
[ 60.277972] #3: (x86_cpu_hotplug_driver_mutex){+.+...}, at: [<ffffffff81024cf7>] cpu_hotplug_driver_lock+0x17/0x20
[ 60.277990] #4: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff815a0d32>] cpu_down+0x22/0x50
[ 60.278007] #5: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81042d8b>] cpu_hotplug_begin+0x2b/0x60
[ 60.278023] stack backtrace:
[ 60.278031] CPU: 3 PID: 2225 Comm: bash Not tainted 3.10.0-rc7-dbg-01385-g241fd04-dirty #1744
[ 60.278037] Hardware name: Acer Aspire 5741G /Aspire 5741G , BIOS V1.20 02/08/2011
[ 60.278042] ffffffff8204e110 ffff88014df6b9f8 ffffffff815b3d90 ffff88014df6ba38
[ 60.278055] ffffffff815b0a8d ffff880150ed3f60 ffff880150ed4770 3871c4002c8980b2
[ 60.278068] ffff880150ed4748 ffff880150ed4770 ffff880150ed3f60 ffff88014df6bb00
[ 60.278081] Call Trace:
[ 60.278091] [<ffffffff815b3d90>] dump_stack+0x19/0x1b
[ 60.278101] [<ffffffff815b0a8d>] print_circular_bug+0x2b6/0x2c5
[ 60.278111] [<ffffffff810ab826>] __lock_acquire+0x1766/0x1d30
[ 60.278123] [<ffffffff81067e08>] ? __kernel_text_address+0x58/0x80
[ 60.278134] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[ 60.278142] [<ffffffff810621b5>] ? flush_work+0x5/0x280
[ 60.278151] [<ffffffff810621ed>] flush_work+0x3d/0x280
[ 60.278159] [<ffffffff810621b5>] ? flush_work+0x5/0x280
[ 60.278169] [<ffffffff810a9b14>] ? mark_held_locks+0x94/0x140
[ 60.278178] [<ffffffff81062d77>] ? __cancel_work_timer+0x77/0x120
[ 60.278188] [<ffffffff810a9cbd>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[ 60.278196] [<ffffffff81062d8a>] __cancel_work_timer+0x8a/0x120
[ 60.278206] [<ffffffff81062e53>] cancel_delayed_work_sync+0x13/0x20
[ 60.278214] [<ffffffff814b89d9>] cpufreq_governor_dbs+0x529/0x6f0
[ 60.278225] [<ffffffff814b76a7>] cs_cpufreq_governor_dbs+0x17/0x20
[ 60.278234] [<ffffffff814b5df8>] __cpufreq_governor+0x48/0x100
[ 60.278244] [<ffffffff814b6b80>] __cpufreq_remove_dev.isra.14+0x80/0x3c0
[ 60.278255] [<ffffffff815adc0d>] cpufreq_cpu_callback+0x38/0x4c
[ 60.278265] [<ffffffff81071a4d>] notifier_call_chain+0x5d/0x110
[ 60.278275] [<ffffffff81071b0e>] __raw_notifier_call_chain+0xe/0x10
[ 60.278284] [<ffffffff815a0a68>] _cpu_down+0x88/0x330
[ 60.278292] [<ffffffff81024cf7>] ? cpu_hotplug_driver_lock+0x17/0x20
[ 60.278302] [<ffffffff815a0d46>] cpu_down+0x36/0x50
[ 60.278311] [<ffffffff815a2748>] store_online+0x98/0xd0
[ 60.278320] [<ffffffff81452a28>] dev_attr_store+0x18/0x30
[ 60.278329] [<ffffffff811d9edb>] sysfs_write_file+0xdb/0x150
[ 60.278337] [<ffffffff8116806d>] vfs_write+0xbd/0x1f0
[ 60.278347] [<ffffffff81185950>] ? fget_light+0x320/0x4b0
[ 60.278355] [<ffffffff811686fc>] SyS_write+0x4c/0xa0
[ 60.278364] [<ffffffff815bbbbe>] tracesys+0xd0/0xd5
[ 60.280582] smpboot: CPU 1 is now offline
The intention of that commit was to avoid warnings during CPU
hotplug, which indicated that offline CPUs were getting IPIs from the
cpufreq governor's work items. But the real root-cause of that
problem was commit a66b2e5 (cpufreq: Preserve sysfs files across
suspend/resume) because it totally skipped all the cpufreq callbacks
during CPU hotplug in the suspend/resume path, and hence it never
actually shut down the cpufreq governor's worker threads during CPU
offline in the suspend/resume path.
Reflecting back, the reason why we never suspected that commit as the
root-cause earlier, was that the original issue was reported with
just the halt command and nobody had brought in suspend/resume to the
equation.
The reason for _that_ in turn, as it turns out, is that earlier
halt/shutdown was being done by disabling non-boot CPUs while tasks
were frozen, just like suspend/resume.... but commit cf7df378a
(reboot: migrate shutdown/reboot to boot cpu) which came somewhere
along that very same time changed that logic: shutdown/halt no longer
takes CPUs offline. Thus, the test-cases for reproducing the bug
were vastly different and thus we went totally off the trail.
Overall, it was one hell of a confusion with so many commits
affecting each other and also affecting the symptoms of the problems
in subtle ways. Finally, now since the original problematic commit
(a66b2e5) has been completely reverted, revert this intermediate fix
too (2f7021a8), to fix the CPU hotplug deadlock. Phew!
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Tested-by: Peter Wu <lekensteyn@gmail.com>
Cc: 3.10+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
