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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>
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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>
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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>
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Niels noted that we don't need the 'dentry = NULL' line.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Niels de Vos <ndevos@redhat.com>
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If we got the inode through fuse_iget() then the attributes are already
up-to-date.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
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Fuse does instantiation slightly differently from NFS/CIFS which use
d_materialise_unique().
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
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Add sanity checks before adding or updating an entry with data received
from readdirplus.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
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In case d_lookup() returns a dentry with d_inode == NULL, the dentry is not
returned with dput(). This results in triggering a BUG() in
shrink_dcache_for_umount_subtree():
BUG: Dentry ...{i=0,n=...} still in use (1) [unmount of fuse fuse]
[SzM: need to d_drop() as well]
Reported-by: Justin Clift <jclift@redhat.com>
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Brian Foster <bfoster@redhat.com>
Tested-by: Niels de Vos <ndevos@redhat.com>
CC: stable@vger.kernel.org
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In commit e3de42b68478a8c95dd27520e9adead2af9477a5
Author: Imre Deak <imre.deak@intel.com>
Date: Fri May 3 19:44:07 2013 +0200
drm/i915: force full modeset if the connector is in DPMS OFF mode
a new function was added that walked over the set of connectors to see
if any of the currently associated CRTC was switched off. This function
walked an array of connectors, rather than the array of pointers to
connectors contained in the drm_mode_set - i.e. it was dereferencing far
past the end of the first connector. This only becomes an issue if we
attempt to use a clone mode (i.e. more than one connector per CRTC) such
that set->num_connectors > 1.
Reported-by: Timo Aaltonen <tjaalton@ubuntu.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65927
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Egbert Eich <eich@suse.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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There seems to be no limit to the amount of gunk the firmware can
leave behind. Some platforms leave pch dplls on which are not in
active use at all. The example in the bug report is a Apple Macbook
Pro.
Note that this escape scrunity of the hw state checker until we've
tried to use this enabled, but unused pll since we did only check for
the inverse case of a in-used, but disabled pll.
v2: Add a WARN in the pll state checker which would have caught this
case.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66952
Reported-and-tested-by: shui yangwei <yangweix.shui@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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some MUSB incarnations, such as those governed by
omap2430.c and tusb6010.c, have three resources, not
two.
Fix the bug created by commit 09fc7d2 (usb: musb:
fix incorrect usage of resource pointer) where only
two of the three resources would be passed to musb_core.c
[ balbi@ti.com : add tusb6010.c to original patch ]
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
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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>
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This patch fixes regression in power consumtion of sandy bridge gpu, which
exists since v3.6 Sometimes after resuming from s2ram gpu starts thinking that
it's extremely busy. After that it never reaches rc6 state.
Bug exists since kernel v3.6:
commit b4ae3f22d238617ca11610b29fde16cf8c0bc6e0
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Thu Jun 14 11:04:48 2012 -0700
drm/i915: load boot context at driver init time
For some reason RC6 is already enabled at the beginning of resuming process.
Following initliaztion breaks some internal state and confuses RPS engine.
This patch disables RC6 at the beginnig of resume and initialization.
I've rearranged initialization sequence, because intel_disable_gt_powersave()
needs initialized force_wake_get/put and some locks from the dev_priv.
Note: The culprit in the initialization sequence seems to be the write
to MBCTL added in the above mentioned commit. The first version of
this patch just held a forcewake reference across the clock gating
init functions, which seems to have been enought to gather quite a few
positive test reports. But since that smelled a bit like ad-hoc
duct-tape v2 now just disables rps/rc6 across the entire hw setup.
References: https://bugs.freedesktop.org/show_bug.cgi?id=54089
References: https://bugzilla.kernel.org/show_bug.cgi?id=58971
References: https://patchwork.kernel.org/patch/2827634/ (patch v1)
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Add note about v1 vs. v2 of this patch and use standard
layout for the commit citation. Also add the tested-bys from v1 and a
cc: stable.]
Cc: stable@vger.kernel.org (Note: tiny conflict due to the addition of
the backlight lock in 3.11)
Tested-by: Alexander Kaltsas <alexkaltsas@gmail.com> (v1)
Tested-by: rocko <rockorequin@hotmail.com> (v1)
Tested-by: JohnMB <johnmbryant@sky.com> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Each subnet string needs to be separated with a semicolon. Fix this bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When we are posting pressure status, we may get interrupted and handle
the un-balloon operation. In this case just don't post the status as we
know the pressure status is stale.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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As we hot-add 128 MB chunks of memory, we wait to ensure that the memory
is onlined before attempting to hot-add the next chunk. If the udev rule for
memory hot-add is not executed within the allowed time, we would rollback the
state and abort further hot-add. Since the hot-add has succeeded and the only
failure is that the memory is not onlined within the allowed time, we should not
be rolling back the state. Fix this bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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unregistered
Whenever a device is unregistered in vmbus_device_unregister (drivers/hv/vmbus_drv.c), the device name in the log message may contain garbage as the memory has already been freed by the time pr_info is called. Log example:
[ 3149.170475] hv_vmbus: child device àõsèè0_5 unregistered
By logging the message just before calling device_unregister, the correct device name is printed:
[ 3145.034652] hv_vmbus: child device vmbus_0_5 unregistered
Also changing register & unregister messages to debug to avoid unnecessarily cluttering the kernel log.
Signed-off-by: Fernando M Soto <fsoto@bluecatnetworks.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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SG mode is not currently supported by netvsc, so remove this flag for now.
Otherwise, it will be unconditionally enabled by commit ec5f0615642
"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>
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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>
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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.
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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>
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__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>
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into for-3.11/drivers
Kent writes:
Hey Jens - I've been busy torture testing and chasing bugs, here's the
fruits of my labors. These are all fairly small fixes, some of them
quite important.
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Remove mach-shmobile mach/dma.h since it only
seems to be used on non-mach-shmobile platforms.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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This patch removes r8a7778_init_irq(), since no-one is using it.
And now, there is no reason to have r8a7778_init_irq_common().
r8a7778_init_irq_dt() includes it.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Update the STI timer frequency comment to 32.768 kHz to
fix 37 kHz typo.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Convert the EMEV2 SoC device setup code from using very
verbose resources and static platform devices to the
same style as more recent boards. This reduces the size
of the code.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Remove EMEV2 early console code from KZM9D and instead
rely on console setup during regular platform device
probe time. This makes the DT code and the KZM9D board
support behave the same.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Replace the SoC-specific callback init_machine() with
a NULL to use the default code. This cleans up the code
and reduces the number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Pass NULL to of_platform_populate instead of passing
an empty list. This cleans up the code and reduces the
number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Pass NULL to of_platform_populate instead of passing
an empty list. This cleans up the code and reduces the
number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Pass NULL to of_platform_populate instead of passing
an empty list. This cleans up the code and reduces the
number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Replace the SoC-specific callback init_machine() with
a NULL to use the default code. This cleans up the code
and reduces the number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Pass NULL to of_platform_populate instead of passing
an empty list. This cleans up the code and reduces the
number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Replace the SoC-specific callback init_machine() with
a NULL to use the default code. This cleans up the code
and reduces the number of lines.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Remove redundant irqchip_init() callback. The default case
of NULL will result in invoking irqchip_init() anyway.
Signed-off-by: Magnus Damm <damm@opensource.se>
[ horms+renesas@verge.net.au: Trimmed patch to remove portion
that updates the sh73a0 SoC and altered the subject to
use the same format as the patch that updates the sh73a0. ]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Commit ebafed7a ("ARM: irq: Call irqchip_init if no init_irq function is
specified") removed the need to explictly setup the init_irq field in
the machine description when using only irqchip_init. Remove that
declaration for shmobile as well.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Remove redundant irqchip_init() callback. The default case
of NULL will result in invoking irqchip_init() anyway.
Signed-off-by: Magnus Damm <damm@opensource.se>
[ horms+renesas@verge.net.au: Trimmed patch to remove portion
that updates the r8a7790 SoC and altered the subject to
use the same format as the patch that updates the r8a7790. ]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Commit ebafed7a ("ARM: irq: Call irqchip_init if no init_irq function is
specified") removed the need to explictly setup the init_irq field in
the machine description when using only irqchip_init. Remove that
declaration for shmobile as well.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Remove redundant irqchip_init() callback. The default case
of NULL will result in invoking irqchip_init() anyway.
Signed-off-by: Magnus Damm <damm@opensource.se>
[ horms+renesas@verge.net.au: Trimmed patch to remove portion
that updates the r8a73a4 SoC and altered the subject to
use the same format as the patch that updates the r8a73a4. ]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Commit ebafed7a ("ARM: irq: Call irqchip_init if no init_irq function is
specified") removed the need to explictly setup the init_irq field in
the machine description when using only irqchip_init. Remove that
declaration for shmobile as well.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Commit ebafed7a ("ARM: irq: Call irqchip_init if no init_irq function is
specified") removed the need to explictly setup the init_irq field in
the machine description when using only irqchip_init. Remove that
declaration for shmobile as well.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Use DEFINE_RES_MEM() and platform_device_register_simple()
to save a couple of lines of code.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[ remove const from resource pfc_resources to avoid section miss-match
reported by 4.4.5 ]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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These data will be kmemdup()'ed on
platform_device_add_resources() and platform_device_add_data()
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
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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>
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git://people.freedesktop.org/~danvet/drm-intel
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
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The hub driver was recently changed to use "global" suspend for system
suspend transitions on non-SuperSpeed buses. This means that we don't
suspend devices individually by setting the suspend feature on the
upstream hub port; instead devices all go into suspend automatically
when the root hub stops transmitting packets. The idea was to save
time and to avoid certain kinds of wakeup races.
Now it turns out that many hubs are buggy; they don't relay wakeup
requests from a downstream port to their upstream port if the
downstream port's suspend feature is not set (depending on the speed
of the downstream port, whether or not the hub is enabled for remote
wakeup, and possibly other factors).
We can't have hubs dropping wakeup requests. Therefore this patch
goes partway back to the old policy: It sets the suspend feature for a
port if the device attached to that port or any of its descendants is
enabled for wakeup. People will still be able to benefit from the
time savings if they don't care about wakeup and leave it disabled on
all their devices.
In order to accomplish this, the patch adds a new field to the usb_hub
structure: wakeup_enabled_descendants is a count of how many devices
below a suspended hub are enabled for remote wakeup. A corresponding
new subroutine determines the number of wakeup-enabled devices at or
below an arbitrary suspended USB device.
This should be applied to the 3.10 stable kernel.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The USB_MAXCHILDREN symbol is used in include/uapi/linux/usb/ch11.h, a
user-mode header, even though it is defined in include/linux/usb.h,
which is kernel-only. This causes compile-time errors when user
programs try to #include linux/usb/ch11.h.
This patch fixes the problem by moving the definition of USB_MAXCHILDREN
into ch11.h. It also gets rid of unneeded parentheses.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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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>
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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>
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