Supposedly for historical reasons, cpuset depends on cgroup core for
locking. It depends on cgroup_mutex in cgroup callbacks and grabs
cgroup_mutex from other places where it wants to be synchronized.
This is majorly messy and highly prone to introducing circular locking
dependency especially because cgroup_mutex is supposed to be one of
the outermost locks.
As previous patches already plugged possible races which may happen by
decoupling from cgroup_mutex, replacing cgroup_mutex with cpuset
specific cpuset_mutex is mostly straight-forward. Introduce
cpuset_mutex, replace all occurrences of cgroup_mutex with it, and add
cpuset_mutex locking to places which inherited cgroup_mutex from
cgroup core.
The only complication is from cpuset wanting to initiate task
migration when a cpuset loses all cpus or memory nodes. Task
migration may go through full cgroup and all subsystem locking and
should be initiated without holding any cpuset specific lock; however,
a previous patch already made hotplug handled asynchronously and
moving the task migration part outside other locks is easy.
cpuset_propagate_hotplug_workfn() now invokes
remove_tasks_in_empty_cpuset() without holding any lock.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cpuset is scheduled to be decoupled from cgroup_lock which will make
hotplug handling race with task migration. cpus or mems will be
allowed to go offline between ->can_attach() and ->attach(). If
hotplug takes down all cpus or mems of a cpuset while attach is in
progress, ->attach() may end up putting tasks into an empty cpuset.
This patchset makes ->attach() schedule hotplug propagation if the
cpuset is empty after attaching is complete. This will move the tasks
to the nearest ancestor which can execute and the end result would be
as if hotplug handling happened after the tasks finished attaching.
cpuset_write_resmask() now also flushes cpuset_propagate_hotplug_wq to
wait for propagations scheduled directly by cpuset_attach().
This currently doesn't make any functional difference as everything is
protected by cgroup_mutex but enables decoupling the locking.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cpuset is scheduled to be decoupled from cgroup_lock which will make
configuration updates race with task migration. Any config update
will be allowed to happen between ->can_attach() and ->attach(). If
such config update removes either all cpus or mems, by the time
->attach() is called, the condition verified by ->can_attach(), that
the cpuset is capable of hosting the tasks, is no longer true.
This patch adds cpuset->attach_in_progress which is incremented from
->can_attach() and decremented when the attach operation finishes
either successfully or not. validate_change() treats cpusets w/
non-zero ->attach_in_progress like cpusets w/ tasks and refuses to
remove all cpus or mems from it.
This currently doesn't make any functional difference as everything is
protected by cgroup_mutex but enables decoupling the locking.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cpuset_hotplug_workfn() has been invoking cpuset_propagate_hotplug()
directly to propagate hotplug updates to !root cpusets; however, this
has the following problems.
* cpuset locking is scheduled to be decoupled from cgroup_mutex,
cgroup_mutex will be unexported, and cgroup_attach_task() will do
cgroup locking internally, so propagation can't synchronously move
tasks to a parent cgroup while walking the hierarchy.
* We can't use cgroup generic tree iterator because propagation to
each cpuset may sleep. With propagation done asynchronously, we can
lose the rather ugly cpuset specific iteration.
Convert cpuset_propagate_hotplug() to
cpuset_propagate_hotplug_workfn() and execute it from newly added
cpuset->hotplug_work. The work items are run on an ordered workqueue,
so the propagation order is preserved. cpuset_hotplug_workfn()
schedules all propagations while holding cgroup_mutex and waits for
completion without cgroup_mutex. Each in-flight propagation holds a
reference to the cpuset->css.
This patch doesn't cause any functional difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
In general, we want to make cgroup_mutex one of the outermost locks
and be able to use get_online_cpus() and friends from cgroup methods.
With cpuset hotplug made async, get_online_cpus() can now be nested
inside cgroup_mutex.
Currently, cpuset avoids nesting get_online_cpus() inside cgroup_mutex
by bouncing sched_domain rebuilding to a work item. As such nesting
is allowed now, remove the workqueue bouncing code and always rebuild
sched_domains synchronously. This also nests sched_domains_mutex
inside cgroup_mutex, which is intended and should be okay.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
CPU / memory hotplug path currently grabs cgroup_mutex from hotplug
event notifications. We want to separate cpuset locking from cgroup
core and make cgroup_mutex outer to hotplug synchronization so that,
among other things, mechanisms which depend on get_online_cpus() can
be used from cgroup callbacks. In general, we want to keep
cgroup_mutex the outermost lock to minimize locking interactions among
different controllers.
Convert cpuset_handle_hotplug() to cpuset_hotplug_workfn() and
schedule it from the hotplug notifications. As the function can
already handle multiple mixed events without any input, converting it
to a work function is mostly trivial; however, one complication is
that cpuset_update_active_cpus() needs to update sched domains
synchronously to reflect an offlined cpu to avoid confusing the
scheduler. This is worked around by falling back to the the default
single sched domain synchronously before scheduling the actual hotplug
work. This makes sched domain rebuilt twice per CPU hotplug event but
the operation isn't that heavy and a lot of the second operation would
be noop for systems w/ single sched domain, which is the common case.
This decouples cpuset hotplug handling from the notification callbacks
and there can be an arbitrary delay between the actual event and
updates to cpusets. Scheduler and mm can handle it fine but moving
tasks out of an empty cpuset may race against writes to the cpuset
restoring execution resources which can lead to confusing behavior.
Flush hotplug work item from cpuset_write_resmask() to avoid such
confusions.
v2: Synchronous sched domain rebuilding using the fallback sched
domain added. This fixes various issues caused by confused
scheduler putting tasks on a dead CPU, including the one reported
by Li Zefan.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Reorganize hotplug path to prepare for async hotplug handling.
* Both CPU and memory hotplug handlings are collected into a single
function - cpuset_handle_hotplug(). It doesn't take any argument
but compares the current setttings of top_cpuset against what's
actually available to determine what happened. This function
directly updates top_cpuset. If there are CPUs or memory nodes
which are taken down, cpuset_propagate_hotplug() in invoked on all
!root cpusets.
* cpuset_propagate_hotplug() is responsible for updating the specified
cpuset so that it doesn't include any resource which isn't available
to top_cpuset. If no CPU or memory is left after update, all tasks
are moved to the nearest ancestor with both resources.
* update_tasks_cpumask() and update_tasks_nodemask() are now always
called after cpus or mems masks are updated even if the cpuset
doesn't have any task. This is for brevity and not expected to have
any measureable effect.
* cpu_active_mask and N_HIGH_MEMORY are read exactly once per
cpuset_handle_hotplug() invocation, all cpusets share the same view
of what resources are available, and cpuset_handle_hotplug() can
handle multiple resources going up and down. These properties will
allow async operation.
The reorganization, while drastic, is equivalent and shouldn't cause
any behavior difference. This will enable making hotplug handling
async and remove get_online_cpus() -> cgroup_mutex nesting.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cpuset_can_attach() prepare global variables cpus_attach and
cpuset_attach_nodemask_{to|from} which are used by cpuset_attach().
There is no reason to prepare in cpuset_can_attach(). The same
information can be accessed from cpuset_attach().
Move the prepartion logic from cpuset_can_attach() to cpuset_attach()
and make the global variables static ones inside cpuset_attach().
With this change, there's no reason to keep
cpuset_attach_nodemask_{from|to} global. Move them inside
cpuset_attach(). Unfortunately, we need to keep cpus_attach global as
it can't be allocated from cpuset_attach().
v2: cpus_attach not converted to cpumask_t as per Li Zefan and Rusty
Russell.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Instead of iterating cgroup->children directly, introduce and use
cpuset_for_each_child() which wraps cgroup_for_each_child() and
performs online check. As it uses the generic iterator, it requires
RCU read locking too.
As cpuset is currently protected by cgroup_mutex, non-online cpusets
aren't visible to all the iterations and this patch currently doesn't
make any functional difference. This will be used to de-couple cpuset
locking from cgroup core.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Add CS_ONLINE which is set from css_online() and cleared from
css_offline(). This will enable using generic cgroup iterator while
allowing decoupling cpuset from cgroup internal locking.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Add cpuset_css_on/offline() and rearrange css init/exit such that,
* Allocation and clearing to the default values happen in css_alloc().
Allocation now uses kzalloc().
* Config inheritance and registration happen in css_online().
* css_offline() undoes what css_online() did.
* css_free() frees.
This doesn't introduce any visible behavior changes. This will help
cleaning up locking.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
The function isn't that hot, the overhead of missing the fast exit is
low, the test itself depends heavily on cgroup internals, and it's
gonna be a hindrance when trying to decouple cpuset locking from
cgroup core. Remove the fast exit path.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Implement cgroup_rightmost_descendant() which returns the right most
descendant of the specified cgroup. This can be used to skip the
cgroup's subtree while iterating with
cgroup_for_each_descendant_pre().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Li Zefan <lizefan@huawei.com>
5edee61ede ("cgroup: cgroup_subsys->fork() should be called after the
task is added to css_set") removed cgroup_fork_callbacks() but forgot
to remove its dummy version for !CONFIG_CGROUPS. Remove it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Pull LED fix from Bryan Wu.
* 'fixes-for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
leds: leds-gpio: set devm_gpio_request_one() flags param correctly
commit a99d76f leds: leds-gpio: use gpio_request_one
changed the leds-gpio driver to use gpio_request_one() instead
of gpio_request() + gpio_direction_output()
Unfortunately, it also made a semantic change that breaks the
leds-gpio driver.
The gpio_request_one() flags parameter was set to:
GPIOF_DIR_OUT | (led_dat->active_low ^ state)
Since GPIOF_DIR_OUT is 0, the final flags value will just be the
XOR'ed value of led_dat->active_low and state.
This value were used to distinguish between HIGH/LOW output initial
level and call gpio_direction_output() accordingly.
With this new semantic gpio_request_one() will take the flags value
of 1 as a configuration of input direction (GPIOF_DIR_IN) and will
call gpio_direction_input() instead of gpio_direction_output().
int gpio_request_one(unsigned gpio, unsigned long flags, const char *label)
{
..
if (flags & GPIOF_DIR_IN)
err = gpio_direction_input(gpio);
else
err = gpio_direction_output(gpio,
(flags & GPIOF_INIT_HIGH) ? 1 : 0);
..
}
The right semantic is to evaluate led_dat->active_low ^ state and
set the output initial level explicitly.
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reported-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
Pull watchdog fixes from Wim Van Sebroeck:
"This fixes some small errors in the new da9055 driver, eliminates a
compiler warning and adds DT support for the twl4030_wdt driver (so
that we can have multiple watchdogs with DT on the omap platforms)."
* git://www.linux-watchdog.org/linux-watchdog:
watchdog: twl4030_wdt: add DT support
watchdog: omap_wdt: eliminate unused variable and a compiler warning
watchdog: da9055: Don't update wdt_dev->timeout in da9055_wdt_set_timeout error path
watchdog: da9055: Fix invalid free of devm_ allocated data
PCI: Reduce Ricoh 0xe822 SD card reader base clock frequency to 50MHz
PCI: Remove spurious error for sriov_numvfs store and simplify flow
PCI: Add PCIe Link Capability link speed and width names
PCI/PM: Do not suspend port if any subordinate device needs PME polling
PCI: Work around Stratus ftServer broken PCIe hierarchy (fix DMI check)
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Merge tag '3.8-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"Some fixes for v3.8. They include a fix for the new SR-IOV sysfs
management support, an expanded quirk for Ricoh SD card readers, a
Stratus DMI quirk fix, and a PME polling fix."
* tag '3.8-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: Reduce Ricoh 0xe822 SD card reader base clock frequency to 50MHz
PCI/PM: Do not suspend port if any subordinate device needs PME polling
PCI: Add PCIe Link Capability link speed and width names
PCI: Work around Stratus ftServer broken PCIe hierarchy (fix DMI check)
PCI: Remove spurious error for sriov_numvfs store and simplify flow
Commit 56c176c9ca ("UAPI: strip the _UAPI prefix from header guards
during header installation") strips the _UAPI prefix from header guards,
but only if there's a single space between the cpp directive and the
label.
Make it more flexible and able to handle tabs and multiple white space
characters.
Signed-off-by: David Howells <dhowell@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Empty files can get deleted by the patch program, so remove empty Kbuild
files and their links from the parent Kbuilds.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
overwriting a full page in the eCryptfs page cache, skip reading in and
decrypting the corresponding lower page.
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Merge tag 'ecryptfs-3.8-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs
Pull ecryptfs fixes from Tyler Hicks:
"Two self-explanatory fixes and a third patch which improves
performance: when overwriting a full page in the eCryptfs page cache,
skip reading in and decrypting the corresponding lower page."
* tag 'ecryptfs-3.8-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
fs/ecryptfs/crypto.c: make ecryptfs_encode_for_filename() static
eCryptfs: fix to use list_for_each_entry_safe() when delete items
eCryptfs: Avoid unnecessary disk read and data decryption during writing
Pull Ceph fixes from Sage Weil:
"Two of Alex's patches deal with a race when reseting server
connections for open RBD images, one demotes some non-fatal BUGs to
WARNs, and my patch fixes a protocol feature bit failure path."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: fix protocol feature mismatch failure path
libceph: WARN, don't BUG on unexpected connection states
libceph: always reset osds when kicking
libceph: move linger requests sooner in kick_requests()
Sasha was fuzzing with trinity and reported the following problem:
BUG: sleeping function called from invalid context at kernel/mutex.c:269
in_atomic(): 1, irqs_disabled(): 0, pid: 6361, name: trinity-main
2 locks held by trinity-main/6361:
#0: (&mm->mmap_sem){++++++}, at: [<ffffffff810aa314>] __do_page_fault+0x1e4/0x4f0
#1: (&(&mm->page_table_lock)->rlock){+.+...}, at: [<ffffffff8122f017>] handle_pte_fault+0x3f7/0x6a0
Pid: 6361, comm: trinity-main Tainted: G W
3.7.0-rc2-next-20121024-sasha-00001-gd95ef01-dirty #74
Call Trace:
__might_sleep+0x1c3/0x1e0
mutex_lock_nested+0x29/0x50
mpol_shared_policy_lookup+0x2e/0x90
shmem_get_policy+0x2e/0x30
get_vma_policy+0x5a/0xa0
mpol_misplaced+0x41/0x1d0
handle_pte_fault+0x465/0x6a0
This was triggered by a different version of automatic NUMA balancing
but in theory the current version is vunerable to the same problem.
do_numa_page
-> numa_migrate_prep
-> mpol_misplaced
-> get_vma_policy
-> shmem_get_policy
It's very unlikely this will happen as shared pages are not marked
pte_numa -- see the page_mapcount() check in change_pte_range() -- but
it is possible.
To address this, this patch restores sp->lock as originally implemented
by Kosaki Motohiro. In the path where get_vma_policy() is called, it
should not be calling sp_alloc() so it is not necessary to treat the PTL
specially.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
which could cause file system corruptions when performing file punch
operations.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 bug fixes from Ted Ts'o:
"Various bug fixes for ext4. Perhaps the most serious bug fixed is one
which could cause file system corruptions when performing file punch
operations."
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: avoid hang when mounting non-journal filesystems with orphan list
ext4: lock i_mutex when truncating orphan inodes
ext4: do not try to write superblock on ro remount w/o journal
ext4: include journal blocks in df overhead calcs
ext4: remove unaligned AIO warning printk
ext4: fix an incorrect comment about i_mutex
ext4: fix deadlock in journal_unmap_buffer()
ext4: split off ext4_journalled_invalidatepage()
jbd2: fix assertion failure in jbd2_journal_flush()
ext4: check dioread_nolock on remount
ext4: fix extent tree corruption caused by hole punch
Remove the unused argument (formerly no_context) from mpol_parse_str()
and from mpol_to_str().
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recently I suggested using "mount -o remount,mpol=local /tmp" in NUMA
mempolicy testing. Very nasty. Reading /proc/mounts, /proc/pid/mounts
or /proc/pid/mountinfo may then corrupt one bit of kernel memory, often
in a page table (causing "Bad swap" or "Bad page map" warning or "Bad
pagetable" oops), sometimes in a vm_area_struct or rbnode or somewhere
worse. "mpol=prefer" and "mpol=prefer:Node" are equally toxic.
Recent NUMA enhancements are not to blame: this dates back to 2.6.35,
when commit e17f74af35 "mempolicy: don't call mpol_set_nodemask() when
no_context" skipped mpol_parse_str()'s call to mpol_set_nodemask(),
which used to initialize v.preferred_node, or set MPOL_F_LOCAL in flags.
With slab poisoning, you can then rely on mpol_to_str() to set the bit
for node 0x6b6b, probably in the next page above the caller's stack.
mpol_parse_str() is only called from shmem_parse_options(): no_context
is always true, so call it unused for now, and remove !no_context code.
Set v.nodes or v.preferred_node or MPOL_F_LOCAL as mpol_to_str() might
expect. Then mpol_to_str() can ignore its no_context argument also,
the mpol being appropriately initialized whether contextualized or not.
Rename its no_context unused too, and let subsequent patch remove them
(that's not needed for stable backporting, which would involve rejects).
I don't understand why MPOL_LOCAL is described as a pseudo-policy:
it's a reasonable policy which suffers from a confusing implementation
in terms of MPOL_PREFERRED with MPOL_F_LOCAL. I believe this would be
much more robust if MPOL_LOCAL were recognized in switch statements
throughout, MPOL_F_LOCAL deleted, and MPOL_PREFERRED use the (possibly
empty) nodes mask like everyone else, instead of its preferred_node
variant (I presume an optimization from the days before MPOL_LOCAL).
But that would take me too long to get right and fully tested.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
EPOLL_CTL_MOD sets the interest mask before calling f_op->poll() to
ensure events are not missed. Since the modifications to the interest
mask are not protected by the same lock as ep_poll_callback, we need to
ensure the change is visible to other CPUs calling ep_poll_callback.
We also need to ensure f_op->poll() has an up-to-date view of past
events which occured before we modified the interest mask. So this
barrier also pairs with the barrier in wq_has_sleeper().
This should guarantee either ep_poll_callback or f_op->poll() (or both)
will notice the readiness of a recently-ready/modified item.
This issue was encountered by Andreas Voellmy and Junchang(Jason) Wang in:
http://thread.gmane.org/gmane.linux.kernel/1408782/
Signed-off-by: Eric Wong <normalperson@yhbt.net>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Voellmy <andreas.voellmy@yale.edu>
Tested-by: "Junchang(Jason) Wang" <junchang.wang@yale.edu>
Cc: netdev@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add DT support for twl4030_wdt. This is needed to get twl4030_wdt to
probe when booting with DT.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
We forgot to delete this in the commit 4f4753d9 (watchdog: omap_wdt:
convert to devm_ functions), and as a result the following compilation
warning was introduced:
drivers/watchdog/omap_wdt.c: In function 'omap_wdt_remove':
drivers/watchdog/omap_wdt.c:299:19: warning: unused variable 'res' [-Wunused-variable]
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Otherwise, WDIOC_GETTIMEOUT returns wrong value if set_timeout fails.
This patch also removes unnecessary ret variable in da9055_wdt_ping function.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
It is not required to free devm_ allocated data. Since kref_put
needs a valid release function, da9055_wdt_release_resources()
is not deleted.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Pull DRM update from Dave Airlie:
"This is a bit larger due to me not bothering to do anything since
before Xmas, and other people working too hard after I had clearly
given up.
It's got the 3 main x86 driver fixes pulls, and a bunch of tegra
fixes, doesn't fix the Ironlake bug yet, but that does seem to be
getting closer.
- radeon: gpu reset fixes and userspace packet support
- i915: watermark fixes, workarounds, i830/845 fix,
- nouveau: nvd9/kepler microcode fixes, accel is now enabled and
working, gk106 support
- tegra: misc fixes."
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (34 commits)
Revert "drm: tegra: protect DC register access with mutex"
drm: tegra: program only one window during modeset
drm: tegra: clean out old gem prototypes
drm: tegra: remove redundant tegra2_tmds_config entry
drm: tegra: protect DC register access with mutex
drm: tegra: don't leave clients host1x member uninitialized
drm: tegra: fix front_porch <-> back_porch mixup
drm/nve0/graph: fix fuc, and enable acceleration on all known chipsets
drm/nvc0/graph: fix fuc, and enable acceleration on GF119
drm/nouveau/bios: cache ramcfg strap on later chipsets
drm/nouveau/mxm: silence output if no bios data
drm/nouveau/bios: parse/display extra version component
drm/nouveau/bios: implement opcode 0xa9
drm/nouveau/bios: update gpio parsing apis to match current design
drm/nouveau: initial support for GK106
drm/radeon: add WAIT_UNTIL to evergreen VM safe reg list
drm/i915: disable shrinker lock stealing for create_mmap_offset
drm/i915: optionally disable shrinker lock stealing
drm/i915: fix flags in dma buf exporting
drm/radeon: add support for MEM_WRITE packet
...
From Tony Lindgren:
Here are few more patches to finish the omap changes for
multiplatform conversion that are not strictly fixes, but
were too complex to do with the dependencies during the
merge window. Those are to move of serial-omap.h to
platform_data, and the removal of remaining cpu_is_omap
macro usage outside mach-omap2.
Then there are several trivial fixes for typos and few
minimal omap2plus_defconfig updates.
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Merge tag 'omap-late-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull late ARM cleanups for omap from Olof Johansson:
"From Tony Lindgren:
Here are few more patches to finish the omap changes for multiplatform
conversion that are not strictly fixes, but were too complex to do
with the dependencies during the merge window. Those are to move of
serial-omap.h to platform_data, and the removal of remaining
cpu_is_omap macro usage outside mach-omap2.
Then there are several trivial fixes for typos and few minimal
omap2plus_defconfig updates."
* tag 'omap-late-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
arch/arm/mach-omap2/dpll3xxx.c: drop if around WARN_ON
OMAP2: Fix a typo - replace regist with register.
ARM/omap: use module_platform_driver macro
ARM: OMAP2+: PMU: Remove unused header
ARM: OMAP4: remove duplicated include from omap_hwmod_44xx_data.c
ARM: OMAP2+: omap2plus_defconfig: enable twl4030 SoC audio
ARM: OMAP2+: omap2plus_defconfig: Add tps65217 support
ARM: OMAP2+: enable devtmpfs and devtmpfs automount
ARM: OMAP2+: omap_twl: Change TWL4030_MODULE_PM_RECEIVER to TWL_MODULE_PM_RECEIVER
ARM: OMAP2+: Drop plat/cpu.h for omap2plus
ARM: OMAP: Split fb.c to remove last remaining cpu_is_omap usage
MAINTAINERS: Add an entry for omap related .dts files
It's been quiet over the holidays, but we have had a couple of trivial
fixes coming in for the newly introduced sunxi platform; one to add it
to the multiplatform defconfig for build coverage, and one fixup for
device tree strings.
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Merge tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"It's been quiet over the holidays, but we have had a couple of trivial
fixes coming in for the newly introduced sunxi platform; one to add it
to the multiplatform defconfig for build coverage, and one fixup for
device tree strings."
* tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
sunxi: Change the machine compatible string.
ARM: multi_v7_defconfig: Add ARCH_SUNXI
This reverts commit 83c0bcb694.
Lucas pointed out this was a mistake, and I missed the discussion,
so just revert it out to save a rebase.
Signed-off-by: Dave Airlie <airlied@redhat.com>
The intention is to program exactly WIN_A, not WIN_A and possibly
others.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
There is no gem.c anymore, those functions are implemented by the
drm_cma_helpers now.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The 720p and 1080p entries are completely redundant, as we are matching
the table entries against <=pclk.
Also generalize the comment, as we are using those table entries even
when driving other modes than the standard TV ones.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Window properties are programmed through a shared aperture and have to
happen atomically. Also we do the read-update-write dance on some of the
shared regs.
To make sure that different functions don't stumble over each other
protect the register access with a mutex.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
No real problem for now, as nothing is using this, but leaving it
unitialized is asking for trouble later on.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fixes wrong picture offset observed when using HDMI output with a
Technisat HD TV.
Signed-off-by: Lucas Stach <dev@lynxeye.de>
Acked-by: Mark Zhang <markz@nvidia.com>
Tested-by: Mark Zhang <markz@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Some fixes for 3.8:
- Watermark fixups from Chris Wilson (4 pieces).
- 2 snb workarounds, seem to be recently added to our internal DB.
- workaround for the infamous i830/i845 hang, seems now finally solid!
Based on Chris' fix for SNA, now also for UXA/mesa&old SNA.
- Some more fixlets for shrinker-pulls-the-rug issues (Chris&me).
- Fix dma-buf flags when exporting (you).
- Disable the VGA plane if it's enabled on lid open - similar fix in
spirit to the one I've sent you last weeek, BIOS' really like to mess
with the display when closing the lid (awesome debug work from Krzysztof
Mazur).
* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: disable shrinker lock stealing for create_mmap_offset
drm/i915: optionally disable shrinker lock stealing
drm/i915: fix flags in dma buf exporting
i915: ensure that VGA plane is disabled
drm/i915: Preallocate the drm_mm_node prior to manipulating the GTT drm_mm manager
drm: Export routines for inserting preallocated nodes into the mm manager
drm/i915: don't disable disconnected outputs
drm/i915: Implement workaround for broken CS tlb on i830/845
drm/i915: Implement WaSetupGtModeTdRowDispatch
drm/i915: Implement WaDisableHiZPlanesWhenMSAAEnabled
drm/i915: Prefer CRTC 'active' rather than 'enabled' during WM computations
drm/i915: Clear self-refresh watermarks when disabled
drm/i915: Double the cursor self-refresh latency on Valleyview
drm/i915: Fixup cursor latency used for IVB lp3 watermarks
Misc fixes for reset and new packets for userspace usage.
* 'drm-fixes-3.8' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon: add WAIT_UNTIL to evergreen VM safe reg list
drm/radeon: add support for MEM_WRITE packet
drm/radeon: restore modeset late in GPU reset path
drm/radeon: avoid deadlock in pm path when waiting for fence
drm/radeon: don't leave fence blocked process on failed GPU reset
Fixes the accel support for nvd9 + kepler chipsets, also fixes GK106 support.
* 'drm-nouveau-fixes-3.8' of git://anongit.freedesktop.org/git/nouveau/linux-2.6:
drm/nve0/graph: fix fuc, and enable acceleration on all known chipsets
drm/nvc0/graph: fix fuc, and enable acceleration on GF119
drm/nouveau/bios: cache ramcfg strap on later chipsets
drm/nouveau/mxm: silence output if no bios data
drm/nouveau/bios: parse/display extra version component
drm/nouveau/bios: implement opcode 0xa9
drm/nouveau/bios: update gpio parsing apis to match current design
drm/nouveau: initial support for GK106
An unintended consequence of commit 4ae0a48b5e ("mm: modify
pgdat_balanced() so that it also handles order-0") is that
wait_iff_congested() can now be called with NULL 'struct zone *'
producing kernel oops like this:
BUG: unable to handle kernel NULL pointer dereference
IP: [<ffffffff811542d9>] wait_iff_congested+0x59/0x140
This trivial patch fixes it.
Reported-by: Zhouping Liu <zliu@redhat.com>
Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Zlatko Calusic <zlatko.calusic@iskon.hr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'sunxi-fixes-for-3.8-rc2' of git://github.com/mripard/linux into fixes
From Maxime Ripard:
Fixes for the sunxi core to be merged in 3.8-rc2
* tag 'sunxi-fixes-for-3.8-rc2' of git://github.com/mripard/linux:
sunxi: Change the machine compatible string.
ARM: multi_v7_defconfig: Add ARCH_SUNXI
We should not set con->state to CLOSED here; that happens in
ceph_fault() in the caller, where it first asserts that the state
is not yet CLOSED. Avoids a BUG when the features don't match.
Since the fail_protocol() has become a trivial wrapper, replace
calls to it with direct calls to reset_connection().
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
A number of assertions in the ceph messenger are implemented with
BUG_ON(), killing the system if connection's state doesn't match
what's expected. At this point our state model is (evidently) not
well understood enough for these assertions to trigger a BUG().
Convert all BUG_ON(con->state...) calls to be WARN_ON(con->state...)
so we learn about these issues without killing the machine.
We now recognize that a connection fault can occur due to a socket
closure at any time, regardless of the state of the connection. So
there is really nothing we can assert about the state of the
connection at that point so eliminate that assertion.
Reported-by: Ugis <ugis22@gmail.com>
Tested-by: Ugis <ugis22@gmail.com>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Tejun Heo
Linus Torvalds
Javier Martinez Canillas
David Howells
Mel Gorman
Hugh Dickins
Eric Wong
Aaro Koskinen
Axel Lin
Dave Airlie
Lucas Stach
Zlatko Calusic
Olof Johansson
Sage Weil
Alex Elder