Greg Kroah-Hartman [Mon, 13 Jan 2014 21:55:05 +0000 (13:55 -0800)]
Revert "s390: use device_remove_file_self() instead of device_schedule_callback()"
This reverts commit
bdbb0a1376635d80e096f6433595a38984cf5408.
Tejun writes:
I'm sorry but can you please revert the whole series?
get_active() waiting while a node is deactivated has potential
to lead to deadlock and that deactivate/reactivate interface is
something fundamentally flawed and that cgroup will have to work
with the remove_self() like everybody else. IOW, I think the
first posting was correct.
Cc: Tejun Heo <tj@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Greg Kroah-Hartman [Mon, 13 Jan 2014 21:51:36 +0000 (13:51 -0800)]
Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()"
This reverts commit
d1ba277e79889085a2faec3b68b91ce89c63f888.
Tejun writes:
I'm sorry but can you please revert the whole series?
get_active() waiting while a node is deactivated has potential
to lead to deadlock and that deactivate/reactivate interface is
something fundamentally flawed and that cgroup will have to work
with the remove_self() like everybody else. IOW, I think the
first posting was correct.
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Greg Kroah-Hartman [Mon, 13 Jan 2014 21:50:31 +0000 (13:50 -0800)]
Revert "kernfs: remove unnecessary NULL check in __kernfs_remove()"
This reverts commit
88533f990c616cf50c2fe585ea03f75c806a293d.
Tejun writes:
I'm sorry but can you please revert the whole series?
get_active() waiting while a node is deactivated has potential
to lead to deadlock and that deactivate/reactivate interface is
something fundamentally flawed and that cgroup will have to work
with the remove_self() like everybody else. IOW, I think the
first posting was correct.
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Sat, 11 Jan 2014 23:23:23 +0000 (18:23 -0500)]
kernfs: remove unnecessary NULL check in __kernfs_remove()
895a068a524e ("kernfs: make kernfs_get_active() block if the node is
deactivated but not removed") added "struct kernfs_root *root =
kernfs_root(kn);" at the head of the function; however, the parameter
@kn is checked for later implying that the function may be called with
NULL. This means that we may end up invoking kernfs_root() with NULL
which will oops. None of the existing users invokes removal with NULL
@kn, so this bug doesn't actually trigger.
We can relocate kernfs_root() invocation after NULL check; however,
allowing NULL param tends to cause more confusion than actually
helping anything. As there's no existing user, let's remove the
spurious NULL check.
This bug was detected by smatch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Russell King [Fri, 10 Jan 2014 23:23:37 +0000 (23:23 +0000)]
drivers/base: provide an infrastructure for componentised subsystems
Subsystems such as ALSA, DRM and others require a single card-level
device structure to represent a subsystem. However, firmware tends to
describe the individual devices and the connections between them.
Therefore, we need a way to gather up the individual component devices
together, and indicate when we have all the component devices.
We do this in DT by providing a "superdevice" node which specifies
the components, eg:
imx-drm {
compatible = "fsl,drm";
crtcs = <&ipu1>;
connectors = <&hdmi>;
};
The superdevice is declared into the component support, along with the
subcomponents. The superdevice receives callbacks to locate the
subcomponents, and identify when all components are present. At this
point, we bind the superdevice, which causes the appropriate subsystem
to be initialised in the conventional way.
When any of the components or superdevice are removed from the system,
we unbind the superdevice, thereby taking the subsystem down.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:31 +0000 (08:57 -0500)]
sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()
All device_schedule_callback_owner() users are converted to use
device_remove_file_self(). Remove now unused
{sysfs|device}_schedule_callback_owner().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:30 +0000 (08:57 -0500)]
s390: use device_remove_file_self() instead of device_schedule_callback()
driver-core now supports synchrnous self-deletion of attributes and
the asynchrnous removal mechanism is scheduled for removal. Use it
instead of device_schedule_callback().
* Conversions in arch/s390/pci/pci_sysfs.c and
drivers/s390/block/dcssblk.c are straightforward.
* drivers/s390/cio/ccwgroup.c is a bit more tricky because
ccwgroup_notifier() was (ab)using device_schedule_callback() to
purely obtain a process context to kick off ungroup operation which
may block from a notifier callback.
Rename ccwgroup_ungroup_callback() to ccwgroup_ungroup() and make it
take ccwgroup_device * instead. The new function is now called
directly from ccwgroup_ungroup_store().
ccwgroup_notifier() chain is updated to explicitly bounce through
ccwgroup_device->ungroup_work. This also removes possible failure
from memory pressure.
Only compile-tested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:29 +0000 (08:57 -0500)]
scsi: use device_remove_file_self() instead of device_schedule_callback()
driver-core now supports synchrnous self-deletion of attributes and
the asynchrnous removal mechanism is scheduled for removal. Use it
instead of device_schedule_callback(). This makes "delete" behave
synchronously.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:28 +0000 (08:57 -0500)]
pci: use device_remove_file_self() instead of device_schedule_callback()
driver-core now supports synchrnous self-deletion of attributes and
the asynchrnous removal mechanism is scheduled for removal. Use it
instead of device_schedule_callback(). This makes "remove" behave
synchronously.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:27 +0000 (08:57 -0500)]
kernfs, sysfs, driver-core: implement kernfs_remove_self() and its wrappers
Sometimes it's necessary to implement a node which wants to delete
nodes including itself. This isn't straightforward because of kernfs
active reference. While a file operation is in progress, an active
reference is held and kernfs_remove() waits for all such references to
drain before completing. For a self-deleting node, this is a deadlock
as kernfs_remove() ends up waiting for an active reference that itself
is sitting on top of.
This currently is worked around in the sysfs layer using
sysfs_schedule_callback() which makes such removals asynchronous.
While it works, it's rather cumbersome and inherently breaks
synchronicity of the operation - the file operation which triggered
the operation may complete before the removal is finished (or even
started) and the removal may fail asynchronously. If a removal
operation is immmediately followed by another operation which expects
the specific name to be available (e.g. removal followed by rename
onto the same name), there's no way to make the latter operation
reliable.
The thing is there's no inherent reason for this to be asynchrnous.
All that's necessary to do this synchronous is a dedicated operation
which drops its own active ref and deactivates self. This patch
implements kernfs_remove_self() and its wrappers in sysfs and driver
core. kernfs_remove_self() is to be called from one of the file
operations, drops the active ref and deactivates using
__kernfs_deactivate_self(), removes the self node, and restores active
ref to the dead node using __kernfs_reactivate_self() so that the ref
is balanced afterwards. __kernfs_remove() is updated so that it takes
an early exit if the target node is already fully removed so that the
active ref restored by kernfs_remove_self() after removal doesn't
confuse the deactivation path.
This makes implementing self-deleting nodes very easy. The normal
removal path doesn't even need to be changed to use
kernfs_remove_self() for the self-deleting node. The method can
invoke kernfs_remove_self() on itself before proceeding the normal
removal path. kernfs_remove() invoked on the node by the normal
deletion path will simply be ignored.
This will replace sysfs_schedule_callback(). A subtle feature of
sysfs_schedule_callback() is that it collapses multiple invocations -
even if multiple removals are triggered, the removal callback is run
only once. An equivalent effect can be achieved by testing the return
value of kernfs_remove_self() - only the one which gets %true return
value should proceed with actual deletion. All other instances of
kernfs_remove_self() will wait till the enclosing kernfs operation
which invoked the winning instance of kernfs_remove_self() finishes
and then return %false. This trivially makes all users of
kernfs_remove_self() automatically show correct synchronous behavior
even when there are multiple concurrent operations - all "echo 1 >
delete" instances will finish only after the whole operation is
completed by one of the instances.
v2: For !CONFIG_SYSFS, dummy version kernfs_remove_self() was missing
and sysfs_remove_file_self() had incorrect return type. Fix it.
Reported by kbuild test bot.
v3: Updated to use __kernfs_{de|re}activate_self().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:26 +0000 (08:57 -0500)]
kernfs: implement kernfs_{de|re}activate[_self]()
This patch implements four functions to manipulate deactivation state
- deactivate, reactivate and the _self suffixed pair. A new fields
kernfs_node->deact_depth is added so that concurrent and nested
deactivations are handled properly. kernfs_node->hash is moved so
that it's paired with the new field so that it doesn't increase the
size of kernfs_node.
A kernfs user's lock would normally nest inside active ref but during
removal the user may want to perform kernfs_remove() while holding the
said lock, which would introduce a reverse locking dependency. This
function can be used to break such reverse dependency by allowing
deactivation step to performed separately outside user's critical
section.
This will also be used implement kernfs_remove_self().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:25 +0000 (08:57 -0500)]
kernfs: make kernfs_get_active() block if the node is deactivated but not removed
Currently, kernfs_get_active() fails if the target node is
deactivated. This is fine as a node always gets removed after
deactivation; however, we're gonna add reactivation so the assumption
won't hold. It'd be incorrect for kernfs_get_active() to fail for a
node which was deactivated only temporarily.
This patch makes kernfs_get_active() block if the node is deactivated
but not removed. If the node gets reactivated (not yet implemented),
it will be retried and succeed. If the node gets removed, it will be
woken up and fail.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:24 +0000 (08:57 -0500)]
kernfs: remove kernfs_addrm_cxt
kernfs_addrm_cxt and the accompanying kernfs_addrm_start/finish() were
added because there were operations which should be performed outside
kernfs_mutex after adding and removing kernfs_nodes. The necessary
operations were recorded in kernfs_addrm_cxt and performed by
kernfs_addrm_finish(); however, after the recent changes which
relocated deactivation and unmapping so that they're performed
directly during removal, the only operation kernfs_addrm_finish()
performs is kernfs_put(), which can be moved inside the removal path
too.
This patch moves the kernfs_put() of the base ref to __kernfs_remove()
and remove kernfs_addrm_cxt and kernfs_addrm_start/finish().
* kernfs_add_one() is updated to grab and release the parent's active
ref and kernfs_mutex itself. kernfs_get/put_active() and
kernfs_addrm_start/finish() invocations around it are removed from
all users.
* __kernfs_remove() puts an unlinked node directly instead of chaining
it to kernfs_addrm_cxt. Its callers are updated to grab and release
kernfs_mutex instead of calling kernfs_addrm_start/finish() around
it.
v2: Updated to fit the v2 restructuring of removal path.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:23 +0000 (08:57 -0500)]
kernfs: invoke kernfs_unmap_bin_file() directly from __kernfs_remove()
kernfs_unmap_bin_file() is supposed to unmap all memory mappings of
the target file before kernfs_remove() finishes; however, it currently
is being called from kernfs_addrm_finish() and has the same race
problem as the original implementation of deactivation when there are
multiple removers - only the remover which snatches the node to its
addrm_cxt->removed list is guaranteed to wait for its completion
before returning.
It can be fixed by moving kernfs_unmap_bin_file() invocation from
kernfs_addrm_finish() to __kernfs_remove(). The function may be
called multiple times but that shouldn't do any harm.
We end up dropping kernfs_mutex in the removal loop and the node may
be removed inbetween by someone else. kernfs_unlink_sibling() is
updated to test whether the node has already been removed and return
accordingly. __kernfs_remove() in turn performs post-unlinking
cleanup only if it actually unlinked the node.
KERNFS_HAS_MMAP test is moved out of the unmap function into
__kernfs_remove() so that we don't unlock kernfs_mutex unnecessarily.
While at it, drop the now meaningless "bin" qualifier from the
function name.
v2: Rewritten to fit the v2 restructuring of removal path. HAS_MMAP
test relocated.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:22 +0000 (08:57 -0500)]
kernfs: restructure removal path to fix possible premature return
The recursive nature of kernfs_remove() means that, even if
kernfs_remove() is not allowed to be called multiple times on the same
node, there may be race conditions between removal of parent and its
descendants. While we can claim that kernfs_remove() shouldn't be
called on one of the descendants while the removal of an ancestor is
in progress, such rule is unnecessarily restrictive and very difficult
to enforce. It's better to simply allow invoking kernfs_remove() as
the caller sees fit as long as the caller ensures that the node is
accessible.
The current behavior in such situations is broken. Whoever enters
removal path first takes the node off the hierarchy and then
deactivates. Following removers either return as soon as it notices
that it's not the first one or can't even find the target node as it
has already been removed from the hierarchy. In both cases, the
following removers may finish prematurely while the nodes which should
be removed and drained are still being processed by the first one.
This patch restructures so that multiple removers, whether through
recursion or direction invocation, always follow the following rules.
* When there are multiple concurrent removers, only one puts the base
ref.
* Regardless of which one puts the base ref, all removers are blocked
until the target node is fully deactivated and removed.
To achieve the above, removal path now first deactivates the subtree,
drains it and then unlinks one-by-one. __kernfs_deactivate() is
called directly from __kernfs_removal() and drops and regrabs
kernfs_mutex for each descendant to drain active refs. As this means
that multiple removers can enter __kernfs_deactivate() for the same
node, the function is updated so that it can handle multiple
deactivators of the same node - only one actually deactivates but all
wait till drain completion.
The restructured removal path guarantees that a removed node gets
unlinked only after the node is deactivated and drained. Combined
with proper multiple deactivator handling, this guarantees that any
invocation of kernfs_remove() returns only after the node itself and
all its descendants are deactivated, drained and removed.
v2: Draining separated into a separate loop (used to be in the same
loop as unlink) and done from __kernfs_deactivate(). This is to
allow exposing deactivation as a separate interface later.
Root node removal was broken in v1 patch. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:21 +0000 (08:57 -0500)]
kernfs: remove KERNFS_REMOVED
KERNFS_REMOVED is used to mark half-initialized and dying nodes so
that they don't show up in lookups and deny adding new nodes under or
renaming it; however, its role overlaps those of deactivation and
removal from rbtree.
It's necessary to deny addition of new children while removal is in
progress; however, this role considerably intersects with deactivation
- KERNFS_REMOVED prevents new children while deactivation prevents new
file operations. There's no reason to have them separate making
things more complex than necessary.
KERNFS_REMOVED is also used to decide whether a node is still visible
to vfs layer, which is rather redundant as equivalent determination
can be made by testing whether the node is on its parent's children
rbtree or not.
This patch removes KERNFS_REMOVED.
* Instead of KERNFS_REMOVED, each node now starts its life
deactivated. This means that we now use both atomic_add() and
atomic_sub() on KN_DEACTIVATED_BIAS, which is INT_MIN. The compiler
generates an overflow warnings when negating INT_MIN as the negation
can't be represented as a positive number. Nothing is actually
broken but let's bump BIAS by one to avoid the warnings for archs
which negates the subtrahend..
* KERNFS_REMOVED tests in add and rename paths are replaced with
kernfs_get/put_active() of the target nodes. Due to the way the add
path is structured now, active ref handling is done in the callers
of kernfs_add_one(). This will be consolidated up later.
* kernfs_remove_one() is updated to deactivate instead of setting
KERNFS_REMOVED. This removes deactivation from kernfs_deactivate(),
which is now renamed to kernfs_drain().
* kernfs_dop_revalidate() now tests RB_EMPTY_NODE(&kn->rb) instead of
KERNFS_REMOVED and KERNFS_REMOVED test in kernfs_dir_pos() is
dropped. A node which is removed from the children rbtree is not
included in the iteration in the first place. This means that a
node may be visible through vfs a bit longer - it's now also visible
after deactivation until the actual removal. This slightly enlarged
window difference doesn't make any difference to the userland.
* Sanity check on KERNFS_REMOVED in kernfs_put() is replaced with
checks on the active ref.
* Some comment style updates in the affected area.
v2: Reordered before removal path restructuring. kernfs_active()
dropped and kernfs_get/put_active() used instead. RB_EMPTY_NODE()
used in the lookup paths.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:20 +0000 (08:57 -0500)]
kernfs: remove KERNFS_ACTIVE_REF and add kernfs_lockdep()
There currently are two mechanisms gating active ref lockdep
annotations - KERNFS_LOCKDEP flag and KERNFS_ACTIVE_REF type mask.
The former disables lockdep annotations in kernfs_get/put_active()
while the latter disables all of kernfs_deactivate().
While KERNFS_ACTIVE_REF also behaves as an optimization to skip the
deactivation step for non-file nodes, the benefit is marginal and it
needlessly diverges code paths. Let's drop KERNFS_ACTIVE_REF and use
KERNFS_LOCKDEP in kernfs_deactivate() too.
While at it, add a test helper kernfs_lockdep() to test KERNFS_LOCKDEP
flag so that it's more convenient and the related code can be compiled
out when not enabled.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:19 +0000 (08:57 -0500)]
kernfs: replace kernfs_node->u.completion with kernfs_root->deactivate_waitq
kernfs_node->u.completion is used to notify deactivation completion
from kernfs_put_active() to kernfs_deactivate(). We now allow
multiple racing removals of the same node and the current removal
scheme is no longer correct - kernfs_remove() invocation may return
before the node is properly deactivated if it races against another
removal. The removal path will be restructured to address the issue.
To help such restructure which requires supporting multiple waiters,
this patch replaces kernfs_node->u.completion with
kernfs_root->deactivate_waitq. This makes deactivation event
notifications share a per-root waitqueue_head; however, the wait path
is quite cold and this will also allow shaving one pointer off
kernfs_node.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tejun Heo [Fri, 10 Jan 2014 13:57:18 +0000 (08:57 -0500)]
kernfs: fix get_active failure handling in kernfs_seq_*()
When kernfs_seq_start() fails to obtain an active reference, it
returns ERR_PTR(-ENODEV). kernfs_seq_stop() is then invoked with the
error pointer value; however, it still proceeds to invoke
kernfs_put_active() on the node leading to unbalanced put.
If kernfs_seq_stop() is called even after active ref failure, it
should skip invocation of @ops->seq_stop() and put_active.
Unfortunately, this is a bit complicated because active ref failure
isn't the only thing which may fail with ERR_PTR(-ENODEV).
@ops->seq_start/next() may also fail with the error value and
kernfs_seq_stop() doesn't have a way to tell apart those failures.
Work it around by factoring out the active part of kernfs_seq_stop()
into kernfs_seq_stop_active() and invoking it directly if
@ops->seq_start/next() fail with ERR_PTR(-ENODEV) and updating
kernfs_seq_stop() to skip kernfs_seq_stop_active() on
ERR_PTR(-ENODEV). This is a bit nasty but ensures that the active put
is skipped iff get_active failed in kernfs_seq_start().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ben Hutchings [Sat, 28 Dec 2013 15:53:59 +0000 (16:53 +0100)]
firmware_class: Fix the file size check
We expect to read firmware blobs with a single call to kernel_read(),
which returns int. Therefore the size must be within the range of
int, not long.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bart Van Assche [Sat, 4 Jan 2014 13:21:42 +0000 (14:21 +0100)]
driver-core: Fix use-after-free triggered by bus_unregister()
Avoid that bus_unregister() triggers a use-after-free with
CONFIG_DEBUG_KOBJECT_RELEASE=y. This patch avoids that the
following sequence triggers a kernel crash with memory poisoning
enabled:
* bus_register()
* driver_register()
* driver_unregister()
* bus_unregister()
The above sequence causes the bus private data to be freed from
inside the bus_unregister() call although it is not guaranteed in
that function that the reference count on the bus private data has
dropped to zero. As an example, with CONFIG_DEBUG_KOBJECT_RELEASE=y
the ${bus}/drivers kobject is still holding a reference on
bus->p->subsys.kobj via its parent pointer at the time the bus
private data is freed. Fix this by deferring freeing the bus private
data until the last kobject_put() call on bus->p->subsys.kobj.
The kernel oops triggered by the above sequence and with memory
poisoning enabled and that is fixed by this patch is as follows:
general protection fault: 0000 [#1] PREEMPT SMP
CPU: 3 PID: 2711 Comm: kworker/3:32 Tainted: G W O 3.13.0-rc4-debug+ #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: events kobject_delayed_cleanup
task:
ffff880037f866d0 ti:
ffff88003b638000 task.ti:
ffff88003b638000
Call Trace:
[<
ffffffff81263105>] ? kobject_get_path+0x25/0x100
[<
ffffffff81264354>] kobject_uevent_env+0x134/0x600
[<
ffffffff8126482b>] kobject_uevent+0xb/0x10
[<
ffffffff81262fa2>] kobject_delayed_cleanup+0xc2/0x1b0
[<
ffffffff8106c047>] process_one_work+0x217/0x700
[<
ffffffff8106bfdb>] ? process_one_work+0x1ab/0x700
[<
ffffffff8106c64b>] worker_thread+0x11b/0x3a0
[<
ffffffff8106c530>] ? process_one_work+0x700/0x700
[<
ffffffff81074b70>] kthread+0xf0/0x110
[<
ffffffff81074a80>] ? insert_kthread_work+0x80/0x80
[<
ffffffff815673bc>] ret_from_fork+0x7c/0xb0
[<
ffffffff81074a80>] ? insert_kthread_work+0x80/0x80
Code: 89 f8 48 89 e5 f6 82 c0 27 63 81 20 74 15 0f 1f 44 00 00 48 83 c0 01 0f b6 10 f6 82 c0 27 63 81 20 75 f0 5d c3 66 0f 1f 44 00 00 <80> 3f 00 55 48 89 e5 74 15 48 89 f8 0f 1f 40 00 48 83 c0 01 80
RIP [<
ffffffff81267ed0>] strlen+0x0/0x30
RSP <
ffff88003b639c70>
---[ end trace
210f883ef80376aa ]---
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bart Van Assche [Sat, 4 Jan 2014 13:20:36 +0000 (14:20 +0100)]
firmware loader: Add sparse annotation
Avoid that sparse reports the following warning on __fw_free_buf():
drivers/base/firmware_class.c:230:9: warning: context imbalance in '__fw_free_buf' - unexpected unlock
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bart Van Assche [Sat, 4 Jan 2014 13:20:04 +0000 (14:20 +0100)]
kobject: Fix source code comment spelling
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Greg Kroah-Hartman [Sun, 5 Jan 2014 03:56:40 +0000 (19:56 -0800)]
Revert "kobject: introduce kobj_completion"
This reverts commit
eee031649707db3c9920d9498f8d03819b74fc23.
Jeff writes:
I have no objections to reverting it. There were concerns from
Al Viro that it'd be tough to get right by callers and I had
assumed it got dropped after that. I had planned on using it in
my btrfs sysfs exports patchset but came up with a better way.
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Greg Kroah-Hartman [Tue, 24 Dec 2013 17:43:21 +0000 (09:43 -0800)]
Merge 3.13-rc5 into staging-next
We want these fixes here to handle some merge issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linus Torvalds [Sun, 22 Dec 2013 21:08:32 +0000 (13:08 -0800)]
Linux 3.13-rc5
Linus Torvalds [Sun, 22 Dec 2013 19:13:02 +0000 (11:13 -0800)]
Merge tag 'fixes-for-linus' of git://git./linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"Much smaller batch of fixes this week.
Biggest one is a revert of an OMAP display change that removed some
non-DT pinmux code that was still needed for 3.13 to get DSI displays
to work.
There's also a fix that resolves some misdescribed GPIO controller
resources on shmobile. The rest are mostly smaller fixes, a couple of
MAINTAINERS updates, etc"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
Revert "ARM: OMAP2+: Remove legacy mux code for display.c"
MAINTAINERS: Add keystone clock drivers
MAINTAINERS: Add keystone git tree information
ARM: s3c64xx: dt: Fix boot failure due to double clock initialization
ARM: shmobile: r8a7790: Fix GPIO resources in DTS
irqchip: renesas-intc-irqpin: Fix register bitfield shift calculation
ARM: shmobile: lager: phy fixup needs CONFIG_PHYLIB
Linus Torvalds [Sun, 22 Dec 2013 19:11:57 +0000 (11:11 -0800)]
Merge tag 'firewire-fix' of git://git./linux/kernel/git/ieee1394/linux1394
Pull firewire fixlet from Stefan Richter:
"A one-liner to reenable WRITE SAME over SBP-2 like in v3.8...v3.12.
Buggy targets which could malfunction when being subjected to this
command are already sufficiently protected by a scsi_level check in sd
+ SCSI core"
* tag 'firewire-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: sbp2: bring back WRITE SAME support
Linus Torvalds [Sun, 22 Dec 2013 19:11:20 +0000 (11:11 -0800)]
Merge git://git./linux/kernel/git/nab/target-pending
Pull SCSI target fixes from Nicholas Bellinger:
"Mostly minor items this time around, the most notable being a FILEIO
backend change to enforce hw_max_sectors based upon the current
block_size to address a bug where large sized I/Os (> 1M) where being
rejected"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
qla2xxx: Fix scsi_host leak on qlt_lport_register callback failure
target: Remove extra percpu_ref_init
target/file: Update hw_max_sectors based on current block_size
iser-target: Move INIT_WORK setup into isert_create_device_ib_res
iscsi-target: Fix incorrect np->np_thread NULL assignment
qla2xxx: Fix schedule_delayed_work() for target timeout calculations
iser-target: fix error return code in isert_create_device_ib_res()
iscsi-target: Fix-up all zero data-length CDBs with R/W_BIT set
target: Remove write-only stats fields and lock from struct se_node_acl
iscsi-target: return -EINVAL on oversized configfs parameter
Linus Torvalds [Sun, 22 Dec 2013 19:03:49 +0000 (11:03 -0800)]
Merge git://git.kvack.org/~bcrl/aio-next
Pull AIO leak fixes from Ben LaHaise:
"I've put these two patches plus Linus's change through a round of
tests, and it passes millions of iterations of the aio numa
migratepage test, as well as a number of repetitions of a few simple
read and write tests.
The first patch fixes the memory leak Kent introduced, while the
second patch makes aio_migratepage() much more paranoid and robust"
* git://git.kvack.org/~bcrl/aio-next:
aio/migratepages: make aio migrate pages sane
aio: fix kioctx leak introduced by "aio: Fix a trinity splat"
Linus Torvalds [Thu, 19 Dec 2013 20:11:12 +0000 (05:11 +0900)]
aio: clean up and fix aio_setup_ring page mapping
Since commit
36bc08cc01709 ("fs/aio: Add support to aio ring pages
migration") the aio ring setup code has used a special per-ring backing
inode for the page allocations, rather than just using random anonymous
pages.
However, rather than remembering the pages as it allocated them, it
would allocate the pages, insert them into the file mapping (dirty, so
that they couldn't be free'd), and then forget about them. And then to
look them up again, it would mmap the mapping, and then use
"get_user_pages()" to get back an array of the pages we just created.
Now, not only is that incredibly inefficient, it also leaked all the
pages if the mmap failed (which could happen due to excessive number of
mappings, for example).
So clean it all up, making it much more straightforward. Also remove
some left-overs of the previous (broken) mm_populate() usage that was
removed in commit
d6c355c7dabc ("aio: fix race in ring buffer page
lookup introduced by page migration support") but left the pointless and
now misleading MAP_POPULATE flag around.
Tested-and-acked-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Benjamin LaHaise [Sat, 21 Dec 2013 22:56:08 +0000 (17:56 -0500)]
aio/migratepages: make aio migrate pages sane
The arbitrary restriction on page counts offered by the core
migrate_page_move_mapping() code results in rather suspicious looking
fiddling with page reference counts in the aio_migratepage() operation.
To fix this, make migrate_page_move_mapping() take an extra_count parameter
that allows aio to tell the code about its own reference count on the page
being migrated.
While cleaning up aio_migratepage(), make it validate that the old page
being passed in is actually what aio_migratepage() expects to prevent
misbehaviour in the case of races.
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Benjamin LaHaise [Sat, 21 Dec 2013 20:49:28 +0000 (15:49 -0500)]
aio: fix kioctx leak introduced by "aio: Fix a trinity splat"
e34ecee2ae791df674dfb466ce40692ca6218e43 reworked the percpu reference
counting to correct a bug trinity found. Unfortunately, the change lead
to kioctxes being leaked because there was no final reference count to
put. Add that reference count back in to fix things.
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: stable@vger.kernel.org
Linus Torvalds [Sat, 21 Dec 2013 00:52:45 +0000 (16:52 -0800)]
Don't set the INITRD_COMPRESS environment variable automatically
Commit
1bf49dd4be0b ("./Makefile: export initial ramdisk compression
config option") started setting the INITRD_COMPRESS environment variable
depending on which decompression models the kernel had available.
That is completely broken.
For example, we by default have CONFIG_RD_LZ4 enabled, and are able to
decompress such an initrd, but the user tools to *create* such an initrd
may not be availble. So trying to tell dracut to generate an
lz4-compressed image just because we can decode such an image is
completely inappropriate.
Cc: J P <ppandit@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 20 Dec 2013 23:48:45 +0000 (15:48 -0800)]
Merge tag 'xfs-for-linus-v3.13-rc5' of git://oss.sgi.com/xfs/xfs
Pull xfs bugfixes from Ben Myers:
"This contains fixes for some asserts
related to project quotas, a memory leak, a hang when disabling group or
project quotas before disabling user quotas, Dave's email address, several
fixes for the alignment of file allocation to stripe unit/width geometry, a
fix for an assertion with xfs_zero_remaining_bytes, and the behavior of
metadata writeback in the face of IO errors.
Details:
- fix memory leak in xfs_dir2_node_removename
- fix quota assertion in xfs_setattr_size
- fix quota assertions in xfs_qm_vop_create_dqattach
- fix for hang when disabling group and project quotas before
disabling user quotas
- fix Dave Chinner's email address in MAINTAINERS
- fix for file allocation alignment
- fix for assertion in xfs_buf_stale by removing xfsbdstrat
- fix for alignment with swalloc mount option
- fix for "retry forever" semantics on IO errors"
* tag 'xfs-for-linus-v3.13-rc5' of git://oss.sgi.com/xfs/xfs:
xfs: abort metadata writeback on permanent errors
xfs: swalloc doesn't align allocations properly
xfs: remove xfsbdstrat error
xfs: align initial file allocations correctly
MAINTAINERS: fix incorrect mail address of XFS maintainer
xfs: fix infinite loop by detaching the group/project hints from user dquot
xfs: fix assertion failure at xfs_setattr_nonsize
xfs: fix false assertion at xfs_qm_vop_create_dqattach
xfs: fix memory leak in xfs_dir2_node_removename
Olof Johansson [Fri, 20 Dec 2013 22:28:05 +0000 (14:28 -0800)]
mm: fix build of split ptlock code
Commit
597d795a2a78 ('mm: do not allocate page->ptl dynamically, if
spinlock_t fits to long') restructures some allocators that are compiled
even if USE_SPLIT_PTLOCKS arn't used. It results in compilation
failure:
mm/memory.c:4282:6: error: 'struct page' has no member named 'ptl'
mm/memory.c:4288:12: error: 'struct page' has no member named 'ptl'
Add in the missing ifdef.
Fixes: 597d795a2a78 ('mm: do not allocate page->ptl dynamically, if spinlock_t fits to long')
Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 20 Dec 2013 21:50:42 +0000 (13:50 -0800)]
Merge tag 'arc-fixes-for-3.13-rc5' of git://git./linux/kernel/git/vgupta/arc
Pull ARC fix from Vineet Gupta:
"Fix busted syscall table due to unistd header inclusion issue"
* tag 'arc-fixes-for-3.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: Allow conditional multiple inclusion of uapi/asm/unistd.h
Linus Torvalds [Fri, 20 Dec 2013 21:50:08 +0000 (13:50 -0800)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux
Pull arm64 ptrace fix from Catalin Marinas.
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: ptrace: avoid using HW_BREAKPOINT_EMPTY for disabled events
Luck, Tony [Wed, 18 Dec 2013 23:17:10 +0000 (15:17 -0800)]
pstore: Don't allow high traffic options on fragile devices
Some pstore backing devices use on board flash as persistent
storage. These have limited numbers of write cycles so it
is a poor idea to use them from high frequency operations.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 20 Dec 2013 20:27:41 +0000 (12:27 -0800)]
Merge tag 'dmaengine-fixes-3.13-rc4' of git://git./linux/kernel/git/djbw/dmaengine
Pull dmaengine fixes from Dan Williams:
- deprecation of net_dma to be removed in 3.14
- crash regression fix in pl330 from the dmaengine_unmap rework
- crash regression fix for any channel running raid ops without
CONFIG_ASYNC_TX_DMA from dmaengine_unmap
- memory leak regression in mv_xor from dmaengine_unmap
- build warning regressions in mv_xor, fsldma, ppc4xx, txx9, and
at_hdmac from dmaengine_unmap
- sleep in atomic regression in dma_async_memcpy_pg_to_pg
- new fix in mv_xor for handling channel initialization failures
* tag 'dmaengine-fixes-3.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
net_dma: mark broken
dma: pl330: ensure DMA descriptors are zero-initialised
dmaengine: fix sleep in atomic
dmaengine: mv_xor: fix oops when channels fail to initialise
dma: mv_xor: Use dmaengine_unmap_data for the self-tests
dmaengine: fix enable for high order unmap pools
dma: fix build warnings in txx9
dmatest: fix build warning on mips
dma: fix fsldma build warnings
dma: fix build warnings in ppc4xx
dmaengine: at_hdmac: remove unused function
dma: mv_xor: remove mv_desc_get_dest_addr()
Linus Torvalds [Fri, 20 Dec 2013 20:26:54 +0000 (12:26 -0800)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"The PPC folks had a large amount of changes queued for 3.13, and now
they are fixing the bugs"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S HV: Don't drop low-order page address bits
powerpc: book3s: kvm: Don't abuse host r2 in exit path
powerpc/kvm/booke: Fix build break due to stack frame size warning
KVM: PPC: Book3S: PR: Enable interrupts earlier
KVM: PPC: Book3S: PR: Make svcpu -> vcpu store preempt savvy
KVM: PPC: Book3S: PR: Export kvmppc_copy_to|from_svcpu
KVM: PPC: Book3S: PR: Don't clobber our exit handler id
powerpc: kvm: fix rare but potential deadlock scene
KVM: PPC: Book3S HV: Take SRCU read lock around kvm_read_guest() call
KVM: PPC: Book3S HV: Make tbacct_lock irq-safe
KVM: PPC: Book3S HV: Refine barriers in guest entry/exit
KVM: PPC: Book3S HV: Fix physical address calculations
Kirill A. Shutemov [Fri, 20 Dec 2013 11:35:58 +0000 (13:35 +0200)]
mm: do not allocate page->ptl dynamically, if spinlock_t fits to long
In struct page we have enough space to fit long-size page->ptl there,
but we use dynamically-allocated page->ptl if size(spinlock_t) is larger
than sizeof(int).
It hurts 64-bit architectures with CONFIG_GENERIC_LOCKBREAK, where
sizeof(spinlock_t) == 8, but it easily fits into struct page.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rashika Kheria [Fri, 20 Dec 2013 15:08:23 +0000 (20:38 +0530)]
drivers: base: Add prototype declaration to the header file
Add prototype declaration of function memory_block_size_bytes() to
the header file include/linux/memory.h.
This eliminates the following warning in memory.c:
drivers/base/memory.c:87:1: warning: no previous prototype for ‘memory_block_size_bytes’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Johannes Weiner [Fri, 20 Dec 2013 14:54:12 +0000 (14:54 +0000)]
mm: page_alloc: revert NUMA aspect of fair allocation policy
Commit
81c0a2bb515f ("mm: page_alloc: fair zone allocator policy") meant
to bring aging fairness among zones in system, but it was overzealous
and badly regressed basic workloads on NUMA systems.
Due to the way kswapd and page allocator interacts, we still want to
make sure that all zones in any given node are used equally for all
allocations to maximize memory utilization and prevent thrashing on the
highest zone in the node.
While the same principle applies to NUMA nodes - memory utilization is
obviously improved by spreading allocations throughout all nodes -
remote references can be costly and so many workloads prefer locality
over memory utilization. The original change assumed that
zone_reclaim_mode would be a good enough predictor for that, but it
turned out to be as indicative as a coin flip.
Revert the NUMA aspect of the fairness until we can find a proper way to
make it configurable and agree on a sane default.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: <stable@kernel.org> # 3.12
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Fri, 20 Dec 2013 14:54:11 +0000 (14:54 +0000)]
Revert "mm: page_alloc: exclude unreclaimable allocations from zone fairness policy"
This reverts commit
73f038b863df. The NUMA behaviour of this patch is
less than ideal. An alternative approch is to interleave allocations
only within local zones which is implemented in the next patch.
Cc: stable@vger.kernel.org
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Fri, 20 Dec 2013 13:10:03 +0000 (15:10 +0200)]
mm: Fix NULL pointer dereference in madvise(MADV_WILLNEED) support
Sasha Levin found a NULL pointer dereference that is due to a missing
page table lock, which in turn is due to the pmd entry in question being
a transparent huge-table entry.
The code - introduced in commit
1998cc048901 ("mm: make
madvise(MADV_WILLNEED) support swap file prefetch") - correctly checks
for this situation using pmd_none_or_trans_huge_or_clear_bad(), but it
turns out that that function doesn't work correctly.
pmd_none_or_trans_huge_or_clear_bad() expected that pmd_bad() would
trigger if the transparent hugepage bit was set, but it doesn't do that
if pmd_numa() is also set. Note that the NUMA bit only gets set on real
NUMA machines, so people trying to reproduce this on most normal
development systems would never actually trigger this.
Fix it by removing the very subtle (and subtly incorrect) expectation,
and instead just checking pmd_trans_huge() explicitly.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
[ Additionally remove the now stale test for pmd_trans_huge() inside the
pmd_bad() case - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kevin Hilman [Fri, 20 Dec 2013 19:27:12 +0000 (11:27 -0800)]
Merge tag 'renesas-fixes-for-v3.13' of git://git./linux/kernel/git/horms/renesas into fixes
From Simon Horman:
Renesas ARM based SoC fixes for v3.13
* r8a7790 (R-Car H1) SoC
- Correct GPIO resources in DT.
This problem has been present since GPIOs were added to the r8a7790 SoC
by
f98e10c88aa95bf7 ("ARM: shmobile: r8a7790: Add GPIO controller
devices to device tree") in v3.12-rc1.
* irqchip renesas-intc-irqpin
- Correct register bitfield shift calculation
This bug has been present since the renesas-intc-irqpin driver was
introduced by
443580486e3b9657 ("irqchip: Renesas INTC External IRQ pin
driver") in v3.10-rc1
* Lager board
- Do not build the phy fixup unless CONFIG_PHYLIB is enabled
This problem was introduced by
48c8b96f21817aad
* tag 'renesas-fixes-for-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
ARM: shmobile: r8a7790: Fix GPIO resources in DTS
irqchip: renesas-intc-irqpin: Fix register bitfield shift calculation
ARM: shmobile: lager: phy fixup needs CONFIG_PHYLIB
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Paolo Bonzini [Fri, 20 Dec 2013 18:13:58 +0000 (19:13 +0100)]
Merge tag 'signed-for-3.13' of git://github.com/agraf/linux-2.6 into kvm-master
Patch queue for 3.13 - 2013-12-18
This fixes some grave issues we've only found after 3.13-rc1:
- Make the modularized HV/PR book3s kvm work well as modules
- Fix some race conditions
- Fix compilation with certain compilers (booke)
- Fix THP for book3s_hv
- Fix preemption for book3s_pr
Alexander Graf (4):
KVM: PPC: Book3S: PR: Don't clobber our exit handler id
KVM: PPC: Book3S: PR: Export kvmppc_copy_to|from_svcpu
KVM: PPC: Book3S: PR: Make svcpu -> vcpu store preempt savvy
KVM: PPC: Book3S: PR: Enable interrupts earlier
Aneesh Kumar K.V (1):
powerpc: book3s: kvm: Don't abuse host r2 in exit path
Paul Mackerras (5):
KVM: PPC: Book3S HV: Fix physical address calculations
KVM: PPC: Book3S HV: Refine barriers in guest entry/exit
KVM: PPC: Book3S HV: Make tbacct_lock irq-safe
KVM: PPC: Book3S HV: Take SRCU read lock around kvm_read_guest() call
KVM: PPC: Book3S HV: Don't drop low-order page address bits
Scott Wood (1):
powerpc/kvm/booke: Fix build break due to stack frame size warning
pingfan liu (1):
powerpc: kvm: fix rare but potential deadlock scene
Linus Torvalds [Fri, 20 Dec 2013 17:34:54 +0000 (09:34 -0800)]
Merge tag 'stable/for-linus-3.13-rc4-tag' of git://git./linux/kernel/git/xen/tip
Pull Xen bugfixes from Konrad Rzeszutek Wilk:
- Fix balloon driver for auto-translate guests (PVHVM, ARM) to not use
scratch pages.
- Fix block API header for ARM32 and ARM64 to have proper layout
- On ARM when mapping guests, stick on PTE_SPECIAL
- When using SWIOTLB under ARM, don't call swiotlb functions twice
- When unmapping guests memory and if we fail, don't return pages which
failed to be unmapped.
- Grant driver was using the wrong address on ARM.
* tag 'stable/for-linus-3.13-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/balloon: Seperate the auto-translate logic properly (v2)
xen/block: Correctly define structures in public headers on ARM32 and ARM64
arm: xen: foreign mapping PTEs are special.
xen/arm64: do not call the swiotlb functions twice
xen: privcmd: do not return pages which we have failed to unmap
XEN: Grant table address, xen_hvm_resume_frames, is a phys_addr not a pfn
Linus Torvalds [Fri, 20 Dec 2013 17:32:30 +0000 (09:32 -0800)]
Merge tag 'trace-fixes-v3.13-rc2' of git://git./linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt:
"This fixes a long standing bug in the ftrace profiler. The problem is
that the profiler only initializes the online CPUs, and not possible
CPUs. This causes issues if the user takes CPUs online or offline
while the profiler is running.
If we online a CPU after starting the profiler, we lose all the trace
information on the CPU going online.
If we offline a CPU after running a test and start a new test, it will
not clear the old data from that CPU.
This bug causes incorrect data to be reported to the user if they
online or offline CPUs during the profiling"
* tag 'trace-fixes-v3.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Initialize the ftrace profiler for each possible cpu
Kevin Hilman [Fri, 20 Dec 2013 16:30:50 +0000 (08:30 -0800)]
Merge tag 'omap-for-v3.13/display-fix' of git://git./linux/kernel/git/tmlind/linux-omap into fixes
I accidentally removed some mux code for omap4 that I thought was
dead code as omap4 has been booting with device tree only since
v3.10. Turns out I also removed some display related mux code,
so let's revert that except for the dead code parts.
* tag 'omap-for-v3.13/display-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: (439 commits)
Revert "ARM: OMAP2+: Remove legacy mux code for display.c"
+Linux 3.13-rc4
Kevin Hilman [Thu, 19 Dec 2013 23:12:23 +0000 (15:12 -0800)]
Merge tag 'keystone/maintainer-file' of git://git./linux/kernel/git/ssantosh/linux-keystone into fixes
From Santosh Shilimkar:
Couple of updates to MAINTAINERS file for Keystone
- Add git tree information
- Add clock drivers entry
* tag 'keystone/maintainer-file' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone:
MAINTAINERS: Add keystone clock drivers
MAINTAINERS: Add keystone git tree information
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Nicholas Bellinger [Tue, 17 Dec 2013 09:51:22 +0000 (01:51 -0800)]
qla2xxx: Fix scsi_host leak on qlt_lport_register callback failure
This patch fixes a possible scsi_host reference leak in qlt_lport_register(),
when a non zero return from the passed (*callback) does not call drop the
local reference via scsi_host_put() before returning.
This currently does not effect existing tcm_qla2xxx code as the passed callback
will never fail, but fix this up regardless for future code.
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Andy Grover [Tue, 26 Nov 2013 19:49:24 +0000 (11:49 -0800)]
target: Remove extra percpu_ref_init
lun->lun_ref is also initialized in core_tpg_post_addlun, so it doesn't
need to be done in core_tpg_setup_virtual_lun0.
(nab: Drop left-over percpu_ref_cancel_init in failure path)
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Linus Walleij [Thu, 12 Dec 2013 14:27:12 +0000 (15:27 +0100)]
Documentation: fix spelling in design-patterns
This fixes two spelling mistakes in the design pattern doc.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Axel Lin [Sat, 16 Nov 2013 08:15:23 +0000 (16:15 +0800)]
devtmpfs: Calling delete_path() only when necessary
The deleted variable is always 1 in current code.
Initialize deleted variable to be 0, so delete_path() will be called only when
necessary.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Will Deacon [Tue, 17 Dec 2013 17:09:08 +0000 (17:09 +0000)]
arm64: ptrace: avoid using HW_BREAKPOINT_EMPTY for disabled events
Commit
8f34a1da35ae ("arm64: ptrace: use HW_BREAKPOINT_EMPTY type for
disabled breakpoints") fixed an issue with GDB trying to zero breakpoint
control registers. The problem there is that the arch hw_breakpoint code
will attempt to create a (disabled), execute breakpoint of length 0.
This will fail validation and report unexpected failure to GDB. To avoid
this, we treated disabled breakpoints as HW_BREAKPOINT_EMPTY, but that
seems to have broken with recent kernels, causing watchpoints to be
treated as TYPE_INST in the core code and returning ENOSPC for any
further breakpoints.
This patch fixes the problem by prioritising the `enable' field of the
breakpoint: if it is cleared, we simply update the perf_event_attr to
indicate that the thing is disabled and don't bother changing either the
type or the length. This reinforces the behaviour that the breakpoint
control register is essentially read-only apart from the enable bit
when disabling a breakpoint.
Cc: <stable@vger.kernel.org>
Reported-by: Aaron Liu <liucy214@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Linus Torvalds [Thu, 19 Dec 2013 17:11:22 +0000 (09:11 -0800)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"An RT group-scheduling fix and the sched-domains topology setup fix
from Mel"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/rt: Fix rq's cpupri leak while enqueue/dequeue child RT entities
sched: Assign correct scheduling domain to 'sd_llc'
Linus Torvalds [Thu, 19 Dec 2013 17:10:46 +0000 (09:10 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"An ABI documentation fix, and a mixed-PMU perf-info-corruption fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Document the new transaction sample type
perf: Disable all pmus on unthrottling and rescheduling
Linus Torvalds [Thu, 19 Dec 2013 17:10:10 +0000 (09:10 -0800)]
Merge tag 'sound-3.13-rc5' of git://git./linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"We have a bit more changes than usual in ASoC here, as it was slipped
from the previous update. There are one minr ASoC PCM code fix and
ASoC dmaengine fix, in addition of a collection of small ASoC driver
fixes. The rest are a couple of HD-audio stable fixups, and a
long-standing fix for the paused stream handling.
So, all commits look not scary (and hopefully won't give you
disastrous holiday season)"
* tag 'sound-3.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Add Dell headset detection quirk for one more laptop model
ASoC: wm8904: fix DSP mode B configuration
ASoC: wm_adsp: Add small delay while polling DSP RAM start
ALSA: Add SNDRV_PCM_STATE_PAUSED case in wait_for_avail function
ASoC: kirkwood: Fix the CPU DAI rates
ASoC: wm5110: Correct HPOUT3 DAPM route typo
ALSA: hda - Add Dell headset detection quirk for three laptop models
ALSA: hda - Add enable_msi=0 workaround for four HP machines
ASoC: don't leak on error in snd_dmaengine_pcm_register
ASoC: fsl: imx-wm8962: Don't update bias_level in machine driver
ASoC: tegra: fix uninitialized variables in set_fmt
ASoC: wm8962: Enable SYSCLK provisonally before fetching generated DSPCLK_DIV
ASoC: sam9x5_wm8731: change to work in DSP A mode
ASoC: atmel_ssc_dai: add dai trigger ops
ASoC: soc-pcm: Use valid condition for snd_soc_dai_digital_mute() in hw_free()
Vineet Gupta [Thu, 19 Dec 2013 13:25:58 +0000 (18:55 +0530)]
ARC: Allow conditional multiple inclusion of uapi/asm/unistd.h
Commit
97bc386fc12d "ARC: Add guard macro to uapi/asm/unistd.h"
inhibited multiple inclusion of ARCH unistd.h. This however hosed the system
since Generic syscall table generator relies on it being included twice,
and in lack-of an empty table was emitted by C preprocessor.
Fix that by allowing one exception to rule for the special case (just
like Xtensa)
Suggested-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Takashi Iwai [Thu, 19 Dec 2013 11:22:11 +0000 (12:22 +0100)]
Merge tag 'asoc-v3.13-rc4' of git://git./linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v3.13
The fixes here are all driver specific ones, none of which particularly
stand out but all of which are useful to users of those drivers.
Mark Brown [Thu, 19 Dec 2013 10:25:27 +0000 (10:25 +0000)]
Merge remote-tracking branches 'asoc/fix/adsp', 'asoc/fix/arizona', 'asoc/fix/atmel', 'asoc/fix/fsl', 'asoc/fix/kirkwood', 'asoc/fix/tegra', 'asoc/fix/wm8904' and 'asoc/fix/wm8962' into asoc-linus
Mark Brown [Thu, 19 Dec 2013 10:25:27 +0000 (10:25 +0000)]
Merge remote-tracking branch 'asoc/fix/dma' into asoc-linus
Mark Brown [Thu, 19 Dec 2013 10:25:26 +0000 (10:25 +0000)]
Merge remote-tracking branch 'asoc/fix/core' into asoc-linus
Nicholas Bellinger [Thu, 12 Dec 2013 20:24:11 +0000 (12:24 -0800)]
target/file: Update hw_max_sectors based on current block_size
This patch allows FILEIO to update hw_max_sectors based on the current
max_bytes_per_io. This is required because vfs_[writev,readv]() can accept
a maximum of 2048 iovecs per call, so the enforced hw_max_sectors really
needs to be calculated based on block_size.
This addresses a >= v3.5 bug where block_size=512 was rejecting > 1M
sized I/O requests, because FD_MAX_SECTORS was hardcoded to 2048 for
the block_size=4096 case.
(v2: Use max_bytes_per_io instead of ->update_hw_max_sectors)
Reported-by: Henrik Goldman <hg@x-formation.com>
Cc: <stable@vger.kernel.org> #3.5+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Nicholas Bellinger [Thu, 12 Dec 2013 00:20:13 +0000 (16:20 -0800)]
iser-target: Move INIT_WORK setup into isert_create_device_ib_res
This patch moves INIT_WORK setup for cq_desc->cq_[rx,tx]_work into
isert_create_device_ib_res(), instead of being done each callback
invocation in isert_cq_[rx,tx]_callback().
This also fixes a 'INFO: trying to register non-static key' warning
when cancel_work_sync() is called before INIT_WORK has setup the
struct work_struct.
Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Cc: <stable@vger.kernel.org> #3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Nicholas Bellinger [Wed, 11 Dec 2013 23:45:32 +0000 (15:45 -0800)]
iscsi-target: Fix incorrect np->np_thread NULL assignment
When shutting down a target there is a race condition between
iscsit_del_np() and __iscsi_target_login_thread().
The latter sets the thread pointer to NULL, and the former
tries to issue kthread_stop() on that pointer without any
synchronization.
This patch moves the np->np_thread NULL assignment into
iscsit_del_np(), after kthread_stop() has completed. It also
removes the signal_pending() + np_state check, and only
exits when kthread_should_stop() is true.
Reported-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org> #3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Linus Torvalds [Thu, 19 Dec 2013 03:05:00 +0000 (19:05 -0800)]
Merge branch 'akpm' (incoming from Andrew)
Merge patches from Andrew Morton:
"23 fixes and a MAINTAINERS update"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (24 commits)
mm/hugetlb: check for pte NULL pointer in __page_check_address()
fix build with make 3.80
mm/mempolicy: fix !vma in new_vma_page()
MAINTAINERS: add Davidlohr as GPT maintainer
mm/memory-failure.c: recheck PageHuge() after hugetlb page migrate successfully
mm/compaction: respect ignore_skip_hint in update_pageblock_skip
mm/mempolicy: correct putback method for isolate pages if failed
mm: add missing dependency in Kconfig
sh: always link in helper functions extracted from libgcc
mm: page_alloc: exclude unreclaimable allocations from zone fairness policy
mm: numa: defer TLB flush for THP migration as long as possible
mm: numa: guarantee that tlb_flush_pending updates are visible before page table updates
mm: fix TLB flush race between migration, and change_protection_range
mm: numa: avoid unnecessary disruption of NUMA hinting during migration
mm: numa: clear numa hinting information on mprotect
sched: numa: skip inaccessible VMAs
mm: numa: avoid unnecessary work on the failure path
mm: numa: ensure anon_vma is locked to prevent parallel THP splits
mm: numa: do not clear PTE for pte_numa update
mm: numa: do not clear PMD during PTE update scan
...
Jianguo Wu [Thu, 19 Dec 2013 01:08:59 +0000 (17:08 -0800)]
mm/hugetlb: check for pte NULL pointer in __page_check_address()
In __page_check_address(), if address's pud is not present,
huge_pte_offset() will return NULL, we should check the return value.
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: qiuxishi <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Beulich [Thu, 19 Dec 2013 01:08:57 +0000 (17:08 -0800)]
fix build with make 3.80
According to Documentation/Changes, make 3.80 is still being supported
for building the kernel, hence make files must not make (unconditional)
use of features introduced only in newer versions.
Commit
1bf49dd4be0b ("./Makefile: export initial ramdisk compression
config option") however introduced "else ifeq" constructs which make
3.80 doesn't understand. Replace the logic there with more conventional
(in the kernel build infrastructure) list constructs (except that the
list here is intentionally limited to exactly one element).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: P J P <ppandit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wanpeng Li [Thu, 19 Dec 2013 01:08:56 +0000 (17:08 -0800)]
mm/mempolicy: fix !vma in new_vma_page()
BUG_ON(!vma) assumption is introduced by commit
0bf598d863e3 ("mbind:
add BUG_ON(!vma) in new_vma_page()"), however, even if
address = __vma_address(page, vma);
and
vma->start < address < vma->end
page_address_in_vma() may still return -EFAULT because of many other
conditions in it. As a result the while loop in new_vma_page() may end
with vma=NULL.
This patch revert the commit and also fix the potential dereference NULL
pointer reported by Dan.
http://marc.info/?l=linux-mm&m=
137689530323257&w=2
kernel BUG at mm/mempolicy.c:1204!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU: 3 PID: 7056 Comm: trinity-child3 Not tainted 3.13.0-rc3+ #2
task:
ffff8801ca5295d0 ti:
ffff88005ab20000 task.ti:
ffff88005ab20000
RIP: new_vma_page+0x70/0x90
RSP: 0000:
ffff88005ab21db0 EFLAGS:
00010246
RAX:
fffffffffffffff2 RBX:
0000000000000000 RCX:
0000000000000000
RDX:
0000000008040075 RSI:
ffff8801c3d74600 RDI:
ffffea00079a8b80
RBP:
ffff88005ab21dc8 R08:
0000000000000004 R09:
0000000000000000
R10:
0000000000000000 R11:
0000000000000000 R12:
fffffffffffffff2
R13:
ffffea00079a8b80 R14:
0000000000400000 R15:
0000000000400000
FS:
00007ff49c6f4740(0000) GS:
ffff880244e00000(0000) knlGS:
0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
00007ff49c68f994 CR3:
000000005a205000 CR4:
00000000001407e0
DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
Stack:
ffffea00079a8b80 ffffea00079a8bc0 ffffea00079a8ba0 ffff88005ab21e50
ffffffff811adc7a 0000000000000000 ffff8801ca5295d0 0000000464e224f8
0000000000000000 0000000000000002 0000000000000000 ffff88020ce75c00
Call Trace:
migrate_pages+0x12a/0x850
SYSC_mbind+0x513/0x6a0
SyS_mbind+0xe/0x10
ia32_do_call+0x13/0x13
Code: 85 c0 75 2f 4c 89 e1 48 89 da 31 f6 bf da 00 02 00 65 44 8b 04 25 08 f7 1c 00 e8 ec fd ff ff 5b 41 5c 41 5d 5d c3 0f 1f 44 00 00 <0f> 0b 66 0f 1f 44 00 00 4c 89 e6 48 89 df ba 01 00 00 00 e8 48
RIP [<
ffffffff8119f200>] new_vma_page+0x70/0x90
RSP <
ffff88005ab21db0>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Davidlohr Bueso [Thu, 19 Dec 2013 01:08:55 +0000 (17:08 -0800)]
MAINTAINERS: add Davidlohr as GPT maintainer
Add a new entry for the GPT standard. Any future changes will now be
routed through linux-efi.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Acked-by: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jianguo Wu [Thu, 19 Dec 2013 01:08:54 +0000 (17:08 -0800)]
mm/memory-failure.c: recheck PageHuge() after hugetlb page migrate successfully
After a successful hugetlb page migration by soft offline, the source
page will either be freed into hugepage_freelists or buddy(over-commit
page). If page is in buddy, page_hstate(page) will be NULL. It will
hit a NULL pointer dereference in dequeue_hwpoisoned_huge_page().
BUG: unable to handle kernel NULL pointer dereference at
0000000000000058
IP: [<
ffffffff81163761>] dequeue_hwpoisoned_huge_page+0x131/0x1d0
PGD
c23762067 PUD
c24be2067 PMD 0
Oops: 0000 [#1] SMP
So check PageHuge(page) after call migrate_pages() successfully.
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Tested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 19 Dec 2013 01:08:52 +0000 (17:08 -0800)]
mm/compaction: respect ignore_skip_hint in update_pageblock_skip
update_pageblock_skip() only fits to compaction which tries to isolate
by pageblock unit. If isolate_migratepages_range() is called by CMA, it
try to isolate regardless of pageblock unit and it don't reference
get_pageblock_skip() by ignore_skip_hint. We should also respect it on
update_pageblock_skip() to prevent from setting the wrong information.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: <stable@vger.kernel.org> [3.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 19 Dec 2013 01:08:51 +0000 (17:08 -0800)]
mm/mempolicy: correct putback method for isolate pages if failed
queue_pages_range() isolates hugetlbfs pages and putback_lru_pages()
can't handle these. We should change it to putback_movable_pages().
Naoya said that it is worth going into stable, because it can break
in-use hugepage list.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: <stable@vger.kernel.org> [3.12.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sima Baymani [Thu, 19 Dec 2013 01:08:49 +0000 (17:08 -0800)]
mm: add missing dependency in Kconfig
Eliminate the following (rand)config warning by adding missing PROC_FS
dependency:
warning: (HWPOISON_INJECT && MEM_SOFT_DIRTY) selects PROC_PAGE_MONITOR which has unmet direct dependencies (PROC_FS && MMU)
Signed-off-by: Sima Baymani <sima.baymani@gmail.com>
Suggested-by: David Rientjes <rientjes@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Geert Uytterhoeven [Thu, 19 Dec 2013 01:08:48 +0000 (17:08 -0800)]
sh: always link in helper functions extracted from libgcc
E.g. landisk_defconfig, which has CONFIG_NTFS_FS=m:
ERROR: "__ashrdi3" [fs/ntfs/ntfs.ko] undefined!
For "lib-y", if no symbols in a compilation unit are referenced by other
units, the compilation unit will not be included in vmlinux. This
breaks modules that do reference those symbols.
Use "obj-y" instead to fix this.
http://kisskb.ellerman.id.au/kisskb/buildresult/
8838077/
This doesn't fix all cases. There are others, e.g. udivsi3.
This is also not limited to sh, many architectures handle this in the
same way.
A simple solution is to unconditionally include all helper functions.
A more complex solution is to make the choice of "lib-y" or "obj-y" depend
on CONFIG_MODULES:
obj-$(CONFIG_MODULES) += ...
lib-y($CONFIG_MODULES) += ...
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Tested-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Reviewed-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Thu, 19 Dec 2013 01:08:47 +0000 (17:08 -0800)]
mm: page_alloc: exclude unreclaimable allocations from zone fairness policy
Dave Hansen noted a regression in a microbenchmark that loops around
open() and close() on an 8-node NUMA machine and bisected it down to
commit
81c0a2bb515f ("mm: page_alloc: fair zone allocator policy").
That change forces the slab allocations of the file descriptor to spread
out to all 8 nodes, causing remote references in the page allocator and
slab.
The round-robin policy is only there to provide fairness among memory
allocations that are reclaimed involuntarily based on pressure in each
zone. It does not make sense to apply it to unreclaimable kernel
allocations that are freed manually, in this case instantly after the
allocation, and incur the remote reference costs twice for no reason.
Only round-robin allocations that are usually freed through page reclaim
or slab shrinking.
Bisected by Dave Hansen.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:46 +0000 (17:08 -0800)]
mm: numa: defer TLB flush for THP migration as long as possible
THP migration can fail for a variety of reasons. Avoid flushing the TLB
to deal with THP migration races until the copy is ready to start.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:45 +0000 (17:08 -0800)]
mm: numa: guarantee that tlb_flush_pending updates are visible before page table updates
According to documentation on barriers, stores issued before a LOCK can
complete after the lock implying that it's possible tlb_flush_pending
can be visible after a page table update. As per revised documentation,
this patch adds a smp_mb__before_spinlock to guarantee the correct
ordering.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Thu, 19 Dec 2013 01:08:44 +0000 (17:08 -0800)]
mm: fix TLB flush race between migration, and change_protection_range
There are a few subtle races, between change_protection_range (used by
mprotect and change_prot_numa) on one side, and NUMA page migration and
compaction on the other side.
The basic race is that there is a time window between when the PTE gets
made non-present (PROT_NONE or NUMA), and the TLB is flushed.
During that time, a CPU may continue writing to the page.
This is fine most of the time, however compaction or the NUMA migration
code may come in, and migrate the page away.
When that happens, the CPU may continue writing, through the cached
translation, to what is no longer the current memory location of the
process.
This only affects x86, which has a somewhat optimistic pte_accessible.
All other architectures appear to be safe, and will either always flush,
or flush whenever there is a valid mapping, even with no permissions
(SPARC).
The basic race looks like this:
CPU A CPU B CPU C
load TLB entry
make entry PTE/PMD_NUMA
fault on entry
read/write old page
start migrating page
change PTE/PMD to new page
read/write old page [*]
flush TLB
reload TLB from new entry
read/write new page
lose data
[*] the old page may belong to a new user at this point!
The obvious fix is to flush remote TLB entries, by making sure that
pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may
still be accessible if there is a TLB flush pending for the mm.
This should fix both NUMA migration and compaction.
[mgorman@suse.de: fix build]
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:42 +0000 (17:08 -0800)]
mm: numa: avoid unnecessary disruption of NUMA hinting during migration
do_huge_pmd_numa_page() handles the case where there is parallel THP
migration. However, by the time it is checked the NUMA hinting
information has already been disrupted. This patch adds an earlier
check with some helpers.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:41 +0000 (17:08 -0800)]
mm: numa: clear numa hinting information on mprotect
On a protection change it is no longer clear if the page should be still
accessible. This patch clears the NUMA hinting fault bits on a
protection change.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:40 +0000 (17:08 -0800)]
sched: numa: skip inaccessible VMAs
Inaccessible VMA should not be trapping NUMA hint faults. Skip them.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:39 +0000 (17:08 -0800)]
mm: numa: avoid unnecessary work on the failure path
If a PMD changes during a THP migration then migration aborts but the
failure path is doing more work than is necessary.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:38 +0000 (17:08 -0800)]
mm: numa: ensure anon_vma is locked to prevent parallel THP splits
The anon_vma lock prevents parallel THP splits and any associated
complexity that arises when handling splits during THP migration. This
patch checks if the lock was successfully acquired and bails from THP
migration if it failed for any reason.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:37 +0000 (17:08 -0800)]
mm: numa: do not clear PTE for pte_numa update
The TLB must be flushed if the PTE is updated but change_pte_range is
clearing the PTE while marking PTEs pte_numa without necessarily
flushing the TLB if it reinserts the same entry. Without the flush,
it's conceivable that two processors have different TLBs for the same
virtual address and at the very least it would generate spurious faults.
This patch only unmaps the pages in change_pte_range for a full
protection change.
[riel@redhat.com: write pte_numa pte back to the page tables]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Chegu Vinod <chegu_vinod@hp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:36 +0000 (17:08 -0800)]
mm: numa: do not clear PMD during PTE update scan
If the PMD is flushed then a parallel fault in handle_mm_fault() will
enter the pmd_none and do_huge_pmd_anonymous_page() path where it'll
attempt to insert a huge zero page. This is wasteful so the patch
avoids clearing the PMD when setting pmd_numa.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:34 +0000 (17:08 -0800)]
mm: clear pmd_numa before invalidating
On x86, PMD entries are similar to _PAGE_PROTNONE protection and are
handled as NUMA hinting faults. The following two page table protection
bits are what defines them
_PAGE_NUMA:set _PAGE_PRESENT:clear
A PMD is considered present if any of the _PAGE_PRESENT, _PAGE_PROTNONE,
_PAGE_PSE or _PAGE_NUMA bits are set. If pmdp_invalidate encounters a
pmd_numa, it clears the present bit leaving _PAGE_NUMA which will be
considered not present by the CPU but present by pmd_present. The
existing caller of pmdp_invalidate should handle it but it's an
inconsistent state for a PMD. This patch keeps the state consistent
when calling pmdp_invalidate.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:33 +0000 (17:08 -0800)]
mm: numa: call MMU notifiers on THP migration
MMU notifiers must be called on THP page migration or secondary MMUs
will get very confused.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 19 Dec 2013 01:08:32 +0000 (17:08 -0800)]
mm: numa: serialise parallel get_user_page against THP migration
Base pages are unmapped and flushed from cache and TLB during normal
page migration and replaced with a migration entry that causes any
parallel NUMA hinting fault or gup to block until migration completes.
THP does not unmap pages due to a lack of support for migration entries
at a PMD level. This allows races with get_user_pages and
get_user_pages_fast which commit
3f926ab945b6 ("mm: Close races between
THP migration and PMD numa clearing") made worse by introducing a
pmd_clear_flush().
This patch forces get_user_page (fast and normal) on a pmd_numa page to
go through the slow get_user_page path where it will serialise against
THP migration and properly account for the NUMA hinting fault. On the
migration side the page table lock is taken for each PTE update.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vivek Goyal [Thu, 19 Dec 2013 01:08:31 +0000 (17:08 -0800)]
kexec: migrate to reboot cpu
Commit
1b3a5d02ee07 ("reboot: move arch/x86 reboot= handling to generic
kernel") moved reboot= handling to generic code. In the process it also
removed the code in native_machine_shutdown() which are moving reboot
process to reboot_cpu/cpu0.
I guess that thought must have been that all reboot paths are calling
migrate_to_reboot_cpu(), so we don't need this special handling. But
kexec reboot path (kernel_kexec()) is not calling
migrate_to_reboot_cpu() so above change broke kexec. Now reboot can
happen on non-boot cpu and when INIT is sent in second kerneo to bring
up BP, it brings down the machine.
So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid
this problem.
Bisected by WANG Chao.
Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Tested-by: Baoquan He <bhe@redhat.com>
Tested-by: WANG Chao <chaowang@redhat.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rafael J. Wysocki [Thu, 12 Dec 2013 05:11:02 +0000 (06:11 +0100)]
Driver core: Fix device_add_attrs() error code path
If the addition of dev_attr_online fails, device_add_attrs() should
remove device attribute groups as well as type and class attribute
groups before returning an error code. Make that happen.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linus Torvalds [Wed, 18 Dec 2013 22:35:00 +0000 (14:35 -0800)]
Merge tag 'usb-3.13-rc5' of git://git./linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are a few USB fixes for things that have people have reported
issues with recently"
* tag 'usb-3.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: ohci-at91: fix irq and iomem resource retrieval
usb: phy: fix driver dependencies
phy: kconfig: add depends on "USB_PHY" to OMAP_USB2 and TWL4030_USB
drivers: phy: tweaks to phy_create()
drivers: phy: Fix memory leak
xhci: Limit the spurious wakeup fix only to HP machines
usb: chipidea: fix nobody cared IRQ when booting with host role
usb: chipidea: host: Only disable the vbus regulator if it is not NULL
usb: serial: zte_ev: move support for ZTE AC2726 from zte_ev back to option
usb: cdc-wdm: manage_power should always set needs_remote_wakeup
usb: phy-tegra-usb.c: wrong pointer check for remap UTMI
usb: phy: twl6030-usb: signedness bug in twl6030_readb()
usb: dwc3: power off usb phy in error path
usb: dwc3: invoke phy_resume after phy_init
Linus Torvalds [Wed, 18 Dec 2013 22:34:27 +0000 (14:34 -0800)]
Merge tag 'tty-3.13-rc5' of git://git./linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are a few fixes for 3.13-rc5 that resolve a number of reported
tty and serial driver issues"
* tag 'tty-3.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: xuartps: Properly guard sysrq specific code
n_tty: Fix apparent order of echoed output
serial: 8250_dw: add new ACPI IDs
serial: 8250_dw: Fix LCR workaround regression
tty: Fix hang at ldsem_down_read()
Linus Torvalds [Wed, 18 Dec 2013 22:33:57 +0000 (14:33 -0800)]
Merge tag 'staging-3.13-rc5' of git://git./linux/kernel/git/gregkh/staging
Pull staging driver fixes from Greg KH:
"Here are a number of staging, and iio, fixes for 3.13-rc5 that resolve
some reported issues"
* tag 'staging-3.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
imx-drm: imx-drm-core: improve safety of imx_drm_add_crtc()
imx-drm: imx-drm-core: make imx_drm_crtc_register() safer
imx-drm: imx-drm-core: use defined constant for number of CRTCs.
imx-drm: imx-tve: don't call sleeping functions beneath enable_lock spinlock
imx-drm: ipu-v3: fix potential CRTC device registration race
imx-drm: imx-drm-core: fix DRM cleanup paths
imx-drm: imx-drm-core: fix error cleanup path for imx_drm_add_crtc()
staging: comedi: drivers: fix return value of comedi_load_firmware()
staging: comedi: 8255_pci: fix for newer PCI-DIO48H
iio:adc:ad7887 Fix channel reported endianness from cpu to big endian
iio:imu:adis16400 fix pressure channel scan type
staging:iio:mag:hmc5843 fix incorrect endianness of channel as a result of missuse of the IIO_ST macro.
iio: cm36651: Changed return value of read function
Linus Torvalds [Wed, 18 Dec 2013 22:33:23 +0000 (14:33 -0800)]
Merge tag 'driver-core-3.13-rc5' of git://git./linux/kernel/git/gregkh/driver-core
Pull driver core fix from Greg KH:
"Here's a single sysfs fix for 3.13-rc5 that resolves a lockdep issue
in sysfs that has been reported"
* tag 'driver-core-3.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
sysfs: give different locking key to regular and bin files
Linus Torvalds [Wed, 18 Dec 2013 22:09:08 +0000 (14:09 -0800)]
Merge branch 'keys-devel' of git://git./linux/kernel/git/dhowells/linux-fs
Pull crypto key patches from David Howells:
"There are four items:
- A patch to fix X.509 certificate gathering. The problem was that I
was coming up with a different path for signing_key.x509 in the
build directory if it didn't exist to if it did exist. This meant
that the X.509 cert container object file would be rebuilt on the
second rebuild in a build directory and the kernel would get
relinked.
- Unconditionally remove files generated by SYSTEM_TRUSTED_KEYRING=y
when doing make mrproper.
- Actually initialise the persistent-keyring semaphore for
init_user_ns. I have no idea why this works at all for users in
the base user namespace unless it's something to do with systemd
containerising the system.
- Documentation for module signing"
* 'keys-devel' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
Add Documentation/module-signing.txt file
KEYS: fix uninitialized persistent_keyring_register_sem
KEYS: Remove files generated when SYSTEM_TRUSTED_KEYRING=y
X.509: Fix certificate gathering
Dan Williams [Tue, 17 Dec 2013 18:09:32 +0000 (10:09 -0800)]
net_dma: mark broken
net_dma can cause data to be copied to a stale mapping if a
copy-on-write fault occurs during dma. The application sees missing
data.
The following trace is triggered by modifying the kernel to WARN if it
ever triggers copy-on-write on a page that is undergoing dma:
WARNING: CPU: 24 PID: 2529 at lib/dma-debug.c:485 debug_dma_assert_idle+0xd2/0x120()
ioatdma 0000:00:04.0: DMA-API: cpu touching an active dma mapped page [pfn=0x16bcd9]
Modules linked in: iTCO_wdt iTCO_vendor_support ioatdma lpc_ich pcspkr dca
CPU: 24 PID: 2529 Comm: linbug Tainted: G W 3.13.0-rc1+ #353
00000000000001e5 ffff88016f45f688 ffffffff81751041 ffff88017ab0ef70
ffff88016f45f6d8 ffff88016f45f6c8 ffffffff8104ed9c ffffffff810f3646
ffff8801768f4840 0000000000000282 ffff88016f6cca10 00007fa2bb699349
Call Trace:
[<
ffffffff81751041>] dump_stack+0x46/0x58
[<
ffffffff8104ed9c>] warn_slowpath_common+0x8c/0xc0
[<
ffffffff810f3646>] ? ftrace_pid_func+0x26/0x30
[<
ffffffff8104ee86>] warn_slowpath_fmt+0x46/0x50
[<
ffffffff8139c062>] debug_dma_assert_idle+0xd2/0x120
[<
ffffffff81154a40>] do_wp_page+0xd0/0x790
[<
ffffffff811582ac>] handle_mm_fault+0x51c/0xde0
[<
ffffffff813830b9>] ? copy_user_enhanced_fast_string+0x9/0x20
[<
ffffffff8175fc2c>] __do_page_fault+0x19c/0x530
[<
ffffffff8175c196>] ? _raw_spin_lock_bh+0x16/0x40
[<
ffffffff810f3539>] ? trace_clock_local+0x9/0x10
[<
ffffffff810fa1f4>] ? rb_reserve_next_event+0x64/0x310
[<
ffffffffa0014c00>] ? ioat2_dma_prep_memcpy_lock+0x60/0x130 [ioatdma]
[<
ffffffff8175ffce>] do_page_fault+0xe/0x10
[<
ffffffff8175c862>] page_fault+0x22/0x30
[<
ffffffff81643991>] ? __kfree_skb+0x51/0xd0
[<
ffffffff813830b9>] ? copy_user_enhanced_fast_string+0x9/0x20
[<
ffffffff81388ea2>] ? memcpy_toiovec+0x52/0xa0
[<
ffffffff8164770f>] skb_copy_datagram_iovec+0x5f/0x2a0
[<
ffffffff8169d0f4>] tcp_rcv_established+0x674/0x7f0
[<
ffffffff816a68c5>] tcp_v4_do_rcv+0x2e5/0x4a0
[..]
---[ end trace
e30e3b01191b7617 ]---
Mapped at:
[<
ffffffff8139c169>] debug_dma_map_page+0xb9/0x160
[<
ffffffff8142bf47>] dma_async_memcpy_pg_to_pg+0x127/0x210
[<
ffffffff8142cce9>] dma_memcpy_pg_to_iovec+0x119/0x1f0
[<
ffffffff81669d3c>] dma_skb_copy_datagram_iovec+0x11c/0x2b0
[<
ffffffff8169d1ca>] tcp_rcv_established+0x74a/0x7f0:
...the problem is that the receive path falls back to cpu-copy in
several locations and this trace is just one of the areas. A few
options were considered to fix this:
1/ sync all dma whenever a cpu copy branch is taken
2/ modify the page fault handler to hold off while dma is in-flight
Option 1 adds yet more cpu overhead to an "offload" that struggles to compete
with cpu-copy. Option 2 adds checks for behavior that is already documented as
broken when using get_user_pages(). At a minimum a debug mode is warranted to
catch and flag these violations of the dma-api vs get_user_pages().
Thanks to David for his reproducer.
Cc: <stable@vger.kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Reported-by: David Whipple <whipple@securedatainnovations.ch>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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