Minimize failures in this function by pre-allocating the buffer
for posting messages. The hypercall for posting the message can fail
for a number of reasons:
1. Transient resource related issues
2. Buffer alignment
3. Buffer cannot span a page boundry
We address issues 2 and 3 by preallocating a per-cpu page for the buffer.
Transient resource related failures are handled by retrying by the callers
of this function.
This patch is based on the investigation
done by Dexuan Cui <decui@microsoft.com>.
I would like to thank Sitsofe Wheeler <sitsofe@yahoo.com>
for reporting the issue and helping in debuggging.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com> Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Eliminate the call to BUG_ON() by waiting for the host to respond. We are
trying to reclaim the ownership of memory that was given to the host and so
we will have to wait until the host responds.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Eliminate calls to BUG_ON() by properly handling errors. In cases where
rollback is possible, we will return the appropriate error to have the
calling code decide how to rollback state. In the case where we are
transferring ownership of the guest physical pages to the host,
we will wait for the host to respond.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Posting messages to the host can fail because of transient resource
related failures. Correctly deal with these failures and increase the
number of attempts to post the message before giving up.
In this version of the patch, I have normalized the error code to
Linux error code.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Properly pack the data for file copy functionality. Patch based on
investigation done by Matej Muzila <mmuzila@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reported-by: <qge@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When returning from a debug exception taken from EL1, we unmask debug
exceptions after handling the exception. This is crucial for debug
exceptions taken from EL0, so that any kernel work on the ret_to_user
path can be debugged by kgdb.
However, when returning back to EL1 the only thing left to do is to
restore the original register state before the exception return. If
single-step has been enabled by the debug exception handler, we will
get stuck in an infinite debug exception loop, since we will take the
step exception as soon as we unmask debug exceptions.
This patch avoids unmasking debug exceptions on the debug exception
return path when the exception was taken from EL1.
Fixes: 2a2830703a23 (arm64: debug: avoid accessing mdscr_el1 on fault paths where possible) Reported-by: David Long <dave.long@linaro.org> Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If dma_async_device_register() returns error and probe should clean up
and return error, a NULL pointer exception happens because of
dereference of not allocated channel thread:
the partial xor result must be kept until the next
tx is generated.
Signed-off-by: Xuelin Shi <xuelin.shi@freescale.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Once calling scsi_host_put, be careful to not access qla_hw_data through
the Scsi_Host private data (ie, scsi_qla_host base_vha).
Fixes: fe1b806f4f71 ("qla2xxx: Refactor shutdown code so some functionality can be reused") Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Chad Dupuis <chad.dupuis@qlogic.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When allocating memory for new session original patch does
not assign vha to op->vha resulting into NULL pointer
access during qlt_create_sess_from_atio().
VCCR is used as a trigger to start voltage transitions, so
we need to mark it volatile in order to make sure it gets
written to hardware every time we set a new voltage.
Fixes regulator voltage being stuck at the first voltage
set after driver load.
[lst: reworded commit message] Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de> Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used
data can be improperly zeroed out using the mptfusion driver. This patch
disables write_same for this driver and the vmware subsystem_vendor which
ensures that manual zeroing out is used instead.
BugLink: http://bugs.launchpad.net/bugs/1371591 Reported-by: Bruce Lucas <bruce.lucas@mongodb.com> Tested-by: Chris J Arges <chris.j.arges@canonical.com> Signed-off-by: Chris J Arges <chris.j.arges@canonical.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dan Carpenter found a issue where be2iscsi would copy the ip
from userspace to the driver buffer before checking the len
of the data being copied:
http://marc.info/?l=linux-scsi&m=140982651504251&w=2
This patch just has us only copy what we the driver buffer
can support.
Tested-by: John Soni Jose <sony.john-n@emulex.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since we cannot make sure the 'val_count' will always be none zero
here, and then if it equals to zero, the kmemdup() will return
ZERO_SIZE_PTR, which equals to ((void *)16).
So this patch fix this with just doing the zero check before calling
kmemdup().
Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If LOG_DEVICE is defined and map->dev is NULL it will lead to NULL
pointer dereference. This patch fixes this issue by adding check for
dev->NULL in all such places in regmap.c
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If 'map->dev' is NULL and there will lead dev_name() to be NULL pointer
dereference. So before dev_name(), we need to have check of the map->dev
pionter.
We also should make sure that the 'name' pointer shouldn't be NULL for
debugfs_create_dir(). So here using one default "dummy" debugfs name when
the 'name' pointer and 'map->dev' are both NULL.
Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the Dell XPS 13 9333, it appears that sometimes the bus get confused
and corrupts the incoming data. It fills the input report with the
sentinel value "ff". Synaptics told us that such behavior does not comes
from the touchpad itself, so we filter out such reports here.
Unfortunately, we can not simply discard the incoming data because they
may contain useful information. Most of the time, the misbehavior is
quite near the end of the report, so we can still use the valid part of
it.
Some Wacom tablets (at least the ISDv4 found in the Lenovo X230) timeout
during probe while retrieving the input reports.
The only time this information is valuable is during the feature_mapping
stage, so we can ask for it there and discard the generic input reports
retrieval.
This gives a code path closer to the wacom.ko driver when it was in the
input subtree (not HID).
In my test on RK3288-pinky board, if spi is enabled, it will begin to
read data from slave regardless of whether the DMA is ready. So we
need prepare DMA before spi is enable.
Signed-off-by: Addy Ke <addy.ke@rock-chips.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of 8 bit mode and DMA usage we end up with every second byte written as
0. We have to respect bits_per_word settings what this patch actually does.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Quark x1000 advertises PGE via the standard CPUID method
PGE bits exist in Quark X1000's PTEs. In order to flush
an individual PTE it is necessary to reload CR3 irrespective
of the PTE.PGE bit.
See Quark Core_DevMan_001.pdf section 6.4.11
This bug was fixed in Galileo kernels, unfixed vanilla kernels are expected to
crash and burn on this platform.
CR4 isn't constant; at least the TSD and PCE bits can vary.
TBH, treating CR0 and CR3 as constant scares me a bit, too, but it looks
like it's correct.
This adds a branch and a read from cr4 to each vm entry. Because it is
extremely likely that consecutive entries into the same vcpu will have
the same host cr4 value, this fixes up the vmcs instead of restoring cr4
after the fact. A subsequent patch will add a kernel-wide cr4 shadow,
reducing the overhead in the common case to just two memory reads and a
branch.
Signed-off-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vcpu ioctls can hang the calling thread if issued while a vcpu is running.
However, invalid ioctls can happen when userspace tries to probe the kind
of file descriptors (e.g. isatty() calls ioctl(TCGETS)); in that case,
we know the ioctl is going to be rejected as invalid anyway and we can
fail before trying to take the vcpu mutex.
This patch does not change functionality, it just makes invalid ioctls
fail faster.
Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The next patch will give a meaning (a la seqcount) to the low bit of the
generation number. Ensure that it matches between kvm->memslots->generation
and kvm_current_mmio_generation().
Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vcpu exits and memslot mutations can run concurrently as long as the
vcpu does not aquire the slots mutex. Thus it is theoretically possible
for memslots to change underneath a vcpu that is handling an exit.
If we increment the memslot generation number again after
synchronize_srcu_expedited(), vcpus can safely cache memslot generation
without maintaining a single rcu_dereference through an entire vm exit.
And much of the x86/kvm code does not maintain a single rcu_dereference
of the current memslots during each exit.
We can prevent the following case:
vcpu (CPU 0) | thread (CPU 1)
--------------------------------------------+--------------------------
1 vm exit |
2 srcu_read_unlock(&kvm->srcu) |
3 decide to cache something based on |
old memslots |
4 | change memslots
| (increments generation)
5 | synchronize_srcu(&kvm->srcu);
6 retrieve generation # from new memslots |
7 tag cache with new memslot generation |
8 srcu_read_unlock(&kvm->srcu) |
... |
<action based on cache occurs even |
though the caching decision was based |
on the old memslots> |
... |
<action *continues* to occur until next |
memslot generation change, which may |
be never> |
|
By incrementing the generation after synchronizing with kvm->srcu readers,
we ensure that the generation retrieved in (6) will become invalid soon
after (8).
Keeping the existing increment is not strictly necessary, but we
do keep it and just move it for consistency from update_memslots to
install_new_memslots. It invalidates old cached MMIOs immediately,
instead of having to wait for the end of synchronize_srcu_expedited,
which makes the code more clearly correct in case CPU 1 is preempted
right after synchronize_srcu() returns.
To avoid halving the generation space in SPTEs, always presume that the
low bit of the generation is zero when reconstructing a generation number
out of an SPTE. This effectively disables MMIO caching in SPTEs during
the call to synchronize_srcu_expedited. Using the low bit this way is
somewhat like a seqcount---where the protected thing is a cache, and
instead of retrying we can simply punt if we observe the low bit to be 1.
Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The following events can lead to an incorrect KVM_EXIT_MMIO bubbling
up to userspace:
(1) Guest accesses gpa X without a memory slot. The gfn is cached in
struct kvm_vcpu_arch (mmio_gfn). On Intel EPT-enabled hosts, KVM sets
the SPTE write-execute-noread so that future accesses cause
EPT_MISCONFIGs.
(2) Host userspace creates a memory slot via KVM_SET_USER_MEMORY_REGION
covering the page just accessed.
(3) Guest attempts to read or write to gpa X again. On Intel, this
generates an EPT_MISCONFIG. The memory slot generation number that
was incremented in (2) would normally take care of this but we fast
path mmio faults through quickly_check_mmio_pf(), which only checks
the per-vcpu mmio cache. Since we hit the cache, KVM passes a
KVM_EXIT_MMIO up to userspace.
This patch fixes the issue by using the memslot generation number
to validate the mmio cache.
Signed-off-by: David Matlack <dmatlack@google.com>
[xiaoguangrong: adjust the code to make it simpler for stable-tree fix.] Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Tested-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds the PCI id for Intel Quark ILB.
It will be used for GPIO and Multifunction device driver.
Signed-off-by: Josef Ahmad <josef.ahmad@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Chang Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Switching only one commit root during a transaction is wrong because it
leads the fs into an inconsistent state. All commit roots should be
switched at once, at transaction commit time, otherwise backref walking
can often miss important references that were only accessible through
the old commit root. Plus, the root item for the snapshot's root wasn't
getting updated and preventing the next transaction commit to do it.
This made several users get into random corruption issues after creation
of readonly snapshots.
A regression test for xfstests will follow soon.
Cc: stable@vger.kernel.org # 3.17 Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We check whether transid is already committed via last_trans_committed and
then search through trans_list for pending transactions. If
last_trans_committed is updated by btrfs_commit_transaction after we check
it (there is no locking), we will fail to find the committed transaction
and return EINVAL to the caller. This has been observed occasionally by
ceph-osd (which uses this ioctl heavily).
Fix by rechecking whether the provided transid <= last_trans_committed
after the search fails, and if so return 0.
Signed-off-by: Sage Weil <sage@redhat.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previous commit: btrfs: Fix and enhance merge_extent_mapping() to insert
best fitted extent map
is using wrong condition to judgement whether the range is a subset of a
existing extent map.
This may cause bug in btrfs no-holes mode.
This patch will correct the judgment and fix the bug.
Marc Merlin sent me a broken fs image months ago where it would blow up in the
upper->checked BUG_ON() in build_backref_tree. This is because we had a
scenario like this
block a -- level 4 (not shared)
|
block b -- level 3 (reloc block, shared)
|
block c -- level 2 (not shared)
|
block d -- level 1 (shared)
|
block e -- level 0 (shared)
We go to build a backref tree for block e, we notice block d is shared and add
it to the list of blocks to lookup it's backrefs for. Now when we loop around
we will check edges for the block, so we will see we looked up block c last
time. So we lookup block d and then see that the block that points to it is
block c and we can just skip that edge since we've already been up this path.
The problem is because we clear need_check when we see block d (as it is shared)
we never add block b as needing to be checked. And because block c is in our
path already we bail out before we walk up to block b and add it to the backref
check list.
To fix this we need to reset need_check if we trip over a block that doesn't
need to be checked. This will make sure that any subsequent blocks in the path
as we're walking up afterwards are added to the list to be processed. With this
patch I can now mount Marc's fs image and it'll complete the balance without
panicing. Thanks,
Reported-by: Marc MERLIN <marc@merlins.org> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
test, because it means it couldn't build the backref tree properly. This is
annoying to users and frankly a recoverable error, nothing in this function is
actually fatal since it is just an in-memory building of the backrefs for a
given bytenr. So go through and change all the BUG_ON()'s to ASSERT()'s, and
fix the BUG_ON(!upper->checked) thing to just return an error.
This patch also fixes the error handling so it tears down the work we've done
properly. This code was horribly broken since we always just panic'ed instead
of actually erroring out, so it needed to be completely re-worked. With this
patch my broken image no longer panics when I mount it. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When doing log replay we may have to update inodes, which traditionally goes
through our delayed inode stuff. This will try to move space over from the
trans handle, but we don't reserve space in our trans handle on replay since we
don't know how much we will need, so instead we try to flush. But because we
have a trans handle open we won't flush anything, so if we are out of reserve
space we will simply return ENOSPC. Since we know that if an operation made it
into the log then we definitely had space before the box bought the farm then we
don't need to worry about doing this space reservation. Use the
fs_info->log_root_recovering flag to skip the delayed inode stuff and update the
item directly. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Trying to reproduce a log enospc bug I hit a panic in the async reclaim code
during log replay. This is because we use fs_info->fs_root as our root for
shrinking and such. Technically we can use whatever root we want, but let's
just not allow async reclaim while we're doing log replay. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The following commit enhanced the merge_extent_mapping() to reduce
fragment in extent map tree, but it can't handle case which existing
lies before map_start:
51f39 btrfs: Use right extent length when inserting overlap extent map.
[BUG]
When existing extent map's start is before map_start,
the em->len will be minus, which will corrupt the extent map and fail to
insert the new extent map.
This will happen when someone get a large extent map, but when it is
going to insert it into extent map tree, some one has already commit
some write and split the huge extent into small parts.
[REPRODUCER]
It is very easy to tiger using filebench with randomrw personality.
It is about 100% to reproduce when using 8G preallocated file in 60s
randonrw test.
[FIX]
This patch can now handle any existing extent position.
Since it does not directly use existing->start, now it will find the
previous and next extent around map_start.
So the old existing->start < map_start bug will never happen again.
[ENHANCE]
This patch will insert the best fitted extent map into extent map tree,
other than the oldest [map_start, map_start + sectorsize) or the
relatively newer but not perfect [map_start, existing->start).
The patch will first search existing extent that does not intersects with
the desired map range [map_start, map_start + len).
The existing extent will be either before or behind map_start, and based
on the existing extent, we can find out the previous and next extent
around map_start.
So the best fitted extent would be [prev->end, next->start).
For prev or next is not found, em->start would be prev->end and em->end
wold be next->start.
With this patch, the fragment in extent map tree should be reduced much
more than the 51f39 commit and reduce an unneeded extent map tree search.
An user reported this, it is because that lseek's SEEK_SET/SEEK_CUR/SEEK_END
allow a negative value for @offset, but btrfs's SEEK_DATA/SEEK_HOLE don't
prepare for that and convert the negative @offset into unsigned type,
so we get (end < start) warning.
The behaviour of a 'chattr -c' consists of getting the current flags,
clearing the FS_COMPR_FL bit and then sending the result to the set
flags ioctl - this means the bit FS_NOCOMP_FL isn't set in the flags
passed to the ioctl. This results in the compression property not being
cleared from the inode - it was cleared only if the bit FS_NOCOMP_FL
was set in the received flags.
Reproducer:
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt && cd /mnt
$ mkdir a
$ chattr +c a
$ touch a/file
$ lsattr a/file
--------c------- a/file
$ chattr -c a
$ touch a/file2
$ lsattr a/file2
--------c------- a/file2
$ lsattr -d a
---------------- a
Reported-by: Andreas Schneider <asn@cryptomilk.org> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
btrfs:32612
[stack snip]
btrfs_dev_replace_start()
btrfs_dev_replace_lock()
mutex_lock(dev_replace->lock) ###hold mutex(B)
btrfs_dev_replace_finishing()
btrfs_rm_dev_replace_blocked()
wait until percpu_counter_sum == 0 ###wait on bio_counter(A)
This bug can be triggered quite easily by the following test script:
http://pastebin.com/MQmb37Cy
This patch will fix the ABBA problem by calling
btrfs_dev_replace_unlock() before btrfs_rm_dev_replace_blocked().
The consistency of btrfs devices list and their superblocks is protected
by device_list_mutex, not btrfs_dev_replace_lock/unlock().
So it is safe the move btrfs_dev_replace_unlock() before
btrfs_rm_dev_replace_blocked().
Reported-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Cc: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
btrfs_drop_snapshot() leaves subvolume qgroup items on disk after
completion. This can cause problems with snapshot creation. If a new
snapshot tries to claim the deleted subvolumes id, btrfs will get -EEXIST
from add_qgroup_item() and go read-only. The following commands will
reproduce this problem (assume btrfs is on /dev/sda and is mounted at
/btrfs)
mkfs.btrfs -f /dev/sda
mount -t btrfs /dev/sda /btrfs/
btrfs quota enable /btrfs/
btrfs su sna /btrfs/ /btrfs/snap
btrfs su de /btrfs/snap
sleep 45
umount /btrfs/
mount -t btrfs /dev/sda /btrfs/
We can fix this by catching -EEXIST in add_qgroup_item() and
initializing the existing items. We have the problem of orphaned
relation items being on disk from an old snapshot but that is outside
the scope of this patch.
Signed-off-by: Mark Fasheh <mfasheh@suse.de> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The transaction thread may want to do more work, namely it pokes the
cleaner ktread that will start processing uncleaned subvols.
This can be triggered by user via the 'btrfs fi sync' command, otherwise
there was a delay up to 30 seconds before the cleaner started to clean
old snapshots.
Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM64 irq work self-IPI support depends on __smp_cross_call to point to
some relevant IRQ controller operations. This information should be
available after the call to init_IRQ().
lib/glob.c provides a new glob_match() function, with arguments in
(pattern, string) order. It replaced a private function with arguments
in (string, pattern) order, but I didn't swap the call site...
The result was the entire ATA blacklist was effectively disabled.
The lesson for today is "I f***ed up *how* badly *how* many months ago?",
er, I mean "Nobody Tests RC Kernels On Legacy Hardware".
This was not a subtle break, but it made it through an entire RC
cycle unreported, presumably because all the people doing testing
have full-featured hardware.
(FWIW, the reason for the argument swap was because fnmatch() does it that
way, and for a while implementing a full fnmatch() was being considered.)
Fixes: 428ac5fc056e0 (libata: Use glob_match from lib/glob.c) Reported-by: Steven Honeyman <stevenhoneyman@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=71371#c21 Signed-off-by: George Spelvin <linux@horizon.com> Tested-by: Steven Honeyman <stevenhoneyman@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Quark X1000 contains two designware derived 8250 serial ports.
Each port has a unique PCI configuration space consisting of
BAR0:UART BAR1:DMA respectively.
Unlike the standard 8250 the register width is 32 bits for RHR,IER etc
The Quark UART has a fundamental clock @ 44.2368 MHz allowing for a
bitrate of up to about 2.76 megabits per second.
Commit 92d585ef067d ("numa: fix NULL pointer access and memory
leak in unregister_one_node()") added kfree() of node struct in
unregister_one_node(). But node struct is freed by node_device_release()
which is called in unregister_node(). So by adding the kfree(),
node struct is freed two times.
While hot removing memory, the commit leads the following BUG_ON():
buf_0 and buf_1 in caam_hash_state are not next to each other.
Accessing buf_1 is incorrect from &buf_0 with an offset of only
size_of(buf_0). The same issue is also with buflen_0 and buflen_1
This full-speed USB device generates spurious remote wakeup event
as soon as USB_DEVICE_REMOTE_WAKEUP feature is set. As the result,
Linux can't enter system suspend and S0ix power saving modes once
this keyboard is used.
This patch tries to introduce USB_QUIRK_IGNORE_REMOTE_WAKEUP quirk.
With this quirk set, wakeup capability will be ignored during
device configure.
This patch could be back-ported to kernels as old as 2.6.39.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
if we don't make sure to kill the timer, it could
expire after we have already gated our clocks.
That will trigger a Data Abort exception because
we would try to access register while clock is gated.
Fix that bug.
Fixes 869c597 (usb: musb: dsps: add support for suspend and resume) Tested-by: Dave Gerlach <d-gerlach@ti.com> Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Added support for Ketra N1 wireless interface, which uses the
Silicon Labs' CP2104 USB to UART bridge with customized PID 8946.
Signed-off-by: Joe Savage <joe.savage@goketra.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
That commit causes more problem than fixes. Firstly, kfree()
should be called after usb_ep_dequeue() and secondly, the way
things are, we will try to dequeue a request that has already
completed much more frequently than one which is pending.
Cc: Li Jun <b47624@freescale.com> Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Besides the ASM1051 (*) needing sdev->no_report_opcodes = 1, it turns out that
the JMicron JMS567 also needs it to work properly with uas (usb-storage always
sets it). Since some of the scsi devs were not to keen on the idea to
outrightly set sdev->no_report_opcodes = 1 for all uas devices, so add a quirk
for this, and set it for the JMS567.
*) Which has become a non-issue since we've completely blacklisted uas on
the ASM1051 for other reasons
Reported-and-tested-by: Claudio Bizzarri <claudio.bizzarri@gmail.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we warned about a timeout on a hotplug command, we previously printed
the time between calls to pcie_write_cmd(), without accounting for any time
spent actually waiting. Consider this sequence:
pcie_write_cmd
pcie_wait_cmd
now = jiffies # T2
wait_event_timeout # we may wait here
if (timeout)
ctrl_info("Timeout on command issued %u msec ago",
jiffies_to_msecs(now - cmd_started))
We previously printed (T2 - T1), but that doesn't include the time spent in
wait_event_timeout().
Fix this by using the current jiffies value, not the one cached before
calling wait_event_timeout().
[bhelgaas: changelog, use current jiffies instead of adding timeout] Fixes: 40b960831cfa ("PCI: pciehp: Compute timeout from hotplug command start time") Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM irq work IPI support depends on SMP support. That information is
partly known at early boottime. Lets implement
arch_irq_work_has_interrupt() accordingly.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86 supports irq work self-IPIs when local apic is available. This is
partly known on runtime so lets implement arch_irq_work_has_interrupt()
accordingly.
This should be safely called after setup_arch().
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The nohz full kick, which restarts the tick when any resource depend
on it, can't be executed anywhere given the operation it does on timers.
If it is called from the scheduler or timers code, chances are that
we run into a deadlock.
This is why we run the nohz full kick from an irq work. That way we make
sure that the kick runs on a virgin context.
However if that's the case when irq work runs in its own dedicated
self-ipi, things are different for the big bunch of archs that don't
support the self triggered way. In order to support them, irq works are
also handled by the timer interrupt as fallback.
Now when irq works run on the timer interrupt, the context isn't blank.
More precisely, they can run in the context of the hrtimer that runs the
tick. But the nohz kick cancels and restarts this hrtimer and cancelling
an hrtimer from itself isn't allowed. This is why we run in an endless
loop:
To fix this we force non-lazy irq works to run on irq work self-IPIs
when available. That ability of the arch to trigger irq work self IPIs
is available with arch_irq_work_has_interrupt().
Reported-by: Catalin Iacob <iacobcatalin@gmail.com> Reported-by: Dave Jones <davej@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to copy exts->type when committing the change, otherwise
it would be always 0. This is a quick fix for -net and -stable,
for net-next tcf_exts will be removed.
Fixes: commit 33be627159913b094bb578e83 ("net_sched: act: use standard struct list_head") Reported-by: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit 6f2b6a3005b2c34c39f207a87667564f64f2f91a,
# 3c59x: Add dma error checking and recovery
the intent is to split out the mapping from the byte-swapping in order to
insert a dma_mapping_error() check.
Kinda this semantic patch:
// See http://coccinelle.lip6.fr/
//
// Beware, grouik-and-dirty!
@@
expression DEV, X, Y, Z;
@@
- cpu_to_le32(pci_map_single(DEV, X, Y, Z))
+ dma_addr_t addr = pci_map_single(DEV, X, Y, Z);
+ if (dma_mapping_error(&DEV->dev, addr))
+ /* snip */;
+ cpu_to_le32(addr)
However, the #else part (of the #if DO_ZEROCOPY test) is changed this way:
- cpu_to_le32(pci_map_single(DEV, X, Y, Z))
+ dma_addr_t addr = cpu_to_le32(pci_map_single(DEV, X, Y, Z));
// ^^^^^^^^^^^
// That mismatches the 3 other changes!
+ if (dma_mapping_error(&DEV->dev, addr))
+ /* snip */;
+ cpu_to_le32(addr)
Let's remove the leftover cpu_to_le32() for coherency.
v2: Better changelog.
v3: Add Acked-by
Fixes: 6f2b6a3005b2c34c39f207a87667564f64f2f91a
# 3c59x: Add dma error checking and recovery Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Sylvain "ythier" Hitier <sylvain.hitier@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently association restarts do not take into consideration the
state of the socket. When a restart happens, the current assocation
simply transitions into established state. This creates a condition
where a remote system, through a the restart procedure, may create a
local association that is no way reachable by user. The conditions
to trigger this are as follows:
1) Remote does not acknoledge some data causing data to remain
outstanding.
2) Local application calls close() on the socket. Since data
is still outstanding, the association is placed in SHUTDOWN_PENDING
state. However, the socket is closed.
3) The remote tries to create a new association, triggering a restart
on the local system. The association moves from SHUTDOWN_PENDING
to ESTABLISHED. At this point, it is no longer reachable by
any socket on the local system.
This patch addresses the above situation by moving the newly ESTABLISHED
association into SHUTDOWN-SENT state and bundling a SHUTDOWN after
the COOKIE-ACK chunk. This way, the restarted associate immidiately
enters the shutdown procedure and forces the termination of the
unreachable association.
Reported-by: David Laight <David.Laight@aculab.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After the packet is successfully sent, we should not touch the packet
as it may have been freed. This patch is based on the work done by
Long Li <longli@microsoft.com>.
David, please queue this up for stable.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When team_notify_peers and team_mcast_rejoin are called, they both reset
their respective .count_pending atomic variable. Then when the actual
worker function is executed, the variable is atomically decremented.
This pattern introduces a potential race condition where the
.count_pending rolls over and the worker function keeps rescheduling
until .count_pending decrements to zero again:
Instead of assigning a new value to .count_pending, use atomic_add to
tack-on the additional desired worker function invocations.
Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Fixes: fc423ff00df3a19554414ee ("team: add peer notification") Fixes: 492b200efdd20b8fcfdac87 ("team: add support for sending multicast rejoins") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Similar to commit bc23333ba11fb7f959b7e87e121122f5a0fbbca8 ("net:
bcmgenet: fix bcmgenet_put_tx_csum()"), we need to return the skb
pointer in case we had to reallocate the SKB headroom.
Fixes: 80105befdb4b8 ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In xmit path, we build a flowi6 which will be used for the output route lookup.
We are sending a GRE packet, neither IPv4 nor IPv6 encapsulated packet, thus the
protocol should be IPPROTO_GRE.
Fixes: c12b395a4664 ("gre: Support GRE over IPv6") Reported-by: Matthieu Ternisien d'Ouville <matthieu.tdo@6wind.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linus Torvalds [Sun, 5 Oct 2014 17:16:11 +0000 (10:16 -0700)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is a set of two small fixes, both to code which went in during
the merge window: cxgb4i has a scheduling in atomic bug in its new
ipv6 code and uas fails to work properly with the new scsi-mq code"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
[SCSI] uas: disable use of blk-mq I/O path
[SCSI] cxgb4i: avoid holding mutex in interrupt context
Linus Torvalds [Sat, 4 Oct 2014 16:32:47 +0000 (09:32 -0700)]
Merge tag 'tiny/kconfig-for-3.17' of https://git.kernel.org/pub/scm/linux/kernel/git/josh/linux
Pull kconfig fixes for tiny setups from Josh Triplett:
"Two Kconfig bugfixes for 3.17 related to tinification. These fixes
make the Kconfig "General Setup" menu much more usable"
* tag 'tiny/kconfig-for-3.17' of https://git.kernel.org/pub/scm/linux/kernel/git/josh/linux:
init/Kconfig: Fix HAVE_FUTEX_CMPXCHG to not break up the EXPERT menu
init/Kconfig: Hide printk log config if CONFIG_PRINTK=n
Josh Triplett [Fri, 3 Oct 2014 23:19:24 +0000 (16:19 -0700)]
init/Kconfig: Fix HAVE_FUTEX_CMPXCHG to not break up the EXPERT menu
commit 03b8c7b623c80af264c4c8d6111e5c6289933666 ("futex: Allow
architectures to skip futex_atomic_cmpxchg_inatomic() test") added the
HAVE_FUTEX_CMPXCHG symbol right below FUTEX. This placed it right in
the middle of the options for the EXPERT menu. However,
HAVE_FUTEX_CMPXCHG does not depend on EXPERT or FUTEX, so Kconfig stops
placing items in the EXPERT menu, and displays the remaining several
EXPERT items (starting with EPOLL) directly in the General Setup menu.
Since both users of HAVE_FUTEX_CMPXCHG only select it "if FUTEX", make
HAVE_FUTEX_CMPXCHG itself depend on FUTEX. With this change, the
subsequent items display as part of the EXPERT menu again; the EMBEDDED
menu now appears as the next top-level item in the General Setup menu,
which makes General Setup much shorter and more usable.
Linus Torvalds [Fri, 3 Oct 2014 20:31:57 +0000 (13:31 -0700)]
Merge tag 'trace-fixes-v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull trace ring buffer iterator fix from Steven Rostedt:
"While testing some new changes for 3.18, I kept hitting a bug every so
often in the ring buffer. At first I thought it had to do with some
of the changes I was working on, but then testing something else I
realized that the bug was in 3.17 itself. I ran several bisects as
the bug was not very reproducible, and finally came up with the commit
that I could reproduce easily within a few minutes, and without the
change I could run the tests over an hour without issue. The change
fit the bug and I figured out a fix. That bad commit was:
Commit 651e22f2701b "ring-buffer: Always reset iterator to reader page"
This commit fixed a bug, but in the process created another one. It
used the wrong value as the cached value that is used to see if things
changed while an iterator was in use. This made it look like a change
always happened, and could cause the iterator to go into an infinite
loop"
* tag 'trace-fixes-v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Fix infinite spin in reading buffer
Linus Torvalds [Fri, 3 Oct 2014 20:09:57 +0000 (13:09 -0700)]
Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs/smb3 fixes from Steve French:
"Fix for CIFS/SMB3 oops on reconnect during readpages (3.17 regression)
and for incorrectly closing file handle in symlink error cases"
* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
CIFS: Fix readpages retrying on reconnects
Fix problem recognizing symlinks
Linus Torvalds [Fri, 3 Oct 2014 15:31:14 +0000 (08:31 -0700)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Nothing too major or scary.
One i915 regression fix, nouveau has a tmds regression fix, along with
a regression fix for the runtime pm code for optimus laptops not
restoring the display hw correctly"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nouveau: make sure display hardware is reinitialised on runtime resume
drm/nouveau: punt fbcon resume out to a workqueue
drm/nouveau: fix regression on original nv50 board
drm/nv50/disp: fix dpms regression on certain boards
drm/i915: Flush the PTEs after updating them before suspend
The uas driver uses the block layer tag for USB3 stream IDs. With
blk-mq we can get larger tag numbers that the queue depth, which breaks
this assumption. A fix is under way for 3.18, but sits on top of
large changes so can't easily be backported. Set the disable_blk_mq
path so that a uas device can't easily crash the system when using
blk-mq for SCSI.
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Linus Torvalds [Fri, 3 Oct 2014 01:47:28 +0000 (18:47 -0700)]
Merge tag 'pm+acpi-3.17-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management fixes from Rafael Wysocki:
"These are three regression fixes (cpufreq core, pcc-cpufreq, i915 /
ACPI) and one trivial fix for a callback return value mismatch in the
cpufreq integrator driver.
Specifics:
- A recent cpufreq core fix went too far and introduced a regression
in the system suspend code path. Fix from Viresh Kumar.
- An ACPI-related commit in the i915 driver that fixed backlight
problems for some Thinkpads inadvertently broke a Dell machine (in
3.16). Fix from Aaron Lu.
- The pcc-cpufreq driver was broken during the 3.15 cycle by a commit
that put wait_event() under a spinlock by mistake. Fix that
(Rafael J Wysocki).
- The return value type of integrator_cpufreq_remove() is void, but
should be int. Fix from Arnd Bergmann"
* tag 'pm+acpi-3.17-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: update 'cpufreq_suspended' after stopping governors
ACPI / i915: Update the condition to ignore firmware backlight change request
cpufreq: integrator: fix integrator_cpufreq_remove return type
cpufreq: pcc-cpufreq: Fix wait_event() under spinlock
Andy Gross [Mon, 29 Sep 2014 22:00:51 +0000 (17:00 -0500)]
i2c: qup: Fix order of runtime pm initialization
The runtime pm calls need to be done before populating the children via the
i2c_add_adapter call. If this is not done, a child can run into issues trying
to do i2c read/writes due to the pm_runtime_sync failing.
Signed-off-by: Andy Gross <agross@codeaurora.org> Reviewed-by: Felipe Balbi <balbi@ti.com> Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
i2cdetect -q was broken (everything was a false positive, and no transfers were
actually being sent over i2c). The way it works is by sending a 0 length write
request and checking for NACK. This patch fixes the 0 length writes and actually
sends them.
Reported-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Alexandru M Stan <amstan@chromium.org> Tested-by: Doug Anderson <dianders@chromium.org> Tested-by: Max Schwarz <max.schwarz@online.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
Linus Torvalds [Thu, 2 Oct 2014 23:29:19 +0000 (16:29 -0700)]
Merge branch 'akpm' (fixes from Andrew Morton)
Merge fixes from Andrew Morton:
"5 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: page_alloc: fix zone allocation fairness on UP
perf: fix perf bug in fork()
MAINTAINERS: change git URL for mpc5xxx tree
mm: memcontrol: do not iterate uninitialized memcgs
ocfs2/dlm: should put mle when goto kill in dlm_assert_master_handler
Johannes Weiner [Thu, 2 Oct 2014 23:21:10 +0000 (16:21 -0700)]
mm: page_alloc: fix zone allocation fairness on UP
The zone allocation batches can easily underflow due to higher-order
allocations or spills to remote nodes. On SMP that's fine, because
underflows are expected from concurrency and dealt with by returning 0.
But on UP, zone_page_state will just return a wrapped unsigned long,
which will get past the <= 0 check and then consider the zone eligible
until its watermarks are hit.
Commit 3a025760fc15 ("mm: page_alloc: spill to remote nodes before
waking kswapd") already made the counter-resetting use
atomic_long_read() to accomodate underflows from remote spills, but it
didn't go all the way with it.
Make it clear that these batches are expected to go negative regardless
of concurrency, and use atomic_long_read() everywhere.
Fixes: 81c0a2bb515f ("mm: page_alloc: fair zone allocator policy") Reported-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Leon Romanovsky <leon@leon.nu> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: <stable@vger.kernel.org> [3.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Peter Zijlstra [Thu, 2 Oct 2014 23:17:02 +0000 (16:17 -0700)]
perf: fix perf bug in fork()
Oleg noticed that a cleanup by Sylvain actually uncovered a bug; by
calling perf_event_free_task() when failing sched_fork() we will not yet
have done the memset() on ->perf_event_ctxp[] and will therefore try and
'free' the inherited contexts, which are still in use by the parent
process. This is bad..
Johannes Weiner [Thu, 2 Oct 2014 23:16:57 +0000 (16:16 -0700)]
mm: memcontrol: do not iterate uninitialized memcgs
The cgroup iterators yield css objects that have not yet gone through
css_online(), but they are not complete memcgs at this point and so the
memcg iterators should not return them. Commit d8ad30559715 ("mm/memcg:
iteration skip memcgs not yet fully initialized") set out to implement
exactly this, but it uses CSS_ONLINE, a cgroup-internal flag that does
not meet the ordering requirements for memcg, and so the iterator may
skip over initialized groups, or return partially initialized memcgs.
The cgroup core can not reasonably provide a clear answer on whether the
object around the css has been fully initialized, as that depends on
controller-specific locking and lifetime rules. Thus, introduce a
memcg-specific flag that is set after the memcg has been initialized in
css_online(), and read before mem_cgroup_iter() callers access the memcg
members.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> [3.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / thirdparty / kernel / stable.git / log
