[The async read code was broadened to include uncached reads in 3.5, so
the mainline patch did not apply directly. This patch is just a backport
to account for that change.]
Jian found that when he ran fsx on a 32 bit arch with a large wsize the
process and one of the bdi writeback kthreads would sometimes deadlock
with a stack trace like this:
Each task would kmap part of its address array before getting stuck, but
not enough to actually issue the write.
This patch fixes this by serializing the marshal_iov operations for
async reads and writes. The idea here is to ensure that cifs
aggressively tries to populate a request before attempting to fulfill
another one. As soon as all of the pages are kmapped for a request, then
we can unlock and allow another one to proceed.
There's no need to do this serialization on non-CONFIG_HIGHMEM arches
however, so optimize all of this out when CONFIG_HIGHMEM isn't set.
Reported-by: Jian Li <jiali@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The rate of xusbxti clock is set in individual machine files.
The default value should be defined at the clock definition
and individual machine files should modify it if required.
Division by zero in kernel.
[<c0011849>] (unwind_backtrace+0x1/0x9c) from [<c022c663>] (Ldiv0+0x9/0x12)
[<c022c663>] (Ldiv0+0x9/0x12) from [<c001a3c3>] (s3c_setrate_clksrc+0x33/0x78)
[<c001a3c3>] (s3c_setrate_clksrc+0x33/0x78) from [<c0019e67>] (clk_set_rate+0x2f/0x78)
Signed-off-by: Tushar Behera <tushar.behera@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We can't guarantee that REQ_DISCARD on dm-mirror zeroes the data even if
the underlying disks support zero on discard. So this patch sets
ti->discard_zeroes_data_unsupported.
For example, if the mirror is in the process of resynchronizing, it may
happen that kcopyd reads a piece of data, then discard is sent on the
same area and then kcopyd writes the piece of data to another leg.
Consequently, the data is not zeroed.
This patch fixes a crash when a discard request is sent during mirror
recovery.
Firstly, some background. Generally, the following sequence happens during
mirror synchronization:
- function do_recovery is called
- do_recovery calls dm_rh_recovery_prepare
- dm_rh_recovery_prepare uses a semaphore to limit the number
simultaneously recovered regions (by default the semaphore value is 1,
so only one region at a time is recovered)
- dm_rh_recovery_prepare calls __rh_recovery_prepare,
__rh_recovery_prepare asks the log driver for the next region to
recover. Then, it sets the region state to DM_RH_RECOVERING. If there
are no pending I/Os on this region, the region is added to
quiesced_regions list. If there are pending I/Os, the region is not
added to any list. It is added to the quiesced_regions list later (by
dm_rh_dec function) when all I/Os finish.
- when the region is on quiesced_regions list, there are no I/Os in
flight on this region. The region is popped from the list in
dm_rh_recovery_start function. Then, a kcopyd job is started in the
recover function.
- when the kcopyd job finishes, recovery_complete is called. It calls
dm_rh_recovery_end. dm_rh_recovery_end adds the region to
recovered_regions or failed_recovered_regions list (depending on
whether the copy operation was successful or not).
The above mechanism assumes that if the region is in DM_RH_RECOVERING
state, no new I/Os are started on this region. When I/O is started,
dm_rh_inc_pending is called, which increases reg->pending count. When
I/O is finished, dm_rh_dec is called. It decreases reg->pending count.
If the count is zero and the region was in DM_RH_RECOVERING state,
dm_rh_dec adds it to the quiesced_regions list.
Consequently, if we call dm_rh_inc_pending/dm_rh_dec while the region is
in DM_RH_RECOVERING state, it could be added to quiesced_regions list
multiple times or it could be added to this list when kcopyd is copying
data (it is assumed that the region is not on any list while kcopyd does
its jobs). This results in memory corruption and crash.
There already exist bypasses for REQ_FLUSH requests: REQ_FLUSH requests
do not belong to any region, so they are always added to the sync list
in do_writes. dm_rh_inc_pending does not increase count for REQ_FLUSH
requests. In mirror_end_io, dm_rh_dec is never called for REQ_FLUSH
requests. These bypasses avoid the crash possibility described above.
These bypasses were improperly implemented for REQ_DISCARD when
the mirror target gained discard support in commit 5fc2ffeabb9ee0fc0e71ff16b49f34f0ed3d05b4 (dm raid1: support discard).
In do_writes, REQ_DISCARD requests is always added to the sync queue and
immediately dispatched (even if the region is in DM_RH_RECOVERING). However,
dm_rh_inc and dm_rh_dec is called for REQ_DISCARD resusts. So it violates the
rule that no I/Os are started on DM_RH_RECOVERING regions, and causes the list
corruption described above.
This patch changes it so that REQ_DISCARD requests follow the same path
as REQ_FLUSH. This avoids the crash.
When process_discard receives a partial discard that doesn't cover a
full block, it sends this discard down to that block. Unfortunately, the
block can be shared and the discard would corrupt the other snapshots
sharing this block.
This patch detects block sharing and ends the discard with success when
sending it to the shared block.
The above change means that if the device supports discard it can't be
guaranteed that a discard request zeroes data. Therefore, we set
ti->discard_zeroes_data_unsupported.
Do to OOM situations the ore might fail to allocate all resources
needed for IO of the full request. If some progress was possible
it would proceed with a partial/short request, for the sake of
forward progress.
Since this crashes NFS-core and exofs is just fine without it just
remove this contraption, and fail.
TODO:
Support real forward progress with some reserved allocations
of resources, such as mem pools and/or bio_sets
In RAID_5/6 We used to not permit an IO that it's end
byte is not stripe_size aligned and spans more than one stripe.
.i.e the caller must check if after submission the actual
transferred bytes is shorter, and would need to resubmit
a new IO with the remainder.
Exofs supports this, and NFS was supposed to support this
as well with it's short write mechanism. But late testing has
exposed a CRASH when this is used with none-RPC layout-drivers.
The change at NFS is deep and risky, in it's place the fix
at ORE to lift the limitation is actually clean and simple.
So here it is below.
The principal here is that in the case of unaligned IO on
both ends, beginning and end, we will send two read requests
one like old code, before the calculation of the first stripe,
and also a new site, before the calculation of the last stripe.
If any "boundary" is aligned or the complete IO is within a single
stripe. we do a single read like before.
The code is clean and simple by splitting the old _read_4_write
into 3 even parts:
1._read_4_write_first_stripe
2. _read_4_write_last_stripe
3. _read_4_write_execute
And calling 1+3 at the same place as before. 2+3 before last
stripe, and in the case of all in a single stripe then 1+2+3
is preformed additively.
Why did I not think of it before. Well I had a strike of
genius because I have stared at this code for 2 years, and did
not find this simple solution, til today. Not that I did not try.
This solution is much better for NFS than the previous supposedly
solution because the short write was dealt with out-of-band after
IO_done, which would cause for a seeky IO pattern where as in here
we execute in order. At both solutions we do 2 separate reads, only
here we do it within a single IO request. (And actually combine two
writes into a single submission)
NFS/exofs code need not change since the ORE API communicates the new
shorter length on return, what will happen is that this case would not
occur anymore.
hurray!!
[Stable this is an NFS bug since 3.2 Kernel should apply cleanly] Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UBIFS has a feature called "empty space fix-up" which is a quirk to work-around
limitations of dumb flasher programs. Namely, of those flashers that are unable
to skip NAND pages full of 0xFFs while flashing, resulting in empty space at
the end of half-filled eraseblocks to be unusable for UBIFS. This feature is
relatively new (introduced in v3.0).
The fix-up routine (fixup_free_space()) is executed only once at the very first
mount if the superblock has the 'space_fixup' flag set (can be done with -F
option of mkfs.ubifs). It basically reads all the UBIFS data and metadata and
writes it back to the same LEB. The routine assumes the image is pristine and
does not have anything in the journal.
There was a bug in 'fixup_free_space()' where it fixed up the log incorrectly.
All but one LEB of the log of a pristine file-system are empty. And one
contains just a commit start node. And 'fixup_free_space()' just unmapped this
LEB, which resulted in wiping the commit start node. As a result, some users
were unable to mount the file-system next time with the following symptom:
UBIFS error (pid 1): replay_log_leb: first log node at LEB 3:0 is not CS node
UBIFS error (pid 1): replay_log_leb: log error detected while replaying the log at LEB 3:0
The root-cause of this bug was that 'fixup_free_space()' wrongly assumed
that the beginning of empty space in the log head (c->lhead_offs) was known
on mount. However, it is not the case - it was always 0. UBIFS does not store
in it the master node and finds out by scanning the log on every mount.
The fix is simple - just pass commit start node size instead of 0 to
'fixup_leb()'.
The Sennheiser BTD500USB composit device requires the
HID_QUIRK_NOGET flag to be set for working proper. Without the
flag the device crashes during hid intialization.
This patch fixes a crash seen when large reads have their exchange
aborted by either timing out or being reset. Because the exchange
abort results in the seq pointer being set to NULL, because the
sequence is no longer valid, it must not be dereferenced. This
patch changes the function ft_get_task_tag to return ~0 if it is
unable to get the tag for this reason. Because the get_task_tag
interface provides no means of returning an error, this seems
like the best way to fix this issue at the moment.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit 6b43ae8a619d17c4935c3320d2ef9e92bdeed05d, I
introduced a bug that kept the STA_INS or STA_DEL bit
from being cleared from time_status via adjtimex()
without forcing STA_PLL first.
Usually once the STA_INS is set, it isn't cleared
until the leap second is applied, so its unlikely this
affected anyone. However during testing I noticed it
took some effort to cancel a leap second once STA_INS
was set.
Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1342156917-25092-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When NUMBER OF LOGICAL BLOCKS is 0, WRITE SAME is supposed to write
all the blocks from the specified LBA through the end of the device.
However, dev->transport->get_blocks(dev) (perhaps confusingly) returns
the last valid LBA rather than the number of blocks, so the correct
number of blocks to write starting with lba is
dev->transport->get_blocks(dev) - lba + 1
(nab: Backport roland's for-3.6 patch to for-3.5)
Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- instead of (PTR_ERR(file) < 0) just use IS_ERR(file)
- return -EINVAL instead of EINVAL
- all other error returns in target_scsi3_emulate_pr_out() use
"goto out" -- get rid of the one remaining straight "return."
Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We currently rely on being able to kmap all of the pages in an async
read or write request. If you're on a machine that has CONFIG_HIGHMEM
set then that kmap space is limited, sometimes to as low as 512 slots.
With 512 slots, we can only support up to a 2M r/wsize, and that's
assuming that we can get our greedy little hands on all of them. There
are other users however, so it's possible we'll end up stuck with a
size that large.
Since we can't handle a rsize or wsize larger than that currently, cap
those options at the number of kmap slots we have. We could consider
capping it even lower, but we currently default to a max of 1M. Might as
well allow those luddites on 32 bit arches enough rope to hang
themselves.
A more robust fix would be to teach the send and receive routines how
to contend with an array of pages so we don't need to marshal up a kvec
array at all. That's a fairly significant overhaul though, so we'll need
this limit in place until that's ready.
Reported-by: Jian Li <jiali@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we get back a FIND_FIRST/NEXT result, we have some info about the
dentry that we use to instantiate a new inode. We were ignoring and
discarding that info when we had an existing dentry in the cache.
Fix this by updating the inode in place when we find an existing dentry
and the uniqueid is the same.
Reported-and-Tested-by: Andrew Bartlett <abartlet@samba.org> Reported-by: Bill Robertson <bill_robertson@debortoli.com.au> Reported-by: Dion Edwards <dion_edwards@debortoli.com.au> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Added a 'reschedule_retry' call possibility at the end of
end_sync_write, but didn't add matching code at the end of
sync_request_write. So if the writes complete very quickly, or
scheduling makes it seem that way, then we can miss rescheduling
the request and the resync could hang.
md will refuse to stop an array if any other fd (or mounted fs) is
using it.
When any fs is unmounted of when the last open fd is closed all
pending IO will be flushed (e.g. sync_blockdev call in __blkdev_put)
so there will be no pending IO to worry about when the array is
stopped.
However in order to send the STOP_ARRAY ioctl to stop the array one
must first get and open fd on the block device.
If some fd is being used to write to the block device and it is closed
after mdadm open the block device, but before mdadm issues the
STOP_ARRAY ioctl, then there will be no last-close on the md device so
__blkdev_put will not call sync_blockdev.
If this happens, then IO can still be in-flight while md tears down
the array and bad things can happen (use-after-free and subsequent
havoc).
So in the case where do_md_stop is being called from an open file
descriptor, call sync_block after taking the mutex to ensure there
will be no new openers.
This is needed when setting a read-write device to read-only too.
The netlink commands and attributes, along with the socket structure
definitions need to be exported.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The leap second rework unearthed another issue of inconsistent data.
On timekeeping_resume() the timekeeper data is updated, but nothing
calls timekeeping_update(), so now the update code in the timer
interrupt sees stale values.
This has been the case before those changes, but then the timer
interrupt was using stale data as well so this went unnoticed for quite
some time.
Add the missing update call, so all the data is consistent everywhere.
Reported-by: Andreas Schwab <schwab@linux-m68k.org> Reported-and-tested-by: "Rafael J. Wysocki" <rjw@sisk.pl> Reported-and-tested-by: Martin Steigerwald <Martin@lichtvoll.de> Cc: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, Cc: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The update of the hrtimer base offsets on all cpus cannot be made
atomically from the timekeeper.lock held and interrupt disabled region
as smp function calls are not allowed there.
clock_was_set(), which enforces the update on all cpus, is called
either from preemptible process context in case of do_settimeofday()
or from the softirq context when the offset modification happened in
the timer interrupt itself due to a leap second.
In both cases there is a race window for an hrtimer interrupt between
dropping timekeeper lock, enabling interrupts and clock_was_set()
issuing the updates. Any interrupt which arrives in that window will
see the new time but operate on stale offsets.
So we need to make sure that an hrtimer interrupt always sees a
consistent state of time and offsets.
ktime_get_update_offsets() allows us to get the current monotonic time
and update the per cpu hrtimer base offsets from hrtimer_interrupt()
to capture a consistent state of monotonic time and the offsets. The
function replaces the existing ktime_get() calls in hrtimer_interrupt().
The overhead of the new function vs. ktime_get() is minimal as it just
adds two store operations.
This ensures that any changes to realtime or boottime offsets are
noticed and stored into the per-cpu hrtimer base structures, prior to
any hrtimer expiration and guarantees that timers are not expired early.
Signed-off-by: John Stultz <johnstul@us.ibm.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1341960205-56738-8-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To finally fix the infamous leap second issue and other race windows
caused by functions which change the offsets between the various time
bases (CLOCK_MONOTONIC, CLOCK_REALTIME and CLOCK_BOOTTIME) we need a
function which atomically gets the current monotonic time and updates
the offsets of CLOCK_REALTIME and CLOCK_BOOTTIME with minimalistic
overhead. The previous patch which provides ktime_t offsets allows us
to make this function almost as cheap as ktime_get() which is going to
be replaced in hrtimer_interrupt().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: John Stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/1341960205-56738-7-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to update the base offsets from this code and we need to do
that under base->lock. Move the lock held region around the
ktime_get() calls. The ktime_get() calls are going to be replaced with
a function which gets the time and the offsets atomically.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: John Stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/1341960205-56738-6-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to update the hrtimer clock offsets from the hrtimer interrupt
context. To avoid conversions from timespec to ktime_t maintain a
ktime_t based representation of those offsets in the timekeeper. This
puts the conversion overhead into the code which updates the
underlying offsets and provides fast accessible values in the hrtimer
interrupt.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1341960205-56738-4-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The timekeeping code misses an update of the hrtimer subsystem after a
leap second happened. Due to that timers based on CLOCK_REALTIME are
either expiring a second early or late depending on whether a leap
second has been inserted or deleted until an operation is initiated
which causes that update. Unless the update happens by some other
means this discrepancy between the timekeeping and the hrtimer data
stays forever and timers are expired either early or late.
The reported immediate workaround - $ data -s "`date`" - is causing a
call to clock_was_set() which updates the hrtimer data structures.
See: http://www.sheeri.com/content/mysql-and-leap-second-high-cpu-and-fix
Add the missing clock_was_set() call to update_wall_time() in case of
a leap second event. The actual update is deferred to softirq context
as the necessary smp function call cannot be invoked from hard
interrupt context.
Signed-off-by: John Stultz <johnstul@us.ibm.com> Reported-by: Jan Engelhardt <jengelh@inai.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1341960205-56738-3-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
clock_was_set() cannot be called from hard interrupt context because
it calls on_each_cpu().
For fixing the widely reported leap seconds issue it is necessary to
call it from hard interrupt context, i.e. the timer tick code, which
does the timekeeping updates.
Provide a new function which denotes it in the hrtimer cpu base
structure of the cpu on which it is called and raise the hrtimer
softirq. We then execute the clock_was_set() notificiation from
softirq context in run_hrtimer_softirq(). The hrtimer softirq is
rarely used, so polling the flag there is not a performance issue.
[ tglx: Made it depend on CONFIG_HIGH_RES_TIMERS. We really should get
rid of all this ifdeffery ASAP ]
Signed-off-by: John Stultz <johnstul@us.ibm.com> Reported-by: Jan Engelhardt <jengelh@inai.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Prarit Bhargava <prarit@redhat.com> Link: http://lkml.kernel.org/r/1341960205-56738-2-git-send-email-johnstul@us.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Don't validate interface combinations on a stopped
interface. Otherwise we might end up being able to
create a new interface with a certain type, but
won't be able to change an existing interface
into that type.
This also skips some other functions when
interface is stopped and changing interface type.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[Fixes regression introduced by cherry pick of 463454b5dbd8] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
clk_change_rate() is accessing parent's rate without checking
if the parent exists at all. In case of root clocks this will
cause NULL pointer dereference.
This patch follows what clk_calc_new_rates() does in such
situation.
I couldn't find the vendor ID in any of the online databases, but this
mat has a Pump It Up logo on the top side of the controller compartment,
and a disclaimer stating that Andamiro will not be liable on the bottom.
It was recently reported that moving a bonding device between network
namespaces causes warnings from /proc. It turns out after the move we
were trying to add and to remove the /proc/net/bonding entries from the
wrong network namespace.
Move the bonding /proc registration code into the NETDEV_REGISTER and
NETDEV_UNREGISTER events where the proc registration and unregistration
will always happen at the right time.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The bonding debugfs support has been broken in the presence of network
namespaces since it has been added. The debugfs support does not handle
multiple bonding devices with the same name in different network
namespaces.
I haven't had any bug reports, and I'm not interested in getting any.
Disable the debugfs support when network namespaces are enabled.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It was observed that during multiple reboots nfs hangs. The status of
receive descriptors shows that all the descriptors were in control of
CPU, and none were assigned to DMA.
Also the DMA status register confirmed that the Rx buffer is
unavailable.
This patch adds the fix for the same by adding the memory barriers to
ascertain that the all instructions before enabling the Rx or Tx DMA are
completed which involves the proper setting of the ownership bit in DMA
descriptors.
Signed-off-by: Deepak Sikri <deepak.sikri@st.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If association failed due to internal error (e.g. no
supported rates IE), we call ieee80211_destroy_assoc_data()
with assoc=true, while we actually reject the association.
This results in the BSSID not being zeroed out.
After passing assoc=false, we no longer have to call
sta_info_destroy_addr() explicitly. While on it, move
the "associated" message after the assoc_success check.
Signed-off-by: Eliad Peller <eliad@wizery.com> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When rpmsg drivers are built into the kernel, they must not initialize
before the rpmsg bus does, otherwise they'd trigger a BUG() in
drivers/base/driver.c line 169 (driver_register()).
To fix that, and to stop depending on arbitrary linkage ordering of
those built-in rpmsg drivers, we make the rpmsg bus initialize at
subsys_initcall.
When we remove a key, we put a key index which was supposed
to tell the fw that we are actually removing the key. But
instead the fw took that index as a valid index and messed
up the SRAM of the device.
This memory corruption on the device mangled the data of
the SCD. The impact on the user is that SCD queue 2 got
stuck after having removed keys.
Reported-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we only monitor while associated, the following
can happen:
- we're associated, and the queue stuck check
runs, setting the queue "touch" time to X
- we disassociate, stopping the monitoring,
which leaves the time set to X
- almost 2s later, we associate, and enqueue
a frame
- before the frame is transmitted, we monitor
for stuck queues, and find the time set to
X, although it is now later than X + 2000ms,
so we decide that the queue is stuck and
erroneously restart the device
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SYNCH bit and IV bit of RXCW register are sticky. Before examining these bits,
RXCW should be read twice to filter out one-time false events and have correct
values for these bits. Incorrect values of these bits in link check logic can
cause weird link stability issues if auto-negotiation fails.
Reported-by: Dean Nelson <dnelson@redhat.com> Signed-off-by: Tushar Dave <tushar.n.dave@intel.com> Reviewed-by: Bruce Allan <bruce.w.allan@intel.com> Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On rt2x00_dmastart() we increase index specified by Q_INDEX and on
rt2x00_dmadone() we increase index specified by Q_INDEX_DONE. So entries
between Q_INDEX_DONE and Q_INDEX are those we currently process in the
hardware. Entries between Q_INDEX and Q_INDEX_DONE are those we can
submit to the hardware.
According to that fix rt2x00usb_kick_queue(), as we need to submit RX
entries that are not processed by the hardware. It worked before only
for empty queue, otherwise was broken.
Note that for TX queues indexes ordering are ok. We need to kick entries
that have filled skb, but was not submitted to the hardware, i.e.
started from Q_INDEX_DONE and have ENTRY_DATA_PENDING bit set.
From practical standpoint this fixes RX queue stall, usually reproducible
in AP mode, like for example reported here:
https://bugzilla.redhat.com/show_bug.cgi?id=828824
Reported-and-tested-by: Franco Miceli <fmiceli@plan.ceibal.edu.uy> Reported-and-tested-by: Tom Horsley <horsley1953@gmail.com> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a parent and child process open the two ends of a fifo, and the
child immediately exits, the parent may receive a SIGCHLD before its
open() returns. In that case, we need to make sure that open() will
return successfully after the SIGCHLD handler returns, instead of
throwing EINTR or being restarted. Otherwise, the restarted open()
would incorrectly wait for a second partner on the other end.
The following test demonstrates the EINTR that was wrongly thrown from
the parent’s open(). Change .sa_flags = 0 to .sa_flags = SA_RESTART
to see a deadlock instead, in which the restarted open() waits for a
second reader that will never come. (On my systems, this happens
pretty reliably within about 5 to 500 iterations. Others report that
it manages to loop ~forever sometimes; YMMV.)
intel_ips driver spews the warning message
"ME failed to update for more than 1s, likely hung"
at each second endlessly on HP ProBook laptops with IronLake.
As this has never worked, better to blacklist the driver for now.
Commit d640113fe80e45ebd4a5b420b introduced a regression on SMP
systems where the processor core with ACPI id zero is disabled
(typically should be the case because of hyperthreading).
The regression got spread through stable kernels.
On 3.0.X it got introduced via 3.0.18.
Such platforms may be rare, but do exist.
Look out for a disabled processor with acpi_id 0 in dmesg:
ACPI: LAPIC (acpi_id[0x00] lapic_id[0x10] disabled)
This problem has been observed on a:
HP Proliant BL280c G6 blade
This patch restricts the introduced workaround to platforms
with nr_cpu_ids <= 1.
Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes a problem that can occur when a lone package object is
wrapped with an outer package object in order to conform to
the ACPI specification. Can affect these predefined names:
_ALR,_MLS,_PSS,_TRT,_TSS,_PRT,_HPX,_DLM,_CSD,_PSD,_TSD
Reported-by: Vlastimil Babka <caster@gentoo.org> Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This bug has been present ever since data-check was introduce
in 2.6.16. However it would only fire if a data-check were
done on a degraded array, which was only possible if the array
has 3 or more devices. This is certainly possible, but is quite
uncommon.
Since hot-replace was added in 3.3 it can happen more often as
the same condition can arise if not all possible replacements are
present.
The problem is that as soon as we submit the last read request, the
'r1_bio' structure could be freed at any time, so we really should
stop looking at it. If the last device is being read from we will
stop looking at it. However if the last device is not due to be read
from, we will still check the bio pointer in the r1_bio, but the
r1_bio might already be free.
So use the read_targets counter to make sure we stop looking for bios
to submit as soon as we have submitted them all.
This fix is suitable for any -stable kernel since 2.6.16.
We don't need to open code the divide function, just use div_u64 that
already exists and do the same job. While this is a straightforward
clean up, there is more to that, the real motivation for this.
While building on a cross compiling environment in armel, using gcc
4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5), I was getting the following build
error:
After investigating with objdump and hand built assembly version
generated with the compiler, I narrowed __aeabi_uldivmod as being
generated from the divide function. When nandsim.c is built with
-fno-inline-functions-called-once, that happens when
CONFIG_DEBUG_SECTION_MISMATCH is enabled, the do_div optimization in
arch/arm/include/asm/div64.h doesn't work as expected with the open
coded divide function: even if the do_div we are using doesn't have a
constant divisor, the compiler still includes the else parts of the
optimized do_div macro, and translates the divisions there to use
__aeabi_uldivmod, instead of only calling __do_div_asm -> __do_div64 and
optimizing/removing everything else out.
So to reproduce, gcc 4.6 plus CONFIG_DEBUG_SECTION_MISMATCH=y and
CONFIG_MTD_NAND_NANDSIM=m should do it, building on armel.
After this change, the compiler does the intended thing even with
-fno-inline-functions-called-once, and optimizes out as expected the
constant handling in the optimized do_div on arm. As this also avoids a
build issue, I'm marking for Stable, as I think is applicable for this
case.
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 080399aaaf35 ("block: don't mark buffers beyond end of disk as
mapped") exposed a bug in __getblk_slow that causes mount to hang as it
loops infinitely waiting for a buffer that lies beyond the end of the
disk to become uptodate.
The problem was initially reported by Torsten Hilbrich here:
bh = __find_get_block(bdev, block, size);
if (bh)
return bh;
ret = grow_buffers(bdev, block, size);
if (ret < 0)
return NULL;
if (ret == 0)
free_more_memory();
}
__find_get_block does not find the block, since it will not be marked as
mapped, and so grow_buffers is called to fill in the buffers for the
associated page. I believe the for (;;) loop is there primarily to
retry in the case of memory pressure keeping grow_buffers from
succeeding. However, we also continue to loop for other cases, like the
block lying beond the end of the disk. So, the fix I came up with is to
only loop when grow_buffers fails due to memory allocation issues
(return value of 0).
The attached patch was tested by myself, Torsten, and Rich, and was
found to resolve the problem in call cases.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Reported-and-Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Tested-by: Richard W.M. Jones <rjones@redhat.com> Reviewed-by: Josh Boyer <jwboyer@redhat.com>
[ Jens is on vacation, taking this directly - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We were accidentally losing one bit in the configuration register on
device initialization. It was reported to freeze one specific system
right away. Properly preserve all bits we don't explicitly want to
change in order to prevent that.
Commit 7a6f6c29d264cdd2fe0eb3d923217eed5f0ad134 (cx231xx: use
URB_NO_TRANSFER_DMA_MAP) was intended to avoid mapping the DMA buffer
for URB twice. This works for the URBs allocated with usb_alloc_urb(),
as those are allocated from cohernent DMA pools, but the flag was also
added for the VBI and audio URBs, which have a manually allocated area.
This leaves the random trash in the structure after allocation as the
DMA address, corrupting memory and preventing VBI and audio from
working. Letting the USB core map the buffers solves the problem.
Signed-off-by: David Dillow <dave@thedillows.org> Cc: Sri Deevi <srinivasa.deevi@conexant.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As ocfs2_fallocate() will invoke __ocfs2_change_file_space() with a NULL
as the first parameter (file), it may trigger a NULL pointer dereferrence
due to a missing check.
memblock_free_reserved_regions() calls memblock_free(), but
memblock_free() would double reserved.regions too, so we could free the
old range for reserved.regions.
Also tj said there is another bug which could be related to this.
| I don't think we're saving any noticeable
| amount by doing this "free - give it to page allocator - reserve
| again" dancing. We should just allocate regions aligned to page
| boundaries and free them later when memblock is no longer in use.
in that case, when DEBUG_PAGEALLOC, will get panic:
If page migration cannot charge the temporary page to the memcg,
migrate_pages() will return -ENOMEM. This isn't considered in memory
compaction however, and the loop continues to iterate over all
pageblocks trying to isolate and migrate pages. If a small number of
very large memcgs happen to be oom, however, these attempts will mostly
be futile leading to an enormous amout of cpu consumption due to the
page migration failures.
This patch will short circuit and fail memory compaction if
migrate_pages() returns -ENOMEM. COMPACT_PARTIAL is returned in case
some migrations were successful so that the page allocator will retry.
Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
WARNING: at irq/handle.c:146 handle_irq_event_percpu+0x19c/0x1b8()
irq 25 handler mxc_rtc_interrupt+0x0/0xac enabled interrupts
Modules linked in:
(unwind_backtrace+0x0/0xf0) from (warn_slowpath_common+0x4c/0x64)
(warn_slowpath_common+0x4c/0x64) from (warn_slowpath_fmt+0x30/0x40)
(warn_slowpath_fmt+0x30/0x40) from (handle_irq_event_percpu+0x19c/0x1b8)
(handle_irq_event_percpu+0x19c/0x1b8) from (handle_irq_event+0x28/0x38)
(handle_irq_event+0x28/0x38) from (handle_level_irq+0x80/0xc4)
(handle_level_irq+0x80/0xc4) from (generic_handle_irq+0x24/0x38)
(generic_handle_irq+0x24/0x38) from (handle_IRQ+0x30/0x84)
(handle_IRQ+0x30/0x84) from (avic_handle_irq+0x2c/0x4c)
(avic_handle_irq+0x2c/0x4c) from (__irq_svc+0x40/0x60)
Exception stack(0xc050bf60 to 0xc050bfa8)
bf60: 0000000100000000003c4208c0018e20c050a000c050a000c054a4c8c050a000
bf80: c05157a84117b36380503bb40000000001000000c050bfa8c0018e2cc000e808
bfa0: 60000013ffffffff
(__irq_svc+0x40/0x60) from (default_idle+0x1c/0x30)
(default_idle+0x1c/0x30) from (cpu_idle+0x68/0xa8)
(cpu_idle+0x68/0xa8) from (start_kernel+0x22c/0x26c)
kswapd_stop() is called to destroy the kswapd work thread when all memory
of a NUMA node has been offlined. But kswapd_stop() only terminates the
work thread without resetting NODE_DATA(nid)->kswapd to NULL. The stale
pointer will prevent kswapd_run() from creating a new work thread when
adding memory to the memory-less NUMA node again. Eventually the stale
pointer may cause invalid memory access.
An example stack dump as below. It's reproduced with 2.6.32, but latest
kernel has the same issue.
Commit 50ac23be ("staging:iio:adc:ad7606 add local define for chan_spec
structures.") accidentally removed the scale info_mask flag. This patch
adds it back again.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[herton: Backported to 3.4: info_mask was not used yet with another flag] Signed-off-by: Herton R. Krzesinski <herton@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In chunk_aligned_read() we are adding data_offset before calling
is_badblock. But is_badblock also adds data_offset, so that is bad.
So move the addition of data_offset to after the call to
is_badblock.
This bug was introduced by commit 31c176ecdf3563140e639
md/raid5: avoid reading from known bad blocks.
which first appeared in 3.0. So that patch is suitable for any
-stable kernel from 3.0.y onwards. However it will need minor
revision for most of those (as the comment didn't appear until
recently).
After banging my head against this for the past few months, I still
don't see how this could possible race under the premise that once an
irq bit is masked in PM_IMR and reset in PM_IIR it won't show up again
until we unmask it in PM_IMR.
Still, we have reports of this being seen in the wild. Now Bspec has
this little bit of lovely language in the PMIIR register:
Public SNB Docs, Vol3Part2, 2.5.14 "PMIIR":
"For each bit, the IIR can store a second pending interrupt if two or
more of the same interrupt conditions occur before the first condition
is cleared. Upon clearing the interrupt, the IIR bit will momentarily
go low, then return high to indicate there is another interrupt
pending."
Now if we presume that PMIMR only prevent new interrupts from being
queued, we could easily end up masking an interrupt and clearing it,
but the 2nd pending interrupt setting the bit in PMIIR right away
again. Which leads, the next time the irq handler runs, to hitting the
WARN.
Also, no bad side effects of this have ever been reported. And we've
tracked down our issues with the gpu turbo getting stuck to bogus
interrupt generation limits in th RPLIMIT register.
So let's just rip out this WARN as bogus and call it a day. The only
shallow thing here is that this 2-deep irq queue in the hw makes you
wonder how racy the windows irq handler is ...
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42907 Acked-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function, along with the registers and deferred work hander, are
all shared with SandyBridge, IvyBridge and their variants. So remove the
duplicate code into a single function.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Ben Widawsky <ben@bwidawsk.net> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust context; drop changes for Valley View] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dave Jones reported a kernel BUG at mm/slub.c:3474! triggered
by splice_shrink_spd() called from vmsplice_to_pipe()
commit 35f3d14dbbc5 (pipe: add support for shrinking and growing pipes)
added capability to adjust pipe->buffers.
Problem is some paths don't hold pipe mutex and assume pipe->buffers
doesn't change for their duration.
Fix this by adding nr_pages_max field in struct splice_pipe_desc, and
use it in place of pipe->buffers where appropriate.
splice_shrink_spd() loses its struct pipe_inode_info argument.
Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Tom Herbert <therbert@google.com> Tested-by: Dave Jones <davej@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
[bwh: Backported to 3.2:
- Adjust context in vmsplice_to_pipe()
- Update one more call to splice_shrink_spd(), from skb_splice_bits()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Driver doesn't report its supported cipher suites through cfg80211
interface. It still uses wext interface and probably will not work
through nl80211, but will at least correctly advertise supported
features.
Bug was reported by Omar Siam.
https://bugzilla.kernel.org/show_bug.cgi?id=43049
Signed-off-by: Stanislav Yakovlev <stas.yakovlev@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Cc: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There're several reasons that the vectors need to be validated:
- Return error when caller provides vectors whose num is greater than UIO_MAXIOV.
- Linearize part of skb when userspace provides vectors grater than MAX_SKB_FRAGS.
- Return error when userspace provides vectors whose total length may exceed
- MAX_SKB_FRAGS * PAGE_SIZE.
Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Cc: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
BUG: sleeping function called from invalid context at kernel/workqueue.c:2547
in_atomic(): 1, irqs_disabled(): 0, pid: 629, name: wpa_supplicant
2 locks held by wpa_supplicant/629:
#0: (rtnl_mutex){+.+.+.}, at: [<c08b2b84>] rtnl_lock+0x14/0x20
#1: (&trigger->leddev_list_lock){.+.?..}, at: [<c0867f41>] led_trigger_event+0x21/0x80
Pid: 629, comm: wpa_supplicant Not tainted 3.3.0-0.rc3.git5.1.fc17.i686
Call Trace:
[<c046a9f6>] __might_sleep+0x126/0x1d0
[<c0457d6c>] wait_on_work+0x2c/0x1d0
[<c045a09a>] __cancel_work_timer+0x6a/0x120
[<c045a160>] cancel_delayed_work_sync+0x10/0x20
[<f7dd3c22>] rtl8187_led_brightness_set+0x82/0xf0 [rtl8187]
[<c0867f7c>] led_trigger_event+0x5c/0x80
[<f7ff5e6d>] ieee80211_led_radio+0x1d/0x40 [mac80211]
[<f7ff3583>] ieee80211_stop_device+0x13/0x230 [mac80211]
Removing _sync is ok, because if led_on work is currently running
it will be finished before led_off work start to perform, since
they are always queued on the same mac80211 local->workqueue.
In the x86 32bit PAE CONFIG_TRANSPARENT_HUGEPAGE=y case while holding the
mmap_sem for reading, cmpxchg8b cannot be used to read pmd contents under
Xen.
So instead of dealing only with "consistent" pmdvals in
pmd_none_or_trans_huge_or_clear_bad() (which would be conceptually
simpler) we let pmd_none_or_trans_huge_or_clear_bad() deal with pmdvals
where the low 32bit and high 32bit could be inconsistent (to avoid having
to use cmpxchg8b).
The only guarantee we get from pmd_read_atomic is that if the low part of
the pmd was found null, the high part will be null too (so the pmd will be
considered unstable). And if the low part of the pmd is found "stable"
later, then it means the whole pmd was read atomically (because after a
pmd is stable, neither MADV_DONTNEED nor page faults can alter it anymore,
and we read the high part after the low part).
In the 32bit PAE x86 case, it is enough to read the low part of the pmdval
atomically to declare the pmd as "stable" and that's true for THP and no
THP, furthermore in the THP case we also have a barrier() that will
prevent any inconsistent pmdvals to be cached by a later re-read of the
*pmd.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Jonathan Nieder <jrnieder@gmail.com> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When holding the mmap_sem for reading, pmd_offset_map_lock should only
run on a pmd_t that has been read atomically from the pmdp pointer,
otherwise we may read only half of it leading to this crash.
This should be a longstanding bug affecting x86 32bit PAE without THP.
Only archs with 64bit large pmd_t and 32bit unsigned long should be
affected.
With THP enabled the barrier() in pmd_none_or_trans_huge_or_clear_bad()
would partly hide the bug when the pmd transition from none to stable,
by forcing a re-read of the *pmd in pmd_offset_map_lock, but when THP is
enabled a new set of problem arises by the fact could then transition
freely in any of the none, pmd_trans_huge or pmd_trans_stable states.
So making the barrier in pmd_none_or_trans_huge_or_clear_bad()
unconditional isn't good idea and it would be a flakey solution.
This should be fully fixed by introducing a pmd_read_atomic that reads
the pmd in order with THP disabled, or by reading the pmd atomically
with cmpxchg8b with THP enabled.
Luckily this new race condition only triggers in the places that must
already be covered by pmd_none_or_trans_huge_or_clear_bad() so the fix
is localized there but this bug is not related to THP.
NOTE: this can trigger on x86 32bit systems with PAE enabled with more
than 4G of ram, otherwise the high part of the pmd will never risk to be
truncated because it would be zero at all times, in turn so hiding the
SMP race.
This bug was discovered and fully debugged by Ulrich, quote:
----
[..]
pmd_none_or_trans_huge_or_clear_bad() loads the content of edx and
eax.
496 static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t
*pmd)
497 {
498 /* depend on compiler for an atomic pmd read */
499 pmd_t pmdval = *pmd;
Please note that the PMD is not read atomically. These are two "mov"
instructions where the high order bits of the PMD entry are fetched
first. Hence, the above machine code is prone to the following race.
- The PMD entry {high|low} is 0x0000000000000000.
The "mov" at 0xc0507a84 loads 0x00000000 into edx.
- A page fault (on another CPU) sneaks in between the two "mov"
instructions and instantiates the PMD.
- The PMD entry {high|low} is now 0x00000003fda38067.
The "mov" at 0xc0507a8e loads 0xfda38067 into eax.
----
Reported-by: Ulrich Obergfell <uobergfe@redhat.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 3a2923e83c introduced a bug when a corrupt descriptor
is encountered - although the following descriptor is discarded
and returned to the queue for reuse the associated frame is
also returned for processing. This leads to a panic:
5906 devices also need the short DMA fragment workaround. This patch
makes the necessary change.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com> Tested-by: Christian Kujau <lists@nerdbynature.de> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There isn't locking setting STRIPE_DELAYED and STRIPE_PREREAD_ACTIVE bits, but
the two bits have relationship. A delayed stripe can be moved to hold list only
when preread active stripe count is below IO_THRESHOLD. If a stripe has both
the bits set, such stripe will be in delayed list and preread count not 0,
which will make such stripe never leave delayed list.
When debugging is disabled, the event log functions aren't
functional in the way that the debugfs file expects. This
leads to the debugfs access crashing. Since the event log
functions aren't functional then, remove the debugfs file
when CONFIG_IWLWIFI_DEBUG is not set.
Reported-by: Lekensteyn <lekensteyn@gmail.com> Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
went in and changed the TX/RX enable logic, but now
the conditions for stopping and restarting the queues
were different so that now, if the AP changes between
20/40 MHz bandwidth, it can happen that we stop but
never restart the queues. This breaks the connection
and the module actually has to be reloaded to get it
back to work.
Fix this by making sure the queues are always started
when they were stopped.
In case of destroying mount namespace on child reaper exit, nsproxy is zeroed
to the point already. So, dereferencing of it is invalid.
This patch hard-code "init_net" for all network namespace references for NFS
callback services. This will be fixed with proper NFS callback
containerization.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The idea is to separate service destruction and per-net operations,
because these are two different things and the mix looks ugly.
Notes:
1) For NFS server this patch looks ugly (sorry for that). But these
place will be rewritten soon during NFSd containerization.
2) LockD per-net counter increase int lockd_up() was moved prior to
make_socks() to make lockd_down_net() call safe in case of error.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new routine is responsible for service registration in a specified
network context.
The idea is to separate service creation from per-net operations.
Note also: since registering service with svc_bind() can fail, the
service will be destroyed and during destruction it will try to
unregister itself from rpcbind. In this case unregistration has to be
skipped.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
v2: dereference of most probably already released nlm_host removed in
nlmclnt_done() and reclaimer().
These routines are called from locks reclaimer() kernel thread. This thread
works in "init_net" network context and currently relays on persence on lockd
thread and it's per-net resources. Thus lockd_up() and lockd_down() can't relay
on current network context. So let's pass corrent one into them.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds support for the iPad to the ipheth driver.
(product id = 0x129a)
Signed-off-by: Davide Gerhard <rainbow@irh.it> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Quite a few ASUS computers experience a nasty problem, related to the
EHCI controllers, when going into system suspend. It was observed
that the problem didn't occur if the controllers were not put into the
D3 power state before starting the suspend, and commit 151b61284776be2d6f02d48c23c3625678960b97 (USB: EHCI: fix crash during
suspend on ASUS computers) was created to do this.
It turned out this approach messed up other computers that didn't have
the problem -- it prevented USB wakeup from working. Consequently
commit c2fb8a3fa25513de8fedb38509b1f15a5bbee47b (USB: add
NO_D3_DURING_SLEEP flag and revert 151b61284776be2) was merged; it
reverted the earlier commit and added a whitelist of known good board
names.
Now we know the actual cause of the problem. Thanks to AceLan Kao for
tracking it down.
According to him, an engineer at ASUS explained that some of their
BIOSes contain a bug that was added in an attempt to work around a
problem in early versions of Windows. When the computer goes into S3
suspend, the BIOS tries to verify that the EHCI controllers were first
quiesced by the OS. Nothing's wrong with this, but the BIOS does it
by checking that the PCI COMMAND registers contain 0 without checking
the controllers' power state. If the register isn't 0, the BIOS
assumes the controller needs to be quiesced and tries to do so. This
involves making various MMIO accesses to the controller, which don't
work very well if the controller is already in D3. The end result is
a system hang or memory corruption.
Since the value in the PCI COMMAND register doesn't matter once the
controller has been suspended, and since the value will be restored
anyway when the controller is resumed, we can work around the BIOS bug
simply by setting the register to 0 during system suspend. This patch
(as1590) does so and also reverts the second commit mentioned above,
which is now unnecessary.
In theory we could do this for every PCI device. However to avoid
introducing new problems, the patch restricts itself to EHCI host
controllers.
Finally the affected systems can suspend with USB wakeup working
properly.
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=37632
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=42728 Based-on-patch-by: AceLan Kao <acelan.kao@canonical.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Dâniel Fraga <fragabr@gmail.com> Tested-by: Javier Marcet <jmarcet@gmail.com> Tested-by: Andrey Rahmatullin <wrar@wrar.name> Tested-by: Oleksij Rempel <bug-track@fisher-privat.net> Tested-by: Pavel Pisa <pisa@cmp.felk.cvut.cz> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Microsoft LifeChat 3000 USB headset was causing a very reproducible
hang whenever it was plugged in. At first, I thought the host
controller was producing bad transfer events, because the log was filled
with errors like:
xhci_hcd 0000:00:14.0: ERROR Transfer event TRB DMA ptr not part of current TD
However, it turned out to be an xHCI driver bug in the ring expansion
patches. The bug is triggered When there are two ring segments, and a
TD that ends just before a link TRB, like so:
______________ _____________
| | ---> | setup TRB B |
______________ | _____________
| | | | data TRB B |
______________ | _____________
| setup TRB A | <-- deq | | data TRB B |
______________ | _____________
| data TRB A | | | | <-- enq, deq''
______________ | _____________
| status TRB A | | | |
______________ | _____________
| link TRB |--------------- | link TRB |
_____________ <--- deq' _____________
TD A (the first control transfer) stalls on the data phase. That halts
the ring. The xHCI driver moves the hardware dequeue pointer to the
first TRB after the stalled transfer, which happens to be the link TRB.
Once the Set TR dequeue pointer command completes, the function
update_ring_for_set_deq_completion runs. That function is supposed to
update the xHCI driver's dequeue pointer to match the internal hardware
dequeue pointer. On the first call this would work fine, and the
software dequeue pointer would move to deq'.
However, if the transfer immediately after that stalled (TD B in this
case), another Set TR Dequeue command would be issued. That would move
the hardware dequeue pointer to deq''. Once that command completed,
update_ring_for_set_deq_completion would run again.
The original code would unconditionally increment the software dequeue
pointer, which moved the pointer off the ring segment into la-la-land.
The while loop would happy increment the dequeue pointer (possibly
wrapping it) until it matched the hardware pointer value.
The while loop would also access all the memory in between the first
ring segment and the second ring segment to determine if it was a link
TRB. This could cause general protection faults, although it was
unlikely because the ring segments came from a DMA pool, and would often
have consecutive memory addresses.
If nothing in that space looked like a link TRB, the deq_seg pointer for
the ring would remain on the first segment. Thus, the deq_seg and the
software dequeue pointer would get out of sync.
When the next transfer event came in after the stalled transfer, the
xHCI driver code would attempt to convert the software dequeue pointer
into a DMA address in order to compare the DMA address for the completed
transfer. Since the deq_seg and the dequeue pointer were out of sync,
xhci_trb_virt_to_dma would return NULL.
The transfer event would get ignored, the transfer would eventually
timeout, and we would mistakenly convert the finished transfer to no-op
TRBs. Some kernel driver (maybe xHCI?) would then get stuck in an
infinite loop in interrupt context, and the whole machine would hang.
This patch should be backported to kernels as old as 3.4, that contain
the commit b008df60c6369ba0290fa7daa177375407a12e07 "xHCI: count free
TRBs on transfer ring"
The host controller port status register supports CAS (Cold Attach
Status) bit. This bit could be set when USB3.0 device is connected
when system is in Sx state. When the system wakes to S0 this port
status with CAS bit is reported and this port can't be used by any
device.
When CAS bit is set the port should be reset by warm reset. This
was not supported by xhci driver.
The issue was found when pendrive was connected to suspended
platform. The link state of "Compliance Mode" was reported together
with CAS bit. This link state was also not supported by xhci and
core/hub.c.
The CAS bit is defined only for xhci root hub port and it is
not supported on regular hubs. The link status is used to force
warm reset on port. Make the USB core issue a warm reset when port
is in ether the 'inactive' or 'compliance mode'. Change the xHCI driver
to report 'compliance mode' when the CAS is set. This force warm reset
on the root hub port.
This patch should be backported to stable kernels as old as 3.2, that
contain the commit 10d674a82e553cb8a1f41027bb3c3e309b3f6804 "USB: When
hot reset for USB3 fails, try warm reset."
Switches into a composite device by ejecting the initial
driver CD. The four interfaces are: QCDM, AT, QMI/wwan
and mass storage. Let this driver manage the two serial
interfaces:
projects / karo-tx-linux.git / log