Clang complains that we are assigning a variable to itself. This should
be using bad_sectors like the similar earlier check does.
Bug has been present since 3.1-rc1. It is minor but could
conceivably cause corruption or other bad behaviour.
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In some cases array are started in 'read-auto' state where in
nothing gets written to any device until the array is written
to. The purpose of this is to make accidental auto-assembly
of the wrong arrays less of a risk, and to allow arrays to be
started to read suspend-to-disk images without actually changing
anything (as might happen if the array were dirty and a
resync seemed necessary).
Explicitly writing the 'sync_action' for a read-auto array currently
doesn't clear the read-auto state, so the sync action doesn't
happen, which can be confusing.
So allow any successful write to sync_action to clear any read-auto
state.
Reported-by: Alexander Kühn <alexander.kuehn@nagilum.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Now that multiple threads can handle stripes, it is safer to
use an atomic64_t for resync_mismatches, to avoid update races.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This patch originated from Hiroaki SHIMODA but has been modified
by Intel with some minor cleanups and additional commit log text.
Denys Fedoryshchenko and others reported Tx stalls on e1000e with
BQL enabled. Issue was root caused to hardware delays. They were
introduced because some of the e1000e hardware with transmit
writeback bursting enabled, waits until the driver does an
explict flush OR there are WTHRESH descriptors to write back.
Sometimes the delays in question were on the order of seconds,
causing visible lag for ssh sessions and unacceptable tx
completion latency, especially for BQL enabled kernels.
To avoid possible Tx stalls, change WTHRESH back to 1.
The current plan is to investigate a method for re-enabling
WTHRESH while not harming BQL, but those patches will be later
for net-next if they work.
please enqueue for stable since v3.3 as this bug was introduced in
commit 3f0cfa3bc1
Author: Tom Herbert <therbert@google.com>
Date: Mon Nov 28 16:33:16 2011 +0000
e1000e: Support for byte queue limits
Changes to e1000e to use byte queue limits.
Reported-by: Denys Fedoryshchenko <denys@visp.net.lb>
Tested-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
CC: eric.dumazet@gmail.com
CC: therbert@google.com
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Marc Kleine-Budde says:
====================
this pull request for net, i.e. the v3.7 release cycle, contains the patch by
David Howells to move the UAPI related headers for the CAN subsystem.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse complains about RTA_MARK which is should be host order according
to include file and usage in iproute.
net/ipv4/route.c:2223:46: warning: incorrect type in argument 3 (different base types)
net/ipv4/route.c:2223:46: expected restricted __be32 [usertype] value
net/ipv4/route.c:2223:46: got unsigned int [unsigned] [usertype] flowic_mark
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An SKB paged fragment can consist of a compound page with order > 0.
However the netchannel protocol deals only in PAGE_SIZE frames.
Handle this in netbk_gop_frag_copy and xen_netbk_count_skb_slots by
iterating over the frames which make up the page.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Konrad Rzeszutek Wilk <konrad@kernel.org>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If lower layer driver leaves the ip header in the skb fragment, it needs to
be first pulled into skb->data before inspecting ip header length or ip version
number.
Signed-off-by: Sarveshwar Bandi <sarveshwar.bandi@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
"protos" is an array of unsigned longs and "i" is the number of bits in
an unsigned long so we need to use 1UL as well to prevent the shift
from wrapping around.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
to_read and to_write are part of the result of analysing
a stripe before handling it.
Their use is to avoid some loops and tests if the values are
known to be zero. Thus it is not a problem if they are a
little bit larger than they should be.
So decrementing them in handle_failed_stripe serves little value, and
due to races it could cause some loops to be skipped incorrectly.
So remove those decrements.
Reported-by: "Jianpeng Ma" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
The pr_debug in add_stripe_bio could race with something
changing *bip, so it is best to hold the lock until
after the pr_debug.
Reported-by: "Jianpeng Ma" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We really should hold the stripe_lock while accessing
'toread' else we could race with add_stripe_bio and corrupt
a list.
Reported-by: "Jianpeng Ma" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We want to avoid zero discarded dev page, because it's useless for discard.
But if we don't zero it, another read/write hit such page in the cache and will
get inconsistent data.
To avoid zero the page, we don't set R5_UPTODATE flag after construction is
done. In this way, discard write request is still issued and finished, but read
will not hit the page. If the stripe gets accessed soon, we need reread the
stripe, but since the chance is low, the reread isn't a big deal.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Discard for raid4/5/6 has limitation. If discard request size is
small, we do discard for one disk, but we need calculate parity and
write parity disk. To correctly calculate parity, zero_after_discard
must be guaranteed. Even it's true, we need do discard for one disk
but write another disks, which makes the parity disks wear out
fast. This doesn't make sense. So an efficient discard for raid4/5/6
should discard all data disks and parity disks, which requires the
write pattern to be (A, A+chunk_size, A+chunk_size*2...). If A's size
is smaller than chunk_size, such pattern is almost impossible in
practice. So in this patch, I only handle the case that A's size
equals to chunk_size. That is discard request should be aligned to
stripe size and its size is multiple of stripe size.
Since we can only handle request with specific alignment and size (or
part of the request fitting stripes), we can't guarantee
zero_after_discard even zero_after_discard is true in low level
drives.
The block layer doesn't send down correctly aligned requests even
correct discard alignment is set, so I must filter out.
For raid4/5/6 parity calculation, if data is 0, parity is 0. So if
zero_after_discard is true for all disks, data is consistent after
discard. Otherwise, data might be lost. Let's consider a scenario:
discard a stripe, write data to one disk and write parity disk. The
stripe could be still inconsistent till then depending on using data
from other data disks or parity disks to calculate new parity. If the
disk is broken, we can't restore it. So in this patch, we only enable
discard support if all disks have zero_after_discard.
If discard fails in one disk, we face the similar inconsistent issue
above. The patch will make discard follow the same path as normal
write request. If discard fails, a resync will be scheduled to make
the data consistent. This isn't good to have extra writes, but data
consistency is important.
If a subsequent read/write request hits raid5 cache of a discarded
stripe, the discarded dev page should have zero filled, so the data is
consistent. This patch will always zero dev page for discarded request
stripe. This isn't optimal because discard request doesn't need such
payload. Next patch will avoid it.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When we get a read error, we arrange for raid1d to handle it.
Currently we release the reference on the device. This can result
in
conf->mirrors[read_disk].rdev
being NULL in fix_read_error, if the device happens to get removed
before the read error is handled.
So instead keep the reference until the read error has been fully
handled.
Reported-by: hank <pyu@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This patch replaces list_for_each_continue_rcu() with
list_for_each_entry_continue_rcu() to save a few lines
of code and allow removing list_for_each_continue_rcu().
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: NeilBrown <neilb@suse.de>
There are two table arguments that can be given to a DM RAID target
that control whether the array is forced to (re)synchronize or skip
initialization: "sync" and "nosync". When "sync" is given, we set
mddev->recovery_cp to 0 in order to cause the device to resynchronize.
This is insufficient if there is a bitmap in use, because the array
will simply look at the bitmap and see that there is no recovery
necessary.
The fix is to skip over the loading of the superblocks when "sync" is
given, causing new superblocks to be written that will force the array
to go through initialization (i.e. synchronization).
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If vxlan is created and the ifindex is passed; there are two cases which
are incorrectly handled by the existing code. The ifindex could be zero
(i.e. no device) or there could be no device with that ifindex.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vxlan was trying to use postpull_rcsum to allow receive checksum
offload to work on drivers using CHECKSUM_COMPLETE method. But this
doesn't work correctly. Just force full receive checksum on received
packet.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tell upper layer protocols to allocate skb with additional headroom.
This avoids allocation and copy in local packet sends.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
VXLAN bases source UDP port based on flow to help the
receiver to be able to load balance based on outer header flow.
This patch restricts the port range to the normal UDP local
ports, and allows overriding via configuration.
It also uses jhash of Ethernet header when looking at flows
with out know L3 header.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When tunnelling a skb, associate it with the tunnel socket.
This allows parameters set on tunnel socket (like multicast loop
flag), to be picked up by ip_output.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Select source address for VXLAN packet based on route destination
and don't lie to route code. VXLAN is not GRE.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Shift was wrong direction causing packets to hash based on
other parts of the ethernet header, not the address.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move code to find destination to a small function.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The !CONFIG_OF stubs aren't static so if multiple files include the
header with this configuration then the linker will see multiple
definitions of the stubs.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
DM RAID: Fix comparison of index and quantity for "rebuild" parameter
The "rebuild" parameter takes an index argument that starts counting from
zero. The conditional used to validate the index was using '>' rather than
'>=', leaving the door open for an index value that would be 1 too large.
Reported-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
DM RAID: Add code to validate replacement slots for RAID10 arrays
RAID10 can handle 'copies - 1' failures for each mirror group. This code
ensures the user has provided a valid array - one whose devices specified for
rebuild do not exceed the amount of redundancy available.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
DM RAID: Move chunk of code to it's own function
The code that checks whether device replacements/rebuilds are possible given
a specific RAID type is moved to it's own function. It will further expand
when the code to check RAID10 is added. A separate function makes it easier
to read.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
MD RAID10: Fix a couple potential kernel panics if RAID10 is used by dm-raid
When device-mapper uses the RAID10 personality through dm-raid.c, there is no
'gendisk' structure in mddev and some sysfs information is also not populated.
This patch avoids touching those non-existent structures.
Signed-off-by: Jonathan Brassow <jbrassow@rehdat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Some ioctls don't need to take the mutex and doing so can cause
a delay as it is held during super-block update.
So move those ioctls out of the mutex and rely on rcu locking
to ensure we don't access stale data.
Signed-off-by: NeilBrown <neilb@suse.de>
Change the thread parameter, so the thread can carry extra info. Next patch
will use it.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
It is weird to display IPv4 address in %x format, what's more,
IPv6 address is disaplayed in human-readable format too. So,
make it human-readable.
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ETH_ZLEN is too small for IPv6, so this default value is not
suitable.
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For IPv6, sizeof(struct ipv6hdr) = 40, thus the following
expression will result negative:
datalen = pkt_dev->cur_pkt_size - 14 -
sizeof(struct ipv6hdr) - sizeof(struct udphdr) -
pkt_dev->pkt_overhead;
And, the check "if (datalen < sizeof(struct pktgen_hdr))" will be
passed as "datalen" is promoted to unsigned, therefore will cause
a crash later.
This is a quick fix by checking if "datalen" is negative. The following
patch will increase the default value of 'min_pkt_size' for IPv6.
This bug should exist for a long time, so Cc -stable too.
Cc: <stable@vger.kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
queuing writes to the md thread means that all requests go through the
one processor which may not be able to keep up with very high request
rates.
So use the plugging infrastructure to submit all requests on unplug.
If a 'schedule' is needed, we fall back on the old approach of handing
the requests to the thread for it to handle.
This is nearly identical to a recent patch which provided similar
functionality to RAID1.
Signed-off-by: NeilBrown <neilb@suse.de>
This makes md raid 10 support TRIM.
If one disk supports discard and another not, or one has
discard_zero_data and another not, there could be inconsistent between
data from such disks. But this should not matter, discarded data is
useless. This will add extra copy in rebuild though.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This makes md raid 1 support TRIM.
If one disk supports discard and another not, or one has discard_zero_data and
another not, there could be inconsistent between data from such disks. But this
should not matter, discarded data is useless. This will add extra copy in rebuild
though.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
According to the comment in linear_stop function
rcu_dereference in linear_start and linear_stop functions
occurs under reconfig_mutex. The patch represents this
agreement in code and prevents lockdep complaint.
Found by Linux Driver Verification project (linuxtesting.org)
Signed-off-by: Denis Efremov <yefremov.denis@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Pull i2c-embedded changes from Wolfram Sang:
"The changes for i2c-embedded include:
- massive rework of the omap driver
- massive rework of the at91 driver. In fact, the old driver gets
removed; I am okay with this approach since the old driver was
depending on BROKEN and its limitations made it practically
unusable, so people used bitbanging instead. But even if there are
users, there is no platform_data or module parameter which would
need to be converted. It is just another driver doing I2C
transfers, just way better. Modifications of arch/arm/at91 related
files have proper acks from the maintainer.
- new driver for R-Car I2C
- devicetree and generic_clock conversions and fixes
- usual driver fixes and changes.
The rework patches have come a long way and lots of people have been
involved in creating/testing them. Most patches have been in
linux-next at least since 3.6-rc5. A few have been added in the last
week, I have to admit.
An unexpected (but welcome :)) peak in private life is the cause for
that. The "late" patches shouldn't cause any merge conflicts and I
will have a special eye on them during the stabilization phase. This
is an exception and I want to have the patches in place properly in
time again for the next kernels."
* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (44 commits)
MXS: Implement DMA support into mxs-i2c
i2c: add Renesas R-Car I2C driver
i2c: s3c2410: use clk_prepare_enable and clk_disable_unprepare
ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints
i2c: nomadik: Add Device Tree support to the Nomadik I2C driver
i2c: algo: pca: Fix chip reset function for PCA9665
i2c: mpc: Wait for STOP to hit the bus
i2c: davinci: preparation for switch to common clock framework
omap-i2c: fix incorrect log message when using a device tree
i2c: omap: sanitize exit path
i2c: omap: switch over to autosuspend API
i2c: omap: remove unnecessary pm_runtime_suspended check
i2c: omap: switch to threaded IRQ support
i2c: omap: remove redundant status read
i2c: omap: get rid of the "complete" label
i2c: omap: resize fifos before each message
i2c: omap: simplify IRQ exit path
i2c: omap: always return IRQ_HANDLED
i2c: omap: simplify errata check
i2c: omap: bus: add a receiver flag
...
A series of fixes (and in some cases, some cleanups):
Via Tony Lindgren:
- A collection of OMAP regression fixes, in particular because firmware
no longer sets up all pin states before starting the kernel.
- cpufreq fixes for OMAP (Rafael is on vacation and this was pre-agreed).
- A longer series of misc regression fixes and cleanups, warning removals,
etc for OMAP
From Arnd Bergmann:
- A series of warning fixes for various platforms (defconfig builds)
Misc:
- A couple of tegra fixes, one for i.MX, some vt8500 fixes, etc.
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Merge tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"A series of fixes (and in some cases, some cleanups):
Via Tony Lindgren:
- A collection of OMAP regression fixes, in particular because
firmware no longer sets up all pin states before starting the
kernel.
- cpufreq fixes for OMAP (Rafael is on vacation and this was
pre-agreed).
- A longer series of misc regression fixes and cleanups, warning
removals, etc for OMAP
From Arnd Bergmann:
- A series of warning fixes for various platforms (defconfig builds)
Misc:
- A couple of tegra fixes, one for i.MX, some vt8500 fixes, etc."
* tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (73 commits)
ARM: pxa: armcore: fix PCI PIO warnings
ARM: integrator: use __iomem pointers for MMIO, part 2
ARM: assabet: fix bogus warning in get_assabet_scr (again)
ARM: shmobile: mark shmobile_init_late as __init
ARM: integrator_cp: fix build failure
ARM: OMAP4/AM335x: hwmod: fix disable_module regression in hardreset handling
ARM: OMAP3: fix workaround for EMU clockdomain
arm/omap: Replace board_ref_clock with enum values
ARM: OMAP2+: remove duplicated include from board-omap3stalker.c
arch/arm/plat-omap/omap-pm-noop.c: Remove unecessary semicolon
arch/arm/mach-omap2: Remove unecessary semicolon
arch/arm/mach-omap1/devices.c: Remove unecessary semicolon
ARM/dts: omap5-evm: pinmux configuration for audio
ARM/dts: Add pinctrl driver entries for omap5
ARM/dts: omap4-panda: pinmux configuration for audio
ARM/dts: omap4-sdp: pinmux configuration for audio
ARM/dts: omap5-evm: Disable unused McBSP3
ARM/dts: omap4-sdp: Disable unused McBSP3
ARM/dts: omap4-panda: Disable unused audio IPs
ARM: OMAP: board-omap4panda: Pin mux configuration for audio needs
...
In autofs4_d_automount(), if a mount fail occurs the AUTOFS_INF_PENDING
mount pending flag is not cleared.
One effect of this is when using the "browse" option, directory entry
attributes show up with all "?"s due to the incorrect callback and
subsequent failure return (when in fact no callback should be made).
Signed-off-by: Ian Kent <ikent@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge misc fixes from Andrew Morton:
"Followups, fixes and some random stuff I found on the internet."
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (11 patches)
perf: fix duplicate header inclusion
memcg, kmem: fix build error when CONFIG_INET is disabled
rtc: kconfig: fix RTC_INTF defaults connected to RTC_CLASS
rapidio: fix comment
lib/kasprintf.c: use kmalloc_track_caller() to get accurate traces for kvasprintf
rapidio: update for destination ID allocation
rapidio: update asynchronous discovery initialization
rapidio: use msleep in discovery wait
mm: compaction: fix bit ranges in {get,clear,set}_pageblock_skip()
arch/powerpc/platforms/pseries/hotplug-memory.c: section removal cleanups
arch/powerpc/platforms/pseries/hotplug-memory.c: fix section handling code