* Use the buffer content length as opposed to the total buffer size. This can
be a real problem when using the mos7840 as a usb serial-console as all
kernel output is truncated during boot.
Signed-off-by: Mark Ferrell <mferrell@uplogix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In this patch, we add new declarations into option.c to support the new
interfaces of Huawei Data Card devices. And at the same time, remove the
redundant declarations from option.c.
A lot of Broadcom Bluetooth devices provides vendor specific interface
class and we are getting flooded by patches adding new device support.
This change will help us enable support for any other Broadcom with vendor
specific device that arrives in the future.
Only the product id changes for those devices, so this macro would be
perfect for us:
Commit 3902a370281d2f2b130f141e8cf94eab40125769 (staging: comedi:
refactor comedi_device_attach() a bit) by yours truly introduced an
inverted logic bug in comedi_device_attach() for the case where the
driver expects the device to be configured by driver name rather than
board name. The result of a strcmp() is being tested incorrectly. Fix
it.
Thanks to Stephen N Chivers for discovering the bug and suggesting the
fix.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c4e00daaa96d3a0786f1f4fe6456281c60ef9a16 changed __dev_printk
in a way that broke dynamic-debug's ability to control the dynamic
prefix of dev_dbg(dev,..), but not dev_dbg(NULL,..) or pr_debug(..),
which is why it wasnt noticed sooner.
When dev==NULL, __dev_printk() just calls printk(), which just works.
But otherwise, it assumed that level was always a string like "<L>"
and just plucked out the 'L', ignoring the rest. However,
dynamic_emit_prefix() adds "[tid] module:func:line:" to the string,
those additions all got lost.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Acked-by: Jason Baron <jbaron@redhat.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes a particularly nasty bug that was revealed by the ring
expansion patches. The bug has been present since the very beginning of
the xHCI driver history, and could have caused general protection faults
from bad memory accesses.
The first thing to note is that a Set TR Dequeue Pointer command can
move the dequeue pointer to a link TRB, if the canceled or stalled
transfer TD ended just before a link TRB. The function to increment the
dequeue pointer, inc_deq, was written before cancellation and stall
support was added. It assumed that the dequeue pointer could never
point to a link TRB. It would unconditionally increment the dequeue
pointer at the start of the function, check if the pointer was now on a
link TRB, and move it to the top of the next segment if so.
This means that if a Set TR Dequeue Point command moved the dequeue
pointer to a link TRB, a subsequent call to inc_deq() would move the
pointer off the segment and into la-la-land. It would then read from
that memory to determine if it was a link TRB. Other functions would
often call inc_deq() until the dequeue pointer matched some other
pointer, which means this function would quite happily read all of
system memory before wrapping around to the right pointer value.
Often, there would be another endpoint segment from a different ring
allocated from the same DMA pool, which would be contiguous to the
segment inc_deq just stepped off of. inc_deq would eventually find the
link TRB in that segment, and blindly move the dequeue pointer back to
the top of the correct ring segment.
The only reason the original code worked at all is because there was
only one ring segment. With the ring expansion patches, the dequeue
pointer would eventually wrap into place, but the dequeue segment would
be out-of-sync. On the second TD after the dequeue pointer was moved to
a link TRB, trb_in_td() would fail (because the dequeue pointer and
dequeue segment were out-of-sync), and this message would appear:
ERROR Transfer event TRB DMA ptr not part of current TD
This fixes bugzilla entry 4333 (option-based modem unhappy on USB 3.0
port: "Transfer event TRB DMA ptr not part of current TD", "rejecting
I/O to offline device"),
https://bugzilla.kernel.org/show_bug.cgi?id=43333
and possibly other general protection fault bugs as well.
This patch should be backported to kernels as old as 2.6.31. A separate
patch will be created for kernels older than 3.4, since inc_deq was
modified in 3.4 and this patch will not apply.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Tested-by: James Ettle <theholyettlz@googlemail.com> Tested-by: Matthew Hall <mhall@mhcomputing.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Intel desktop boards DH77EB and DH77DF have a hardware issue that
can be worked around by BIOS. If the USB ports are switched to xHCI on
shutdown, the xHCI host will send a spurious interrupt, which will wake
the system. Some BIOS will work around this, but not all.
The bug can be avoided if the USB ports are switched back to EHCI on
shutdown. The Intel Windows driver switches the ports back to EHCI, so
change the Linux xHCI driver to do the same.
Unfortunately, we can't tell the two effected boards apart from other
working motherboards, because the vendors will change the DMI strings
for the DH77EB and DH77DF boards to their own custom names. One example
is Compulab's mini-desktop, the Intense-PC. Instead, key off the
Panther Point xHCI host PCI vendor and device ID, and switch the ports
over for all PPT xHCI hosts.
The only impact this will have on non-effected boards is to add a couple
hundred milliseconds delay on boot when the BIOS has to switch the ports
over from EHCI to xHCI.
This patch should be backported to kernels as old as 3.0, that contain
the commit 69e848c2090aebba5698a1620604c7dccb448684 "Intel xhci: Support
EHCI/xHCI port switching."
The NEC/Renesas 720201 xHCI host controller does not complete its reset
within 250 milliseconds. In fact, it takes about 9 seconds to reset the
host controller, and 1 second for the host to be ready for doorbell
rings. Extend the reset and CNR polling timeout to 10 seconds each.
This patch should be backported to kernels as old as 2.6.31, that
contain the commit 66d4eadd8d067269ea8fead1a50fe87c2979a80d "USB: xhci:
BIOS handoff and HW initialization."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Reported-by: Edwin Klein Mentink <e.kleinmentink@zonnet.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Gary reports that with recent kernels, he notices more xHCI driver
warnings:
xhci_hcd 0000:03:00.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
We think his Etron xHCI host controller may have the same buggy behavior
as the Fresco Logic xHCI host. When a short transfer is received, the
host will mark the transfer as successfully completed when it should be
marking it with a short completion.
Fix this by turning on the XHCI_TRUST_TX_LENGTH quirk when the Etron
host is discovered. Note that Gary has revision 1, but if Etron fixes
this bug in future revisions, the quirk will have no effect.
This patch should be backported to kernels as old as 2.6.36, that
contain a backported version of commit 1530bbc6272d9da1e39ef8e06190d42c13a02733 "xhci: Add new short TX quirk
for Fresco Logic host."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Reported-by: Gary E. Miller <gem@rellim.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 968dee7722: "ext4: fix hole punch failure when depth is greater
than 0" introduced a regression in v3.5.1/v3.6-rc1 which caused kernel
crashes when users ran run "rm -rf" on large directory hierarchy on
ext4 filesystems on RAID devices:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
The problem in commit 968dee7722 was that caused the variable 'i' to
be left uninitialized if the truncate required more space than was
available in the journal. This resulted in the function
ext4_ext_truncate_extend_restart() returning -EAGAIN, which caused
ext4_ext_remove_space() to restart the truncate operation after
starting a new jbd2 handle.
Commit 8aeb00ff85a: "ext4: fix overhead calculation used by
ext4_statfs()" introduced a O(n**2) calculation which makes very large
file systems take forever to mount. Fix this with an optimization for
non-bigalloc file systems. (For bigalloc file systems the overhead
needs to be set in the the superblock.)
While in ext4_validate_block_bitmap(), if an block allocation bitmap
is found to be invalid, we call ext4_error() while the block group is
still locked. This causes ext4_commit_super() to call a function
which might sleep while in an atomic context.
There's no need to keep the block group locked at this point, so hoist
the ext4_error() call up to ext4_validate_block_bitmap() and release
the block group spinlock before calling ext4_error().
Commit 03179fe923 introduced a kmemcheck complaint in
ext4_da_get_block_prep() because we save and restore
ei->i_da_metadata_calc_last_lblock even though it is left
uninitialized in the case where i_da_metadata_calc_len is zero.
This doesn't hurt anything, but silencing the kmemcheck complaint
makes it easier for people to find real bugs.
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=45631
(which is marked as a regression).
After we transfer set the EXT4_ERROR_FS bit in the file system
superblock, it's not enough to call jbd2_journal_clear_err() to clear
the error indication from journal superblock --- we need to call
jbd2_journal_update_sb_errno() as well. Otherwise, when the root file
system is mounted read-only, the journal is replayed, and the error
indicator is transferred to the superblock --- but the s_errno field
in the jbd2 superblock is left set (since although we cleared it in
memory, we never flushed it out to disk).
This can end up confusing e2fsck. We should make e2fsck more robust
in this case, but the kernel shouldn't be leaving things in this
confused state, either.
The core ptrace access checking routine holds a task lock, and when
reporting a failure, Yama takes a separate task lock. To avoid a
potential deadlock with two ptracers taking the opposite locks, do not
use get_task_comm() and just use ->comm directly since accuracy is not
important for the report.
The sixteen bank case wasn't handled here, leading to GPU
crashes because of userspace miscalculation.
Signed-off-by: Christian König <deathsimple@vodafone.de> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 0136db586c028f71e7cc21cc183064ff0d5919c8 merges rc6 information
into the power group. However, when compiled with CONFIG_PM not set,
modprobing i915 would taint since power_group_name is defined as NULL.
This patch makes these rc6 in sysfs functions conditional upon the
definition of the CONFIG_PM macro to avoid the above-mentioned problem.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45181 Tested-by: Kris Karas <bugs-a12@moonlit-rail.com> Signed-off-by: Hunt Xu <mhuntxu@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It seems we can not update the crtc scanout address. After disabling
crtc, update to base address do not take effect after crtc being
reenable leading to at least frame being scanout from the old crtc
base address. Disabling crtc display request lead to same behavior.
So after changing the vram address if we don't keep crtc disabled
we will have the GPU trying to read some random system memory address
with some iommu this will broke the crtc engine and will lead to
broken display and iommu error message.
So to avoid this, disable crtc. For flicker less boot we will need
to avoid moving the vram start address.
Need to make sure the crtc is gated on before modesetting.
Explicitly gate the crtc on in prepare() and set a flag
so that the dpms functions don't gate it off during
mode set.
Noticed by sylware on IRC.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/i915: enable vdd when switching off the eDP panel
But that patch also tried to fix some neat edp sequence issue with the
force_vdd timings. Closer inspection reveals that we've raised
force_vdd only to do the aux channel communication dp_sink_dpms. If we
move the edp_panel_off below that, we don't need any force_vdd for the
disable sequence, which makes the Air happy.
Unfortunately the reporter of the original bug that the above commit
fixed is travelling, so we can't test whether this regresses things.
But my theory is that since we don't check for any power-off ->
force_vdd-on delays in edp_panel_vdd_on, this was the actual
root-cause of this failure. With that force_vdd dance completely
eliminated, I'm hopeful the original bug stays fixed, too.
For reference the old bug, which hopefully doesn't get broken by this:
https://bugzilla.kernel.org/show_bug.cgi?id=43163
In any case, regression fixers win over plain bugfixes, so this needs
to go in asap.
v2: The crucial pieces seems to be to clear the force_vdd flag
uncoditionally, too, in edp_panel_off. Looks like this is left behind
by the firmware somehow.
v3: The Apple firmware seems to switch off the panel on it's own, hence
we still need to keep force_vdd on, but properly clear it when switching
the panel off.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45671 Tested-by: Roberto Romer <sildurin@gmail.com> Tested-by: Daniel Wagner <wagi@monom.org> Tested-by: Keith Packard <keithp@keithp.com> Cc: Keith Packard <keithp@keithp.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We may only start to set up the new register values after having
confirmed that the ring is truely off. Otherwise the hw might lose the
newly written register values. This is caught later on in the init
sequence, when we check whether the register writes have stuck.
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50522 Tested-by: Yang Guang <guang.a.yang@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
High frequency link configurations have the potential to cause trouble
with long and/or cheap cables, so prefer slow and wide configurations
instead. This patch has the potential to cause trouble for eDP
configurations that lie about available lanes, so if we run into that we
can make it conditional on eDP.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45801 Tested-by: peter@colberg.org Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We then try to populate those pages back. In the P2M tree however
the space for those leafs must be reserved - as such we use extend_brk.
We reserve 8MB of _brk space, which means we can fit over 1048576 PFNs - which is more than we should ever need.
Without this, on certain compilation of the kernel we would hit:
Interestingly enough, most of the time we are not going to hit this
b/c the _brk space is quite large (v3.5): ffffffff81a25000 B __brk_base ffffffff81e43000 B __brk_limit
= ~4MB.
vs earlier kernels (with this back-ported), the space is smaller: ffffffff81a25000 B __brk_base ffffffff81a7b000 B __brk_limit
= 344 kBytes.
where we would certainly hit this and hit extend_brk.
Commit 7572777eef78ebdee1ecb7c258c0ef94d35bad16 attempted to verify that
the total iovec from the client doesn't overflow iov_length() but it
only checked the first element. The iovec could still overflow by
starting with a small element. The obvious fix is to check all the
elements.
The overflow case doesn't look dangerous to the kernel as the copy is
limited by the length after the overflow. This fix restores the
intention of returning an error instead of successfully copying less
than the iovec represented.
I found this by code inspection. I built it but don't have a test case.
I'm cc:ing stable because the initial commit did as well.
The native 31 bit and the compat behaviour for the mmap system calls differ:
In native 31 bit mode the passed in address for the mmap system call will be
unmodified passed to sys_mmap_pgoff().
In compat mode however the passed in address will be modified with
compat_ptr() which masks out the most significant bit.
The result is that in native 31 bit mode each mmap request (with MAP_FIXED)
will fail where the most significat bit is set, while in compat mode it
may succeed.
This odd behaviour was introduced with d3815898 "[S390] mmap: add missing
compat_ptr conversion to both mmap compat syscalls".
To restore a consistent behaviour accross native and compat mode this
patch functionally reverts the above mentioned commit.
Bamboo One's with ID of 0x6a and 0x6b were added with correct
indication of 1024 pressure levels but the Graphire packet routine
was only looking at 9 bits. Increased to 10 bits.
This bug caused these devices to roll over to zero pressure at half
way mark.
The other devices using this routine only support 256 or 512 range
and look to fix unused bits at zero.
The EETI touchscreen asserts its IRQ line as soon as it has data in its
internal buffers. The line is automatically deasserted once all data has
been read via I2C. Hence, the driver has to monitor the GPIO line and
cannot simply rely on the interrupt handler reception.
In the current implementation of the driver, irq_to_gpio() is used to
determine the GPIO number from the i2c_client's IRQ value.
As irq_to_gpio() is not available on all platforms, this patch changes
this and makes the driver ignore the passed in IRQ. Instead, a GPIO is
added to the platform_data struct and gpio_to_irq is used to derive the
IRQ from that GPIO. If this fails, bail out. The driver is only able to
work in environments where the touchscreen GPIO can be mapped to an
IRQ.
Without this patch, building raumfeld_defconfig results in:
drivers/input/touchscreen/eeti_ts.c: In function 'eeti_ts_irq_active':
drivers/input/touchscreen/eeti_ts.c:65:2: error: implicit declaration of function 'irq_to_gpio' [-Werror=implicit-function-declaration]
Found that commit d478eb44 was a bad commit.
If the link partner is transmitting codeword (even if NULL codeword),
then the RXCW.C bit will be set so check for RXCW.CW is unnecessary.
Ref: RH BZ 840642
Reported-by: Fabio Futigami <ffutigam@redhat.com> Signed-off-by: Tushar Dave <tushar.n.dave@intel.com> CC: Marcelo Ricardo Leitner <mleitner@redhat.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's a bug that causes the rate scaling to get stuck
when it has to use single-stream rates with a peer that
can do GF and SGI; the two are incompatible so we can't
use them together, but that causes the algorithm to not
work at all, it always rejects updates.
Disable greenfield for now to prevent that problem.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Tested-by: Cesar Eduardo Barros <cesarb@cesarb.net> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The higher ptrace restriction levels should be blocking even
PTRACE_TRACEME requests. The comments in the LSM documentation are
misleading about when the checks happen (the parent does not go through
security_ptrace_access_check() on a PTRACE_TRACEME call).
This is a fix for bug, introduced in 3.4 kernel by commit 1ab5ecb90cb6a3df1476e052f76a6e8f6511cb3d ("tun: don't hold network
namespace by tun sockets"), which, among other things, replaced simple
sock_put() by sk_release_kernel(). Below is sequence, which leads to
oops for non-persistent devices:
While tracking down a weird buffer overflow issue in a program that
looked to be sane, I started double checking the length returned by
syslog(SYSLOG_ACTION_READ_ALL, ...) to make sure it wasn't overflowing
the buffer.
It turns out that the loops that calculate how much space the entries
will take when they're copied don't include the newlines and prefixes
that will be included in the final output since prev flags is passed as
zero.
This patch properly accounts for it and fixes the overflow.
libertas currently calls cfg80211_disconnected() when it is being
brought down. This causes an event to be allocated, but since the
wdev is already removed from the rdev by the time that the event
processing work executes, the event is never processed or freed.
http://article.gmane.org/gmane.linux.kernel.wireless.general/95666
Fix this leak, and other possible situations, by processing the event
queue when a device is being unregistered. Thanks to Johannes Berg for
the suggestion.
Signed-off-by: Daniel Drake <dsd@laptop.org> 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>
The irq_to_gpio function was removed from the pxa platform
in linux-3.2, and this driver has been broken since.
There is actually no in-tree user of this driver that adds
this platform device, but the driver can and does get enabled
on some platforms.
Without this patch, building ezx_defconfig results in:
drivers/mfd/ezx-pcap.c: In function 'pcap_isr_work':
drivers/mfd/ezx-pcap.c:205:2: error: implicit declaration of function 'irq_to_gpio' [-Werror=implicit-function-declaration]
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Daniel Ribeiro <drwyrm@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit c7e963f (net/smsc911x: Add regulator support), the lan9220
device tree probe fails on imx53-ard board, because the commit makes
VDD33A and VDDVARIO supplies mandatory for the driver.
Add a fixed dummy 3V3 supplying lan9220 to fix the regression.
The CONFIG_DEFAULT_MMAP_MIN_ADDR was set to 65536 in mxs_defconfig,
this caused severe breakage of userland applications since the upper
limit for ARM is 32768. By default CONFIG_DEFAULT_MMAP_MIN_ADDR is
set to 4096 and can also be changed via /proc/sys/vm/mmap_min_addr
if needed.
Quoting Russell King [1]:
"4096 is also fine for ARM too. There's not much point in having
defconfigs change it - that would just be pure noise in the config
files."
the CONFIG_DEFAULT_MMAP_MIN_ADDR can be removed from the defconfig
altogether.
This problem was introduced by commit cde7c41 (ARM: configs: add
defconfig for mach-mxs).
Signed-off-by: Marek Vasut <marex@denx.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Wolfgang Denk <wd@denx.de> Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The imx5 common clock migration causes a regression with smsc911x
driver on imx53-ard board, where a smsc lan9220 controller gets
connected on imx53 with EIM interface. EIM needs clock emi_slow_gate
to be functional. In the new imx5 clock driver, there is no use count
incremented for the clock by enabling it, so the framework closes the
clock at late init time and makes EIM stop working then.
Enable emi_slow_gate in clock driver initialization to fix the
regression.
It's possible for an initiator to send us an UNMAP command with a
descriptor that is less than 8 bytes; in that case it's really bad for
us to set an unsigned int to that value, subtract 8 from it, and then
use that as a limit for our loop (since the value will wrap around to
a huge positive value).
Fix this by making size be signed and only looping if size >= 16 (ie
if we have at least a full descriptor available).
Also remove offset as an obfuscated name for the constant 8.
Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
[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>
The UNMAP DATA LENGTH and UNMAP BLOCK DESCRIPTOR DATA LENGTH fields
are in the unmap descriptor (the payload transferred to our data out
buffer), not in the CDB itself. Read them from the correct place in
target_emulated_unmap.
Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
[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>
When processing an UNMAP command, we need to make sure that the number
of blocks we're asked to UNMAP does not exceed our reported maximum
number of blocks per UNMAP, and that the range of blocks we're
unmapping doesn't go past the end of the device.
Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
[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>
If a process creates a large hugetlbfs mapping that is eligible for page
table sharing and forks heavily with children some of whom fault and
others which destroy the mapping then it is possible for page tables to
get corrupted. Some teardowns of the mapping encounter a "bad pmd" and
output a message to the kernel log. The final teardown will trigger a
BUG_ON in mm/filemap.c.
This was reproduced in 3.4 but is known to have existed for a long time
and goes back at least as far as 2.6.37. It was probably was introduced
in 2.6.20 by [39dde65c: shared page table for hugetlb page]. The messages
look like this;
The bug is a race and not always easy to reproduce. To reproduce it I was
doing the following on a single socket I7-based machine with 16G of RAM.
$ hugeadm --pool-pages-max DEFAULT:13G
$ echo $((18*1048576*1024)) > /proc/sys/kernel/shmmax
$ echo $((18*1048576*1024)) > /proc/sys/kernel/shmall
$ for i in `seq 1 9000`; do ./hugetlbfs-test; done
On my particular machine, it usually triggers within 10 minutes but
enabling debug options can change the timing such that it never hits.
Once the bug is triggered, the machine is in trouble and needs to be
rebooted. The machine will respond but processes accessing proc like "ps
aux" will hang due to the BUG_ON. shutdown will also hang and needs a
hard reset or a sysrq-b.
The basic problem is a race between page table sharing and teardown. For
the most part page table sharing depends on i_mmap_mutex. In some cases,
it is also taking the mm->page_table_lock for the PTE updates but with
shared page tables, it is the i_mmap_mutex that is more important.
Unfortunately it appears to be also insufficient. Consider the following
situation
In this scenario, it is possible for Process A to share page tables with
Process B that is trying to tear them down. The i_mmap_mutex on its own
does not prevent Process A walking Process B's page tables. At (1) above,
the page tables are not shared yet so it unmaps the PMDs. Process A sets
up page table sharing and at (2) faults a new entry. Process B then trips
up on it in free_pgtables.
This patch fixes the problem by adding a new function
__unmap_hugepage_range_final that is only called when the VMA is about to
be destroyed. This function clears VM_MAYSHARE during
unmap_hugepage_range() under the i_mmap_mutex. This makes the VMA
ineligible for sharing and avoids the race. Superficially this looks like
it would then be vunerable to truncate and madvise issues but hugetlbfs
has its own truncate handlers so does not use unmap_mapping_range() and
does not support madvise(DONTNEED).
This should be treated as a -stable candidate if it is merged.
Test program is as follows. The test case was mostly written by Michal
Hocko with a few minor changes to reproduce this bug.
Mix in any architectural randomness in extract_buf() instead of
xfer_secondary_buf(). This allows us to mix in more architectural
randomness, and it also makes xfer_secondary_buf() faster, moving a
tiny bit of additional CPU overhead to process which is extracting the
randomness.
[ Commit description modified by tytso to remove an extended
advertisement for the RDRAND instruction. ]
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: DJ Johnston <dj.johnston@intel.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many platforms have per-machine instance data (serial numbers,
asset tags, etc.) squirreled away in areas that are accessed
during early system bringup. Mixing this data into the random
pools has a very high value in providing better random data,
so we should allow (and even encourage) architecture code to
call add_device_randomness() from the setup_arch() paths.
However, this limits our options for internal structure of
the random driver since random_initialize() is not called
until long after setup_arch().
Add a big fat comment to rand_initialize() spelling out
this requirement.
With the new interrupt sampling system, we are no longer using the
timer_rand_state structure in the irq descriptor, so we can stop
initializing it now.
[ Merged in fixes from Sedat to find some last missing references to
rand_initialize_irq() ]
The tamper evident features of the RTC include the "write counter" which
is a pseudo-random number regenerated whenever we set the RTC. Since this
value is unpredictable it should provide some useful seeding to the random
number generator.
Only do this on boot since the goal is to seed the pool rather than add
useful entropy.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Create a new function, get_random_bytes_arch() which will use the
architecture-specific hardware random number generator if it is
present. Change get_random_bytes() to not use the HW RNG, even if it
is avaiable.
The reason for this is that the hw random number generator is fast (if
it is present), but it requires that we trust the hardware
manufacturer to have not put in a back door. (For example, an
increasing counter encrypted by an AES key known to the NSA.)
It's unlikely that Intel (for example) was paid off by the US
Government to do this, but it's impossible for them to prove otherwise
--- especially since Bull Mountain is documented to use AES as a
whitener. Hence, the output of an evil, trojan-horse version of
RDRAND is statistically indistinguishable from an RDRAND implemented
to the specifications claimed by Intel. Short of using a tunnelling
electronic microscope to reverse engineer an Ivy Bridge chip and
disassembling and analyzing the CPU microcode, there's no way for us
to tell for sure.
Since users of get_random_bytes() in the Linux kernel need to be able
to support hardware systems where the HW RNG is not present, most
time-sensitive users of this interface have already created their own
cryptographic RNG interface which uses get_random_bytes() as a seed.
So it's much better to use the HW RNG to improve the existing random
number generator, by mixing in any entropy returned by the HW RNG into
/dev/random's entropy pool, but to always _use_ /dev/random's entropy
pool.
This way we get almost of the benefits of the HW RNG without any
potential liabilities. The only benefits we forgo is the
speed/performance enhancements --- and generic kernel code can't
depend on depend on get_random_bytes() having the speed of a HW RNG
anyway.
For those places that really want access to the arch-specific HW RNG,
if it is available, we provide get_random_bytes_arch().
If the CPU supports a hardware random number generator, use it in
xfer_secondary_pool(), where it will significantly improve things and
where we can afford it.
Also, remove the use of the arch-specific rng in
add_timer_randomness(), since the call is significantly slower than
get_cycles(), and we're much better off using it in
xfer_secondary_pool() anyway.
Add a new interface, add_device_randomness() for adding data to the
random pool that is likely to differ between two devices (or possibly
even per boot). This would be things like MAC addresses or serial
numbers, or the read-out of the RTC. This does *not* add any actual
entropy to the pool, but it initializes the pool to different values
for devices that might otherwise be identical and have very little
entropy available to them (particularly common in the embedded world).
[ Modified by tytso to mix in a timestamp, since there may be some
variability caused by the time needed to detect/configure the hardware
in question. ]
The real-time Linux folks don't like add_interrupt_randomness() taking
a spinlock since it is called in the low-level interrupt routine.
This also allows us to reduce the overhead in the fast path, for the
random driver, which is the interrupt collection path.
We've been moving away from add_interrupt_randomness() for various
reasons: it's too expensive to do on every interrupt, and flooding the
CPU with interrupts could theoretically cause bogus floods of entropy
from a somewhat externally controllable source.
This solves both problems by limiting the actual randomness addition
to just once a second or after 64 interrupts, whicever comes first.
During that time, the interrupt cycle data is buffered up in a per-cpu
pool. Also, we make sure the the nonblocking pool used by urandom is
initialized before we start feeding the normal input pool. This
assures that /dev/urandom is returning unpredictable data as soon as
possible.
(Based on an original patch by Linus, but significantly modified by
tytso.)
Tested-by: Eric Wustrow <ewust@umich.edu> Reported-by: Eric Wustrow <ewust@umich.edu> Reported-by: Nadia Heninger <nadiah@cs.ucsd.edu> Reported-by: Zakir Durumeric <zakir@umich.edu> Reported-by: J. Alex Halderman <jhalderm@umich.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The touchpad on the Acer Aspire One D250 will report out of range values
in the extreme lower portion of the touchpad. These appear as abrupt
changes in the values reported by the hardware from very low values to
very high values, which can cause unexpected vertical jumps in the
position of the mouse pointer.
What seems to be happening is that the value is wrapping to a two's
compliment negative value of higher resolution than the 13-bit value
reported by the hardware, with the high-order bits being truncated. This
patch adds handling for these values by converting them to the
appropriate negative values.
The only tricky part about this is deciding when to treat a number as
negative. It stands to reason that if out of range values can be
reported on the low end then it could also happen on the high end, so
not all out of range values should be treated as negative. The approach
taken here is to split the difference between the maximum legitimate
value for the axis and the maximum possible value that the hardware can
report, treating values greater than this number as negative and all
other values as positive. This can be tweaked later if hardware is found
that operates outside of these parameters.
The Intel case falls through into the generic case which then changes
the values. For cases like the P6 it doesn't do the right thing so
this seems to be a screwup.
wireless: Save original maximum regulatory transmission power for the calucation of the local maximum transmit pow
changed the way we calculate chan->max_power as min(chan->max_power,
chan->max_reg_power). That broke rt2x00 (and perhaps some other
drivers) that do not set chan->max_power. It is not so easy to fix this
problem correctly in rt2x00.
According to commit eccc068e8 changelog, change claim only to save
maximum regulatory power - changing setting of chan->max_power was side
effect. This patch restore previous calculations of chan->max_power and
do not touch chan->max_reg_power.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
AR1111 is same as AR9485. The h/w
difference between them is quite insignificant,
Felix suggests only very few baseband features
may not be available in AR1111. The h/w code for
AR9485 is already present, so AR1111 should
work fine with the addition of its PID/VID.
Reported-by: Tim Bentley <Tim.Bentley@Gmail.com> Cc: Felix Bitterli <felixb@qca.qualcomm.com> Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Tested-by: Tim Bentley <Tim.Bentley@Gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a fixed TEI is used, the initial state of the layer 2 statmachine need to be
4 (TEI assigned). This was true only for Point to Point connections, but not
for the other fixed TEIs. It was not found before, because usually only the
TEI 0 is used as fixed TEI for PtP mode, but if you try X31 packet mode
connections with SAPI 16, TEI 1, it did fail.
Signed-off-by: Karsten Keil <keil@b1-systems.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit 99b725084 "ACPI processor hotplug: Delay acpi_processor_start()
call for hotplugged cores", acpi_processor_hotplug(pr) was wrongly replaced
by acpi_processor_cst_has_changed() inside the acpi_cpu_soft_notify(). This
patch will restore it back, fixing the tick_broadcast_mask regression:
https://lkml.org/lkml/2012/7/30/169
Signed-off-by: Feng Tang <feng.tang@intel.com> Cc: Thomas Renninger <trenn@suse.de> Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Presently the oops code looks for the pgd either from the mm context or
the cached TTB value. There are presently cases where the TTB can be
unset or otherwise cleared by hardware, which we weren't handling,
resulting in recursive faults on the NULL pgd. In these cases we can
simply reload from swapper_pg_dir and continue on as normal.
Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reproducing is easy, I can hit it on a KVM system with a very basic
config (x86_64 make defconfig + enable the drivers needed). To hit it,
just install dump (on debian/ubuntu, not sure what the package might be
called on Fedora), and:
dump -o -f /tmp/foo /
You'll see the warning in dmesg once it forks off the I/O process and
starts dumping filesystem contents.
Currently ioc->nr_tasks is used to decide two things - whether an ioc
is done issuing IOs and whether it's shared by multiple tasks. This
patch separate out the first into ioc->active_ref, which is acquired
and released using {get|put}_io_context_active() respectively.
This will be used to associate bio's with a given task. This patch
doesn't introduce any visible behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
It seems like the init of ioc->nr_tasks was removed in that patch,
so it starts out at 0 instead of 1.
Tejun, is the right thing here to add back the init, or should something else
be done?
The below patch removes the warning, but I haven't done any more extensive
testing on it.
Line 0 and 1 were both written to line 0 (on the display) and all subsequent
lines had an offset of -1. The result was that the last line on the display
was never overwritten by writes to /dev/fbN.
If a resync of a RAID1 array with 2 devices finds a known bad block
one device it will neither read from, or write to, that device for
this block offset.
So there will be one read_target (The other device) and zero write
targets.
This condition causes md/raid1 to abort the resync assuming that it
has finished - without known bad blocks this would be true.
When there are no write targets because of the presence of bad blocks
we should only skip over the area covered by the bad block.
RAID10 already gets this right, raid1 doesn't. Or didn't.
As this can cause a 'sync' to abort early and appear to have succeeded
it could lead to some data corruption, so it suitable for -stable.
mmu_notifier_release() is called when the process is exiting. It will
delete all the mmu notifiers. But at this time the page belonging to the
process is still present in page tables and is present on the LRU list, so
this race will happen:
CPU 0 CPU 1
mmu_notifier_release: try_to_unmap:
hlist_del_init_rcu(&mn->hlist);
ptep_clear_flush_notify:
mmu nofifler not found
free page !!!!!!
/*
* At the point, the page has been
* freed, but it is still mapped in
* the secondary MMU.
*/
mn->ops->release(mn, mm);
Then the box is not stable and sometimes we can get this bug:
[ 738.075923] BUG: Bad page state in process migrate-perf pfn:03bec
[ 738.075931] page:ffffea00000efb00 count:0 mapcount:0 mapping: (null) index:0x8076
[ 738.075936] page flags: 0x20000000000014(referenced|dirty)
The same issue is present in mmu_notifier_unregister().
We can call ->release before deleting the notifier to ensure the page has
been unmapped from the secondary MMU before it is freed.
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.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>
On architectures with CONFIG_HUGETLB_PAGE_SIZE_VARIABLE set, such as
Itanium, pageblock_order is a variable with default value of 0. It's set
to the right value by set_pageblock_order() in function
free_area_init_core().
But pageblock_order may be used by sparse_init() before free_area_init_core()
is called along path:
sparse_init()
->sparse_early_usemaps_alloc_node()
->usemap_size()
->SECTION_BLOCKFLAGS_BITS
->((1UL << (PFN_SECTION_SHIFT - pageblock_order)) *
NR_PAGEBLOCK_BITS)
The uninitialized pageblock_size will cause memory wasting because
usemap_size() returns a much bigger value then it's really needed.
For example, on an Itanium platform,
sparse_init() pageblock_order=0 usemap_size=24576
free_area_init_core() before pageblock_order=0, usemap_size=24576
free_area_init_core() after pageblock_order=12, usemap_size=8
That means 24K memory has been wasted for each section, so fix it by calling
set_pageblock_order() from sparse_init().
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Jiang Liu <liuj97@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.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>
While trying to get a v3.5 kernel booted on the cubox, I noticed that
VFP does not work correctly with VFP bounce handling. This is because
of the confusion over 16-bit vs 32-bit instructions, and where PC is
supposed to point to.
The rule is that FP handlers are entered with regs->ARM_pc pointing at
the _next_ instruction to be executed. However, if the exception is
not handled, regs->ARM_pc points at the faulting instruction.
This is easy for ARM mode, because we know that the next instruction and
previous instructions are separated by four bytes. This is not true of
Thumb2 though.
Since all FP instructions are 32-bit in Thumb2, it makes things easy.
We just need to select the appropriate adjustment. Do this by moving
the adjustment out of do_undefinstr() into the assembly code, as only
the assembly code knows whether it's dealing with a 32-bit or 16-bit
instruction.
Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Newer OMAP CPU's are SMP machines so omap2plus_defconfig sets
CONFIG_SMP=y. Unfortunately on an OMAP UP machine is_smp()
returns false and smp_init_cpus() is never called and the
smp_cross_call() function remains NULL.
If the machine is rebooted or powered off, smp_send_stop() will
be called (since CONFIG_SMP=y) leading to the following error:
Add a check so smp_cross_call() is only called when there is more than one CPU on-line.
Signed-off-by: Javier Martinez Canillas <javier at dowhile0.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vivt_flush_cache_{range,page} functions check that the mm_struct
of the VMA being flushed has been active on the current CPU before
performing the cache maintenance.
The gate_vma has a NULL mm_struct pointer and, as such, will cause a
kernel fault if we try to flush it with the above operations. This
happens during ELF core dumps, which include the gate_vma as it may be
useful for debugging purposes.
This patch adds checks to the VIVT cache flushing functions so that VMAs
with a NULL mm_struct are flushed unconditionally (the vectors page may
be dirty if we use it to store the current TLS pointer).
Reported-by: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org> Tested-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit cdf357f1 ("ARM: 6299/1: errata: TLBIASIDIS and TLBIMVAIS
operations can broadcast a faulty ASID") replaced by-ASID TLB flushing
operations with all-ASID variants to workaround A9 erratum #720789.
This patch extends the workaround to include the tlb_range operations,
which were overlooked by the original patch.
Tested-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vfp_pm_suspend should save the VFP state in suspend after
any lazy context switch. If it only saves when the VFP is enabled,
the state can get lost when, on a UP system:
Thread 1 uses the VFP
Context switch occurs to thread 2, VFP is disabled but the
VFP context is not saved
Thread 2 initiates suspend
vfp_pm_suspend is called with the VFP disabled, and the unsaved
VFP context of Thread 1 in the registers
Modify vfp_pm_suspend to save the VFP context whenever
vfp_current_hw_state is not NULL.
Includes a fix from Ido Yariv <ido@wizery.com>, who pointed out that on
SMP systems, the state pointer can be pointing to a freed task struct if
a task exited on another cpu, fixed by using #ifndef CONFIG_SMP in the
new if clause.
Signed-off-by: Colin Cross <ccross@android.com> Cc: Barry Song <bs14@csr.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ido Yariv <ido@wizery.com> Cc: Daniel Drake <dsd@laptop.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vfp_pm_suspend runs on each cpu, only clear the hardware state
pointer for the current cpu. Prevents a possible crash if one
cpu clears the hw state pointer when another cpu has already
checked if it is valid.
Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / karo-tx-linux.git / log