linux-stable.git/Documentation, branch linux-5.7.y

x86/bugs/multihit: Fix mitigation reporting when VMX is not in use

2020-08-21T11:07:39+00:00

[ Upstream commit f29dfa53cc8ae6ad93bae619bcc0bf45cab344f7 ]

On systems that have virtualization disabled or unsupported, sysfs
mitigation for X86_BUG_ITLB_MULTIHIT is reported incorrectly as:

  $ cat /sys/devices/system/cpu/vulnerabilities/itlb_multihit
  KVM: Vulnerable

System is not vulnerable to DoS attack from a rogue guest when
virtualization is disabled or unsupported in the hardware. Change the
mitigation reporting for these cases.

Fixes: b8e8c8303ff2 ("kvm: mmu: ITLB_MULTIHIT mitigation")
Reported-by: Nelson Dsouza 
Co-developed-by: Sean Christopherson 
Signed-off-by: Sean Christopherson 
Signed-off-by: Pawan Gupta 
Signed-off-by: Ingo Molnar 
Reviewed-by: Tony Luck 
Acked-by: Thomas Gleixner 
Link: https://lore.kernel.org/r/0ba029932a816179b9d14a30db38f0f11ef1f166.1594925782.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Sasha Levin

dt-bindings: iio: io-channel-mux: Fix compatible string in example code

2020-08-21T11:07:22+00:00

commit add48ba425192c6e04ce70549129cacd01e2a09e upstream.

The correct compatible string is "gpio-mux" (see
bindings/mux/gpio-mux.txt).

Cc: stable@vger.kernel.org # v4.13+
Reviewed-by: Peter Rosin 
Signed-off-by: Christian Eggers 
Link: https://lore.kernel.org/r/20200727101605.24384-1-ceggers@arri.de
Signed-off-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: remove cede offline state for CPUs

2020-08-19T06:23:54+00:00

[ Upstream commit 48f6e7f6d948b56489da027bc3284c709b939d28 ]

This effectively reverts commit 3aa565f53c39 ("powerpc/pseries: Add
hooks to put the CPU into an appropriate offline state"), which added
an offline mode for CPUs which uses the H_CEDE hcall instead of the
architected stop-self RTAS function in order to facilitate "folding"
of dedicated mode processors on PowerVM platforms to achieve energy
savings. This has been the default offline mode since its
introduction.

There's nothing about stop-self that would prevent the hypervisor from
achieving the energy savings available via H_CEDE, so the original
premise of this change appears to be flawed.

I also have encountered the claim that the transition to and from
ceded state is much faster than stop-self/start-cpu. Certainly we
would not want to use stop-self as an *idle* mode. That is what H_CEDE
is for. However, this difference is insignificant in the context of
Linux CPU hotplug, where the latency of an offline or online operation
on current systems is on the order of 100ms, mainly attributable to
all the various subsystems' cpuhp callbacks.

The cede offline mode also prevents accurate accounting, as discussed
before:
https://lore.kernel.org/linuxppc-dev/1571740391-3251-1-git-send-email-ego@linux.vnet.ibm.com/

Unconditionally use stop-self to offline processor threads. This is
the architected method for offlining CPUs on PAPR systems.

The "cede_offline" boot parameter is rendered obsolete.

Removing this code enables the removal of the partition suspend code
which temporarily onlines all present CPUs.

Fixes: 3aa565f53c39 ("powerpc/pseries: Add hooks to put the CPU into an appropriate offline state")
Signed-off-by: Nathan Lynch
Reviewed-by: Gautham R. Shenoy
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20200612051238.1007764-2-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin

iio: improve IIO_CONCENTRATION channel type description

2020-08-19T06:23:45+00:00

[ Upstream commit df16c33a4028159d1ba8a7061c9fa950b58d1a61 ]

IIO_CONCENTRATION together with INFO_RAW specifier is used for reporting
raw concentrations of pollutants. Raw value should be meaningless
before being properly scaled. Because of that description shouldn't
mention raw value unit whatsoever.

Fix this by rephrasing existing description so it follows conventions
used throughout IIO ABI docs.

Fixes: 8ff6b3bc94930 ("iio: chemical: Add IIO_CONCENTRATION channel type")
Signed-off-by: Tomasz Duszynski 
Acked-by: Matt Ranostay 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Sasha Levin

arm64: Add KRYO4XX silver CPU cores to erratum list 1530923 and 1024718

2020-07-22T07:34:02+00:00

[ Upstream commit 9b23d95c539ebc5d6d6b5d6f20d2d7922384e76e ]

KRYO4XX silver/LITTLE CPU cores with revision r1p0 are affected by
erratum 1530923 and 1024718, so add them to the respective list.
The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., r1p0 is equivalent to rdpe.

Signed-off-by: Sai Prakash Ranjan 
Link: https://lore.kernel.org/r/7013e8a3f857ca7e82863cc9e34a614293d7f80c.1593539394.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon 
Signed-off-by: Sasha Levin

arm64: Add KRYO4XX gold CPU cores to erratum list 1463225 and 1418040

2020-07-22T07:34:02+00:00

[ Upstream commit a9e821b89daa55cc940c546b124101939d3f0451 ]

KRYO4XX gold/big CPU core revisions r0p0 to r3p1 are affected by
erratum 1463225 and 1418040, so add them to the respective list.
The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., (r0p0 to r3p1) is equivalent to (rcpe to rfpf).

Signed-off-by: Sai Prakash Ranjan 
Link: https://lore.kernel.org/r/83780e80c6377c12ca51b5d53186b61241685e49.1593539394.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon 
Signed-off-by: Sasha Levin

dt-bindings: fix error in 'make clean' after 'make dt_binding_check'

2020-07-22T07:34:00+00:00

[ Upstream commit fa714cf58c7c09a454ff9fda2ee8318591128eb6 ]

We are having more and more schema files.

Commit 8b6b80218b01 ("dt-bindings: Fix command line length limit
calling dt-mk-schema") fixed the 'Argument list too long' error of
the schema checks, but the same error happens while cleaning too.

'make clean' after 'make dt_binding_check' fails as follows:

  $ make dt_binding_check
    [ snip ]
  $ make clean
  make[2]: execvp: /bin/sh: Argument list too long
  make[2]: *** [scripts/Makefile.clean:52: __clean] Error 127
  make[1]: *** [scripts/Makefile.clean:66: Documentation/devicetree/bindings] Error 2
  make: *** [Makefile:1763: _clean_Documentation] Error 2

'make dt_binding_check' generates so many .example.dts, .dt.yaml files,
which are passed to the 'rm' command when you run 'make clean'.

I added a small hack to use the 'find' command to clean up most of the
build artifacts before they are processed by scripts/Makefile.clean

Signed-off-by: Masahiro Yamada 
Link: https://lore.kernel.org/r/20200625170434.635114-2-masahiroy@kernel.org
Signed-off-by: Rob Herring 
Signed-off-by: Sasha Levin

dt-bindings: mailbox: zynqmp_ipi: fix unit address

2020-07-22T07:34:00+00:00

[ Upstream commit 35b9c0fdb9f666628ecda02b1fc44306933a2d97 ]

Fix unit address to match the first address specified in the reg
property of the node in example.

Signed-off-by: Kangmin Park 
Link: https://lore.kernel.org/r/20200625135158.5861-1-l4stpr0gr4m@gmail.com
Signed-off-by: Rob Herring 
Signed-off-by: Sasha Levin

dt-bindings: bus: uniphier-system-bus: fix warning in example

2020-07-22T07:34:00+00:00

[ Upstream commit 0fb24d1e5a6cf3b7ca0df325fbfb10895df41bec ]

Since commit e69f5dc623f9 ("dt-bindings: serial: Convert 8250 to
json-schema"), the schema for "ns16550a" is checked.

'make dt_binding_check' emits the following warning:

  uart@5,00200000: $nodename:0: 'uart@5,00200000' does not match '^serial(@[0-9a-f,]+)*$'

Rename the node to follow the pattern defined in
Documentation/devicetree/bindings/serial/serial.yaml

While I was here, I removed leading zeros from unit names.

Signed-off-by: Masahiro Yamada 
Link: https://lore.kernel.org/r/20200623113242.779241-1-yamada.masahiro@socionext.com
Signed-off-by: Rob Herring 
Signed-off-by: Sasha Levin

dt-bindings: display: mediatek: control dpi pins mode to avoid leakage

2020-06-22T07:32:30+00:00

[ Upstream commit b0ff9b590733079f7f9453e5976a9dd2630949e3 ]

Add property "pinctrl-names" to swap pin mode between gpio and dpi mode.
Set the dpi pins to gpio mode and output-low to avoid leakage current
when dpi disabled.

Acked-by: Rob Herring 
Signed-off-by: Jitao Shi 
Signed-off-by: Chun-Kuang Hu 
Signed-off-by: Sasha Levin