Documentation: Add section about CPU vulnerabilities for Spectre

Add documentation for Spectre vulnerability and the mitigation mechanisms:

- Explain the problem and risks
- Document the mitigation

Documentation: Add section about CPU vulnerabilities for Spectre

Add documentation for Spectre vulnerability and the mitigation mechanisms:

- Explain the problem and risks
- Document the mitigation mechanisms
- Document the command line controls
- Document the sysfs files

Co-developed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Co-developed-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

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Merge tag 'v5.1' into next

Sync up with mainline to bring in the latest APIs.

Merge tag 'v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into mlx5-next

Linux 5.1-rc1

We forgot to reset the branch last merge window thus mlx5-next is outdated
and stil

Merge tag 'v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into mlx5-next

Linux 5.1-rc1

We forgot to reset the branch last merge window thus mlx5-next is outdated
and still based on 5.0-rc2. This merge commit is needed to sync mlx5-next
branch with 5.1-rc1.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

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Merge tag 'drm-intel-next-2019-04-04' into gvt-next

Merge back drm-intel-next for engine name definition refinement
and 54939ea0bd85 ("drm/i915: Switch to use HWS indices rather than addresses")
tha

Merge tag 'drm-intel-next-2019-04-04' into gvt-next

Merge back drm-intel-next for engine name definition refinement
and 54939ea0bd85 ("drm/i915: Switch to use HWS indices rather than addresses")
that would need gvt fixes to depend on.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

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Merge tag 'asoc-fix-v5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.1

A few core fixes along with the driver specific ones, mainly fixing

Merge tag 'asoc-fix-v5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.1

A few core fixes along with the driver specific ones, mainly fixing
small issues that only affect x86 platforms for various reasons (their
unusual machine enumeration mechanisms mainly, plus a fix for error
handling in topology).

There's some of the driver fixes that look larger than they are, like
the hdmi-codec changes which resulted in an indentation change, and most
of the other large changes are for new drivers like the STM32 changes.

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Merge drm/drm-next into drm-misc-next

Finally have a reason for a backmerge other than "it's been a while"!

Backmerging drm-next to -misc-next to facilitate Rob Herring's work on
Panfrost.

Signed-

Merge drm/drm-next into drm-misc-next

Finally have a reason for a backmerge other than "it's been a while"!

Backmerging drm-next to -misc-next to facilitate Rob Herring's work on
Panfrost.

Signed-off-by: Sean Paul <seanpaul@chromium.org>

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Merge tag 'v5.1-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 5.1-rc3

Sync with upstream (which now contains fbdev-v5.1 changes) to
prepare a base

Merge tag 'v5.1-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 5.1-rc3

Sync with upstream (which now contains fbdev-v5.1 changes) to
prepare a base for fbdev-v5.2 changes.

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Merge drm/drm-next into drm-intel-next-queued

This is needed to get the fourcc code merged without conflicts.

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Merge tag 'v5.1-rc2' into next-general

Merge to Linux 5.1-rc2 for subsystems to work with.

Merge remote-tracking branch 'net/master'

Merge tag 'v5.1-rc1' into spi-5.2

Linux 5.1-rc1

Merge tag 'v5.1-rc1' into regulator-5.2

Linux 5.1-rc1

Merge tag 'v5.1-rc1' into asoc-5.2

Linux 5.1-rc1

Merge tag 'v5.1-rc1' into asoc-5.1

Linux 5.1-rc1

Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86/pti update from Thomas Gleixner:
"Just a single change from the anti-performance departement:

Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86/pti update from Thomas Gleixner:
"Just a single change from the anti-performance departement:

- Add a new PR_SPEC_DISABLE_NOEXEC option which allows to apply the
speculation protections on a process without inheriting the state
on exec.

This remedies a situation where a Java-launcher has speculation
protections enabled because that's the default for JVMs which
causes the launched regular harmless processes to inherit the
protection state which results in unintended performance
degradation"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Add PR_SPEC_DISABLE_NOEXEC

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x86/speculation: Add PR_SPEC_DISABLE_NOEXEC

With the default SPEC_STORE_BYPASS_SECCOMP/SPEC_STORE_BYPASS_PRCTL mode,
the TIF_SSBD bit will be inherited when a new task is fork'ed or cloned.
It will

x86/speculation: Add PR_SPEC_DISABLE_NOEXEC

With the default SPEC_STORE_BYPASS_SECCOMP/SPEC_STORE_BYPASS_PRCTL mode,
the TIF_SSBD bit will be inherited when a new task is fork'ed or cloned.
It will also remain when a new program is execve'ed.

Only certain class of applications (like Java) that can run on behalf of
multiple users on a single thread will require disabling speculative store
bypass for security purposes. Those applications will call prctl(2) at
startup time to disable SSB. They won't rely on the fact the SSB might have
been disabled. Other applications that don't need SSBD will just move on
without checking if SSBD has been turned on or not.

The fact that the TIF_SSBD is inherited across execve(2) boundary will
cause performance of applications that don't need SSBD but their
predecessors have SSBD on to be unwittingly impacted especially if they
write to memory a lot.

To remedy this problem, a new PR_SPEC_DISABLE_NOEXEC argument for the
PR_SET_SPECULATION_CTRL option of prctl(2) is added to allow applications
to specify that the SSBD feature bit on the task structure should be
cleared whenever a new program is being execve'ed.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: KarimAllah Ahmed <karahmed@amazon.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: https://lkml.kernel.org/r/1547676096-3281-1-git-send-email-longman@redhat.com

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Merge tag 'v4.20' into for-linus

Sync with mainline to get linux/overflow.h among other things.

Merge tag 'v4.20' into next

Merge with mainline to bring in the new APIs.

Merge drm/drm-next into drm-misc-next

drm-next has been forwarded to 5.0-rc1, and we need it to apply the damage
helper for dirtyfb series from Noralf Trønnes.

Signed-off-by: Maxime Ripard <maxime.

Merge drm/drm-next into drm-misc-next

drm-next has been forwarded to 5.0-rc1, and we need it to apply the damage
helper for dirtyfb series from Noralf Trønnes.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>

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Merge drm/drm-next into drm-intel-next-queued

Generally catch up with 5.0-rc1, and specifically get the changes:

96d4f267e40f ("Remove 'type' argument from access_ok() function")
0b2c8f8b6b0c ("i91

Merge drm/drm-next into drm-intel-next-queued

Generally catch up with 5.0-rc1, and specifically get the changes:

96d4f267e40f ("Remove 'type' argument from access_ok() function")
0b2c8f8b6b0c ("i915: fix missing user_access_end() in page fault exception case")
594cc251fdd0 ("make 'user_access_begin()' do 'access_ok()'")

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

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Merge branches 'for-4.20/upstream-fixes', 'for-4.21/core', 'for-4.21/hid-asus', 'for-4.21/hid-core', 'for-4.21/hid-cougar', 'for-4.21/hidraw', 'for-4.21/highres-wheel' and 'for-4.21/ish' into for-lin

Merge branches 'for-4.20/upstream-fixes', 'for-4.21/core', 'for-4.21/hid-asus', 'for-4.21/hid-core', 'for-4.21/hid-cougar', 'for-4.21/hidraw', 'for-4.21/highres-wheel' and 'for-4.21/ish' into for-linus

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Merge branch 'fixes' into next/soc

Merge in fixes here, since the last batch didn't make it in before the
release of 4.20, and we might as well group them with this set of
patches.

* fixes: (822 co

Merge branch 'fixes' into next/soc

Merge in fixes here, since the last batch didn't make it in before the
release of 4.20, and we might as well group them with this set of
patches.

* fixes: (822 commits)
arm64: dts: renesas: draak: Fix CVBS input
ARM: dts: Fix OMAP4430 SDP Ethernet startup
ARM: dts: am335x-pdu001: Fix polarity of card detection input
ARM: OMAP1: ams-delta: Fix audio permanently muted
ARM: dts: omap5: Fix dual-role mode on Super-Speed port
arm64: dts: rockchip: fix rk3399-rockpro64 regulator gpios
ARM: dts: imx7d-nitrogen7: Fix the description of the Wifi clock
ARM: imx: update the cpu power up timing setting on i.mx6sx
Revert "arm64: dts: marvell: add CPU Idle power state support on Armada 7K/8K"
ARM: dts: imx7d-pico: Describe the Wifi clock
ARM: dts: realview: Fix some more duplicate regulator nodes
MAINTAINERS: update entry for MMP platform
ARM: mmp/mmp2: fix cpu_is_mmp2() on mmp2-dt
MAINTAINERS: mediatek: Update SoC entry
ARM: dts: bcm2837: Fix polarity of wifi reset GPIOs
+ Linux 4.20-rc5

Signed-off-by: Olof Johansson <olof@lixom.net>

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Merge tag 'v4.20-rc7' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 4.20-rc7

Sync with upstream (which now contains fbdev-v4.20 changes) to
prepare a b

Merge tag 'v4.20-rc7' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 4.20-rc7

Sync with upstream (which now contains fbdev-v4.20 changes) to
prepare a base for fbdev-v4.21 changes.

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Merge tag 'spi-nor/for-4.21' of git://git.infradead.org/linux-mtd into mtd/next

Core changes:
- Parse the 4BAIT SFDP section
- Add a bunch of SPI NOR entries to the flash_info table
- Add the concep

Merge tag 'spi-nor/for-4.21' of git://git.infradead.org/linux-mtd into mtd/next

Core changes:
- Parse the 4BAIT SFDP section
- Add a bunch of SPI NOR entries to the flash_info table
- Add the concept of SFDP fixups and use it to fix a bug on MX25L25635F
- A bunch of minor cleanups/comestic changes

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Merge tag 'asoc-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next

ASoC: Updates for v4.21

Not much work on the core this time around but we've seen quite a bit of

Merge tag 'asoc-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next

ASoC: Updates for v4.21

Not much work on the core this time around but we've seen quite a bit of
driver work, including on the generic DT drivers. There's also a large
part of the diff from a merge of the DaVinci and OMAP directories, along
with some active development there:

- Preparatory work from Morimoto-san for merging the audio-graph and
audio-graph-scu cards.
- A merge of the TI OMAP and DaVinci directories, the OMAP product line
has been merged into the DaVinci product line so there is now a lot
of IP sharing which meant that the split directories just got in the
way. This has pulled in a few architecture changes as well.
- A big cleanup of the Maxim MAX9867 driver from Ladislav Michl.
- Support for Asahi Kaesi AKM4118, AMD ACP3x, Intel platforms with
RT5660, Meson AXG S/PDIF inputs, several Qualcomm IPs and Xilinx I2S
controllers.

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