linux-stable.git/Documentation, branch v4.4.112

sysfs/cpu: Fix typos in vulnerability documentation

2018-01-17T08:35:33+00:00

commit 9ecccfaa7cb5249bd31bdceb93fcf5bedb8a24d8 upstream.

Fixes: 87590ce6e ("sysfs/cpu: Add vulnerability folder")
Signed-off-by: David Woodhouse 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

sysfs/cpu: Add vulnerability folder

2018-01-17T08:35:33+00:00

commit 87590ce6e373d1a5401f6539f0c59ef92dd924a9 upstream.

As the meltdown/spectre problem affects several CPU architectures, it makes
sense to have common way to express whether a system is affected by a
particular vulnerability or not. If affected the way to express the
mitigation should be common as well.

Create /sys/devices/system/cpu/vulnerabilities folder and files for
meltdown, spectre_v1 and spectre_v2.

Allow architectures to override the show function.

Signed-off-by: Thomas Gleixner 
Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: Konrad Rzeszutek Wilk 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Borislav Petkov 
Cc: David Woodhouse 
Link: https://lkml.kernel.org/r/20180107214913.096657732@linutronix.de
Signed-off-by: Greg Kroah-Hartman

x86/Documentation: Add PTI description

2018-01-17T08:35:32+00:00

commit 01c9b17bf673b05bb401b76ec763e9730ccf1376 upstream.

Add some details about how PTI works, what some of the downsides
are, and how to debug it when things go wrong.

Also document the kernel parameter: 'pti/nopti'.

Signed-off-by: Dave Hansen 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Randy Dunlap 
Reviewed-by: Kees Cook 
Cc: Moritz Lipp 
Cc: Daniel Gruss 
Cc: Michael Schwarz 
Cc: Richard Fellner 
Cc: Andy Lutomirski 
Cc: Linus Torvalds 
Cc: Hugh Dickins 
Cc: Andi Lutomirsky 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180105174436.1BC6FA2B@viggo.jf.intel.com
Signed-off-by: Greg Kroah-Hartman

x86/kaiser: Check boottime cmdline params

2018-01-05T14:44:25+00:00

AMD (and possibly other vendors) are not affected by the leak
KAISER is protecting against.

Keep the "nopti" for traditional reasons and add pti=
like upstream.

Signed-off-by: Borislav Petkov 
Signed-off-by: Greg Kroah-Hartman

x86/kaiser: Rename and simplify X86_FEATURE_KAISER handling

2018-01-05T14:44:25+00:00

Concentrate it in arch/x86/mm/kaiser.c and use the upstream string "nopti".

Signed-off-by: Borislav Petkov 
Signed-off-by: Greg Kroah-Hartman

kaiser: add "nokaiser" boot option, using ALTERNATIVE

2018-01-05T14:44:25+00:00

Added "nokaiser" boot option: an early param like "noinvpcid".
Most places now check int kaiser_enabled (#defined 0 when not
CONFIG_KAISER) instead of #ifdef CONFIG_KAISER; but entry_64.S
and entry_64_compat.S are using the ALTERNATIVE technique, which
patches in the preferred instructions at runtime.  That technique
is tied to x86 cpu features, so X86_FEATURE_KAISER is fabricated.

Prior to "nokaiser", Kaiser #defined _PAGE_GLOBAL 0: revert that,
but be careful with both _PAGE_GLOBAL and CR4.PGE: setting them when
nokaiser like when !CONFIG_KAISER, but not setting either when kaiser -
neither matters on its own, but it's hard to be sure that _PAGE_GLOBAL
won't get set in some obscure corner, or something add PGE into CR4.
By omitting _PAGE_GLOBAL from __supported_pte_mask when kaiser_enabled,
all page table setup which uses pte_pfn() masks it out of the ptes.

It's slightly shameful that the same declaration versus definition of
kaiser_enabled appears in not one, not two, but in three header files
(asm/kaiser.h, asm/pgtable.h, asm/tlbflush.h).  I felt safer that way,
than with #including any of those in any of the others; and did not
feel it worth an asm/kaiser_enabled.h - kernel/cpu/common.c includes
them all, so we shall hear about it if they get out of synch.

Cleanups while in the area: removed the silly #ifdef CONFIG_KAISER
from kaiser.c; removed the unused native_get_normal_pgd(); removed
the spurious reg clutter from SWITCH_*_CR3 macro stubs; corrected some
comments.  But more interestingly, set CR4.PSE in secondary_startup_64:
the manual is clear that it does not matter whether it's 0 or 1 when
4-level-pts are enabled, but I was distracted to find cr4 different on
BSP and auxiliaries - BSP alone was adding PSE, in probe_page_size_mask().

Signed-off-by: Hugh Dickins 
Acked-by: Jiri Kosina 
Signed-off-by: Greg Kroah-Hartman

x86/mm: Add the 'nopcid' boot option to turn off PCID

2018-01-02T19:33:23+00:00

commit 0790c9aad84901ca1bdc14746175549c8b5da215 upstream.

The parameter is only present on x86_64 systems to save a few bytes,
as PCID is always disabled on x86_32.

Signed-off-by: Andy Lutomirski 
Reviewed-by: Nadav Amit 
Reviewed-by: Borislav Petkov 
Reviewed-by: Thomas Gleixner 
Cc: Andrew Morton 
Cc: Arjan van de Ven 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Mel Gorman 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/8bbb2e65bcd249a5f18bfb8128b4689f08ac2b60.1498751203.git.luto@kernel.org
Signed-off-by: Ingo Molnar 
Cc: Hugh Dickins 
Signed-off-by: Greg Kroah-Hartman

x86/mm: Add a 'noinvpcid' boot option to turn off INVPCID

2017-12-25T13:22:08+00:00

commit d12a72b844a49d4162f24cefdab30bed3f86730e upstream.

This adds a chicken bit to turn off INVPCID in case something goes
wrong.  It's an early_param() because we do TLB flushes before we
parse __setup() parameters.

Signed-off-by: Andy Lutomirski 
Reviewed-by: Borislav Petkov 
Cc: Andrew Morton 
Cc: Andrey Ryabinin 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Dave Hansen 
Cc: Denys Vlasenko 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Luis R. Rodriguez 
Cc: Oleg Nesterov 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Toshi Kani 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/f586317ed1bc2b87aee652267e515b90051af385.1454096309.git.luto@kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

Revert "drm: bridge: add DT bindings for TI ths8135"

2017-11-02T08:40:50+00:00

This reverts commit 11bf4a8e1d5a300b38ca4bbe1156716b0174f2da which is
commit 2e644be30fcc08c736f66b60f4898d274d4873ab upstream.

Ben pointed out that there is no driver or device trees referencing this
device in 4.4-stable, so the patch should not be present there.

Reported-by: Ben Hutchings 
Cc: Bartosz Golaszewski 
Cc: Laurent Pinchart 
Cc: Rob Herring 
Cc: Archit Taneja 
Cc: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

iio: adc: hx711: Add DT binding for avia,hx711

2017-10-08T08:14:17+00:00

[ Upstream commit ff1293f67734da68e23fecb6ecdae7112b8c43f9 ]

Add DT bindings for avia,hx711
Add vendor avia to vendor list

Signed-off-by: Andreas Klinger 
Acked-by: Rob Herring 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman