linux-toradex.git/Documentation, branch v4.9.75

x86/kaiser: Check boottime cmdline params

2018-01-05T14:46:35+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

2018-01-05T14:46:34+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

2018-01-05T14:46:34+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

2018-01-02T19:35:09+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

dt-bindings: usb: fix reg-property port-number range

2017-12-14T08:28:23+00:00

[ Upstream commit f42ae7b0540937e00fe005812997f126aaac4bc2 ]

The USB hub port-number range for USB 2.0 is 1-255 and not 1-31 which
reflects an arbitrary limit set by the current Linux implementation.

Note that for USB 3.1 hubs the valid range is 1-15.

Increase the documented valid range in the binding to 255, which is the
maximum allowed by the specifications.

Signed-off-by: Johan Hovold 
Signed-off-by: Rob Herring 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

hwmon: (jc42) optionally try to disable the SMBUS timeout

2017-12-05T10:24:34+00:00

commit 68615eb01f82256c19e41967bfb3eef902f77033 upstream.

With a nxp,se97 chip on an atmel sama5d31 board, the I2C adapter driver
is not always capable of avoiding the 25-35 ms timeout as specified by
the SMBUS protocol. This may cause silent corruption of the last bit of
any transfer, e.g. a one is read instead of a zero if the sensor chip
times out. This also affects the eeprom half of the nxp-se97 chip, where
this silent corruption was originally noticed. Other I2C adapters probably
suffer similar issues, e.g. bit-banging comes to mind as risky...

The SMBUS register in the nxp chip is not a standard Jedec register, but
it is not special to the nxp chips either, at least the atmel chips
have the same mechanism. Therefore, do not special case this on the
manufacturer, it is opt-in via the device property anyway.

Signed-off-by: Peter Rosin 
Acked-by: Rob Herring 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

Revert "dt-bindings: Add LEGO MINDSTORMS EV3 compatible specification"

2017-11-21T08:23:28+00:00

This reverts commit 852bf68b7a62195c3c0c63f3b11f3f30958fc220.

As Ben pointed out, these drivers don't exist in <=4.9.

Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Revert "dt-bindings: Add vendor prefix for LEGO"

2017-11-21T08:23:28+00:00

This reverts commit 04e13a5ec96db94c1cc8ce7b0b1e1b626e0c00c7.

As Ben pointed out, these drivers don't exist in <=4.9.

Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dt-bindings: Add vendor prefix for LEGO

2017-11-15T14:53:14+00:00

[ Upstream commit 7dcc31e2e68a386a29070384b51683ece80982bf ]

Add a vendor prefix for LEGO Systems A/S

Acked-by: Rob Herring 
Signed-off-by: David Lechner 
Signed-off-by: Sekhar Nori 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

dt-bindings: Add LEGO MINDSTORMS EV3 compatible specification

2017-11-15T14:53:14+00:00

[ Upstream commit 21078ab174c99885ca83a5c32db0d33b1617745e ]

This adds the board level device tree specification for LEGO MINDSTORMS EV3

Acked-by: Rob Herring 
Signed-off-by: David Lechner 
Signed-off-by: Sekhar Nori 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman