linux-stable.git/arch/x86/include/asm/microcode.h, branch linux-4.3.y

x86/microcode: Parse built-in microcode early

2015-05-06T09:24:53+00:00

Apparently, people do build microcode into the kernel image, i.e.
CONFIG_FIRMWARE_IN_KERNEL=y.

Make that work in the early loader which is where microcode should be
preferably loaded anyway.

Note that you need to specify the microcode filename with the path
relative to the toplevel firmware directory (the same like the late
loading method) in CONFIG_EXTRA_FIRMWARE=y so that early loader can
find it.

I.e., something like this (Intel variant):

  CONFIG_FIRMWARE_IN_KERNEL=y
  CONFIG_EXTRA_FIRMWARE="intel-ucode/06-3a-09"
  CONFIG_EXTRA_FIRMWARE_DIR="/lib/firmware/"

While at it, add me to the loader copyright boilerplate.

Signed-off-by: Borislav Petkov 
Cc: Borislav Petkov 
Cc: Daniel J Blueman 
Cc: H. Peter Anvin 
Cc: Thomas Gleixner 
Signed-off-by: Ingo Molnar

x86/microcode: Consolidate family,model, ... code

2015-03-02T19:32:07+00:00

... to the header. Split the family acquiring function into a
main one, doing CPUID and a helper which computes the extended
family and is used in multiple places. Get rid of the locally-grown
get_x86_{family,model}().

While at it, rename local variables to something more descriptive and
vertically align assignments for better readability.

There should be no functionality change resulting from this patch.

Signed-off-by: Borislav Petkov

x86, microcode: Reload microcode on resume

2014-12-06T12:03:03+00:00

Normally, we do reapply microcode on resume. However, in the cases where
that microcode comes from the early loader and the late loader hasn't
been utilized yet, there's no easy way for us to go and apply the patch
applied during boot by the early loader.

Thus, reuse the patch stashed by the early loader for the BSP.

Signed-off-by: Borislav Petkov

x86, microcode: Add a disable chicken bit

2014-05-21T03:21:27+00:00

Add a cmdline param which disables the microcode loader. This is useful
mostly in debugging situations where we want to turn off microcode
loading, both early from the initrd and late, as a means to be able to
rule out its influence on the machine.

Signed-off-by: Borislav Petkov 
Link: http://lkml.kernel.org/r/1400525957-11525-3-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin

x86, microcode: Share native MSR accessing variants

2014-01-13T18:57:27+00:00

We want to use those in AMD's early loading path too. Also, add a
native_wrmsrl variant.

Signed-off-by: Borislav Petkov 
Tested-by: Aravind Gopalakrishnan

x86: delete __cpuinit usage from all x86 files

2013-07-14T23:36:56+00:00

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/x86 uses of the __cpuinit macros from
all C files.  x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: x86@kernel.org
Acked-by: Ingo Molnar 
Acked-by: Thomas Gleixner 
Acked-by: H. Peter Anvin 
Signed-off-by: Paul Gortmaker

x86: Fix section mismatch on load_ucode_ap

2013-06-19T21:43:59+00:00

We are in the process of removing all the __cpuinit annotations.
While working on making that change, an existing problem was
made evident:

  WARNING: arch/x86/kernel/built-in.o(.text+0x198f2): Section mismatch
  in reference from the function cpu_init() to the function
  .init.text:load_ucode_ap()   The function cpu_init() references
  the function __init load_ucode_ap().  This is often because cpu_init
  lacks a __init annotation or the annotation of load_ucode_ap is wrong.

This now appears because in my working tree, cpu_init() is no longer
tagged as __cpuinit, and so the audit picks up the mismatch.  The 2nd
hypothesis from the audit is the correct one, as there was an incorrect
__init tag on the prototype in the header (but __cpuinit was used on
the function itself.)

The audit is telling us that the prototype's __init annotation took
effect and the function did land in the .init.text section.  Checking
with objdump on a mainline tree that still has __cpuinit shows that
the __cpuinit on the function takes precedence over the __init on the
prototype, but that won't be true once we make __cpuinit a no-op.

Even though we are removing __cpuinit, we temporarily align both
the function and the prototype on __cpuinit so that the changeset
can be applied to stable trees  if desired.

[ hpa: build fix only, no object code change ]

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: stable  # 3.9+
Signed-off-by: Paul Gortmaker 
Link: http://lkml.kernel.org/r/1371654926-11729-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin

x86/microcode_core_early.c: Define interfaces for early loading ucode

2013-01-31T21:19:12+00:00

Define interfaces load_ucode_bsp() and load_ucode_ap() to load ucode on BSP and
AP in early boot time. These are generic interfaces. Internally they call
vendor specific implementations.

Signed-off-by: Fenghua Yu 
Link: http://lkml.kernel.org/r/1356075872-3054-6-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin

x86, microcode: Add a refresh firmware flag to ->request_microcode_fw

2012-08-22T23:15:58+00:00

This is done in preparation for teaching the ucode driver to either load
a new ucode patches container from userspace or use an already cached
version. No functionality change in this patch.

Signed-off-by: Borislav Petkov 
Link: http://lkml.kernel.org/r/1344361461-10076-10-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin

x86, microcode, AMD: Remove useless get_ucode_data wrapper

2012-08-22T23:15:26+00:00

get_ucode_data was a trivial memcpy wrapper. Remove it so as not to
obfuscate code unnecessarily with no obvious gain.

No functional change.

Signed-off-by: Borislav Petkov 
Link: http://lkml.kernel.org/r/1344361461-10076-7-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin