x86/cpufeatures: Generate the <asm/cpufeaturemasks.h> header based on build config

Introduce an AWK script to auto-generate the <asm/cpufeaturemasks.h> header
with required and disabled feature mask

x86/cpufeatures: Generate the <asm/cpufeaturemasks.h> header based on build config

Introduce an AWK script to auto-generate the <asm/cpufeaturemasks.h> header
with required and disabled feature masks based on <asm/cpufeatures.h>
and the current build config.

Thus for any CPU feature with a build config, e.g., X86_FRED, simply add:

config X86_DISABLED_FEATURE_FRED
def_bool y
depends on !X86_FRED

to arch/x86/Kconfig.cpufeatures, instead of adding a conditional CPU
feature disable flag, e.g., DISABLE_FRED.

Lastly, the generated required and disabled feature masks will be added to
their corresponding feature masks for this particular compile-time
configuration.

[ Xin: build integration improvements ]
[ mingo: Improved changelog and comments ]

Signed-off-by: H. Peter Anvin (Intel) <[email protected]>
Signed-off-by: Xin Li (Intel) <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Reviewed-by: Nikolay Borisov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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x86: Prepare asm files for straight-line-speculation

Replace all ret/retq instructions with RET in preparation of making
RET a macro. Since AS is case insensitive it's a big no-op without
RET define

x86: Prepare asm files for straight-line-speculation

Replace all ret/retq instructions with RET in preparation of making
RET a macro. Since AS is case insensitive it's a big no-op without
RET defined.

find arch/x86/ -name \*.S | while read file
do
sed -i 's/\<ret[q]*\>/RET/' $file
done

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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x86/asm: Annotate local pseudo-functions

Use the newly added SYM_CODE_START_LOCAL* to annotate beginnings of
all pseudo-functions (those ending with END until now) which do not
have ".globl" annotat

x86/asm: Annotate local pseudo-functions

Use the newly added SYM_CODE_START_LOCAL* to annotate beginnings of
all pseudo-functions (those ending with END until now) which do not
have ".globl" annotation. This is needed to balance END for tools that
generate debuginfo. Note that ENDs are switched to SYM_CODE_END too so
that everybody can see the pairing.

C-like functions (which handle frame ptr etc.) are not annotated here,
hence SYM_CODE_* macros are used here, not SYM_FUNC_*. Note that the
32bit version of early_idt_handler_common already had ENDPROC -- switch
that to SYM_CODE_END for the same reason as above (and to be the same as
64bit).

While early_idt_handler_common is LOCAL, it's name is not prepended with
".L" as it happens to appear in call traces.

bad_get_user*, and bad_put_user are now aligned, as they are separate
functions. They do not mind to be aligned -- no need to be compact
there.

early_idt_handler_common is aligned now too, as it is after
early_idt_handler_array, so as well no need to be compact there.

verify_cpu is self-standing and included in other .S files, so align it
too.

The others have alignment preserved to what it used to be (using the
_NOALIGN variant of macros).

Signed-off-by: Jiri Slaby <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Cc: Alexios Zavras <[email protected]>
Cc: Allison Randal <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Cao jin <[email protected]>
Cc: Enrico Weigelt <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: [email protected]
Cc: Maran Wilson <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: x86-ml <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230

Based on 2 normalized pattern(s):

this source code is licensed under the gnu general public license
version 2 see the file cop

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230

Based on 2 normalized pattern(s):

this source code is licensed under the gnu general public license
version 2 see the file copying for more details

this source code is licensed under general public license version 2
see

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 52 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Enrico Weigelt <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Alexios Zavras <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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x86/boot: Annotate verify_cpu() as a callable function

verify_cpu() is a callable function. Annotate it as such.

Signed-off-by: Josh Poimboeuf <[email protected]>
Cc: Andy Lutomirski <luto@kerne

x86/boot: Annotate verify_cpu() as a callable function

verify_cpu() is a callable function. Annotate it as such.

Signed-off-by: Josh Poimboeuf <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/293024b8a080832075312f38c07ccc970fc70292.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <[email protected]>

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x86/cpufeature: Carve out X86_FEATURE_*

Move them to a separate header and have the following
dependency:

x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h

This makes it easier to use the

x86/cpufeature: Carve out X86_FEATURE_*

Move them to a separate header and have the following
dependency:

x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h

This makes it easier to use the header in asm code and not
include the whole cpufeature.h and add guards for asm.

Suggested-by: H. Peter Anvin <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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x86/boot: Hide local labels in verify_cpu()

... from the final ELF image's symbol table as they're not
really needed there.

Before:

$ readelf -a vmlinux | grep verify_cpu
43: ffffffff810001a9

x86/boot: Hide local labels in verify_cpu()

... from the final ELF image's symbol table as they're not
really needed there.

Before:

$ readelf -a vmlinux | grep verify_cpu
43: ffffffff810001a9 0 NOTYPE LOCAL DEFAULT 1 verify_cpu
45: ffffffff8100028f 0 NOTYPE LOCAL DEFAULT 1 verify_cpu_no_longmode
46: ffffffff810001de 0 NOTYPE LOCAL DEFAULT 1 verify_cpu_noamd
47: ffffffff8100022b 0 NOTYPE LOCAL DEFAULT 1 verify_cpu_check
48: ffffffff8100021c 0 NOTYPE LOCAL DEFAULT 1 verify_cpu_clear_xd
49: ffffffff81000263 0 NOTYPE LOCAL DEFAULT 1 verify_cpu_sse_test
50: ffffffff81000296 0 NOTYPE LOCAL DEFAULT 1 verify_cpu_sse_ok

After:

$ readelf -a vmlinux | grep verify_cpu
43: ffffffff810001a9 0 NOTYPE LOCAL DEFAULT 1 verify_cpu

No functionality change.

Signed-off-by: Borislav Petkov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Quentin Casasnovas <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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x86/cpu: Call verify_cpu() after having entered long mode too

When we get loaded by a 64-bit bootloader, kernel entry point is
startup_64 in head_64.S. We don't trust any and all bootloaders because

x86/cpu: Call verify_cpu() after having entered long mode too

When we get loaded by a 64-bit bootloader, kernel entry point is
startup_64 in head_64.S. We don't trust any and all bootloaders because
some will fiddle with CPU configuration so we go ahead and massage each
CPU into sanity again.

For example, some dell BIOSes have this XD disable feature which set
IA32_MISC_ENABLE[34] and disable NX. This might be some dumb workaround
for other OSes but Linux sure doesn't need it.

A similar thing is present in the Surface 3 firmware - see
https://bugzilla.kernel.org/show_bug.cgi?id=106051 - which sets this bit
only on the BSP:

# rdmsr -a 0x1a0
400850089
850089
850089
850089

I know, right?!

There's not even an off switch in there.

So fix all those cases by sanitizing the 64-bit entry point too. For
that, make verify_cpu() callable in 64-bit mode also.

Requested-and-debugged-by: "H. Peter Anvin" <[email protected]>
Reported-and-tested-by: Bastien Nocera <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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x86: Fix common misspellings

They were generated by 'codespell' and then manually reviewed.

Signed-off-by: Lucas De Marchi <[email protected]>
Cc: [email protected]
LKML-Reference: <13

x86: Fix common misspellings

They were generated by 'codespell' and then manually reviewed.

Signed-off-by: Lucas De Marchi <[email protected]>
Cc: [email protected]
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

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x86: Fix included-by file reference comments

Adjust the paths for files that are including verify_cpu.S.

Reported-by: Yinghai Lu <[email protected]>
Signed-off-by: Kees Cook <[email protected]

x86: Fix included-by file reference comments

Adjust the paths for files that are including verify_cpu.S.

Reported-by: Yinghai Lu <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Cc: Alan Cox <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

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x86, cpu: Call verify_cpu during 32bit CPU startup

The XD_DISABLE-clearing side-effect needs to happen for both 32bit
and 64bit, but the 32bit init routines were not calling verify_cpu()
yet. This a

x86, cpu: Call verify_cpu during 32bit CPU startup

The XD_DISABLE-clearing side-effect needs to happen for both 32bit
and 64bit, but the 32bit init routines were not calling verify_cpu()
yet. This adds that call to gain the side-effect.

The longmode/SSE tests being performed in verify_cpu() need to happen very
early for 64bit but not for 32bit. Instead of including it in two places
for 32bit, we can just include it once in arch/x86/kernel/head_32.S.

Signed-off-by: Kees Cook <[email protected]>
LKML-Reference: <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Acked-by: Alan Cox <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>

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x86, cpu: Clear XD_DISABLED flag on Intel to regain NX

Intel CPUs have an additional MSR bit to indicate if the BIOS was
configured to disable the NX cpu feature. This bit was traditionally
used for

x86, cpu: Clear XD_DISABLED flag on Intel to regain NX

Intel CPUs have an additional MSR bit to indicate if the BIOS was
configured to disable the NX cpu feature. This bit was traditionally
used for operating systems that did not understand how to handle the
NX bit. Since Linux understands this, this BIOS flag should be ignored
by default.

In a review[1] of reported hardware being used by Ubuntu bug reporters,
almost 10% of systems had an incorrectly configured BIOS, leaving their
systems unable to use the NX features of their CPU.

This change will clear the MSR_IA32_MISC_ENABLE_XD_DISABLE bit so that NX
cannot be inappropriately controlled by the BIOS on Intel CPUs. If, under
very strange hardware configurations, NX actually needs to be disabled,
"noexec=off" can be used to restore the prior behavior.

[1] http://www.outflux.net/blog/archives/2010/02/18/data-mining-for-nx-bit/

Signed-off-by: Kees Cook <[email protected]>
LKML-Reference: <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Acked-by: Alan Cox <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>

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x86, cpu: Rename verify_cpu_64.S to verify_cpu.S

The code is 32bit already, and can be used in 32bit routines.

Signed-off-by: Kees Cook <[email protected]>
LKML-Reference: <1289414154-7829-2-

x86, cpu: Rename verify_cpu_64.S to verify_cpu.S

The code is 32bit already, and can be used in 32bit routines.

Signed-off-by: Kees Cook <[email protected]>
LKML-Reference: <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Acked-by: Alan Cox <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>

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