linux/arch
David Woodhouse 2961298efe x86/cpufeatures: Clean up Spectre v2 related CPUID flags
We want to expose the hardware features simply in /proc/cpuinfo as "ibrs",
"ibpb" and "stibp". Since AMD has separate CPUID bits for those, use them
as the user-visible bits.

When the Intel SPEC_CTRL bit is set which indicates both IBRS and IBPB
capability, set those (AMD) bits accordingly. Likewise if the Intel STIBP
bit is set, set the AMD STIBP that's used for the generic hardware
capability.

Hide the rest from /proc/cpuinfo by putting "" in the comments. Including
RETPOLINE and RETPOLINE_AMD which shouldn't be visible there. There are
patches to make the sysfs vulnerabilities information non-readable by
non-root, and the same should apply to all information about which
mitigations are actually in use. Those *shouldn't* appear in /proc/cpuinfo.

The feature bit for whether IBPB is actually used, which is needed for
ALTERNATIVEs, is renamed to X86_FEATURE_USE_IBPB.

Originally-by: Borislav Petkov <bp@suse.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1517070274-12128-2-git-send-email-dwmw@amazon.co.uk
2018-01-27 19:10:44 +01:00
..
alpha License cleanup: add SPDX license identifiers to some files 2017-11-02 10:04:46 -07:00
arc License cleanup: add SPDX license identifiers to some files 2017-11-02 10:04:46 -07:00
arm Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm 2017-11-09 17:41:39 -08:00
arm64 Merge branch 'upstream-acpi-fixes' into WIP.x86/pti.base 2017-12-17 13:09:31 +01:00
blackfin License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
c6x License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
cris License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
frv License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
h8300 License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
hexagon License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
ia64 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-05 12:14:50 -08:00
m32r License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
m68k License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
metag License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
microblaze License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
mips MIPS: AR7: Ensure that serial ports are properly set up 2017-11-08 14:57:55 +00:00
mn10300 License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
nios2 License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
openrisc License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
parisc License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
powerpc arch, mm: Allow arch_dup_mmap() to fail 2017-12-22 20:13:01 +01:00
s390 License cleanup: add SPDX license identifiers to some files 2017-11-02 10:04:46 -07:00
score License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
sh License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
sparc License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
tile Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 2017-11-03 10:36:43 -07:00
um arch, mm: Allow arch_dup_mmap() to fail 2017-12-22 20:13:01 +01:00
unicore32 arch, mm: Allow arch_dup_mmap() to fail 2017-12-22 20:13:01 +01:00
x86 x86/cpufeatures: Clean up Spectre v2 related CPUID flags 2018-01-27 19:10:44 +01:00
xtensa License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
.gitignore
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00