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x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys
authorDave Hansen <dave.hansen@linux.intel.com>
Sat, 14 Jul 2018 09:28:30 +0000 (02:28 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 17 Jul 2018 09:31:45 +0000 (11:31 +0200)
commit793ea13ecc8d46668c0d24d6e5d4487a25eab877
tree828cdc347a4bb928d89d14ac25d9ea5d4c99641b
parent9cc52d168fcb4152132b0ba067db4c1da1bdca67
x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys

commit e8df1a95b685af84a81698199ee206e0e66a8b44 upstream

When I added support for the Memory Protection Keys processor
feature, I had to reindent the REQUIRED/DISABLED_MASK macros, and
also consult the later cpufeature words.

I'm not quite sure how I bungled it, but I consulted the wrong
word at the end.  This only affected required or disabled cpu
features in cpufeature words 14, 15 and 16.  So, only Protection
Keys itself was screwed over here.

The result was that if you disabled pkeys in your .config, you
might still see some code show up that should have been compiled
out.  There should be no functional problems, though.

In verifying this patch I also realized that the DISABLE_PKU/OSPKE
macros were defined backwards and that the cpu_has() check in
setup_pku() was not doing the compile-time disabled checks.

So also fix the macro for DISABLE_PKU/OSPKE and add a compile-time
check for pkeys being enabled in setup_pku().

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: dfb4a70f20c5 ("x86/cpufeature, x86/mm/pkeys: Add protection keys related CPUID definitions")
Link: http://lkml.kernel.org/r/20160513221328.C200930B@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/include/asm/cpufeature.h
arch/x86/include/asm/disabled-features.h