Patch "x86/fpu: Remove the explicit clearing of XSAVE dependent features" has been added to the 4.14-stable tree

Patch "x86/fpu: Remove the explicit clearing of XSAVE dependent features" has been added to the 4.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    x86/fpu: Remove the explicit clearing of XSAVE dependent features

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-fpu-remove-the-explicit-clearing-of-xsave-dependent-features.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 73e3a7d2a7c3be29a5a22b85026f6cfa5664267f Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@linux.intel.com>
Date: Fri, 13 Oct 2017 14:56:45 -0700
Subject: x86/fpu: Remove the explicit clearing of XSAVE dependent features

From: Andi Kleen <ak@linux.intel.com>

commit 73e3a7d2a7c3be29a5a22b85026f6cfa5664267f upstream.

Clearing a CPU feature with setup_clear_cpu_cap() clears all features
which depend on it. Expressing feature dependencies in one place is
easier to maintain than keeping functions like
fpu__xstate_clear_all_cpu_caps() up to date.

The features which depend on XSAVE have their dependency expressed in the
dependency table, so its sufficient to clear X86_FEATURE_XSAVE.

Remove the explicit clearing of XSAVE dependent features.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171013215645.23166-6-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/kernel/fpu/xstate.c |   20 --------------------
 1 file changed, 20 deletions(-)

--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -73,26 +73,6 @@ unsigned int fpu_user_xstate_size;
 void fpu__xstate_clear_all_cpu_caps(void)
 {
 	setup_clear_cpu_cap(X86_FEATURE_XSAVE);
-	setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
-	setup_clear_cpu_cap(X86_FEATURE_XSAVEC);
-	setup_clear_cpu_cap(X86_FEATURE_XSAVES);
-	setup_clear_cpu_cap(X86_FEATURE_AVX);
-	setup_clear_cpu_cap(X86_FEATURE_AVX2);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512F);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512IFMA);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512PF);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512ER);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512CD);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512DQ);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512BW);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512VL);
-	setup_clear_cpu_cap(X86_FEATURE_MPX);
-	setup_clear_cpu_cap(X86_FEATURE_XGETBV1);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512VBMI);
-	setup_clear_cpu_cap(X86_FEATURE_PKU);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512_4VNNIW);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512_4FMAPS);
-	setup_clear_cpu_cap(X86_FEATURE_AVX512_VPOPCNTDQ);
 }
 
 /*


Patches currently in stable-queue which might be from ak@linux.intel.com are

queue-4.14/bitops-add-clear-set_bit32-to-linux-bitops.h.patch
queue-4.14/x86-fpu-remove-the-explicit-clearing-of-xsave-dependent-features.patch
queue-4.14/x86-cpuid-add-generic-table-for-cpuid-dependencies.patch
queue-4.14/x86-cpuid-prevent-out-of-bound-access-in-do_clear_cpu_cap.patch
queue-4.14/x86-fpu-parse-clearcpuid-as-early-xsave-argument.patch
queue-4.14/x86-fpu-make-xsave-check-the-base-cpuid-features-before-enabling.patch