patches/kernel/0069-x86-fpu-Remove-the-explicit-clearing-of-XSAVE-depend.patch

   1 From 9b2405a12593b1ba7894cf249ddeada92a658463 Mon Sep 17 00:00:00 2001
   2 From: Andi Kleen <ak@linux.intel.com>
   3 Date: Fri, 13 Oct 2017 14:56:45 -0700
   4 Subject: [PATCH 069/241] x86/fpu: Remove the explicit clearing of XSAVE
   5  dependent features
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 CVE-2017-5754
  11
  12 Clearing a CPU feature with setup_clear_cpu_cap() clears all features
  13 which depend on it. Expressing feature dependencies in one place is
  14 easier to maintain than keeping functions like
  15 fpu__xstate_clear_all_cpu_caps() up to date.
  16
  17 The features which depend on XSAVE have their dependency expressed in the
  18 dependency table, so its sufficient to clear X86_FEATURE_XSAVE.
  19
  20 Remove the explicit clearing of XSAVE dependent features.
  21
  22 Signed-off-by: Andi Kleen <ak@linux.intel.com>
  23 Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
  24 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  25 Cc: Peter Zijlstra <peterz@infradead.org>
  26 Link: http://lkml.kernel.org/r/20171013215645.23166-6-andi@firstfloor.org
  27 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  28 (cherry picked from commit 73e3a7d2a7c3be29a5a22b85026f6cfa5664267f)
  29 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  30 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  31 (cherry picked from commit af445f9ba8bb30b47ccb5247b8f5ba28c9f2be3e)
  32 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  33 ---
  34  arch/x86/kernel/fpu/xstate.c | 20 --------------------
  35  1 file changed, 20 deletions(-)
  36
  37 diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
  38 index 3abe85b08234..fd6882c42246 100644
  39 --- a/arch/x86/kernel/fpu/xstate.c
  40 +++ b/arch/x86/kernel/fpu/xstate.c
  41 @@ -73,26 +73,6 @@ unsigned int fpu_user_xstate_size;
  42  void fpu__xstate_clear_all_cpu_caps(void)
  43  {
  44         setup_clear_cpu_cap(X86_FEATURE_XSAVE);
  45 -       setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
  46 -       setup_clear_cpu_cap(X86_FEATURE_XSAVEC);
  47 -       setup_clear_cpu_cap(X86_FEATURE_XSAVES);
  48 -       setup_clear_cpu_cap(X86_FEATURE_AVX);
  49 -       setup_clear_cpu_cap(X86_FEATURE_AVX2);
  50 -       setup_clear_cpu_cap(X86_FEATURE_AVX512F);
  51 -       setup_clear_cpu_cap(X86_FEATURE_AVX512IFMA);
  52 -       setup_clear_cpu_cap(X86_FEATURE_AVX512PF);
  53 -       setup_clear_cpu_cap(X86_FEATURE_AVX512ER);
  54 -       setup_clear_cpu_cap(X86_FEATURE_AVX512CD);
  55 -       setup_clear_cpu_cap(X86_FEATURE_AVX512DQ);
  56 -       setup_clear_cpu_cap(X86_FEATURE_AVX512BW);
  57 -       setup_clear_cpu_cap(X86_FEATURE_AVX512VL);
  58 -       setup_clear_cpu_cap(X86_FEATURE_MPX);
  59 -       setup_clear_cpu_cap(X86_FEATURE_XGETBV1);
  60 -       setup_clear_cpu_cap(X86_FEATURE_AVX512VBMI);
  61 -       setup_clear_cpu_cap(X86_FEATURE_PKU);
  62 -       setup_clear_cpu_cap(X86_FEATURE_AVX512_4VNNIW);
  63 -       setup_clear_cpu_cap(X86_FEATURE_AVX512_4FMAPS);
  64 -       setup_clear_cpu_cap(X86_FEATURE_AVX512_VPOPCNTDQ);
  65  }
  66
  67  /*
  68 --
  69 2.14.2
  70