git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 594a30fb12424717a41c62323d2a8bf167dbccad Mon Sep 17 00:00:00 2001
   2 From: Hans de Goede <hdegoede@redhat.com>
   3 Date: Wed, 30 Aug 2017 12:58:11 +0200
   4 Subject: x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature
   5
   6 From: Hans de Goede <hdegoede@redhat.com>
   7
   8 commit 594a30fb12424717a41c62323d2a8bf167dbccad upstream.
   9
  10 When booting 4.13 on a VirtualBox VM on a Skylake host the following
  11 error shows up in the logs:
  12
  13  [    0.000000] [Firmware Bug]: TSC_DEADLINE disabled due to Errata;
  14                 please update microcode to version: 0xb2 (or later)
  15
  16 This is caused by apic_check_deadline_errata() only checking CPU model
  17 and not the X86_FEATURE_TSC_DEADLINE_TIMER flag (which VirtualBox does
  18 NOT export to the guest), combined with VirtualBox not exporting the
  19 micro-code version to the guest.
  20
  21 This commit adds a check for X86_FEATURE_TSC_DEADLINE_TIMER to
  22 apic_check_deadline_errata(), silencing this error on VirtualBox VMs.
  23
  24 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  25 Acked-by: Thomas Gleixner <tglx@linutronix.de>
  26 Cc: Frank Mehnert <frank.mehnert@oracle.com>
  27 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  28 Cc: Michael Thayer <michael.thayer@oracle.com>
  29 Cc: Michal Necasek <michal.necasek@oracle.com>
  30 Cc: Peter Zijlstra <peterz@infradead.org>
  31 Fixes: bd9240a18e ("x86/apic: Add TSC_DEADLINE quirk due to errata")
  32 Link: http://lkml.kernel.org/r/20170830105811.27539-1-hdegoede@redhat.com
  33 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  34 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
  35 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  36
  37 ---
  38  arch/x86/kernel/apic/apic.c |    6 +++++-
  39  1 file changed, 5 insertions(+), 1 deletion(-)
  40
  41 --- a/arch/x86/kernel/apic/apic.c
  42 +++ b/arch/x86/kernel/apic/apic.c
  43 @@ -599,9 +599,13 @@ static const struct x86_cpu_id deadline_
  44
  45  static void apic_check_deadline_errata(void)
  46  {
  47 -       const struct x86_cpu_id *m = x86_match_cpu(deadline_match);
  48 +       const struct x86_cpu_id *m;
  49         u32 rev;
  50
  51 +       if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
  52 +               return;
  53 +
  54 +       m = x86_match_cpu(deadline_match);
  55         if (!m)
  56                 return;
  57