patches/kernel/0230-UBUNTU-SAUCE-only-attempt-to-use-PCID-in-64-bit-buil.patch

   1 From 3642d7fb8bcab15ab1f82531f8120e22181cd7da Mon Sep 17 00:00:00 2001
   2 From: Andy Whitcroft <apw@canonical.com>
   3 Date: Wed, 20 Dec 2017 13:33:50 +0000
   4 Subject: [PATCH 230/241] UBUNTU: SAUCE: only attempt to use PCID in 64 bit
   5  builds
   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 [apw@canonical.com: need to review if this is still needed with the
  13 latest patches.]
  14 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  15 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  16 (cherry picked from commit babace1d1ac19075498675cd787500cfa24d2b55)
  17 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  18 ---
  19  arch/x86/kernel/smpboot.c | 2 +-
  20  1 file changed, 1 insertion(+), 1 deletion(-)
  21
  22 diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
  23 index 6ad8391b9866..398e8324fea4 100644
  24 --- a/arch/x86/kernel/smpboot.c
  25 +++ b/arch/x86/kernel/smpboot.c
  26 @@ -222,7 +222,7 @@ static void notrace start_secondary(void *unused)
  27          * before cpu_init(), SMP booting is too fragile that we want to
  28          * limit the things done here to the most necessary things.
  29          */
  30 -       if (boot_cpu_has(X86_FEATURE_PCID))
  31 +       if (IS_ENABLED(CONFIG_X86_64) && boot_cpu_has(X86_FEATURE_PCID))
  32                 __write_cr4(__read_cr4() | X86_CR4_PCIDE);
  33         cpu_init();
  34         x86_cpuinit.early_percpu_clock_init();
  35 --
  36 2.14.2
  37