patches/kernel/0232-UBUNTU-SAUCE-only-attempt-to-use-PCID-in-64-bit-buil.patch

   1 From 0000000000000000000000000000000000000000 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] UBUNTU: SAUCE: only attempt to use PCID in 64 bit builds
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 CVE-2017-5754
  10
  11 [apw@canonical.com: need to review if this is still needed with the
  12 latest patches.]
  13 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  14 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  15 (cherry picked from commit babace1d1ac19075498675cd787500cfa24d2b55)
  16 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  17 ---
  18  arch/x86/kernel/smpboot.c | 2 +-
  19  1 file changed, 1 insertion(+), 1 deletion(-)
  20
  21 diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
  22 index 6ad8391b9866..398e8324fea4 100644
  23 --- a/arch/x86/kernel/smpboot.c
  24 +++ b/arch/x86/kernel/smpboot.c
  25 @@ -222,7 +222,7 @@ static void notrace start_secondary(void *unused)
  26          * before cpu_init(), SMP booting is too fragile that we want to
  27          * limit the things done here to the most necessary things.
  28          */
  29 -       if (boot_cpu_has(X86_FEATURE_PCID))
  30 +       if (IS_ENABLED(CONFIG_X86_64) && boot_cpu_has(X86_FEATURE_PCID))
  31                 __write_cr4(__read_cr4() | X86_CR4_PCIDE);
  32         cpu_init();
  33         x86_cpuinit.early_percpu_clock_init();
  34 --
  35 2.14.2
  36