patches/kernel/0064-x86-unwind-Make-CONFIG_UNWINDER_ORC-y-the-default-in.patch

   1 From a8ec58033a185db5d8c180d3508d34b8ae3a1c89 Mon Sep 17 00:00:00 2001
   2 From: Josh Poimboeuf <jpoimboe@redhat.com>
   3 Date: Fri, 13 Oct 2017 15:02:01 -0500
   4 Subject: [PATCH 064/241] x86/unwind: Make CONFIG_UNWINDER_ORC=y the default in
   5  kconfig for 64-bit
   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 The ORC unwinder has been stable in testing so far.  Give it much wider
  13 testing by making it the default in kconfig for x86_64.  It's not yet
  14 supported for 32-bit, so leave frame pointers as the default there.
  15
  16 Suggested-by: Ingo Molnar <mingo@kernel.org>
  17 Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
  18 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  19 Cc: Peter Zijlstra <peterz@infradead.org>
  20 Cc: Thomas Gleixner <tglx@linutronix.de>
  21 Link: http://lkml.kernel.org/r/9b1237bbe7244ed9cdf8db2dcb1253e37e1c341e.1507924831.git.jpoimboe@redhat.com
  22 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  23 (cherry picked from commit fc72ae40e30327aa24eb88a24b9c7058f938bd36)
  24 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  25 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  26 (cherry picked from commit aff8d5169f46ae6ac0eb26a5ba745aaf9afa0704)
  27 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  28 ---
  29  arch/x86/Kconfig.debug | 33 +++++++++++++++++----------------
  30  1 file changed, 17 insertions(+), 16 deletions(-)
  31
  32 diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
  33 index 5435a943f894..7d88e9878a75 100644
  34 --- a/arch/x86/Kconfig.debug
  35 +++ b/arch/x86/Kconfig.debug
  36 @@ -358,27 +358,13 @@ config PUNIT_ATOM_DEBUG
  37
  38  choice
  39         prompt "Choose kernel unwinder"
  40 -       default UNWINDER_FRAME_POINTER
  41 +       default UNWINDER_ORC if X86_64
  42 +       default UNWINDER_FRAME_POINTER if X86_32
  43         ---help---
  44           This determines which method will be used for unwinding kernel stack
  45           traces for panics, oopses, bugs, warnings, perf, /proc/<pid>/stack,
  46           livepatch, lockdep, and more.
  47
  48 -config UNWINDER_FRAME_POINTER
  49 -       bool "Frame pointer unwinder"
  50 -       select FRAME_POINTER
  51 -       ---help---
  52 -         This option enables the frame pointer unwinder for unwinding kernel
  53 -         stack traces.
  54 -
  55 -         The unwinder itself is fast and it uses less RAM than the ORC
  56 -         unwinder, but the kernel text size will grow by ~3% and the kernel's
  57 -         overall performance will degrade by roughly 5-10%.
  58 -
  59 -         This option is recommended if you want to use the livepatch
  60 -         consistency model, as this is currently the only way to get a
  61 -         reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE).
  62 -
  63  config UNWINDER_ORC
  64         bool "ORC unwinder"
  65         depends on X86_64
  66 @@ -396,6 +382,21 @@ config UNWINDER_ORC
  67           Enabling this option will increase the kernel's runtime memory usage
  68           by roughly 2-4MB, depending on your kernel config.
  69
  70 +config UNWINDER_FRAME_POINTER
  71 +       bool "Frame pointer unwinder"
  72 +       select FRAME_POINTER
  73 +       ---help---
  74 +         This option enables the frame pointer unwinder for unwinding kernel
  75 +         stack traces.
  76 +
  77 +         The unwinder itself is fast and it uses less RAM than the ORC
  78 +         unwinder, but the kernel text size will grow by ~3% and the kernel's
  79 +         overall performance will degrade by roughly 5-10%.
  80 +
  81 +         This option is recommended if you want to use the livepatch
  82 +         consistency model, as this is currently the only way to get a
  83 +         reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE).
  84 +
  85  config UNWINDER_GUESS
  86         bool "Guess unwinder"
  87         depends on EXPERT
  88 --
  89 2.14.2
  90