releases/4.14.112/x86-power-64-use-struct-desc_ptr-for-the-idt-in-stru.patch

   1 From 896f9da0c46953beafe93453bd07c497688e78f3 Mon Sep 17 00:00:00 2001
   2 From: Andy Lutomirski <luto@kernel.org>
   3 Date: Thu, 14 Dec 2017 13:19:05 -0800
   4 Subject: x86/power/64: Use struct desc_ptr for the IDT in struct saved_context
   5
   6 [ Upstream commit 090edbe23ff57940fca7f57d9165ce57a826bd7a ]
   7
   8 x86_64's saved_context nonsensically used separate idt_limit and
   9 idt_base fields and then cast &idt_limit to struct desc_ptr *.
  10
  11 This was correct (with -fno-strict-aliasing), but it's confusing,
  12 served no purpose, and required #ifdeffery. Simplify this by
  13 using struct desc_ptr directly.
  14
  15 No change in functionality.
  16
  17 Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
  18 Signed-off-by: Andy Lutomirski <luto@kernel.org>
  19 Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  20 Acked-by: Thomas Gleixner <tglx@linutronix.de>
  21 Cc: Borislav Petkov <bpetkov@suse.de>
  22 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  23 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  24 Cc: Pavel Machek <pavel@ucw.cz>
  25 Cc: Peter Zijlstra <peterz@infradead.org>
  26 Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
  27 Cc: Zhang Rui <rui.zhang@intel.com>
  28 Link: http://lkml.kernel.org/r/967909ce38d341b01d45eff53e278e2728a3a93a.1513286253.git.luto@kernel.org
  29 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  30 Signed-off-by: Sasha Levin <sashal@kernel.org>
  31 ---
  32  arch/x86/include/asm/suspend_64.h |  3 +--
  33  arch/x86/power/cpu.c              | 11 +----------
  34  2 files changed, 2 insertions(+), 12 deletions(-)
  35
  36 diff --git a/arch/x86/include/asm/suspend_64.h b/arch/x86/include/asm/suspend_64.h
  37 index 7306e911faee..600e9e0aea51 100644
  38 --- a/arch/x86/include/asm/suspend_64.h
  39 +++ b/arch/x86/include/asm/suspend_64.h
  40 @@ -30,8 +30,7 @@ struct saved_context {
  41         u16 gdt_pad; /* Unused */
  42         struct desc_ptr gdt_desc;
  43         u16 idt_pad;
  44 -       u16 idt_limit;
  45 -       unsigned long idt_base;
  46 +       struct desc_ptr idt;
  47         u16 ldt;
  48         u16 tss;
  49         unsigned long tr;
  50 diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
  51 index a51d2dfb57d1..cba2e2c3f89e 100644
  52 --- a/arch/x86/power/cpu.c
  53 +++ b/arch/x86/power/cpu.c
  54 @@ -82,12 +82,8 @@ static void __save_processor_state(struct saved_context *ctxt)
  55         /*
  56          * descriptor tables
  57          */
  58 -#ifdef CONFIG_X86_32
  59         store_idt(&ctxt->idt);
  60 -#else
  61 -/* CONFIG_X86_64 */
  62 -       store_idt((struct desc_ptr *)&ctxt->idt_limit);
  63 -#endif
  64 +
  65         /*
  66          * We save it here, but restore it only in the hibernate case.
  67          * For ACPI S3 resume, this is loaded via 'early_gdt_desc' in 64-bit
  68 @@ -221,12 +217,7 @@ static void notrace __restore_processor_state(struct saved_context *ctxt)
  69          * now restore the descriptor tables to their proper values
  70          * ltr is done i fix_processor_context().
  71          */
  72 -#ifdef CONFIG_X86_32
  73         load_idt(&ctxt->idt);
  74 -#else
  75 -/* CONFIG_X86_64 */
  76 -       load_idt((const struct desc_ptr *)&ctxt->idt_limit);
  77 -#endif
  78
  79  #ifdef CONFIG_X86_64
  80         /*
  81 --
  82 2.19.1
  83