[tip:x86/apic] x86/idt: Move 32-bit idt_descr to C code

tip-bot for Thomas Gleixner
2017-08-29T11:21:22Z

Commit-ID: 16bc18d895cee95f12bd722e5a3016676dfcf084
Gitweb: http://git.kernel.org/tip/16bc18d895cee95f12bd722e5a3016676dfcf084
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Mon, 28 Aug 2017 08:47:44 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 29 Aug 2017 12:07:26 +0200

x86/idt: Move 32-bit idt_descr to C code

32-bit kernels have the idt_descr defined in the low level assembly entry code,
but there is no good reason for that.

Move it into the C file and use the 64-bit version of it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.445862201@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/kernel/head_32.S | 6 ------
arch/x86/kernel/idt.c | 10 +++++-----
2 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 29da959..ce8c6ed 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -622,7 +622,6 @@ int_msg:

.data
.globl boot_gdt_descr
-.globl idt_descr

ALIGN
# early boot GDT descriptor (must use 1:1 address mapping)
@@ -631,11 +630,6 @@ boot_gdt_descr:
.word __BOOT_DS+7
.long boot_gdt - __PAGE_OFFSET

- .word 0 # 32-bit align idt_desc.address
-idt_descr:
- .word IDT_ENTRIES*8-1 # idt contains 256 entries
- .long idt_table
-
# boot GDT descriptor (later on used by CPU#0):
.word 0 # 32 bit align gdt_desc.address
ENTRY(early_gdt_descr)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 3d19cad..86e5912 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -10,15 +10,15 @@
/* Must be page-aligned because the real IDT is used in a fixmap. */
gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss;

-#ifdef CONFIG_X86_64
-/* No need to be aligned, but done to keep all IDTs defined the same way. */
-gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss;
-
struct desc_ptr idt_descr __ro_after_init = {
- .size = IDT_ENTRIES * 16 - 1,
+ .size = (IDT_ENTRIES * 2 * sizeof(unsigned long)) - 1,
.address = (unsigned long) idt_table,
};

+#ifdef CONFIG_X86_64
+/* No need to be aligned, but done to keep all IDTs defined the same way. */
+gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss;
+
const struct desc_ptr debug_idt_descr = {
.size = IDT_ENTRIES * 16 - 1,
.address = (unsigned long) debug_idt_table,