Patch "vmlinux.lds: account for destructor sections" has been added to the 4.6-stable tree
From: <gregkh@linuxfoundation.org>
Date: 2016-08-02 07:07:21
This is a note to let you know that I've just added the patch titled
vmlinux.lds: account for destructor sections
to the 4.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
vmlinux.lds-account-for-destructor-sections.patch
and it can be found in the queue-4.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let [off-list ref] know about it.
From e41f501d391265ff568f3e49d6128cc30856a36f Mon Sep 17 00:00:00 2001
From: Dmitry Vyukov <dvyukov@google.com>
Date: Thu, 14 Jul 2016 12:07:29 -0700
Subject: vmlinux.lds: account for destructor sections
From: Dmitry Vyukov <dvyukov@google.com>
commit e41f501d391265ff568f3e49d6128cc30856a36f upstream.
If CONFIG_KASAN is enabled and gcc is configured with
--disable-initfini-array and/or gold linker is used, gcc emits
.ctors/.dtors and .text.startup/.text.exit sections instead of
.init_array/.fini_array. .dtors section is not explicitly accounted in
the linker script and messes vvar/percpu layout.
We want:
ffffffff822bfd80 D _edata
ffffffff822c0000 D __vvar_beginning_hack
ffffffff822c0000 A __vvar_page
ffffffff822c0080 0000000000000098 D vsyscall_gtod_data
ffffffff822c1000 A __init_begin
ffffffff822c1000 D init_per_cpu__irq_stack_union
ffffffff822c1000 A __per_cpu_load
ffffffff822d3000 D init_per_cpu__gdt_page
We got:
ffffffff8279a600 D _edata
ffffffff8279b000 A __vvar_page
ffffffff8279c000 A __init_begin
ffffffff8279c000 D init_per_cpu__irq_stack_union
ffffffff8279c000 A __per_cpu_load
ffffffff8279e000 D __vvar_beginning_hack
ffffffff8279e080 0000000000000098 D vsyscall_gtod_data
ffffffff827ae000 D init_per_cpu__gdt_page
This happens because __vvar_page and .vvar get different addresses in
arch/x86/kernel/vmlinux.lds.S:
. = ALIGN(PAGE_SIZE);
__vvar_page = .;
.vvar : AT(ADDR(.vvar) - LOAD_OFFSET) {
/* work around gold bug 13023 */
__vvar_beginning_hack = .;
Discard .dtors/.fini_array/.text.exit, since we don't call dtors.
Merge .text.startup into init text.
Link: http://lkml.kernel.org/r/1467386363-120030-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Ryabinin <redacted>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/asm-generic/vmlinux.lds.h | 4 ++++
1 file changed, 4 insertions(+)
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h@@ -540,15 +540,19 @@ #define INIT_TEXT \ *(.init.text) \ + *(.text.startup) \ MEM_DISCARD(init.text) #define EXIT_DATA \ *(.exit.data) \ + *(.fini_array) \ + *(.dtors) \ MEM_DISCARD(exit.data) \ MEM_DISCARD(exit.rodata) #define EXIT_TEXT \ *(.exit.text) \ + *(.text.exit) \ MEM_DISCARD(exit.text) #define EXIT_CALL \
Patches currently in stable-queue which might be from dvyukov@google.com are queue-4.6/mm-thp-refix-false-positive-bug-in-page_move_anon_rmap.patch queue-4.6/vmlinux.lds-account-for-destructor-sections.patch queue-4.6/radix-tree-fix-radix_tree_iter_retry-for-tagged-iterators.patch