Commit-ID: 21cdb6b568435738cc0b303b2b3b82742396310c
Gitweb: http://git.kernel.org/tip/21cdb6b568435738cc0b303b2b3b82742396310c
Author: Matt Fleming <m...@codeblueprint.co.uk>
AuthorDate: Fri, 27 Nov 2015 21:09:30 +0000
Committer: Ingo Molnar <mi...@kernel.org>
CommitDate: Sun, 29 Nov 2015 09:15:42 +0100
x86/mm: Page align the '_end' symbol to avoid pfn conversion bugs
Ingo noted that if we can guarantee _end is aligned to PAGE_SIZE
we can automatically avoid bugs along the lines of,
size = _end - _text >> PAGE_SHIFT
which is missing a call to PFN_ALIGN(). The EFI mixed mode
contains this bug, for example.
_text is already aligned to PAGE_SIZE through the use of
LOAD_PHYSICAL_ADDR, and the BSS and BRK sections are explicitly
aligned in the linker script, so it makes sense to align _end to
match.
Reported-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Matt Fleming <m...@codeblueprint.co.uk>
Acked-by: Borislav Petkov <b...@suse.de>
Cc: Andy Lutomirski <l...@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheu...@linaro.org>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Brian Gerst <brge...@gmail.com>
Cc: Dave Hansen <dave.han...@intel.com>
Cc: Denys Vlasenko <dvlas...@redhat.com>
Cc: H. Peter Anvin <h...@zytor.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Toshi Kani <toshi.k...@hp.com>
Cc: linux-...@vger.kernel.org
Link:
http://lkml.kernel.org/r/1448658575-17029-2-git-send-email-m...@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
arch/x86/kernel/vmlinux.lds.S | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 74e4bf1..4f19942 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -325,6 +325,7 @@ SECTIONS
__brk_limit = .;
}
+ . = ALIGN(PAGE_SIZE);
_end = .;
STABS_DEBUG
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
