From 35545f0ccbd5a8ee01ba6824a2c68c0dcb787180 Mon Sep 17 00:00:00 2001
From: Mark Rutland <mark.rutland@arm.com>
Date: Fri, 5 Dec 2014 12:34:54 +0000
Subject: [PATCH] arm64: mm: dump: fix shift warning
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When building with 48-bit VAs, it's possible to get the following
warning when building the arm64 page table dumping code:
arch/arm64/mm/dump.c: In function ‘walk_pgd’:
arch/arm64/mm/dump.c:266:2: warning: right shift count >= width of type
pgd_t *pgd = pgd_offset(mm, 0);
^
As pgd_offset is a macro and the second argument is not cast to any
particular type, the zero will be given integer type by the compiler.
As pgd_offset passes the pargument to pgd_index, we then try to shift
the 32-bit integer by at least 39 bits (for 4k pages).
Elsewhere the pgd_offset is passed a second argument of unsigned long
type, so let's do the same here by passing '0UL' rather than '0'.
Cc: Kees Cook <keescook@chromium.org>
Acked-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/mm/dump.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c
index bf69601be5465..a546776264c4e 100644
--- a/arch/arm64/mm/dump.c
+++ b/arch/arm64/mm/dump.c
@@ -272,7 +272,7 @@ static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start)
static void walk_pgd(struct pg_state *st, struct mm_struct *mm, unsigned long start)
{
- pgd_t *pgd = pgd_offset(mm, 0);
+ pgd_t *pgd = pgd_offset(mm, 0UL);
unsigned i;
unsigned long addr;
--
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