From c9690998ef48ffefeccb91c70a7739eebdea57f9 Mon Sep 17 00:00:00 2001 From: Andreas Herrmann Date: Mon, 8 Jun 2009 19:09:39 +0200 Subject: [PATCH] x86: memtest: remove 64-bit division Using gcc 3.3.5 a "make allmodconfig" + "CONFIG_KVM=n" triggers a build error: arch/x86/mm/built-in.o(.init.text+0x43f7): In function `__change_page_attr': arch/x86/mm/pageattr.c:114: undefined reference to `__udivdi3' make: *** [.tmp_vmlinux1] Error 1 The culprit turned out to be a division in arch/x86/mm/memtest.c For more info see this thread: http://marc.info/?l=linux-kernel&m=124416232620683 The patch entirely removes the division that caused the build error. [ Impact: build fix with certain GCC versions ] Reported-by: Tetsuo Handa Signed-off-by: Andreas Herrmann Cc: Yinghai Lu Cc: xiyou.wangcong@gmail.com Cc: Andrew Morton Cc: LKML-Reference: <20090608170939.GB12431@alberich.amd.com> Signed-off-by: Ingo Molnar --- arch/x86/mm/memtest.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/mm/memtest.c b/arch/x86/mm/memtest.c index 605c8be06217..c0bedcd10f97 100644 --- a/arch/x86/mm/memtest.c +++ b/arch/x86/mm/memtest.c @@ -40,23 +40,23 @@ static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad) static void __init memtest(u64 pattern, u64 start_phys, u64 size) { - u64 i, count; - u64 *start; + u64 *p; + void *start, *end; u64 start_bad, last_bad; u64 start_phys_aligned; size_t incr; incr = sizeof(pattern); start_phys_aligned = ALIGN(start_phys, incr); - count = (size - (start_phys_aligned - start_phys))/incr; start = __va(start_phys_aligned); + end = start + size - (start_phys_aligned - start_phys); start_bad = 0; last_bad = 0; - for (i = 0; i < count; i++) - start[i] = pattern; - for (i = 0; i < count; i++, start++, start_phys_aligned += incr) { - if (*start == pattern) + for (p = start; p < end; p++) + *p = pattern; + for (p = start; p < end; p++, start_phys_aligned += incr) { + if (*p == pattern) continue; if (start_phys_aligned == last_bad + incr) { last_bad += incr; -- 2.20.1