From: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> Subject: [PATCH] proc: fix kpage[count,flags] interfaces to account for ARCH_PFN_OFFSET ARCH_PFN_OFFSET gives us the first PFN number (i.e. on ARM Exynos4 platform it is equal to 262144) while max_pfn is only the total number of PFNs (i.e. on ARM Exynos4 Universal C210 board it is equal to 131072) so currently it is impossible to read page count/flags values on affected archs/platforms throught /proc/kpage[count,flags] interfaces. Fix it by making code aware of ARCH_PFN_OFFSET. [ For x86 the resulting code remains unchanged as ARCH_PFN_OFFSET is eual to 0. ] Cc: Matt Mackall <mpm@xxxxxxxxxxx> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> --- fs/proc/page.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) Index: b/fs/proc/page.c =================================================================== --- a/fs/proc/page.c 2012-05-31 15:45:27.887110216 +0200 +++ b/fs/proc/page.c 2012-05-31 16:33:37.455109659 +0200 @@ -31,7 +31,8 @@ static ssize_t kpagecount_read(struct fi u64 pcount; pfn = src / KPMSIZE; - count = min_t(size_t, count, (max_pfn * KPMSIZE) - src); + count = min_t(size_t, count, + ((ARCH_PFN_OFFSET + max_pfn) * KPMSIZE) - src); if (src & KPMMASK || count & KPMMASK) return -EINVAL; @@ -174,7 +175,8 @@ static ssize_t kpageflags_read(struct fi ssize_t ret = 0; pfn = src / KPMSIZE; - count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src); + count = min_t(unsigned long, count, + ((ARCH_PFN_OFFSET + max_pfn) * KPMSIZE) - src); if (src & KPMMASK || count & KPMMASK) return -EINVAL; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>