Subject: [merged] mm-fix-negative-left-shift-count-when-page_shift-20.patch removed from -mm tree To: uulinux@xxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Thu, 12 Sep 2013 12:42:33 -0700 The patch titled Subject: mm: fix negative left shift count when PAGE_SHIFT > 20 has been removed from the -mm tree. Its filename was mm-fix-negative-left-shift-count-when-page_shift-20.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Jerry Zhou <uulinux@xxxxxxxxx> Subject: mm: fix negative left shift count when PAGE_SHIFT > 20 When PAGE_SHIFT > 20, the result of "20 - PAGE_SHIFT" is negative. The previous calculating here will generate an unexpected result. In addition, if PAGE_SIZE >= 1MB, The memory size of "numentries" was already integral multiple of 1MB. Signed-off-by: Jerry Zhou <uulinux@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff -puN mm/page_alloc.c~mm-fix-negative-left-shift-count-when-page_shift-20 mm/page_alloc.c --- a/mm/page_alloc.c~mm-fix-negative-left-shift-count-when-page_shift-20 +++ a/mm/page_alloc.c @@ -5745,9 +5745,10 @@ void *__init alloc_large_system_hash(con if (!numentries) { /* round applicable memory size up to nearest megabyte */ numentries = nr_kernel_pages; - numentries += (1UL << (20 - PAGE_SHIFT)) - 1; - numentries >>= 20 - PAGE_SHIFT; - numentries <<= 20 - PAGE_SHIFT; + + /* It isn't necessary when PAGE_SIZE >= 1MB */ + if (PAGE_SHIFT < 20) + numentries = round_up(numentries, (1<<20)/PAGE_SIZE); /* limit to 1 bucket per 2^scale bytes of low memory */ if (scale > PAGE_SHIFT) _ Patches currently in -mm which might be from uulinux@xxxxxxxxx are origin.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html