lkml.org 
[lkml]   [2019]   [Jun]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH AUTOSEL 5.1 021/186] mm/cma_debug.c: fix the break condition in cma_maxchunk_get()
    Date
    From: Yue Hu <huyue2@yulong.com>

    [ Upstream commit f0fd50504a54f5548eb666dc16ddf8394e44e4b7 ]

    If not find zero bit in find_next_zero_bit(), it will return the size
    parameter passed in, so the start bit should be compared with bitmap_maxno
    rather than cma->count. Although getting maxchunk is working fine due to
    zero value of order_per_bit currently, the operation will be stuck if
    order_per_bit is set as non-zero.

    Link: http://lkml.kernel.org/r/20190319092734.276-1-zbestahu@gmail.com
    Signed-off-by: Yue Hu <huyue2@yulong.com>
    Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
    Cc: Michal Hocko <mhocko@suse.com>
    Cc: Joe Perches <joe@perches.com>
    Cc: David Rientjes <rientjes@google.com>
    Cc: Dmitry Safonov <d.safonov@partner.samsung.com>
    Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    mm/cma_debug.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff --git a/mm/cma_debug.c b/mm/cma_debug.c
    index 8d7b2fd522259..a7dd9e8e10d5d 100644
    --- a/mm/cma_debug.c
    +++ b/mm/cma_debug.c
    @@ -56,7 +56,7 @@ static int cma_maxchunk_get(void *data, u64 *val)
    mutex_lock(&cma->lock);
    for (;;) {
    start = find_next_zero_bit(cma->bitmap, bitmap_maxno, end);
    - if (start >= cma->count)
    + if (start >= bitmap_maxno)
    break;
    end = find_next_bit(cma->bitmap, bitmap_maxno, start);
    maxchunk = max(end - start, maxchunk);
    --
    2.20.1
    \
     
     \ /
      Last update: 2019-06-01 16:10    [W:8.084 / U:0.044 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site