[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20160413075417.GA14356@dhcp22.suse.cz>
Date: Wed, 13 Apr 2016 09:54:17 +0200
From: Michal Hocko <mhocko@...nel.org>
To: Anshuman Khandual <khandual@...ux.vnet.ibm.com>
Cc: linux-mm@...ck.org, linux-kernel@...r.kernel.org,
linuxppc-dev@...ts.ozlabs.org, hughd@...gle.com,
kirill@...temov.name, n-horiguchi@...jp.nec.com,
akpm@...ux-foundation.org, mgorman@...hsingularity.net,
dave.hansen@...el.com, aneesh.kumar@...ux.vnet.ibm.com,
mpe@...erman.id.au
Subject: Re: [PATCH 01/10] mm/mmap: Replace SHM_HUGE_MASK with MAP_HUGE_MASK
inside mmap_pgoff
On Thu 07-04-16 11:07:35, Anshuman Khandual wrote:
> The commit 091d0d55b286 ("shm: fix null pointer deref when userspace
> specifies invalid hugepage size") had replaced MAP_HUGE_MASK with
> SHM_HUGE_MASK. Though both of them contain the same numeric value of
> 0x3f, MAP_HUGE_MASK flag sounds more appropriate than the other one
> in the context. Hence change it back.
Yes, SHM_HUGE_MASK mixing with MAP_HUGE_SHIFT is not only misleading
it might bite us later should any of the two change.
>
> Signed-off-by: Anshuman Khandual <khandual@...ux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@...e.com>
> ---
> mm/mmap.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index bd2e1a53..7d730a4 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1315,7 +1315,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
> struct user_struct *user = NULL;
> struct hstate *hs;
>
> - hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & SHM_HUGE_MASK);
> + hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
> if (!hs)
> return -EINVAL;
>
> --
> 2.1.0
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@...ck.org. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"dont@...ck.org"> email@...ck.org </a>
--
Michal Hocko
SUSE Labs
Powered by blists - more mailing lists