From: Nick Desaulniers <nick.desaulniers@gmail.com>
Cc: akpm@linux-foundation.org, hannes@cmpxchg.org,
mgorman@techsingularity.net, mhocko@suse.com, vbabka@suse.cz,
minchan@kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
Nick Desaulniers <nick.desaulniers@gmail.com>
Subject: [PATCH] mm/vmscan: fix unsequenced modification and access warning
Date: Tue, 9 May 2017 23:53:28 -0700 [thread overview]
Message-ID: <20170510065328.9215-1-nick.desaulniers@gmail.com> (raw)
Clang flags this file with the -Wunsequenced error that GCC does not
have.
unsequenced modification and access to 'gfp_mask'
It seems that gfp_mask is both read and written without a sequence point
in between, which is undefined behavior.
Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
---
mm/vmscan.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4e7ed65842af..74785908822c 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2958,7 +2958,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
unsigned long nr_reclaimed;
struct scan_control sc = {
.nr_to_reclaim = SWAP_CLUSTER_MAX,
- .gfp_mask = (gfp_mask = current_gfp_context(gfp_mask)),
+ .gfp_mask = current_gfp_context(gfp_mask),
.reclaim_idx = gfp_zone(gfp_mask),
.order = order,
.nodemask = nodemask,
@@ -2968,6 +2968,8 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
.may_swap = 1,
};
+ gfp_mask = sc.gfp_mask;
+
/*
* Do not enter reclaim if fatal signal was delivered while throttled.
* 1 is returned so that the page allocator does not OOM kill at this
--
2.11.0
--
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next reply other threads:[~2017-05-10 6:54 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-05-10 6:53 Nick Desaulniers [this message]
2017-05-10 7:15 ` [PATCH] mm/vmscan: fix unsequenced modification and access warning Michal Hocko
2017-05-10 8:27 ` [Patch v2] " Nick Desaulniers
2017-05-10 8:38 ` Michal Hocko
2017-05-16 8:27 ` Michal Hocko
2017-05-17 3:01 ` Nick Desaulniers
2017-05-26 4:43 ` Nick Desaulniers
2017-05-31 15:21 ` Michal Hocko
2017-05-10 8:46 ` [PATCH] " Nick Desaulniers
2017-05-10 9:25 ` Michal Hocko
2017-05-10 15:40 ` [Patch v3] " Nick Desaulniers
2018-03-21 21:37 ` [PATCH] " Nick Desaulniers
2018-03-22 9:50 ` Michal Hocko
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