diff options
author | Dave Airlie <airlied@redhat.com> | 2020-07-24 08:28:09 +1000 |
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committer | Dave Airlie <airlied@redhat.com> | 2020-07-24 08:48:05 +1000 |
commit | 41206a073ceebc517245677a19f52ba6379b33a9 (patch) | |
tree | 2fc35aac6abe32b99058ad55b0fc6e4d449d1056 /mm/compaction.c | |
parent | 206739119508d5ab4b42ab480ff61a7e6cd72d7c (diff) | |
parent | ba47d845d715a010f7b51f6f89bae32845e6acb7 (diff) |
Merge v5.8-rc6 into drm-next
I've got a silent conflict + two trees based on fixes to merge.
Fixes a silent merge with amdgpu
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'mm/compaction.c')
-rw-r--r-- | mm/compaction.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index fd988b7e5f2b..86375605faa9 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -2316,15 +2316,26 @@ static enum compact_result compact_zone_order(struct zone *zone, int order, .page = NULL, }; - current->capture_control = &capc; + /* + * Make sure the structs are really initialized before we expose the + * capture control, in case we are interrupted and the interrupt handler + * frees a page. + */ + barrier(); + WRITE_ONCE(current->capture_control, &capc); ret = compact_zone(&cc, &capc); VM_BUG_ON(!list_empty(&cc.freepages)); VM_BUG_ON(!list_empty(&cc.migratepages)); - *capture = capc.page; - current->capture_control = NULL; + /* + * Make sure we hide capture control first before we read the captured + * page pointer, otherwise an interrupt could free and capture a page + * and we would leak it. + */ + WRITE_ONCE(current->capture_control, NULL); + *capture = READ_ONCE(capc.page); return ret; } |