Commit e3df4c6e authored Feb 01, 2019 by Michal Hocko Committed by Linus Torvalds Feb 01, 2019

mm, memory_hotplug: __offline_pages fix wrong locking

Jan has noticed that we do double unlock on some failure paths when
offlining a page range.  This is indeed the case when
test_pages_in_a_zone respp.  start_isolate_page_range fail.  This was an
omission when forward porting the debugging patch from an older kernel.

Fix the issue by dropping mem_hotplug_done from the failure condition
and keeping the single unlock in the catch all failure path.

Link: http://lkml.kernel.org/r/20190115120307.22768-1-mhocko@kernel.org


Fixes: 79605093 ("mm, memory_hotplug: print reason for the offlining failure")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Tested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 6376360e

mm/memory_hotplug.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -1570,7 +1570,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
		we assume this for now. .*/
		if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start,
		&valid_end)) {
		mem_hotplug_done();
		ret = -EINVAL;
		reason = "multizone range";
		goto failed_removal;
		@@ -1585,7 +1584,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
		MIGRATE_MOVABLE,
		SKIP_HWPOISON \| REPORT_FAILURE);
		if (ret) {
		mem_hotplug_done();
		reason = "failure to isolate range";
		goto failed_removal;
		}

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