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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230807063945.911582-1-apopple@nvidia.com> X-Stat-Signature: ahypzh9qz7nyafq9hjmejdq8yndqjqed X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 219B11A0013 X-Rspam-User: X-HE-Tag: 1691397579-979507 X-HE-Meta: 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 6QX69Yc6 kDrAacPqZ/qL/UFguTtFS3mZdIOCJSBVaYV6cOG3r1Wggk02N5aIjvKAYZMKUkDvjg99OwjvBVLC41crYDtB0JI36AFnGdWKMI8NFXUBXbnteNxyfAdPdt1AiNew3yWkfjXWeBghbvZxV62r1P8Y8hry9vdAIzDDdjiPr/FIup3eSYoo= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 07-08-23 16:39:44, Alistair Popple wrote: > When a page fails to migrate move_pages() returns the error code in a > per-page array of status values. The function call itself is also > supposed to return a summary error code indicating that a failure > occurred. > > This doesn't always happen. Instead success can be returned even > though some pages failed to migrate. This is due to incorrectly > returning the error code from store_status() rather than the code from > add_page_for_migration. Fix this by only returning an error from > store_status() if the store actually failed. Error reporting by this syscall has been really far from straightforward. Please read through a49bd4d71637 and the section "On a side note". Is there any specific reason you are trying to address this now or is this motivated by the code inspection? > Signed-off-by: Alistair Popple > Fixes: a49bd4d71637 ("mm, numa: rework do_pages_move") > --- > mm/migrate.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/mm/migrate.c b/mm/migrate.c > index 24baad2571e3..bb3a37245e13 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -2222,7 +2222,9 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, > * If the page is already on the target node (!err), store the > * node, otherwise, store the err. > */ > - err = store_status(status, i, err ? : current_node, 1); > + err1 = store_status(status, i, err ? : current_node, 1); > + if (err1) > + err = err1; > if (err) > goto out_flush; > > -- > 2.39.2 -- Michal Hocko SUSE Labs