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To: Liu Ye , akpm@linux-foundation.org, Liam.Howlett@oracle.com, lorenzo.stoakes@oracle.com, vbabka@suse.cz, jannh@google.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20250207060448.146606-1-liuye@kylinos.cn> Content-Language: en-US From: Dev Jain In-Reply-To: <20250207060448.146606-1-liuye@kylinos.cn> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 7C5E6A000D X-Stat-Signature: rf99b49ws713oqejkpnwfhe8rwta4gj7 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1738912201-689438 X-HE-Meta: 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 1tKV8GtG X4BpaIQ/zTfocLe49PJwNqpQavpJSGV+maGXZy3wsbXNnfwlot0X6d5IBymkijDznNRapfd+xUEVxVy93Es2X8/YeJo8QHTn+ulwCGeaZ6fZULUpGAZkyVE/w4hdKt2J6KcW2aNN4UirmYZTUZMFrfaz3Y5VR18RFirHguILi6TAA6vwmhO6BZ1RcbQc/9q3SLREh X-Bogosity: Ham, tests=bogofilter, spamicity=0.000035, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 07/02/25 11:34 am, Liu Ye wrote: > The condition in WARN_ON_ONCE(cpu_online(cpu)) should be !cpu_online(cpu) > to ensure the warning is triggered when the CPU is offline. > > Signed-off-by: Liu Ye > --- > mm/mlock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/mlock.c b/mm/mlock.c > index cde076fa7d5e..40acf7897917 100644 > --- a/mm/mlock.c > +++ b/mm/mlock.c > @@ -224,7 +224,7 @@ void mlock_drain_remote(int cpu) > { > struct folio_batch *fbatch; > > - WARN_ON_ONCE(cpu_online(cpu)); > + WARN_ON_ONCE(!cpu_online(cpu)); > fbatch = &per_cpu(mlock_fbatch.fbatch, cpu); > if (folio_batch_count(fbatch)) > mlock_folio_batch(fbatch); No idea about this code path but mlock_drain_remote() is called by page_alloc_cpu_dead() which expects an offlined CPU according to the comments.