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b=OAv7URM4gS6KWb27UemNJmbekO9vk4EqLova3KvwicJypcAJgHj2snI3j/m3cFZ+1 5+deLzSDXgFrTErYM0HYxsPmmwZh7cpb7Fke0vFV0kVgKPj9T0wxobDw235Bqmine4 7fC5IrFq/OXVpOLFrAYq6Nsz25WDXQfD3sPAsAsM= Date: Tue, 17 Mar 2026 12:16:28 -0700 From: Andrew Morton To: Youngjun Park Cc: rafael@kernel.org, chrisl@kernel.org, kasong@tencent.com, pavel@kernel.org, shikemeng@huaweicloud.com, nphamcs@gmail.com, bhe@redhat.com, baohua@kernel.org, usama.arif@linux.dev, linux-pm@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v4 0/3] mm/swap, PM: hibernate: fix swapoff race and optimize swap Message-Id: <20260317121628.abc7f555ec78963b1d705fd9@linux-foundation.org> In-Reply-To: <20260317181318.2517015-1-youngjun.park@lge.com> References: <20260317181318.2517015-1-youngjun.park@lge.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: A72844000E X-Stat-Signature: j5omf99a8h534xafcjibo7uwgrpt718k X-Rspam-User: X-HE-Tag: 1773774990-77008 X-HE-Meta: U2FsdGVkX18TXDbj85NDrV+/oRvQ38PP8hpK9KXTbdlJoa7lyjq9eZwJR8HvBrg7LR2Va5DE8HhAVLf1golsJ788VJ5POUc/ZQ4yFqSLz2Rds38cGk3AvojVjeM4E6u7GymFK6FC9RVOvbO+lz0XIKQ84hFzv4yOksTuLQ54zlJqeVrK3lWfm0BLhWB62DcGvzPZwx+iu6tWsv3j92AFXZg8HP3ON7+WSgRiPDS7HUsJCJr5MwxSNHkHPXunGO6UcoRecAmFVagp44H1NILa9orwRWNzbmxhNvt+bPdD7T5isPaoE+8Y4/9JchWa2rFhqFxUaJVUXtnobQn1fUm7eGkgkQoX89ZGw3syud7UDUlAmxHQlojpc1CkPnHdNwnAeX3OALSHceN8zlGa6A3mW7bGLnf1kwqlvbXZFsSfrredTLVrnsZo0soa/qfogafDXFy+dOXJOtJu42BD6XnhFLVClWCzGiWvN1sXizAM/rbOx9XLFB8U7HEYBaI1shwrNsi7dmXd9VvvnbXCQPu+og8Q5U9gB1p3+ls6n2llSPmXatGV3FoSMBtecj5IroB2UfeWEz4Mko0Bd6Sa2DwzvPY1M5bQtZxHQ/48ssslUjq94Dcy79GIxxFQQLtO/DzimJi+o9ucZmOL4A9skUo93oxgbF2DkpAj/eRCqG7RQaH7xUXrkI/ADpZS8paWCz1TlzlShR8dRu8+eSS1HwteJSxMDokU++dTNy9GD7QTmMNsL4aUpOMbu69nGbXhPNPQLpmEVStLbYnC2jR/FcyfqKvztrvwe6r5Pz7aZutd+L6blXXXF4hGQxkmunWUVzi61jLt1WDX6+eRj/947pVLpq1h1cifVCJPjDZpUYmbSp6nR7ampQeDAXAYum/mvOucicUEIwTiDW1WjQc6bAScHCrt+Dgt+cxm+kfQ5cwTDv4qwTYS349Tk5WWGQD7QAZPzaATqxlnzdU5Uw1DAaJ f5qUHZw2 tUnQf1QMQWv40HwRwy7mexS5qAii88isZD0rmOgow1BUwPkRCzEVeXNFMJH9VjWby+VDe4YlDcFbXQJFnWewWm+ydYGx/3SVLADjODKagXWcyJ2hl0cZAELJc20+ekGJZAMdfbXxxqIZQa8gOzUalbYGVtHj+Q5FXSjnvl4w9omD2OfRstM09sVy4lNdHZ/XXlr9x+pfOZGx9wHhhOc6AJBqOL4AjW9HEeayqI75q2k7XYFKsC+AyszDCMGhvCwZ113Jv7juHS8Y5IdOew/MYnzOiow== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 18 Mar 2026 03:13:15 +0900 Youngjun Park wrote: > Currently, in the uswsusp path, only the swap type value is retrieved at > lookup time without holding a reference. If swapoff races after the type > is acquired, subsequent slot allocations operate on a stale swap device. Has this race been experienced or at least demonstrated? Or is this patchset derived from reading the code?