From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B497960A2613 for ; Thu, 22 Oct 2026 02:04:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=2V0wusie; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=O+oP8EBL DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Reply-To:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Date: Content-Transfer-Encoding:Content-Type:References:In-Reply-To:To:Subject:From :Message-ID:Cc:MIME-Version:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=3dXhVJAvltFbXjWv/MwSJt3IG8Jdyzq4Meb3s8xafDo=; b=2V0wusierJePoEZW5kF91t62DJ 3L3hTwCQ7mspWzKo+XRTZswXI9e9/Cz5cg6geXsVVolOn8YK2wBv23OEHMi6W7a562CFn9v8iQh3q 9NAgWTGahLh3qcsRV+hcwIx+f/T3ex0ckeeHX2MJP6Hw7kvXnK6QzBM82pb4wae9c0UmS9y2WeuOJ bwERXJcGBtwDYw9FivJj1MY9MYZVw4xQTb4NKYHaWhUMo1xuCX98EgAPN7Kw6nKGGHX9wuThzUOhY HwWn9rFZ+iXFvSWMwSzzhYtOb1inBm1Bm0O5xO9PYCnjQ0IF0j+Ml1feZumRqHyEtHlqqyQVPF32x 2LiidONA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xJiAW-0000000DAxI-2drj; Thu, 22 Oct 2026 02:04:36 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xJiAV-0000000DAx3-0LfW for kexec@lists.infradead.org; Thu, 22 Oct 2026 02:04:35 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 8160644829; Thu, 22 Oct 2026 02:04:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE5641F000C1; Thu, 22 Oct 2026 02:04:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792634674; bh=3dXhVJAvltFbXjWv/MwSJt3IG8Jdyzq4Meb3s8xafDo=; h=From:Subject:Reply-To:To:In-Reply-To:References:Date; b=O+oP8EBL4nPp4Myy3kn1mYXlWVPaJOEV7S5nnd+BtKA+ZNpyZKlTkGjyfclEMPuvY ABqRyWNlndPvvjXM+W7NfRWfnSURe9lmC3NoWrRW0YXIQ6Q44O4J6/E3VtvcxwZp2y PBsLB4hy1yyyHk1c/8X7xy/K6AlZnZB04wTnwCrni+sCZxhIrGXRrLLqJZwjD8U13l /UlyipYx6LWK7kRevKe7m5FhtIBkuYKdVQ0AYo4ZSwqug3luzNW0WUomRlhRnqJpyd 6wCp3ulRh5jyi437E5coKpdLOidoMqMBrR7OrHoTeR0VxhYKFI8hOZIcKarcZ7hotc WrwYie5y0L8+w== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 1/2] liveupdate: Add LIVEUPDATE_SESSION_FREEZE ioctl to freeze sessions early To: "Pasha Tatashin" , rppt@kernel.org, shuah@kernel.org, akpm@linux-foundation.org, vipinsh@google.com, dmatlack@google.com, kexec@lists.infradead.org, pratyush@kernel.org, graf@amazon.com In-Reply-To: <20261022015844.2795816-2-pasha.tatashin@soleen.com> References: <20261022015844.2795816-1-pasha.tatashin@soleen.com> <20261022015844.2795816-2-pasha.tatashin@soleen.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 22 Oct 2026 02:04:33 +0000 X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "kexec" X-Spam-Status: No, score=-10.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: > Currently, LUO sessions are frozen automatically only inside the > reboot(LINUX_REBOOT_CMD_KEXEC) pathway, where luo_session_serialize() > iterates through all outgoing sessions under global write locks and > freezes them serially during shutdown. Allowing userspace to decide when > to freeze a session once it is done with it (and to freeze multiple > sessions in parallel, since luo_session_freeze() only acquires the > per-session mutex) avoids postponing this work to kexec shutdown and > reduces blackout time. >=20 > Introduce LIVEUPDATE_SESSION_FREEZE on session file descriptors to freeze > a session early. The ioctl runs .freeze() across all preserved files in t= he > session and serializes their metadata. Once frozen, no additional files c= an > be added to the session, and subsequent freeze calls return -EBUSY. Freeze > is only valid on outgoing sessions and returns -EINVAL on incoming ones. >=20 > During kexec, sessions that were already frozen early are skipped, while > sessions that did not invoke this ioctl auto-freeze as before. If an > early-frozen session is released before kexec, its files are rolled back > via .unfreeze() before being unpreserved. >=20 > Reviewed-by: Pratyush Yadav > Signed-off-by: Pasha Tatashin Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261022015844.2795= 816-1-pasha.tatashin@soleen.com?part=3D1