From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 96796CD37B5 for ; Mon, 11 May 2026 11:03:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=b3jDWeFYJ1RQc2SiIxMoyibpKT8QV19rCafUv4Y8bAE=; b=G07A8S4Yqf7L0+de9q9wzorrIx QK0uLMsMOuLlTMkcjW/Tu7dIK476UgpdvrXh3ZuQz4zE0GdcA/Ru6/wiIjNklWQZ0yoeLR2Rz66+n WbXEu5KE4S3XaCymeiBAYEffRFCRx7/HihdoGBA74AElnMRD0jvt7IVxYmTgPMATVFSA43WvoVsWz SawQlFUP32OYjbr6vrpkb9fNz0S25CCMlzHF3RVj95yK9q2SXuqKQdIhlzq1Y0eZNcTAlMQrGGwlK aDfp+4Py5s+W7KTK/LRMVJ51dcXc6x6rI885RE5Cn6BJN+gG6Ji0/p82S7Nl3OV5KYz2N86DM8Q4B FBE5Rjyg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wMOQI-0000000DDYB-2IY7; Mon, 11 May 2026 11:03:42 +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 1wMOQF-0000000DDXB-3Y6t for kexec@lists.infradead.org; Mon, 11 May 2026 11:03:41 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id D282F4195C; Mon, 11 May 2026 11:03:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2D9F3C2BCC9; Mon, 11 May 2026 11:03:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778497418; bh=TSs/vN70p0uwNlsWNWNw+qqsmsV+31QSlkIJ+FyA3Sk=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=aJNb3rG9eLyETc+c7dCYcxs8r8eBXcRmz0vVg8vuKZW2GoHqqFbVgBbrVrjq9Dysp WTN60mY3CklTkxWRllzkM7NyNddnqX0/Gbk76qbzyp8wTw6rWxy+W9pGwrqyNJQ7Jg tCYkIkvGdY83GQvSDv4miLSw7Aicx8OR2sy0Vo2GQIwntQXfT9n7YyhnZr2ECabXTs ZTyOI7GATKJNiaOtKWAk4JH1C8JvH3iusGCdCP7yPGxxOhaO/c1q0+4hm2DsPJoGGT B/UTvqYPlB1eCwgQ5D7QlRL4dWvxb6jGXRe4b6V7Wwv3UgBlPriRN2fX+5nm4PsXUS mwrDtr4syMDGg== From: Pratyush Yadav To: Pasha Tatashin Cc: rppt@kernel.org, sourabhjain@linux.ibm.com, jbouron@amazon.com, akpm@linux-foundation.org, linux-mm@kvack.org, bhe@redhat.com, linux-kernel@vger.kernel.org, dan.carpenter@linaro.org, rafael.j.wysocki@intel.com, piliu@redhat.com, kexec@lists.infradead.org, pratyush@kernel.org, graf@amazon.com, changyuanl@google.com, mario.limonciello@amd.com Subject: Re: [PATCH v2 3/3] liveupdate: block outgoing session mutations In-Reply-To: <20260506182039.2623553-8-pasha.tatashin@soleen.com> (Pasha Tatashin's message of "Wed, 6 May 2026 14:20:43 -0400") References: <20260506182039.2623553-5-pasha.tatashin@soleen.com> <20260506182039.2623553-8-pasha.tatashin@soleen.com> Date: Mon, 11 May 2026 13:03:34 +0200 Message-ID: <2vxzv7cucint.fsf@kernel.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260511_040340_044191_FCD6C7EE X-CRM114-Status: UNSURE ( 9.13 ) X-CRM114-Notice: Please train this message. X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Wed, May 06 2026, Pasha Tatashin wrote: > During the reboot() syscall, user processes may still be running > concurrently and attempting to mutate sessions (e.g., adding files or > closing sessions). To prevent this, hold the session header's rwsem and > each session's mutex indefinitely on successful serialization. > > If serialization succeeds, these locks will never be released as the > system transitions to the new kernel, effectively blocking any > concurrent task attempting to modify or release a session. If > liveupdate_reboot() fails, the locks are released in the error path, > allowing normal operation to resume. > > Fixes: 0153094d03df ("liveupdate: luo_session: add sessions support") > Reported-by: Oskar Gerlicz Kowalczuk > Signed-off-by: Pasha Tatashin Reviewed-by: Pratyush Yadav (Google) [...] -- Regards, Pratyush Yadav