From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E19E8606A31A for ; Fri, 23 Oct 2026 14:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=xenproject.org header.i=@xenproject.org header.a=rsa-sha256 header.s=20200302mail header.b=y2AzbLjE Received: from list by lists.xenproject.org with outflank-mailman.1459324.1671292 (Exim 4.92) (envelope-from ) id 1xKFrR-0007iG-Ot; Fri, 23 Oct 2026 14:03:09 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 1459324.1671292; Fri, 23 Oct 2026 14:03:09 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1xKFrR-0007i9-MF; Fri, 23 Oct 2026 14:03:09 +0000 Received: by outflank-mailman (input) for mailman id 1459324; Fri, 23 Oct 2026 14:03:08 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1xKFrQ-0007hz-P7 for xen-devel@lists.xenproject.org; Fri, 23 Oct 2026 14:03:08 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.98.2) (envelope-from ) id 1xKFrQ-00000009CyB-2vzx; Fri, 23 Oct 2026 14:03:08 +0000 Received: from 224.pool85-54-217.dynamic.orange.es ([85.54.217.224] helo=localhost) by xenbits.xenproject.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1xKFrQ-0000000Daqu-0yiT; Fri, 23 Oct 2026 14:03:08 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Post: List-Help: List-Subscribe: , Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xenproject.org; s=20200302mail; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date; bh=Wc3tn8C8x90b0BbNhFnMcCsKHf7Q9nHWOBW+BOOCRJQ=; b=y2AzbLjEQInr/OFjy7S7YAm/HM i9XSN6Y0xDserYwO88O8/c+nLPazKSWhr98StlqK1W99qST1ND6sbTUkDw91seZ+6v0quurJ3fDg5 l9zkHDVvymBYsT46fZs3NByBkVodW6zZpXaSkiguoaV1nExrNIDzG4fJnEMyf0hb/bkY=; Date: Fri, 23 Oct 2026 16:03:05 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: xen-devel@lists.xenproject.org Cc: Jan Beulich , Andrew Cooper , Teddy Astie , Anthony PERARD , Michal Orzel , Julien Grall , Stefano Stabellini Subject: Re: [PATCH] xen/vcpu: ensure no write when runstate handler is NULL Message-ID: References: <20261023133316.64204-1-roger@xenproject.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20261023133316.64204-1-roger@xenproject.org> X-Spam-Status: No, score=-6.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=no 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 On Fri, Oct 23, 2026 at 03:33:16PM +0200, Roger Pau Monne wrote: > Both the normal and the compat versions of > VCPUOP_register_runstate_memory_area allow registering a NULL handler as a > way to signal deregistration of the previous area, and > update_runstate_area() will skip the update when the handler is NULL. > > However when handling the VCPUOP_register_runstate_memory_area hypercall > itself there's an unconditional attempt to update the newly registered > runstate area, without taking into account whether it points to NULL. Skip > such update if the user-provided handle is NULL. I've added: Fixes: 705ea2b54c35 ("New VCPUOP_register_runstate_memory_area hypercall.") Roger.