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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 55547C2BD09 for ; Wed, 3 Jul 2024 08:19:04 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.752786.1161011 (Exim 4.92) (envelope-from ) id 1sOvCL-00026x-91; Wed, 03 Jul 2024 08:18:41 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 752786.1161011; Wed, 03 Jul 2024 08:18:41 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sOvCL-00026q-6R; Wed, 03 Jul 2024 08:18:41 +0000 Received: by outflank-mailman (input) for mailman id 752786; Wed, 03 Jul 2024 08:18:40 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sOvCK-00026k-Fe for xen-devel@lists.xenproject.org; Wed, 03 Jul 2024 08:18:40 +0000 Received: from mail-lf1-x129.google.com (mail-lf1-x129.google.com [2a00:1450:4864:20::129]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id d8f9ae42-3914-11ef-8776-851b0ebba9a2; Wed, 03 Jul 2024 10:18:37 +0200 (CEST) Received: by mail-lf1-x129.google.com with SMTP id 2adb3069b0e04-52e764bb3fbso6838493e87.3 for ; Wed, 03 Jul 2024 01:18:37 -0700 (PDT) Received: from localhost ([213.195.124.163]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3678c379cc6sm2873123f8f.49.2024.07.03.01.18.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Jul 2024 01:18:36 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: d8f9ae42-3914-11ef-8776-851b0ebba9a2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=google; t=1719994717; x=1720599517; darn=lists.xenproject.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=TOZyxlS/Noxst2/gNExI/arop/PCwkaNAvZtpITBPRA=; b=Ss/QDBGIXj5HVqasjmyiMX98NvmtrnK5jH8ah3uYLUzgfrcasgwu1fPyBSuwA0RlHD BqjiKuUBpWgP0aEWcigbydWnZQ52xpjLzwDWqbiE5SwKmFQXClWZr6rsQ7pnDaKevGNb x4rsf281/QAMr6cdQD6ElVgL+Y40No5PfAHZ4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719994717; x=1720599517; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=TOZyxlS/Noxst2/gNExI/arop/PCwkaNAvZtpITBPRA=; b=UlpdR0sA/9OVcQ5wviqHWOx12AE34v5+RUpN2sYC/J5gGjd2k/uUJpr3wzRrSuRWW+ Yh+fv3yEB2RRM5oV84FWqQaxhpSEmOZ/qz0SIgVC6oLBsgf/cMlyJCJWnOjAkIE1N4si 6GzZgwOcMmS8+4B58NDJy2q2ECU6YITzwDE90XLUrdMvOr6auR7oLp78RKtUB9A+4kad rVG8OsZY/LgZoxeiat5QR/LOtgeOnnZpCzmng1KqecSipS44wgm0vricuBtzv5atEIu1 VlLpR/9WwmWo8KYm/zkSjnWj8uMMvUXruZoHfwSCJQB9TWN8QzxB1g9ixjtBLJVA0FWZ UQYQ== X-Gm-Message-State: AOJu0YzXdHpplW8itQ1o6r/cCKLGUkGWaNs4xZ7nSZNPFAHDiGdeowHx 5qxUyvTmbNzbejWPWvYqTlfKCh1dTjjzCwWB5cygP0TKOe7BIXCeJgsrJGwu6k8= X-Google-Smtp-Source: AGHT+IFslHO1Ik6gGQPwnDjGwuE+S/XsP1kdXU21bVE8suOp3XU1LWj29jX0pPQjv8Qo8AVcL2eTRw== X-Received: by 2002:a05:6512:ac4:b0:52e:7684:a385 with SMTP id 2adb3069b0e04-52e826fc38dmr6576067e87.52.1719994716580; Wed, 03 Jul 2024 01:18:36 -0700 (PDT) Date: Wed, 3 Jul 2024 10:18:35 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jan Beulich Cc: "xen-devel@lists.xenproject.org" , Andrew Cooper , Julien Grall , Stefano Stabellini , Wei Liu , Oleksii Kurochko Subject: Re: [PATCH v4 for-4.19? 2/2] cmdline: "extra_guest_irqs" is inapplicable to PVH Message-ID: References: <03f6674c-f2d1-4ec1-995e-a3e25278ceac@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Jul 03, 2024 at 10:00:51AM +0200, Jan Beulich wrote: > On 03.07.2024 09:51, Roger Pau Monné wrote: > > On Tue, Jul 02, 2024 at 11:52:38AM +0200, Jan Beulich wrote: > >> PVH in particular has no (externally visible) notion of pIRQ-s. Mention > >> that in the description of the respective command line option and have > >> arch_hwdom_irqs() also reflect this (thus suppressing the log message > >> there as well, as being pretty meaningless in this case anyway). > >> > >> Suggested-by: Roger Pau Monné > >> Signed-off-by: Jan Beulich > >> --- > >> Since the EOI map physdevop-s aren't available to HVM no matter whether > >> the PVH sub-flavor is meant, the condition could in principle be without > >> the has_pirq() part. Just that there really isn't any "pure HVM" Dom0. > >> --- > >> v4: New. > >> > >> --- a/docs/misc/xen-command-line.pandoc > >> +++ b/docs/misc/xen-command-line.pandoc > >> @@ -1178,7 +1178,8 @@ versa. For example to change dom0 witho > >> hardware domain is architecture dependent. The upper limit for both values on > >> x86 is such that the resulting total number of IRQs can't be higher than 32768. > >> Note that specifying zero as domU value means zero, while for dom0 it means > >> -to use the default. > >> +to use the default. Note further that the Dom0 setting has no useful meaning > >> +for the PVH case; use of the option may have an adverse effect there, though. > > > > I would maybe remove the has_pirq() check and just mention in the > > comment added ahead of the is_hvm_domain() check that PVH/HVM guests > > never have access to the PHYSDEVOP_pirq_eoi_gmfn_v{1,2} hypercall, > > regardless of whether XENFEAT_hvm_pirqs is exposed. > > > > Would that be OK with you? > > Okay-ish. That's why I had the post-commit-message remark on this very aspect. I think adding the has_pirq() check is confusing, as the option is not available to PVH. Even if it was available it won't change the fact that PHYSDEVOP_pirq_eoi_gmfn_v{1,2} hypercall is not reachable. Thanks, Roger.