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dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.116172.221787 (Exim 4.92) (envelope-from ) id 1lZtVs-0004bo-3R; Fri, 23 Apr 2021 10:58:20 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 116172.221787; Fri, 23 Apr 2021 10:58:20 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lZtVr-0004bh-Vq; Fri, 23 Apr 2021 10:58:19 +0000 Received: by outflank-mailman (input) for mailman id 116172; Fri, 23 Apr 2021 10:58:19 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lZtVq-0004as-Tn for xen-devel@lists.xenproject.org; Fri, 23 Apr 2021 10:58:18 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 7252a128-bb93-432c-be5d-c7c5f4ae0642; Fri, 23 Apr 2021 10:58:17 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 94519B05E; Fri, 23 Apr 2021 10:58:16 +0000 (UTC) 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: 7252a128-bb93-432c-be5d-c7c5f4ae0642 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1619175496; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O1h7dIq+ewiuqz8410ZJWfplP+tNdNhZw1IeOdaurVQ=; b=sVvMyFmiUVUNqmwQkzvW57olf73ljfaCf6dAb6Xv3UVxtU1BBZ2GSg2rwLX13ew2i23kmQ H7aC5clPhKI6JKx/UYpmdmbWt7QR87/VJJhAgUABWiBSudTZUOVaMtuWw5wGa+fq17nyOS EPBfm+FPZMht/epJ8FHse7lzjaxz/90= Subject: Re: [PATCH] x86/oprof: fix !HVM && !PV32 build To: Andrew Cooper Cc: Wei Liu , "xen-devel@lists.xenproject.org" , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= References: <694c9c98-1197-3378-cc43-235e2609c1dd@suse.com> <98d0b627-de38-f7a0-7487-cbf83864c82f@citrix.com> From: Jan Beulich Message-ID: <135f8bc2-d07c-c531-e498-9f0e15207cca@suse.com> Date: Fri, 23 Apr 2021 12:58:16 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: <98d0b627-de38-f7a0-7487-cbf83864c82f@citrix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit On 23.04.2021 12:51, Andrew Cooper wrote: > On 23/04/2021 10:50, Roger Pau Monné wrote: >> On Fri, Apr 16, 2021 at 04:20:59PM +0200, Jan Beulich wrote: >>> On 16.04.2021 15:41, Andrew Cooper wrote: >>>> On 16/04/2021 09:16, Jan Beulich wrote: >>>>> clang, at the very least, doesn't like unused inline functions, unless >>>>> their definitions live in a header. >>>>> >>>>> Fixes: d23d792478 ("x86: avoid building COMPAT code when !HVM && !PV32") >>>>> Reported-by: Andrew Cooper >>>>> Signed-off-by: Jan Beulich >>>> I agree this will fix the build.  However, looking at the code, I'm not >>>> sure the original CONFIG_COMPAT was correct.  In particular, ... >>>> >>>>> --- a/xen/arch/x86/oprofile/backtrace.c >>>>> +++ b/xen/arch/x86/oprofile/backtrace.c >>>>> @@ -43,6 +43,7 @@ dump_hypervisor_backtrace(struct vcpu *v >>>>> return head->ebp; >>>>> } >>>>> >>>>> +#ifdef CONFIG_COMPAT >>>>> static inline int is_32bit_vcpu(struct vcpu *vcpu) >>>>> { >>>>> if (is_hvm_vcpu(vcpu)) >>>> ... this chunk of logic demonstrates that what oprofile is doing isn't >>>> related to the Xen ABI in the slightest. >>>> >>>> I think OProfile is misusing the guest handle infrastructure, and >>>> shouldn't be using it for this task. >>> I'm afraid I consider this something for another day. Both the >>> original #ifdef and the one getting added here are merely >>> measures to get things to build. >> Acked-by: Roger Pau Monné >> >> Without entering on the debate whether CONFIG_COMPAT is the correct >> conditional to use it's not making the issue any worse, and it will >> allow to unblock the build. We can discuss about the CONFIG_COMPAT >> stuff later. > > I disagree.  Fixing this less effort than the time wasted arguing about > fixing it. > > But if you are going to insist on not fixing it, and putting in a patch > like this, then at a minimum, it needs to include a TODO comment stating > that the use of CONFIG_COMPAT is bogus and needs fixing. I disagree: It is (for now) just you saying this is bogus. The (ab)use of the handle infrastructure was there before. You could have sent a fix long ago, therefore, if you were thinking this needs fixing. I can see that you have good intentions, but orthogonal issues shouldn't be used to block necessary adjustments (and this applies to other pending build fixes as well). Jan