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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7EB6FC433EF for ; Fri, 27 May 2022 10:57:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350981AbiE0K5m (ORCPT ); Fri, 27 May 2022 06:57:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242359AbiE0K5k (ORCPT ); Fri, 27 May 2022 06:57:40 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4A8441059E4 for ; Fri, 27 May 2022 03:57:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653649058; h=from:from:reply-to:subject:subject: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=w/W1rjmpFLa1v2RHMPVw1HSemGhVAnYnW7IDz+nVRvU=; b=dOqQytcRWagiQX7alGKqfLg9DGB335er+jyv2wAQTzao8LNvh1VGFrzeLUexm3u5PYZ6H+ p6TjRMZ4Tip3zkpD0zvoLOhYgv1dYz5hYOdkoqAnEbcGN3lUqt6vRlNaxxzI09xupp4py+ GrfSeOiS22lGa0YPEnLwySib35s1qE4= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-477-jSclqcxJNDW64hEep1fi1Q-1; Fri, 27 May 2022 06:57:37 -0400 X-MC-Unique: jSclqcxJNDW64hEep1fi1Q-1 Received: by mail-ed1-f69.google.com with SMTP id e3-20020a056402330300b0042b903637bbso2822999eda.3 for ; Fri, 27 May 2022 03:57:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=w/W1rjmpFLa1v2RHMPVw1HSemGhVAnYnW7IDz+nVRvU=; b=zrx4zUg2v0uMAahcrihVJAU5FFfgF/gKulxzExW+vG5SZB9nv4nryRm1Oxo8K8huIJ yjYW4BMUhAbzFyUTudmw2AJt9jJFgDlkmKBw0AITVzpYu7dm2WdOuLHWzfPS13sidqpW aBooVwX6wIA31/qxy66ME5CoyT41lu1v+ocDpcfNyzMCDZv4cDq7/q3nbP5Yo4RdTtXK 5sIPZliL8C4bOaFDIhwxh7/6tdNzsCKNIqTPgtUCOtYVFNp37llEFRPgBqaiOH0Mlya0 MNrYgyRFmIphO8+stnBMiDmBLntvrCl2BM4RrSdct7j4dQJd77ObfeUCDPXU4p8i9pqK fHxg== X-Gm-Message-State: AOAM532AhKe0O3VSpD6khkfwX4AaX0xsukgKHNi8JPZ5zpIhDvqR3mTv fCMea3gWj1LjFeqvFZLyVJdIaBP5LdR0udawMUTs3oOnlqA3aTNtmQJ88Vzj03cg5PoMznWYsQe GLWz6fd1XW7jAHYcmbZkcSvxQ X-Received: by 2002:a17:907:6d85:b0:6fa:80ea:7565 with SMTP id sb5-20020a1709076d8500b006fa80ea7565mr38630247ejc.395.1653649055993; Fri, 27 May 2022 03:57:35 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwk6Jj1t6DUqc/RXpwAHg1SYPdtQFfHok9zAcciQ3wqDOE6E1PqZgNrOq+IAz4pxLa39lLnbQ== X-Received: by 2002:a17:907:6d85:b0:6fa:80ea:7565 with SMTP id sb5-20020a1709076d8500b006fa80ea7565mr38630235ejc.395.1653649055743; Fri, 27 May 2022 03:57:35 -0700 (PDT) Received: from redhat.com ([2.55.130.213]) by smtp.gmail.com with ESMTPSA id kx17-20020a170907775100b006feded0fa87sm1330944ejc.218.2022.05.27.03.57.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 May 2022 03:57:35 -0700 (PDT) Date: Fri, 27 May 2022 06:57:32 -0400 From: "Michael S. Tsirkin" To: Bo Liu =?utf-8?B?KOWImOazoikt5rWq5r2u5L+h5oGv?= Cc: "david@redhat.com" , "jasowang@redhat.com" , "virtualization@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] virtio_balloon: check virtqueue_add_outbuf() return value Message-ID: <20220527065611-mutt-send-email-mst@kernel.org> References: <4789cbbb9d59420abc86a9e225ef0bfd@inspur.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4789cbbb9d59420abc86a9e225ef0bfd@inspur.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 27, 2022 at 10:43:30AM +0000, Bo Liu (刘波)-浪潮信息 wrote: > The purpose of this patch is, virtqueue_add_outbuf() adding data to > virtqueue may succeed or fail. If successful, it will call virtqueue_kick() > to notifie the host backend driver, but if the virtqueue_add_outbuf() fails, > the data is not successfully added to the virtqueue, and the host back-end > driver does not need to be notified for processing. > > Thanks. Why is it a problem if we do? -- MST 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 smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 49FA5C433F5 for ; Fri, 27 May 2022 10:57:44 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id C9702428A4; Fri, 27 May 2022 10:57:43 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1z7jbfl0vpzF; Fri, 27 May 2022 10:57:42 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTPS id 4900042853; Fri, 27 May 2022 10:57:42 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 11523C0032; Fri, 27 May 2022 10:57:42 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 3F47FC002D for ; Fri, 27 May 2022 10:57:40 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 1CC91615F8 for ; Fri, 27 May 2022 10:57:40 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp3.osuosl.org (amavisd-new); dkim=pass (1024-bit key) header.d=redhat.com Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QN5j36p9axxh for ; Fri, 27 May 2022 10:57:39 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by smtp3.osuosl.org (Postfix) with ESMTPS id 72B0A6106F for ; Fri, 27 May 2022 10:57:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653649058; h=from:from:reply-to:subject:subject: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=w/W1rjmpFLa1v2RHMPVw1HSemGhVAnYnW7IDz+nVRvU=; b=dOqQytcRWagiQX7alGKqfLg9DGB335er+jyv2wAQTzao8LNvh1VGFrzeLUexm3u5PYZ6H+ p6TjRMZ4Tip3zkpD0zvoLOhYgv1dYz5hYOdkoqAnEbcGN3lUqt6vRlNaxxzI09xupp4py+ GrfSeOiS22lGa0YPEnLwySib35s1qE4= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-502-LF0Mc8IYOCiMpjoN6zmWqA-1; Fri, 27 May 2022 06:57:37 -0400 X-MC-Unique: LF0Mc8IYOCiMpjoN6zmWqA-1 Received: by mail-ed1-f69.google.com with SMTP id s3-20020aa7d783000000b0042d660a4efeso230454edq.20 for ; Fri, 27 May 2022 03:57:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=w/W1rjmpFLa1v2RHMPVw1HSemGhVAnYnW7IDz+nVRvU=; b=xrc8Vu5oAJF7WAYmbH2TNMGI1/pNj8Y1bgZPJQ/bQLOZJ2F9VKI0zpIj6gRi2saB7m WuzvnnfS6xaBpR5m0nreIh/MSFhdk3UYD/UuN3+Wf8WcQ1U04lLycYondxH8DxTRmbph Y7koW//BY+3FhQJV2xb+LcVyB0We5qVwCaAN/ee2yFIpE7IgZUYk69M43mmtk7Cp6Iyc 2pJuIsqEm2rrfPUXeZtyvLjk3EO5Vdn6q4Fr51IouulinC0Dh/sDQmjfgMgziHlE6AtR IX/6Ix9Vmt8arfWqFy+quJYNuqCe6dR+sHCaxr8HaSW4t+sBC01h37ycvRHT2Bg0ynO6 9Q7w== X-Gm-Message-State: AOAM532QbuAGDIOlHtwiA4oTLyRSN5NsA138zzD+HoOKq4pd9CfMt7jb 5rzWWvgI6KrhtFD2AwIT0dsHSl2mQu+f8Bp1dG1QdwoIUK/7r4OMKhGmVRbQSrCnCxaniruvswx Yg2gwRdFJjzjvuMW9cVwmBbEQCfokwMF7G204OmalxA== X-Received: by 2002:a17:907:6d85:b0:6fa:80ea:7565 with SMTP id sb5-20020a1709076d8500b006fa80ea7565mr38630249ejc.395.1653649055993; Fri, 27 May 2022 03:57:35 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwk6Jj1t6DUqc/RXpwAHg1SYPdtQFfHok9zAcciQ3wqDOE6E1PqZgNrOq+IAz4pxLa39lLnbQ== X-Received: by 2002:a17:907:6d85:b0:6fa:80ea:7565 with SMTP id sb5-20020a1709076d8500b006fa80ea7565mr38630235ejc.395.1653649055743; Fri, 27 May 2022 03:57:35 -0700 (PDT) Received: from redhat.com ([2.55.130.213]) by smtp.gmail.com with ESMTPSA id kx17-20020a170907775100b006feded0fa87sm1330944ejc.218.2022.05.27.03.57.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 May 2022 03:57:35 -0700 (PDT) Date: Fri, 27 May 2022 06:57:32 -0400 From: "Michael S. Tsirkin" To: Bo Liu =?utf-8?B?KOWImOazoikt5rWq5r2u5L+h5oGv?= Subject: Re: [PATCH] virtio_balloon: check virtqueue_add_outbuf() return value Message-ID: <20220527065611-mutt-send-email-mst@kernel.org> References: <4789cbbb9d59420abc86a9e225ef0bfd@inspur.com> MIME-Version: 1.0 In-Reply-To: <4789cbbb9d59420abc86a9e225ef0bfd@inspur.com> Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Cc: "virtualization@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" T24gRnJpLCBNYXkgMjcsIDIwMjIgYXQgMTA6NDM6MzBBTSArMDAwMCwgQm8gTGl1ICjliJjms6Ip Lea1qua9ruS/oeaBryB3cm90ZToKPiBUaGUgcHVycG9zZSBvZiB0aGlzIHBhdGNoIGlzLCB2aXJ0 cXVldWVfYWRkX291dGJ1ZigpIGFkZGluZyBkYXRhIHRvCj4gdmlydHF1ZXVlIG1heSBzdWNjZWVk IG9yIGZhaWwuIElmIHN1Y2Nlc3NmdWwsIGl0IHdpbGwgY2FsbCB2aXJ0cXVldWVfa2ljaygpCj4g dG8gbm90aWZpZSB0aGUgaG9zdCBiYWNrZW5kIGRyaXZlciwgYnV0IGlmIHRoZSB2aXJ0cXVldWVf YWRkX291dGJ1ZigpIGZhaWxzLAo+IHRoZSBkYXRhIGlzIG5vdCBzdWNjZXNzZnVsbHkgYWRkZWQg dG8gdGhlIHZpcnRxdWV1ZSwgYW5kIHRoZSBob3N0IGJhY2stZW5kCj4gZHJpdmVyIGRvZXMgbm90 IG5lZWQgdG8gYmUgbm90aWZpZWQgZm9yIHByb2Nlc3NpbmcuCj4gCj4gVGhhbmtzLgoKV2h5IGlz IGl0IGEgcHJvYmxlbSBpZiB3ZSBkbz8KCi0tIApNU1QKCl9fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fClZpcnR1YWxpemF0aW9uIG1haWxpbmcgbGlzdApWaXJ0 dWFsaXphdGlvbkBsaXN0cy5saW51eC1mb3VuZGF0aW9uLm9yZwpodHRwczovL2xpc3RzLmxpbnV4 Zm91bmRhdGlvbi5vcmcvbWFpbG1hbi9saXN0aW5mby92aXJ0dWFsaXphdGlvbg==