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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E67B6C5ACD6 for ; Tue, 17 Mar 2020 17:36:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE57920735 for ; Tue, 17 Mar 2020 17:36:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584466565; bh=vCkXg6ZKTmn/Kw2NcMY6GpGnLUbXdCNDQFCJeGQBEAE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=kQRJu3gSGha+mYbvHzxl55MmuR+3k+5r5Cy0O/XhTr1fK8pueucGi/acDV/sGflHp XH1P1MosNTQWqoxqpj94lIA8txGdz5FN3oo1IKiiDzfsorlTq0WO8UkAzCcNHknEB/ lFHFELxc9xfy56mdOsKTHdmxcnhPX7YhgJQdNRAQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726189AbgCQRgF (ORCPT ); Tue, 17 Mar 2020 13:36:05 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:37196 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726680AbgCQRgE (ORCPT ); Tue, 17 Mar 2020 13:36:04 -0400 Received: by mail-wr1-f68.google.com with SMTP id 6so26811177wre.4; Tue, 17 Mar 2020 10:36:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=HK4dtU6wlFNqeoi15VIX4txP4pHLLBJv5Yu+/ozsMlo=; b=mfTsH6hLkOkCjRj90Xkh5eCAR1D8QvYRXBBDfM8ysrjex48uAq8j5cAOBXgu3aTKkZ tn+83Bf+sSBGoRNjUBMS+E6fEqlG93CuiPBKbsz/G2FhW0ydRoBvR6DE8NG09NiOkr1a iOg3HgM1xrqUfFyy1zcz5eSFR7wANA3lZEOTpAPnMaIbRghlgBKFTS6nsDVX9kKPegpt ztlv4gm7AYqyvjw/6IlaGr+GNwhTvEyrVlum9UT6tWTOU3spONGeE0EGTGKvFKsS2oG7 aA+ZcfIbLfQr4YeZRWcPWSf1K/0FzLE5sn3RmtXWIdzaYOFEPzt6pyBijk6pNJYX2O7x c3gQ== X-Gm-Message-State: ANhLgQ2S7iOPCkwz0mak60Xlg8n4kBvv60XQfjg9DIMWn0XLXizdUmIN gEcCmHQDH202hK2JWUwlo58= X-Google-Smtp-Source: ADFU+vu9SYdwcgSZ2H4PuIVI9Wp9pPurJ3waoqVZWzO5zEOoKjPO/99OtjvJeY7eWQrGvPrFKK8lGg== X-Received: by 2002:a5d:4ac2:: with SMTP id y2mr69149wrs.263.1584466563140; Tue, 17 Mar 2020 10:36:03 -0700 (PDT) Received: from debian (41.142.6.51.dyn.plus.net. [51.6.142.41]) by smtp.gmail.com with ESMTPSA id k126sm202548wme.4.2020.03.17.10.36.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Mar 2020 10:36:02 -0700 (PDT) Date: Tue, 17 Mar 2020 17:36:00 +0000 From: Wei Liu To: ltykernel@gmail.com Cc: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, liuwe@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, x86@kernel.org, michael.h.kelley@microsoft.com, Tianyu Lan , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, vkuznets@redhat.com, Wei Liu Subject: Re: [PATCH 2/4] x86/Hyper-V: Free hv_panic_page when fail to register kmsg dump Message-ID: <20200317173600.2hqznyabyj4nckjo@debian> References: <20200317132523.1508-1-Tianyu.Lan@microsoft.com> <20200317132523.1508-3-Tianyu.Lan@microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200317132523.1508-3-Tianyu.Lan@microsoft.com> User-Agent: NeoMutt/20180716 Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On Tue, Mar 17, 2020 at 06:25:21AM -0700, ltykernel@gmail.com wrote: > From: Tianyu Lan > > If fail to register kmsg dump on Hyper-V platform, hv_panic_page > will not be used anywhere. So free and reset it. > > Signed-off-by: Tianyu Lan > --- > drivers/hv/vmbus_drv.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c > index b56b9fb9bd90..b043efea092a 100644 > --- a/drivers/hv/vmbus_drv.c > +++ b/drivers/hv/vmbus_drv.c > @@ -1385,9 +1385,13 @@ static int vmbus_bus_init(void) > hv_panic_page = (void *)hv_alloc_hyperv_zeroed_page(); > if (hv_panic_page) { > ret = kmsg_dump_register(&hv_kmsg_dumper); > - if (ret) > + if (ret) { > pr_err("Hyper-V: kmsg dump register " > "error 0x%x\n", ret); > + hv_free_hyperv_page( > + (unsigned long)hv_panic_page); > + hv_panic_page = NULL; > + } While this modification looks correct to me, there is a call to free hv_panic_page in the err_alloc path. That makes the error handling a bit confusing here. I think you can just remove that function call in err_alloc path. Wei. > } else > pr_err("Hyper-V: panic message page memory " > "allocation failed"); > -- > 2.14.5 >