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.gnu.org (lists.gnu.org [209.51.188.17]) (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 6B7C5C43334 for ; Tue, 5 Jul 2022 09:41:04 +0000 (UTC) Received: from localhost ([::1]:59658 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1o8f3H-0000dW-Ai for qemu-devel@archiver.kernel.org; Tue, 05 Jul 2022 05:41:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53404) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o8f23-00080h-Tn; Tue, 05 Jul 2022 05:39:47 -0400 Received: from mail-vk1-xa33.google.com ([2607:f8b0:4864:20::a33]:35750) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1o8f22-0005fL-8k; Tue, 05 Jul 2022 05:39:47 -0400 Received: by mail-vk1-xa33.google.com with SMTP id 18so69316vkz.2; Tue, 05 Jul 2022 02:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=f55/Q0yxAXTwoeHquimUiBIYY1pNggOvt1cs/q+ug6k=; b=pkY5cvisztOQyixu/khV3KMsS+cwQNRbO5dRJB767CSLUmbnqjYDIWxLFfGmnUFblM EtjIM5h9e1baTTrl8milk8inOCDX+CHgFIEIjhnRK7KmfUyu30J9sDXKVIUB4A2gOv/x IbYDNCOtVhyDhTjRj+p1MvuyCwfB3qzGvolTkCCrHdvMRTrls3yDZ3J2R6mzExUL17GH eRPKdhCuBCOFJ0qwHOqMcqRrOsTp6LCoV8gLWKfL0KC+LezuRODUSP8jGJ6KlgfKpQ5m 8Bw4pAHCKAkx6wAWwYXvEsbDr0AbREEUwiMgGx+TAgVqhIuL0GCr6aBvfRAar09OsCBM Ta1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=f55/Q0yxAXTwoeHquimUiBIYY1pNggOvt1cs/q+ug6k=; b=3Vgqu4vRu8XHu9vaiItrLovCMnbE3GyKr+t2cO3iUIUrMfVRcEakqoQvBf+kZfmsgc LkTAFRvJAY5kgjISiPPTQuvoEE1KNJ+GoESzaB0iUeHCJ7w+ACCM/G9MIeZUuJVSdu13 dI7HpquUBfhhTKLo2xCJvtLsRtpwxlMUhsqVYNYtlxtN1NceO5k2YRioYZA3RXD31y1N DyWjoos4O+SsdZrGN6ezT/WDNXpP9ekF//as+juzJTxJNcmM/8MpLuTmfCeFhWi5FNEl I3z3OUhsjBMw4YT8MkwiGE19lBebsJ/RgC4JSsMONjr+zdBivWQcr7eWwqB8kJBkM0xs HHGA== X-Gm-Message-State: AJIora+3IH3heq2elNifqUXj7lefA3sR5Wm/jkm1OQY5griicHEhcxaD Jyf0UZSeRTbGIqSUX421ugM= X-Google-Smtp-Source: AGRyM1uhFRG5pM1PcGurmPHReiLFnGhcXI8MvhClc2LKBACqAIqMfcB9rJTxqSwY4dMVLzMiWi5dAw== X-Received: by 2002:a1f:6d04:0:b0:36c:125:2edf with SMTP id i4-20020a1f6d04000000b0036c01252edfmr18989781vkc.38.1657013984647; Tue, 05 Jul 2022 02:39:44 -0700 (PDT) Received: from [192.168.10.102] ([191.193.1.105]) by smtp.gmail.com with ESMTPSA id k23-20020a1fa117000000b0035d04bf0a8csm6286977vke.1.2022.07.05.02.39.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 05 Jul 2022 02:39:44 -0700 (PDT) Message-ID: <38468531-5eb0-a421-f90f-2a3c67222d40@gmail.com> Date: Tue, 5 Jul 2022 06:39:39 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [PATCH 2/9] target/ppc: add errp to kvmppc_read_int_cpu_dt() Content-Language: en-US To: Mark Cave-Ayland , =?UTF-8?Q?C=c3=a9dric_Le_Goater?= , qemu-devel@nongnu.org Cc: qemu-ppc@nongnu.org References: <20220630194249.886747-1-danielhb413@gmail.com> <20220630194249.886747-3-danielhb413@gmail.com> <55014e2a-a668-4843-8338-850abeb5ff04@kaod.org> <47277f4f-a6a5-85dc-4806-67df8e2fc153@gmail.com> <6d37b1dc-5dfb-2513-f74e-3f58e84e8117@kaod.org> <1d2cd44f-fd61-4693-ecc0-f71c80131005@ilande.co.uk> From: Daniel Henrique Barboza In-Reply-To: <1d2cd44f-fd61-4693-ecc0-f71c80131005@ilande.co.uk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::a33; envelope-from=danielhb413@gmail.com; helo=mail-vk1-xa33.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 7/5/22 03:51, Mark Cave-Ayland wrote: > On 04/07/2022 18:34, Cédric Le Goater wrote: > >> On 7/2/22 15:34, Daniel Henrique Barboza wrote: >>> >>> >>> On 7/2/22 03:24, Cédric Le Goater wrote: >>>> On 6/30/22 21:42, Daniel Henrique Barboza wrote: >>>>> The function can't just return 0 whether an error happened and call it a >>>>> day. We must provide a way of letting callers know if the zero return is >>>>> legitimate or due to an error. >>>>> >>>>> Add an Error pointer to kvmppc_read_int_cpu_dt() that will be filled >>>>> with an appropriate error, if one occurs. Callers are then free to pass >>>>> an Error pointer and handle it. >>>>> >>>>> Signed-off-by: Daniel Henrique Barboza >>>>> --- >>>>>   target/ppc/kvm.c | 16 +++++++++------- >>>>>   1 file changed, 9 insertions(+), 7 deletions(-) >>>>> >>>>> diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c >>>>> index 109823136d..bc17437097 100644 >>>>> --- a/target/ppc/kvm.c >>>>> +++ b/target/ppc/kvm.c >>>>> @@ -1925,15 +1925,17 @@ static uint64_t kvmppc_read_int_dt(const char *filename) >>>>>   /* >>>>>    * Read a CPU node property from the host device tree that's a single >>>>> - * integer (32-bit or 64-bit).  Returns 0 if anything goes wrong >>>>> - * (can't find or open the property, or doesn't understand the format) >>>>> + * integer (32-bit or 64-bit).  Returns 0 and set errp if anything goes >>>>> + * wrong (can't find or open the property, or doesn't understand the >>>>> + * format) >>>>>    */ >>>>> -static uint64_t kvmppc_read_int_cpu_dt(const char *propname) >>>>> +static uint64_t kvmppc_read_int_cpu_dt(const char *propname, Error **errp) >>>>>   { >>>>>       char buf[PATH_MAX], *tmp; >>>>>       uint64_t val; >>>>>       if (kvmppc_find_cpu_dt(buf, sizeof(buf))) { >>>>> +        error_setg(errp, "Failed to read CPU property %s", propname); >>>>>           return 0; >>>>>       } >>>>> @@ -1946,12 +1948,12 @@ static uint64_t kvmppc_read_int_cpu_dt(const char *propname) >>>>>   uint64_t kvmppc_get_clockfreq(void) >>>>>   { >>>>> -    return kvmppc_read_int_cpu_dt("clock-frequency"); >>>>> +    return kvmppc_read_int_cpu_dt("clock-frequency", NULL); >>>> >>>> >>>> This should be fatal. no ? >>> >>> >>> I'm not sure. I went under the assumption that there might be some weird >>> condition where 'clock-frequency' might be missing from the DT, and this >>> is why we're not exiting out immediately. >>> >>> That said, the advantage of turning this into fatal is that we won't need >>> all the other patches that handles error on this function. We're going to >>> assume that if 'clock-frequency' is missing then we can't boot. I'm okay >>> with that. >> >> I think so. Some machines behave badly when 'clock-frequency' is bogus, >> division by zero, no console, etc. We could check easily with pseries >> which is the only KVM PPC platform. > > Well not quite true ;)  I haven't tested it during the last release cycle, but the Mac machines were still working fine to boot OS X with KVM-PR on my G4 Mac Mini last time I checked. We can't just error_fatal by default then. Each machine should be able to determine how to handle this missing DT element. If I want to error_fatal for pseries then I can do so in patch 9/9, but other than that I'll keep the existing behavior. Thanks, Daniel > > > ATB, > > Mark.