From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3CBDA69D2B; Sat, 28 Dec 2024 10:24:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735381450; cv=none; b=p9qJUkUrAHhzDbjZgp8MtGrzuSVlT07YmmaBVfPEAL/RGHhkPs383OlK5ad+vYXV+gVAmLhxdpLXP8p+sbjQx3hFU//tFLmNLKUCFBv/QR+nEGmMG5WKdMRwCaC27dOiubnphv8qwhHa0DXAIUtkbCiwCpIkrEYvDsX8hgzcX70= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1735381450; c=relaxed/simple; bh=YngjxGWq1Tv+ALdG1TKrseFe9btby2iXeFwHDXig0dk=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=V1GXhtyHVKkXTww2U5GixG/UGmVxOIE5Jc6pIubEyYEscGrcRlCW2y8QoV5wgAuHAxdmApcKNU9g+Kyt9XesWFVcDIHFwEqDJuU5wqka27pNjK8ccOZi4/nG9RoEig/tbFQTi4HNVD+2NWF1H3CRfAjBYDp9AfxN7yzSSl16Ml8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.252]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4YKz0S4JN2zgZVc; Sat, 28 Dec 2024 18:20:56 +0800 (CST) Received: from dggpemf200009.china.huawei.com (unknown [7.185.36.246]) by mail.maildlp.com (Postfix) with ESMTPS id 335EE180A9E; Sat, 28 Dec 2024 18:23:57 +0800 (CST) Received: from [10.67.121.188] (10.67.121.188) by dggpemf200009.china.huawei.com (7.185.36.246) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Sat, 28 Dec 2024 18:23:56 +0800 Message-ID: Date: Sat, 28 Dec 2024 18:23:56 +0800 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.3.2 Subject: Re: [PATCH] acpi: Fix hed module initialization order when it is built-in To: Jonathan Cameron CC: "Rafael J. Wysocki" , , , , , , , , , References: <20241115035014.1339256-1-tanxiaofei@huawei.com> <20241223193300.00000b32@huawei.com> From: Xiaofei Tan In-Reply-To: <20241223193300.00000b32@huawei.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemf200009.china.huawei.com (7.185.36.246) Hi Jonathan, 在 2024/12/24 3:33, Jonathan Cameron 写道: > On Mon, 23 Dec 2024 17:31:08 +0800 > Xiaofei Tan wrote: > >> Hi Rafael, >> >> 在 2024/12/11 1:59, Rafael J. Wysocki 写道: >>> On Fri, Nov 15, 2024 at 4:56 AM Xiaofei Tan wrote: >>>> When the module hed is built-in, the init order is determined by >>>> Makefile order. >>> Are you sure? >> yes > We had a similar fix in CXL recently (which is why I suggested this approach > internally when tanxiaofei mentioned the problem). > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/cxl?id=6575b268157f37929948a8d1f3bafb3d7c055bc1 > > The related discussion for the CXL patch was the first time I'd come across solution > to load order for built in cases. > Yes :) >>>> That order violates expectations. Because the module >>>> hed init is behind evged. RAS records can't be handled in the >>>> special time window that evged has initialized while hed not. >>>> If the number of such RAS records is more than the APEI HEST error >>>> source number, the HEST resources could be occupied all, and then >>>> could affect subsequent RAS error reporting. >>> Well, the problem is real, but does the change really prevent it from >>> happening or does it just increase the likelihood of success? >> It can be completely solved if the driver used as built-in way. If build HED as a >> module, it not solved. > Can we enforce that condition not happening with appropriate Kconfig? > It's annoying to restrict build options, but if needed to make it work > then better than not working! Agree,  i will change ACPI_HED from tristate to bool if there are no other comments, thanks. > > Jonathan > > >>> In the latter case, and generally speaking too, it would be better to >>> add explicit synchronization between evged and hed. >>> >>>> Reviewed-by: Jonathan Cameron >>>> Signed-off-by: Xiaofei Tan >>>> --- >>>> drivers/acpi/Makefile | 8 +++++++- >>>> 1 file changed, 7 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile >>>> index 61ca4afe83dc..54f60b7922ad 100644 >>>> --- a/drivers/acpi/Makefile >>>> +++ b/drivers/acpi/Makefile >>>> @@ -15,6 +15,13 @@ endif >>>> >>>> obj-$(CONFIG_ACPI) += tables.o >>>> >>>> +# >>>> +# The hed.o needs to be in front of evged.o to avoid the problem that >>>> +# RAS errors cannot be handled in the special time window of startup >>>> +# phase that evged has initialized while hed not. >>>> +# >>>> +obj-$(CONFIG_ACPI_HED) += hed.o >>>> + >>>> # >>>> # ACPI Core Subsystem (Interpreter) >>>> # >>>> @@ -95,7 +102,6 @@ obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o >>>> obj-$(CONFIG_ACPI_BATTERY) += battery.o >>>> obj-$(CONFIG_ACPI_SBS) += sbshc.o >>>> obj-$(CONFIG_ACPI_SBS) += sbs.o >>>> -obj-$(CONFIG_ACPI_HED) += hed.o >>>> obj-$(CONFIG_ACPI_EC_DEBUGFS) += ec_sys.o >>>> obj-$(CONFIG_ACPI_BGRT) += bgrt.o >>>> obj-$(CONFIG_ACPI_CPPC_LIB) += cppc_acpi.o >>>> -- >>>> 2.33.0 >>>> >>> . > .