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 2D37BC433EF for ; Wed, 11 May 2022 12:37:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242524AbiEKMhr (ORCPT ); Wed, 11 May 2022 08:37:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242526AbiEKMhj (ORCPT ); Wed, 11 May 2022 08:37:39 -0400 Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFF991FD878 for ; Wed, 11 May 2022 05:37:33 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=xianting.tian@linux.alibaba.com;NM=1;PH=DS;RN=18;SR=0;TI=SMTPD_---0VCwIZRf_1652272646; Received: from B-LB6YLVDL-0141.local(mailfrom:xianting.tian@linux.alibaba.com fp:SMTPD_---0VCwIZRf_1652272646) by smtp.aliyun-inc.com(127.0.0.1); Wed, 11 May 2022 20:37:28 +0800 Subject: Re: [PATCH] RISC-V: Remove IORESOURCE_BUSY flag for no-map reserved memory To: David Hildenbrand , paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, akpm@linux-foundation.org, anup@brainfault.org, wangkefeng.wang@huawei.com, rppt@kernel.org, alex@ghiti.fr, twd2.me@gmail.com, seanjc@google.com, petr.pavlu@suse.com, atishp@rivosinc.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, guoren@kernel.org, jianghuaming.jhm@alibaba-inc.com, Nick Kossifidis References: <20220511112413.559734-1-xianting.tian@linux.alibaba.com> <4407c84b-a64f-51b0-fa96-388aaf3b3e35@redhat.com> From: Xianting Tian Message-ID: Date: Wed, 11 May 2022 20:37:26 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <4407c84b-a64f-51b0-fa96-388aaf3b3e35@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2022/5/11 下午8:27, David Hildenbrand 写道: > On 11.05.22 13:24, Xianting Tian wrote: >> Commit 00ab027a3b82 ("RISC-V: Add kernel image sections to the resource tree") >> added IORESOURCE_BUSY flag for no-map reserved memory, this casued >> devm_ioremap_resource() failed for the no-map reserved memory in subsequent >> operations of related driver, so remove the IORESOURCE_BUSY flag. >> >> The code to reproduce the issue, >> dts: >> mem0: memory@a0000000 { >> reg = <0x0 0xa0000000 0 0x1000000>; >> no-map; >> }; >> >> &test { >> status = "okay"; >> memory-region = <&mem0>; >> }; >> >> code: >> np = of_parse_phandle(pdev->dev.of_node, "memory-region", 0); >> ret = of_address_to_resource(np, 0, &r); >> base = devm_ioremap_resource(&pdev->dev, &r); >> // base = -EBUSY >> >> Fixes: 00ab027a3b82 ("RISC-V: Add kernel image sections to the resource tree") >> Reported-by: Huaming Jiang >> Reviewed-by: Guo Ren >> CC: Nick Kossifidis >> Signed-off-by: Xianting Tian >> --- >> arch/riscv/kernel/setup.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c >> index 834eb652a7b9..71f2966b1474 100644 >> --- a/arch/riscv/kernel/setup.c >> +++ b/arch/riscv/kernel/setup.c >> @@ -214,7 +214,7 @@ static void __init init_resources(void) >> >> if (unlikely(memblock_is_nomap(region))) { >> res->name = "Reserved"; >> - res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; >> + res->flags = IORESOURCE_MEM; >> } else { >> res->name = "System RAM"; >> res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; > I assume the "Reserved" part is essentially unused by the kernel correct? I think we may use it, actually we found the issue in our product after merged kdump functionality. Actually, the code didn't add IORESOURCE_BUSY for no-map reserved memory before 00ab027a3b82 merged,  so it is a typo for commit 00ab027a3b82 to add IORESOURCE_BUSY? >