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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED 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 59B5BC282C4 for ; Tue, 12 Feb 2019 19:58:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 13E29222C4 for ; Tue, 12 Feb 2019 19:58:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="KNHi+B+A" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729733AbfBLT6N (ORCPT ); Tue, 12 Feb 2019 14:58:13 -0500 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:35500 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726044AbfBLT6N (ORCPT ); Tue, 12 Feb 2019 14:58:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1550001519; x=1581537519; h=subject:to:cc:references:from:message-id:date: mime-version:in-reply-to:content-transfer-encoding; bh=hwqIbYi5G3kRqkmsvPNoG9+WwfcisAP7zx393j6fDlk=; b=KNHi+B+ATvUYOXh/loAWWYHBV4KXUtLb2twxbX9YrQjcHd/LZJFgwvV0 sXSodRcY/lv3AmxPZYFOpFzl/HGkIa1hdhkmkJOCgLwM9lYfNfSrxsQC5 mqzdEBqgbsO+nVVvZ2khJl3l7Nbef1tzpo7zJwbyq/qzaeYmZJgIvRtPC Jii2IrnDylUTdA2QlCVWLOEJj+vmEf6gpK4KExJ+GrqzvwoonD8clQqdm 54Vckomiquxk6oxLRb/yajoAGkJMkF5WgMmGW9bP/hbiaVeQBgf130XDB JNP6ROiHe6+xHcEZsJI5Vc4xPOo5eLqUByUwtx9Of23OZJhPqfyneDiyF A==; X-IronPort-AV: E=Sophos;i="5.58,362,1544457600"; d="scan'208";a="199247381" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 13 Feb 2019 03:58:38 +0800 Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP; 12 Feb 2019 11:36:47 -0800 Received: from c02v91rdhtd5.sdcorp.global.sandisk.com (HELO [10.111.69.190]) ([10.111.69.190]) by uls-op-cesaip01.wdc.com with ESMTP; 12 Feb 2019 11:58:13 -0800 Subject: Re: [v4 PATCH 8/8] RISC-V: Assign hwcap as per comman capabilities. To: Johan Hovold Cc: "linux-riscv@lists.infradead.org" , Alan Kao , Albert Ou , Andreas Schwab , Anup Patel , Daniel Lezcano , Dmitriy Cherkasov , Jason Cooper , "linux-kernel@vger.kernel.org" , Marc Zyngier , Palmer Dabbelt , Paul Walmsley , Rob Herring , Thomas Gleixner References: <1549969812-22502-1-git-send-email-atish.patra@wdc.com> <1549969812-22502-9-git-send-email-atish.patra@wdc.com> <20190212112534.GB28278@localhost> From: Atish Patra Message-ID: <61766631-42f4-ec25-3b5c-ae892da44ccb@wdc.com> Date: Tue, 12 Feb 2019 11:58:10 -0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:60.0) Gecko/20100101 Thunderbird/60.5.0 MIME-Version: 1.0 In-Reply-To: <20190212112534.GB28278@localhost> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/12/19 3:25 AM, Johan Hovold wrote: > On Tue, Feb 12, 2019 at 03:10:12AM -0800, Atish Patra wrote: >> Currently, we set hwcap based on first valid hart from DT. This may not >> be correct always as that hart might not be current booting cpu or may >> have a different capability. >> >> Set hwcap as the capabilities supported by all possible harts with "okay" >> status. >> >> Signed-off-by: Atish Patra >> --- >> arch/riscv/kernel/cpufeature.c | 41 ++++++++++++++++++++++------------------- >> 1 file changed, 22 insertions(+), 19 deletions(-) >> >> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c >> index e7a4701f..a1e4fb34 100644 >> --- a/arch/riscv/kernel/cpufeature.c >> +++ b/arch/riscv/kernel/cpufeature.c >> @@ -20,6 +20,7 @@ >> #include >> #include >> #include >> +#include >> >> unsigned long elf_hwcap __read_mostly; >> #ifdef CONFIG_FPU >> @@ -42,28 +43,30 @@ void riscv_fill_hwcap(void) >> >> elf_hwcap = 0; >> >> - /* >> - * We don't support running Linux on hertergenous ISA systems. For >> - * now, we just check the ISA of the first "okay" processor. >> - */ >> for_each_of_cpu_node(node) { >> - if (riscv_of_processor_hartid(node) >= 0) >> - break; >> - } >> - if (!node) { >> - pr_warn("Unable to find \"cpu\" devicetree entry\n"); >> - return; >> - } >> + unsigned long this_hwcap = 0; >> >> - if (of_property_read_string(node, "riscv,isa", &isa)) { >> - pr_warn("Unable to find \"riscv,isa\" devicetree entry\n"); >> - of_node_put(node); >> - return; >> - } >> - of_node_put(node); >> + if (riscv_of_processor_hartid(node) < 0) >> + continue; >> >> - for (i = 0; i < strlen(isa); ++i) >> - elf_hwcap |= isa2hwcap[(unsigned char)(isa[i])]; >> + if (of_property_read_string(node, "riscv,isa", &isa)) { >> + pr_warn("Unable to find \"riscv,isa\" devicetree entry\n"); >> + return; > > Did you want "continue" here to continue processing the other harts? > Hmm. If a cpu node doesn't have isa in DT, that means DT is wrong. A "continue" here will let user space use other harts just with a warning message? Returning here will not set elf_hwcap which forces the user to fix the DT. I am not sure what should be the defined behavior in this case. Any thoughts ? > Note that you currently leak the device node when returning. > Ahh yes. I will fix it if we continue to return in the error case. Regards, Atish > Johan >