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=-7.1 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 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 C4583C1975A for ; Mon, 16 Mar 2020 08:47:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D86B206B1 for ; Mon, 16 Mar 2020 08:47:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584348438; bh=1tLbDYlqlB6pPxS950lezICdCwJX/DkBWBo6RPPowVs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=ArIxOBiVtmEhJ95Sm2tSvm2JY0xXKCYGDmZ0xR8k8D5OXcclhdielLo7JFFCOtP6V XzP4g7LBBRMt4zc8l4ecVloKH9uW8gcuSkWnsvrGecAEbFh98NZVGw/mtHfZnXPq/c qxc4mnuZCuYf8FmrP2C3/yDM4Gzw93i1MPgzcPxU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730226AbgCPIrR (ORCPT ); Mon, 16 Mar 2020 04:47:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:52546 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730118AbgCPIrR (ORCPT ); Mon, 16 Mar 2020 04:47:17 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6866D20663; Mon, 16 Mar 2020 08:47:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584348436; bh=1tLbDYlqlB6pPxS950lezICdCwJX/DkBWBo6RPPowVs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=MXkiHRnGStNQyTlodxWkuHXastLZkGJkb7OLk/FHj1hl/UCQ6j2bYI62EmkG4J7TR D2kJ/P+rnMxDsnFgzM4UIyrq9WVXg2lAglGP9ZG6LlyPOBneyi6atsl8TaUcrmmx5q l0XJq2Snnpt9K9hq67O0stHiozFAX6xosSezw0j0= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1jDlP0-00D1q7-Ow; Mon, 16 Mar 2020 08:47:14 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Mon, 16 Mar 2020 08:47:14 +0000 From: Marc Zyngier To: Shaokun Zhang Cc: linux-kernel@vger.kernel.org, Nianyao Tang , Thomas Gleixner Subject: Re: [PATCH] irqchip/gic-v4: Fix non-stick page size error for setup GITS_BASER In-Reply-To: References: <1584089195-63897-1-git-send-email-zhangshaokun@hisilicon.com> <9a00642020fe660e005045913b57fd20@kernel.org> Message-ID: X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/1.3.10 X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: zhangshaokun@hisilicon.com, linux-kernel@vger.kernel.org, tangnianyao@huawei.com, tglx@linutronix.de X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Shaokun, On 2020-03-16 05:48, Shaokun Zhang wrote: > Hi Marc， > > On 2020/3/13 20:00, Marc Zyngier wrote: >> Shaokun, Nianyao, >> >> On 2020-03-13 08:46, Shaokun Zhang wrote: >>> From: Nianyao Tang >>> >>> There is an error when ITS is probed if hw GITS_BASER<2> >>> only supports psz=SZ_16K while GITS_BASER<1> only supports psz=SZ_4K. >>> In its_alloc_tables, it has updated GITS_BASER<1>.psz and uses >>> psz=SZ_4K for setup GITS_BASER<2>, and would fail in writing >>> GITS_BASER<2>.psz=SZ_4K. 4K PAGE is the smallest and shall stop retry >>> for other page sizes. >>> >>> That latter GITS_BASER.psz is larger than former, will lead >>> to similar error. >>> >>> [ 0.000000] ITS@0x0000000660000000: Virtual CPUs doesn't stick: >>> ba1f0824404004ff ba1f0824404005ff >>> [ 0.000000] ITS@0x0000000660000000: failed probing (-6) >>> [ 0.000000] ITS: No ITS available, not enabling LPIs >>> >>> From GIC SPEC document, it's allowed for this implematation, the >>> latter >>> GITS_BASER.psz is larger than the former. >> >> I was really hoping nobody would build an ITS with disjoint sets of >> page sizes. Oh well... >> >>> Let's fix this error with following patch. >>> >>> Cc: Thomas Gleixner >>> Cc: Marc Zyngier >>> Signed-off-by: Nianyao Tang >>> Signed-off-by: Shaokun Zhang >>> --- >>> drivers/irqchip/irq-gic-v3-its.c | 1 - >>> 1 file changed, 1 deletion(-) >>> >>> diff --git a/drivers/irqchip/irq-gic-v3-its.c >>> b/drivers/irqchip/irq-gic-v3-its.c >>> index 83b1186..59bf8d6 100644 >>> --- a/drivers/irqchip/irq-gic-v3-its.c >>> +++ b/drivers/irqchip/irq-gic-v3-its.c >>> @@ -2341,7 +2341,6 @@ static int its_alloc_tables(struct its_node >>> *its) >>> } >>> >>> /* Update settings which will be used for next BASERn */ >>> - psz = baser->psz; >>> cache = baser->val & GITS_BASER_CACHEABILITY_MASK; >>> shr = baser->val & GITS_BASER_SHAREABILITY_MASK; >>> } >> >> I think this just papers over the problem, and I'd rather tackle it >> fully >> by forcing the probe of the supported page sizes for each GITS_BASERn >> register. See the patch below (which I've only boot-tested once on >> pretty >> standard HW as well as a guest). >> >> This, in turn, simplifies the way we perform the allocation (no nested >> retry loop). This is of course a much more patch invasive, but at >> least >> it doesn't leave too much cruft behind. >> >> Please let me know whether this solves your issue. >> > > Thanks your quick reply. > With your following fixed patch, it can work for Nianyao, So: > Tested-by: Nianyao Tang Thanks for the quick feedback. I've now added this patch to the 5.7 queue. M. -- Jazz is not dead. It just smells funny...