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=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 896BFC2D0A3 for ; Tue, 3 Nov 2020 13:35:57 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D2F0D2224E for ; Tue, 3 Nov 2020 13:35:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D2F0D2224E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 4C73C20013; Tue, 3 Nov 2020 13:35:56 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Ca3XMJvuTrnp; Tue, 3 Nov 2020 13:35:55 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 3D2B520003; Tue, 3 Nov 2020 13:35:55 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 17915C088B; Tue, 3 Nov 2020 13:35:55 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id DBCF9C0051 for ; Tue, 3 Nov 2020 13:35:53 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id C222286C39 for ; Tue, 3 Nov 2020 13:35:53 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Fyhm2gY9J4+3 for ; Tue, 3 Nov 2020 13:35:53 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by whitealder.osuosl.org (Postfix) with ESMTPS id 13D8886C23 for ; Tue, 3 Nov 2020 13:35:53 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 7FD9A433; Tue, 3 Nov 2020 14:35:51 +0100 (CET) Date: Tue, 3 Nov 2020 14:35:50 +0100 From: Joerg Roedel To: Suravee Suthikulpanit Subject: Re: [PATCH] iommu/amd: Enforce 4k mapping for certain IOMMU data structures Message-ID: <20201103133549.GI22888@8bytes.org> References: <20201028231824.56504-1-suravee.suthikulpanit@amd.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201028231824.56504-1-suravee.suthikulpanit@amd.com> User-Agent: Mutt/1.10.1 (2018-07-13) Cc: iommu@lists.linux-foundation.org, Jon.Grimm@amd.com, brijesh.singh@amd.com, linux-kernel@vger.kernel.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi Suravee, On Wed, Oct 28, 2020 at 11:18:24PM +0000, Suravee Suthikulpanit wrote: > AMD IOMMU requires 4k-aligned pages for the event log, the PPR log, > and the completion wait write-back regions. However, when allocating > the pages, they could be part of large mapping (e.g. 2M) page. > This causes #PF due to the SNP RMP hardware enforces the check based > on the page level for these data structures. > > So, fix by calling set_memory_4k() on the allocated pages. > > Fixes: commit c69d89aff393 ("iommu/amd: Use 4K page for completion wait write-back semaphore") > Cc: Brijesh Singh > Signed-off-by: Suravee Suthikulpanit > --- > drivers/iommu/amd/init.c | 22 +++++++++++++++++----- > 1 file changed, 17 insertions(+), 5 deletions(-) > > diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c > index 82e4af8f09bb..75dc30226a7c 100644 > --- a/drivers/iommu/amd/init.c > +++ b/drivers/iommu/amd/init.c > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > > #include > > @@ -672,11 +673,22 @@ static void __init free_command_buffer(struct amd_iommu *iommu) > free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE)); > } > > +static void *__init iommu_alloc_4k_pages(gfp_t gfp, size_t size) > +{ > + void *buf; > + int order = get_order(size); > + > + buf = (void *)__get_free_pages(gfp, order); > + if (!buf) > + return buf; > + return set_memory_4k((unsigned long)buf, (1 << order)) ? NULL : buf; > +} > + Please make the 4k split only if SNP is actually enabled in the system. Regards, Joerg _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu