From patchwork Tue May 11 17:41:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 12251587 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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 13CB3C433B4 for ; Tue, 11 May 2021 17:42:03 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 AF7FE613B6 for ; Tue, 11 May 2021 17:42:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AF7FE613B6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.125862.236926 (Exim 4.92) (envelope-from ) id 1lgWOC-0003s9-SR; Tue, 11 May 2021 17:41:48 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 125862.236926; Tue, 11 May 2021 17:41:48 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lgWOC-0003rU-OL; Tue, 11 May 2021 17:41:48 +0000 Received: by outflank-mailman (input) for mailman id 125862; Tue, 11 May 2021 17:41:47 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lgWOB-0003op-IT for xen-devel@lists.xenproject.org; Tue, 11 May 2021 17:41:47 +0000 Received: from mail.kernel.org (unknown [198.145.29.99]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 677c5b21-4605-4b96-b1f7-2cc429289251; Tue, 11 May 2021 17:41:47 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id CB623613C3; Tue, 11 May 2021 17:41:45 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 677c5b21-4605-4b96-b1f7-2cc429289251 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620754906; bh=/y24nuaxa3ahuPNyDsX+pUzlA7FV7W7+VmIh+phhWv4=; h=From:To:Cc:Subject:Date:From; b=aLZ+AS1gA5cMZ8RVBKoIqDIZcfszquu/ab7Ff6SE7rkRnIPa1yGD2Wv1/kGeFyZ2s KTKehYlE2EUwCF9G4rnoyYlJ7fZKBBdXEwh0VBqARwd8gn0iA0AUJcR8NWIxsiD36S hnENri5ucimFD/OOKF3SQJ3xLPKR7GMFxJr0mH5IYSAhPVEgIJlYKyxepqOeINvD6B hbzLGO4L4D/Vzw2gjBofuadHnoqU0rF5Vn+NF0QYlcYB2fM0CVcCtM2y9eg5oROn8G X2w6XtAJQagQb7QGiiHjRpxbG3HmR9xROVxxsx5qW0OHbSO3sp4gcYF5EfVvEemxZA cpgazArg1UgDA== From: Stefano Stabellini To: xen-devel@lists.xenproject.org Cc: sstabellini@kernel.org, hch@lst.de, linux-kernel@vger.kernel.org, Stefano Stabellini , boris.ostrovsky@oracle.com, jgross@suse.com Subject: [PATCH 2/2] xen/swiotlb: check if the swiotlb has already been initialized Date: Tue, 11 May 2021 10:41:42 -0700 Message-Id: <20210511174142.12742-2-sstabellini@kernel.org> X-Mailer: git-send-email 2.17.1 From: Stefano Stabellini xen_swiotlb_init calls swiotlb_late_init_with_tbl, which fails with -ENOMEM if the swiotlb has already been initialized. Add an explicit check io_tlb_default_mem != NULL at the beginning of xen_swiotlb_init. If the swiotlb is already initialized print a warning and return -EEXIST. On x86, the error propagates. On ARM, we don't actually need a special swiotlb buffer (yet), any buffer would do. So ignore the error and continue. CC: boris.ostrovsky@oracle.com CC: jgross@suse.com Signed-off-by: Stefano Stabellini Reviewed-by: Boris Ostrovsky --- arch/arm/xen/mm.c | 8 +++++++- drivers/xen/swiotlb-xen.c | 5 +++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index 223b1151fd7d..a7e54a087b80 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -138,9 +138,15 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) static int __init xen_mm_init(void) { struct gnttab_cache_flush cflush; + int rc; + if (!xen_swiotlb_detect()) return 0; - xen_swiotlb_init(); + + rc = xen_swiotlb_init(); + /* we can work with the default swiotlb */ + if (rc < 0 && rc != -EEXIST) + return rc; cflush.op = 0; cflush.a.dev_bus_addr = 0; diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 4c89afc0df62..6412d59ce7f8 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -164,6 +164,11 @@ int __ref xen_swiotlb_init(void) int rc = -ENOMEM; char *start; + if (io_tlb_default_mem != NULL) { + printk(KERN_WARNING "Xen-SWIOTLB: swiotlb buffer already initialized\n"); + return -EEXIST; + } + retry: m_ret = XEN_SWIOTLB_ENOMEM; order = get_order(bytes);