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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2F7E4C433EF for ; Wed, 22 Jun 2022 12:46:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=2c1HhWtDIHsURC5mQ49E1uvCVDZP8Bpo/BagcTZukIw=; b=twcdJ/ChPvmhlvwh5noudko0Bd LMH26rUjx9vn3ojwbhNhyeHllWTufSBYGUFEwW7c//T0iyJhYoBgp80eMS3IVrqVnHq/zxv+qiWIg AFbF7jEJwJmnmm6G1jTWq/x+gOUmtPQMNUaVjnBBt8bIEOogvnsqSPjDli8INIoknkkuYV0ajOhQg gXRfTb+DP+5MKij8GdJcTGsGAxze9YWS7lDr+FSXMCWSzVm7vlTBo4w29vl5xr/FVdrxDwd1O1r9m MuqaUyafBi1F6RBOZGw6dIvr5Nc3hwkNLlOC5ZBrKlM853yFJXqJ5ldBisINtkK3pq8qHvkqo/Zab BDLEpefg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o3zkr-00AMXQ-4p; Wed, 22 Jun 2022 12:46:45 +0000 Received: from 8bytes.org ([2a01:238:4383:600:38bc:a715:4b6d:a889] helo=theia.8bytes.org) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1o3zkf-00AMV1-Bo; Wed, 22 Jun 2022 12:46:35 +0000 Received: by theia.8bytes.org (Postfix, from userid 1000) id 994612D0; Wed, 22 Jun 2022 14:46:26 +0200 (CEST) Date: Wed, 22 Jun 2022 14:46:19 +0200 From: Joerg Roedel To: yf.wang@mediatek.com Cc: Will Deacon , Matthias Brugger , "open list:IOMMU DRIVERS" , open list , "moderated list:ARM/Mediatek SoC support" , "moderated list:ARM/Mediatek SoC support" , wsd_upstream@mediatek.com, Libo Kang , Miles Chen , Yong Wu , Ning Li Subject: Re: [PATCH] iommu/dma: Fix race condition during iova_domain initialization Message-ID: References: <20220530120748.31733-1-yf.wang@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220530120748.31733-1-yf.wang@mediatek.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220622_054633_746599_C1FE7F1A X-CRM114-Status: GOOD ( 23.28 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org Please re-send with Robin Murphy in Cc. On Mon, May 30, 2022 at 08:07:45PM +0800, yf.wang@mediatek.com wrote: > From: Yunfei Wang > > When many devices share the same iova domain, iommu_dma_init_domain() > may be called at the same time. The checking of iovad->start_pfn will > all get false in iommu_dma_init_domain() and both enter init_iova_domain() > to do iovad initialization. > > Fix this by protecting init_iova_domain() with iommu_dma_cookie->mutex. > > Exception backtrace: > rb_insert_color(param1=0xFFFFFF80CD2BDB40, param3=1) + 64 > init_iova_domain() + 180 > iommu_setup_dma_ops() + 260 > arch_setup_dma_ops() + 132 > of_dma_configure_id() + 468 > platform_dma_configure() + 32 > really_probe() + 1168 > driver_probe_device() + 268 > __device_attach_driver() + 524 > __device_attach() + 524 > bus_probe_device() + 64 > deferred_probe_work_func() + 260 > process_one_work() + 580 > worker_thread() + 1076 > kthread() + 332 > ret_from_fork() + 16 > > Signed-off-by: Ning Li > Signed-off-by: Yunfei Wang > --- > drivers/iommu/dma-iommu.c | 17 +++++++++++++---- > 1 file changed, 13 insertions(+), 4 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index 09f6e1c0f9c0..b38c5041eeab 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -63,6 +63,7 @@ struct iommu_dma_cookie { > > /* Domain for flush queue callback; NULL if flush queue not in use */ > struct iommu_domain *fq_domain; > + struct mutex mutex; > }; > > static DEFINE_STATIC_KEY_FALSE(iommu_deferred_attach_enabled); > @@ -309,6 +310,7 @@ int iommu_get_dma_cookie(struct iommu_domain *domain) > if (!domain->iova_cookie) > return -ENOMEM; > > + mutex_init(&domain->iova_cookie->mutex); > return 0; > } > > @@ -549,26 +551,33 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, > } > > /* start_pfn is always nonzero for an already-initialised domain */ > + mutex_lock(&cookie->mutex); > if (iovad->start_pfn) { > if (1UL << order != iovad->granule || > base_pfn != iovad->start_pfn) { > pr_warn("Incompatible range for DMA domain\n"); > - return -EFAULT; > + ret = -EFAULT; > + goto done_unlock; > } > > - return 0; > + ret = 0; > + goto done_unlock; > } > > init_iova_domain(iovad, 1UL << order, base_pfn); > ret = iova_domain_init_rcaches(iovad); > if (ret) > - return ret; > + goto done_unlock; > > /* If the FQ fails we can simply fall back to strict mode */ > if (domain->type == IOMMU_DOMAIN_DMA_FQ && iommu_dma_init_fq(domain)) > domain->type = IOMMU_DOMAIN_DMA; > > - return iova_reserve_iommu_regions(dev, domain); > + ret = iova_reserve_iommu_regions(dev, domain); > + > +done_unlock: > + mutex_unlock(&cookie->mutex); > + return ret; > } > > /** > -- > 2.18.0