From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout2.w1.samsung.com (mailout2.w1.samsung.com [210.118.77.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 08D1611713 for ; Mon, 23 Feb 2026 07:36:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.118.77.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771832189; cv=none; b=BDPjifiNgCieesPdQGC9nw5NbiSDCH6Da0qiibBJza17YMdLb+/3qAw9TgBzvCl/+sTKspvtYLsgxRs632wXTtPr72mhJUCd+vl574HLid4dFoJZzjcynAh/InfbTe08SgZ9o68D1RkMS+1qDgOg9RsypBX2KL176YxQkfVKdpA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771832189; c=relaxed/simple; bh=WIH0B/pATi1JcvK2MOwlnqqmM90GQFjIRygcVbshkv4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:From:In-Reply-To: Content-Type:References; b=Z35TdD1s8G7nHXbSFfp1mebKFNMqe3vzevdwndw/IrtE2zizPTttriLad6K8jNcrJrxrQzICdqne4Tx1hh8EregSuhJS+HyvhGbqZjghMV062ydX/6Qghxnn1BsIJmXh27kbPdgtA+z0bwBfs7Fvn8RHXprkHvRZKQSnje/RonI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com; spf=pass smtp.mailfrom=samsung.com; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b=b02dNdHU; arc=none smtp.client-ip=210.118.77.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=samsung.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="b02dNdHU" Received: from eucas1p1.samsung.com (unknown [182.198.249.206]) by mailout2.w1.samsung.com (KnoxPortal) with ESMTP id 20260223073625euoutp02c01ce3ef74750192fb86fbc9d49350b4~Wz-wV4oLi1688616886euoutp02J for ; Mon, 23 Feb 2026 07:36:25 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20260223073625euoutp02c01ce3ef74750192fb86fbc9d49350b4~Wz-wV4oLi1688616886euoutp02J DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1771832185; bh=siN3nhK4xAmEu87Kj9QrjRdSzOGuHIv1AjOJb1pKcic=; h=Date:Subject:To:Cc:From:In-Reply-To:References:From; b=b02dNdHUYBiLCPloSEBrF9FXGv74V6WONMKZBKkTmE3kzB1zkV7jZXXlSYlIZPiSH C0ytk8MupDch9LUepNlgIlFGgDNbwDsYqGeJLPZ/+4Me/SWJ0xufHxGVXFPFEVHwQ/ fFZWBbcz5mtjagYdQcphswhuDcEP88YoLMjMjP48= Received: from eusmtip1.samsung.com (unknown [203.254.199.221]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20260223073624eucas1p2e4f7a971ee7f9761b90aef9b901ed185~Wz-wJtp8J2724727247eucas1p2N; Mon, 23 Feb 2026 07:36:24 +0000 (GMT) Received: from [106.210.134.192] (unknown [106.210.134.192]) by eusmtip1.samsung.com (KnoxPortal) with ESMTPA id 20260223073624eusmtip1180bf9a1dd8cd8fdbdc15862f619f56b~Wz-vY9DTK1262412624eusmtip1b; Mon, 23 Feb 2026 07:36:23 +0000 (GMT) Message-ID: Date: Mon, 23 Feb 2026 08:36:23 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Betterbird (Windows) Subject: Re: [PATCH v3] sparc: Fix page alignment in dma mapping To: stian@itx.no, sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "David S. Miller" , Andreas Larsson , Leon Romanovsky Content-Language: en-US From: Marek Szyprowski In-Reply-To: <20260218120056.3366-2-stian@itx.no> Content-Transfer-Encoding: 7bit X-CMS-MailID: 20260223073624eucas1p2e4f7a971ee7f9761b90aef9b901ed185 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20260218120247eucas1p2a4201e330790c4f8a9c846fd6dbdf889 X-EPHeader: CA X-CMS-RootMailID: 20260218120247eucas1p2a4201e330790c4f8a9c846fd6dbdf889 References: <20260218120056.3366-2-stian@itx.no> On 18.02.2026 13:00, stian@itx.no wrote: > From: Stian Halseth > > 'phys' may include an offset within the page, while 'base_paddr' is already > page-aligned. This caused incorrect DMA mapping in dma_4u_map_phys and > dma_4v_map_phys. > > Fix both functions by masking phys with IO_PAGE_MASK or subtracting the > page offset, covering both generic SPARC code and sun4v. > > Fixes: 38c0d0ebf520 ("sparc: Use physical address DMA mapping") > Reported-by: Stian Halseth > Closes: https://protect2.fireeye.com/v1/url?k=7ae4b721-1b6fa20e-7ae53c6e-74fe485cbfe7-9b567c88f1f84114&q=1&e=1e25ada4-9521-4797-a8c9-57719379250d&u=https%3A%2F%2Fgithub.com%2Fsparclinux%2Fissues%2Fissues%2F75 > Suggested-by: Marek Szyprowski > Signed-off-by: Stian Halseth Applied to dma-mapping-fixes branch with slightly adjusted commit description (to match v3 changes). Thanks! > --- > Changelog: > v3: > - Use IO_PAGE_MASK for alignment in both dma_4u_map_phys and dma_4v_map_phys > - Align phys before the loop in pci_sun4v.c > - Drop masking inside iommu_batch_add() > > v2: https://lore.kernel.org/all/20260217171104.5643-3-stian@itx.no/ > - Add Fixes tag > - Add Closes tag > - Trim commit message to 80-column lines > - Remove newlines > - Subject: Remove the "iommu/pci_sun4v:" (generic sparc patch, not specific to sun4v) > > v1: https://lore.kernel.org/all/20260217150350.3541-2-stian@itx.no/ > --- > arch/sparc/kernel/iommu.c | 2 ++ > arch/sparc/kernel/pci_sun4v.c | 2 ++ > 2 files changed, 4 insertions(+) > > diff --git a/arch/sparc/kernel/iommu.c b/arch/sparc/kernel/iommu.c > index 46ef88bc9c26..7613ab0ffb89 100644 > --- a/arch/sparc/kernel/iommu.c > +++ b/arch/sparc/kernel/iommu.c > @@ -312,6 +312,8 @@ static dma_addr_t dma_4u_map_phys(struct device *dev, phys_addr_t phys, > if (direction != DMA_TO_DEVICE) > iopte_protection |= IOPTE_WRITE; > > + phys &= IO_PAGE_MASK; > + > for (i = 0; i < npages; i++, base++, phys += IO_PAGE_SIZE) > iopte_val(*base) = iopte_protection | phys; > > diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c > index 791f0a76665f..58ca4148f86b 100644 > --- a/arch/sparc/kernel/pci_sun4v.c > +++ b/arch/sparc/kernel/pci_sun4v.c > @@ -410,6 +410,8 @@ static dma_addr_t dma_4v_map_phys(struct device *dev, phys_addr_t phys, > > iommu_batch_start(dev, prot, entry); > > + phys &= IO_PAGE_MASK; > + > for (i = 0; i < npages; i++, phys += IO_PAGE_SIZE) { > long err = iommu_batch_add(phys, mask); > if (unlikely(err < 0L)) Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland