From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 F30C7538D94; Wed, 23 Sep 2026 14:46:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174762; cv=none; b=E0oR/p+S7jh1e9g1sstCzX9TikmUru8hkYVc9u8Y0O6PkWUYx9TYCttG2+Kq8rv5FbKKACCprsKhyXEURDfUpT04Uy+zaXHpVSzTBiH1RcBorAe0fnTKTfblP+7kePDD/Ddiou/HqJe1GjQeitqtZR5PW7nqYL62jUQc04cPX0o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174762; c=relaxed/simple; bh=oIPjjwBa68rlXYMeFnIF2F/vRO5Jwj4nSubVkRo0Nrk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SLLHGK8r4ypzKD2kVHo+5hPWOy0zT9BIQCv6kSnHlui0taWzPr6ktNBHlyEVLPLZmwgnlRPQW85ixGXCT0rdAviPGqt5DysZxXvAjNZgsk4hJuz2apvOdv76KZPiPmyh6ZtI2KylkQ8vbLvyYbMMAIPu0y/ljnrAZem7Tfgho4Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Bvq94PTM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Bvq94PTM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 394051F000FF; Wed, 23 Sep 2026 14:46:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790174760; bh=jYyoUH3B09NUSU3fwo8HolaFm36YhZ1lRQsxBKHZAu8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Bvq94PTMEgvWnYCJuG+LiAm67MRRfg3O/SOj2F1r0OiSBVXYkPkdvmwcWZ167f7R4 ZGdKXgqkdoLv8OUTAKcob5IHLzaDmS2AoVV0Zsntl/rAcJM74/vzGtOuisnEij6Xd3 oOvN7WLQa0tgp9eW0pRTzFy+BSdSHXLGnVERNmuo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Donggeun Yoo , Michael Kelley , Marek Szyprowski Subject: [PATCH 6.18 218/398] swiotlb: use the adjusted address for the highmem page lookup Date: Wed, 23 Sep 2026 16:04:52 +0200 Message-ID: <20260923140649.074022546@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140643.441954610@linuxfoundation.org> References: <20260923140643.441954610@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Donggeun Yoo commit b7d7914a9ae3097e63d113007e4fb44d33d515b1 upstream. swiotlb_bounce() reads the page frame number from the slot's recorded orig_addr, then advances orig_addr by tlb_offset to reach the address the caller asked about. The highmem branch mixes the two: the offset within the page comes from the adjusted address, the page from the value before it. Once the adjustment crosses a page boundary the pair no longer describes one location, and the whole copy lands one page below the intended one for a positive tlb_offset, one above for a negative one. DMA_FROM_DEVICE writes the device data over the wrong page and leaves the intended one stale, DMA_TO_DEVICE feeds the device from a page the mapping may not cover. Partial syncs through dma_sync_single_range_for_*() are what make tlb_offset non-zero. The branch test is picked the same way, so a slot recorded in lowmem can be adjusted into highmem and the lowmem path then hands a highmem address to phys_to_virt(). Take both from orig_addr once it is final and keep pfn in the branch that uses it. PhysHighMem() asks the question straight from the address, as dma-debug already does. Fixes: 5f89468e2f06 ("swiotlb: manipulate orig_addr when tlb_addr has offset") Cc: stable@vger.kernel.org Signed-off-by: Donggeun Yoo Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20260905084210.148255-1-donggeunyoo.kernel@gmail.com Signed-off-by: Marek Szyprowski Signed-off-by: Greg Kroah-Hartman --- kernel/dma/swiotlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -869,7 +869,6 @@ static void swiotlb_bounce(struct device int index = (tlb_addr - mem->start) >> IO_TLB_SHIFT; phys_addr_t orig_addr = mem->slots[index].orig_addr; size_t alloc_size = mem->slots[index].alloc_size; - unsigned long pfn = PFN_DOWN(orig_addr); unsigned char *vaddr = mem->vaddr + tlb_addr - mem->start; int tlb_offset; @@ -899,7 +898,8 @@ static void swiotlb_bounce(struct device size = alloc_size; } - if (PageHighMem(pfn_to_page(pfn))) { + if (PhysHighMem(orig_addr)) { + unsigned long pfn = PFN_DOWN(orig_addr); unsigned int offset = orig_addr & ~PAGE_MASK; struct page *page; unsigned int sz = 0;