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 C04CE51AFC6 for ; Tue, 22 Sep 2026 13:10:47 +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=1790082648; cv=none; b=oGptnGhn/K2RO9XzByosGh2z5P4gy2qXruI7C79KPaY4bEggOSIUlwJZTAokYJcQExXATmcPnb7wuvt+2ksFIUbkZtaBBuqlWudQkV5Mx8G3lgVRMfKazoFHd/dVfAcICpbJC7SG59NjIDn4SdX1Z6IY3K96jPgoNpjHq9KnSCU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790082648; c=relaxed/simple; bh=y8xpDcUkqgIEezvZv5RCP9BeJqCH19XKvhuSgaaRm6M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cqDjCH+afBjM0kffZDO4N6x5r4zDLhbfA0PW0FZJdNseQNprl23/RbmmTo+sd7iCaUG0Gzphh/0VuNGgiO1oqKQfXHhAEvff5pumQ1xGfpSR/iImq9996qHic6Yzw6Zaj0VziSDui0x9of5Q23J+hufSy6/3bGHAoEh94nGb9/0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Hsp0NVYK; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Hsp0NVYK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7F271F000FF; Tue, 22 Sep 2026 13:10:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790082647; bh=069s09UiimGs0EDd19SlHVtR8Q8ocwORXz2CVOTeFOY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Hsp0NVYKBRYGVy5CowuSrqgfqDuyP3x92vRJlo8UezX62V7ICqk4BSvRvvMr1Dop0 wKr3E+H8Zii9gkuEz+i5WPX2GAXDLQEDZg8UKsXhykvujWS3lG/urvda+pTDb0CQly vhwu1ih0O11gisf9zVhNqRoVbt0e1lp688MoLrD28AT8fLTt3yPRJOe4pA5/YrEUrX 4pBA9jQq+nmH8KUjhslAoorup0gitOy50XiYcjj0kuwxMVKvRdhVe4FU1ng5RvTJyI svW7rOoGYcRWqsJlDYKNXGvEQq49pne/6iGzYiKLXMlaZICJ/Y+QHEBZdM+L5pVEO+ 5qTIwjYY6JC1g== From: Sasha Levin To: stable@vger.kernel.org Cc: Donggeun Yoo , Michael Kelley , Marek Szyprowski , Sasha Levin Subject: [PATCH 6.12.y] swiotlb: use the adjusted address for the highmem page lookup Date: Tue, 22 Sep 2026 09:10:45 -0400 Message-ID: <20260922131045.2409656-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026092244-diocese-pointing-0bdd@gregkh> References: <2026092244-diocese-pointing-0bdd@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Donggeun Yoo [ Upstream commit b7d7914a9ae3097e63d113007e4fb44d33d515b1 ] 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 [ replaced unavailable PhysHighMem(orig_addr) with PageHighMem(pfn_to_page(PFN_DOWN(orig_addr))). ] Signed-off-by: Sasha Levin --- kernel/dma/swiotlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index ffb7b021e2fb9..90651d535a923 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -869,7 +869,6 @@ static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size 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 *dev, phys_addr_t tlb_addr, size_t size size = alloc_size; } - if (PageHighMem(pfn_to_page(pfn))) { + if (PageHighMem(pfn_to_page(PFN_DOWN(orig_addr)))) { + unsigned long pfn = PFN_DOWN(orig_addr); unsigned int offset = orig_addr & ~PAGE_MASK; struct page *page; unsigned int sz = 0; -- 2.53.0