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 9B1675650E4; Wed, 30 Sep 2026 17:47:26 +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=1790790447; cv=none; b=jV/zGsj503ACzhTWPzB1DNJYXAB8EWFwCJW5nzzrG+yAiXs6qltp14qfpxYxN6XxLoiWpkt3sVqle4RRM+Bm3Vr9bV0ulTYAgs2oQcWMWPKnssK3OinyoD67w1cKECpA3aPp1xj3fLBpZT3fqA2q2OUI2Y1I3z/5xAj8+z4JTD8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790790447; c=relaxed/simple; bh=U8CvwmzTlgHDd/Bw4iQYpQ8kSx45AhCFnbmIe5oW/j4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PsxXq35C895ufkkFvLADAikuyOXlcQinJGOm5bnLCfWIk2qiSs+QS6oHVWP2aZB33hb4bdL5D24mZO5BByxtMJ3PFom6I/jA84Wk8Fg01uSAYKJBcngzWHpxrvEeV8fapjn9DZ/tIBniYmArs1Y0rfClSFPNhc9gi4o8c8xaHjM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Z0y+eQPH; 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="Z0y+eQPH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00D9F1F000FF; Wed, 30 Sep 2026 17:47:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790790446; bh=xSmr1blbC80JvRpBGIi7E8BheQ7r7+/PL0gvc8ZvhSM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Z0y+eQPHF0YiHqBoIdqmHfBSCDrb3Zy0ojJfoBHQgp9ToppeQx35TXl3ubB1B61hv cbqfaanIY5mkPekrAlBqDHzWP6zxP5OfcmvHefePiIpygluzkaQc883U2EO2XdFEQ4 RzG6BJtQds2XbX183G0TtXNcXFlkIe3oLBxc79Pw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Donggeun Yoo , Michael Kelley , Marek Szyprowski , Sasha Levin Subject: [PATCH 6.12 788/877] swiotlb: use the adjusted address for the highmem page lookup Date: Wed, 30 Sep 2026 17:28:19 +0200 Message-ID: <20260930152431.717895088@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152414.738996857@linuxfoundation.org> References: <20260930152414.738996857@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ 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 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 (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;