From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A026F36D; Wed, 17 Sep 2025 12:36:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758112580; cv=none; b=bn6QF/njnQ1UPpMeb6MYbTOi9Ny1JwdCU7zg7x+1PWaXUgR+BVoFvtDEwbA28M00punRe5kjoMlL6F+ErCpSBEryjqkwjgHGM20CKXqjuymWhyvtiQkR3nFlT9eykjYsR1b6GGywCqUF+omAybU8p6BfsfQqZL6r1dVOOwNbM0E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758112580; c=relaxed/simple; bh=WMXfmWgDnjRe9OLkqWlRk3lLzQGHhGQzn5nZYY8DnEE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JhyqI/NU7u2rZ2HrsTEIuoGO//SuDgAyIruLH+3WjgGYZ1NJtbROxp62FYWL9MNDHuTBCB8yZxbAGJsiDBwM7nVwFHbOEGO4bANlmdSBocLcmtl1JOq2gvo8y3vA4VDPPsJhevoshtiO8jZl6JLQ7QRuuHzt+7eGs4CK9OIg6u4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=r/Ufm+PR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="r/Ufm+PR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B3F08C4CEF0; Wed, 17 Sep 2025 12:36:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1758112580; bh=WMXfmWgDnjRe9OLkqWlRk3lLzQGHhGQzn5nZYY8DnEE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=r/Ufm+PRZKArKuCDVPHcFq8i4Z0gz5+0AKt1JEWJnvT0rwgatj2Tgkc+ceMAc0WFG 3gUV1yCFmYQ0paY4wva3ctta/9yRA54ZjcoOcHqw36Z2PtmJrOX1XUOUOLrjcokbXm bCHQzQBHRKpiAXqaiiDcXhFjMly/arc6kMaqyae8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Baochen Qiang , Marek Szyprowski , Sasha Levin Subject: [PATCH 6.16 006/189] dma-debug: dont enforce dma mapping check on noncoherent allocations Date: Wed, 17 Sep 2025 14:31:56 +0200 Message-ID: <20250917123352.003636148@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250917123351.839989757@linuxfoundation.org> References: <20250917123351.839989757@linuxfoundation.org> User-Agent: quilt/0.68 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 6.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Baochen Qiang [ Upstream commit 7e2368a21741e2db542330b32aa6fdd8908e7cff ] As discussed in [1], there is no need to enforce dma mapping check on noncoherent allocations, a simple test on the returned CPU address is good enough. Add a new pair of debug helpers and use them for noncoherent alloc/free to fix this issue. Fixes: efa70f2fdc84 ("dma-mapping: add a new dma_alloc_pages API") Link: https://lore.kernel.org/all/ff6c1fe6-820f-4e58-8395-df06aa91706c@oss.qualcomm.com # 1 Signed-off-by: Baochen Qiang Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20250828-dma-debug-fix-noncoherent-dma-check-v1-1-76e9be0dd7fc@oss.qualcomm.com Signed-off-by: Sasha Levin --- kernel/dma/debug.c | 48 +++++++++++++++++++++++++++++++++++++++++++- kernel/dma/debug.h | 20 ++++++++++++++++++ kernel/dma/mapping.c | 4 ++-- 3 files changed, 69 insertions(+), 3 deletions(-) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index e43c6de2bce4e..b82399437db03 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -39,6 +39,7 @@ enum { dma_debug_sg, dma_debug_coherent, dma_debug_resource, + dma_debug_noncoherent, }; enum map_err_types { @@ -141,6 +142,7 @@ static const char *type2name[] = { [dma_debug_sg] = "scatter-gather", [dma_debug_coherent] = "coherent", [dma_debug_resource] = "resource", + [dma_debug_noncoherent] = "noncoherent", }; static const char *dir2name[] = { @@ -993,7 +995,8 @@ static void check_unmap(struct dma_debug_entry *ref) "[mapped as %s] [unmapped as %s]\n", ref->dev_addr, ref->size, type2name[entry->type], type2name[ref->type]); - } else if (entry->type == dma_debug_coherent && + } else if ((entry->type == dma_debug_coherent || + entry->type == dma_debug_noncoherent) && ref->paddr != entry->paddr) { err_printk(ref->dev, entry, "device driver frees " "DMA memory with different CPU address " @@ -1581,6 +1584,49 @@ void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, } } +void debug_dma_alloc_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr, + unsigned long attrs) +{ + struct dma_debug_entry *entry; + + if (unlikely(dma_debug_disabled())) + return; + + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->type = dma_debug_noncoherent; + entry->dev = dev; + entry->paddr = page_to_phys(page); + entry->size = size; + entry->dev_addr = dma_addr; + entry->direction = direction; + + add_dma_entry(entry, attrs); +} + +void debug_dma_free_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr) +{ + struct dma_debug_entry ref = { + .type = dma_debug_noncoherent, + .dev = dev, + .paddr = page_to_phys(page), + .dev_addr = dma_addr, + .size = size, + .direction = direction, + }; + + if (unlikely(dma_debug_disabled())) + return; + + check_unmap(&ref); +} + static int __init dma_debug_driver_setup(char *str) { int i; diff --git a/kernel/dma/debug.h b/kernel/dma/debug.h index f525197d3cae6..48757ca13f314 100644 --- a/kernel/dma/debug.h +++ b/kernel/dma/debug.h @@ -54,6 +54,13 @@ extern void debug_dma_sync_sg_for_cpu(struct device *dev, extern void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems, int direction); +extern void debug_dma_alloc_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr, + unsigned long attrs); +extern void debug_dma_free_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr); #else /* CONFIG_DMA_API_DEBUG */ static inline void debug_dma_map_page(struct device *dev, struct page *page, size_t offset, size_t size, @@ -126,5 +133,18 @@ static inline void debug_dma_sync_sg_for_device(struct device *dev, int nelems, int direction) { } + +static inline void debug_dma_alloc_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr, + unsigned long attrs) +{ +} + +static inline void debug_dma_free_pages(struct device *dev, struct page *page, + size_t size, int direction, + dma_addr_t dma_addr) +{ +} #endif /* CONFIG_DMA_API_DEBUG */ #endif /* _KERNEL_DMA_DEBUG_H */ diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 107e4a4d251df..56de28a3b1799 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -712,7 +712,7 @@ struct page *dma_alloc_pages(struct device *dev, size_t size, if (page) { trace_dma_alloc_pages(dev, page_to_virt(page), *dma_handle, size, dir, gfp, 0); - debug_dma_map_page(dev, page, 0, size, dir, *dma_handle, 0); + debug_dma_alloc_pages(dev, page, size, dir, *dma_handle, 0); } else { trace_dma_alloc_pages(dev, NULL, 0, size, dir, gfp, 0); } @@ -738,7 +738,7 @@ void dma_free_pages(struct device *dev, size_t size, struct page *page, dma_addr_t dma_handle, enum dma_data_direction dir) { trace_dma_free_pages(dev, page_to_virt(page), dma_handle, size, dir, 0); - debug_dma_unmap_page(dev, dma_handle, size, dir); + debug_dma_free_pages(dev, page, size, dir, dma_handle); __dma_free_pages(dev, size, page, dma_handle, dir); } EXPORT_SYMBOL_GPL(dma_free_pages); -- 2.51.0