| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20250828-dma-debug-fix-noncoherent-dma-check-v1-1-76e9be0dd7fc@oss.qualcomm.com>
Date: Thu, 28 Aug 2025 16:17:33 +0800
From: Baochen Qiang <baochen.qiang@....qualcomm.com>
To: Marek Szyprowski <m.szyprowski@...sung.com>,
Robin Murphy <robin.murphy@....com>,
Thomas Bogendoerfer <tsbogend@...ha.franken.de>
Cc: iommu@...ts.linux.dev, linux-kernel@...r.kernel.org,
Baochen Qiang <baochen.qiang@....qualcomm.com>
Subject: [PATCH] dma-debug: don't enforce dma mapping check on noncoherent
allocations
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 <baochen.qiang@....qualcomm.com>
---
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 e43c6de2bce4e7d3e58f8d9601a7637d8f6da767..b82399437db03116a396c7d1cebd16b2e1af98c3 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 f525197d3cae605aa7e0499eb2ca6f1ae134ec93..48757ca13f31403f58090e1015de828893b8f94f 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 107e4a4d251df65fb86a1d7302261c31138061b7..56de28a3b1799f7c18f7e3f8e5ecd438c5748677 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);
---
base-commit: 95bf875b89b48a95a82aca922eeaf19d52543028
change-id: 20250828-dma-debug-fix-noncoherent-dma-check-8e6915d58494
Best regards,
--
Baochen Qiang <baochen.qiang@....qualcomm.com>
Powered by blists - more mailing lists