[PATCH resend] dma-debug: Use memory_intersects() directly

From: Kefeng Wang
Date: Thu Jul 22 2021 - 06:48:55 EST


There is already a memory_intersects() helper in sections.h,
use memory_intersects() directly instead of private overlap().

Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---

Resend this patch only.

kernel/dma/debug.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index dadae6255d05..fe6efd181614 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -1064,20 +1064,10 @@ static void check_for_stack(struct device *dev,
}
}

-static inline bool overlap(void *addr, unsigned long len, void *start, void *end)
-{
- unsigned long a1 = (unsigned long)addr;
- unsigned long b1 = a1 + len;
- unsigned long a2 = (unsigned long)start;
- unsigned long b2 = (unsigned long)end;
-
- return !(b1 <= a2 || a1 >= b2);
-}
-
static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len)
{
- if (overlap(addr, len, _stext, _etext) ||
- overlap(addr, len, __start_rodata, __end_rodata))
+ if (memory_intersects(_stext, _etext, addr, len) ||
+ memory_intersects(__start_rodata, __end_rodata, addr, len))
err_printk(dev, NULL, "device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len);
}

--
2.26.2