Am 10.06.22 um 09:52 schrieb Jiabing Wan:

On 2022/6/10 15:24, Christian König wrote:

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Am 10.06.22 um 09:20 schrieb Wan Jiabing:

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Fix following coccicheck warning: ./drivers/dma-buf/st-dma-fence-unwrap.c:75:39-45: ERROR: reference preceded by free on line 70

Use 'struct dma_fence *' instead of 'typeof(*fences)' to avoid this warning and also fix other 'typeof(*fences)' to make them consistent.

Well that doesn't looks correct to me.

*fence should be valid at this point, why does coccicheck things it is freed?

*fence is valid. Coccicheck reports this because fence is freed. But use 'struct dma_fence *' can avoid this wrong report.

Well in this case that's just a clear NAK.

Using typeof(*var) is perfectly valid and preferred should the type change at some point.

As far as I can see your cocci script is somehow reporting a false warning.

Regards, Christian.

I also grep all code and find it's unusual to use 'typeof' in va_arg, only two files.

grep -R "va_arg("  . | grep 'typeof' ./drivers/dma-buf/st-dma-fence-unwrap.c:                fences[i] = va_arg(valist, typeof(*fences)); ./drivers/dma-buf/st-dma-fence-unwrap.c: dma_fence_put(va_arg(valist, typeof(*fences))); ./lib/test_scanf.c:             typeof(*expect) got = *va_arg(ap, typeof(expect));              \

And other files all use declaration name directly. So I send this patch makes code clearer and fix the wrong warning by the way.

Thanks, Wan Jiabing

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Regards, Christian.

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Fixes: 0c5064fa8d5a ("dma-buf: cleanup dma_fence_unwrap selftest v2") Signed-off-by: Wan Jiabing wanjiabing@vivo.com

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drivers/dma-buf/st-dma-fence-unwrap.c | 4 ++--   1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma-buf/st-dma-fence-unwrap.c b/drivers/dma-buf/st-dma-fence-unwrap.c index 4105d5ea8dde..1137a6d90b32 100644 --- a/drivers/dma-buf/st-dma-fence-unwrap.c +++ b/drivers/dma-buf/st-dma-fence-unwrap.c @@ -56,7 +56,7 @@ static struct dma_fence *mock_array(unsigned int num_fences, ...)         va_start(valist, num_fences);       for (i = 0; i < num_fences; ++i) -        fences[i] = va_arg(valist, typeof(*fences)); +        fences[i] = va_arg(valist, struct dma_fence *);       va_end(valist);         array = dma_fence_array_create(num_fences, fences, @@ -72,7 +72,7 @@ static struct dma_fence *mock_array(unsigned int num_fences, ...)   error_put:       va_start(valist, num_fences);       for (i = 0; i < num_fences; ++i) -        dma_fence_put(va_arg(valist, typeof(*fences))); +        dma_fence_put(va_arg(valist, struct dma_fence *));       va_end(valist);       return NULL;   }