> 2026年6月26日 20:33，Christian König <[email protected]> 写道： > > On 6/26/26 14:18, WenTao Liang wrote: >> dma_fence_enable_sw_signaling acquires an extra reference on each chain >> fence. The error unwind loop calls dma_fence_put only once per >> chain/fence without first signaling the fence to trigger the callback >> that releases the signaling reference. This prevents the chain fence kref >> from reaching 0, permanently leaking the chain and its contained fence. >> >> Cc: [email protected] <mailto:[email protected]> >> Fixes: dc2f7e67a28a ("dma-buf: Exercise dma-fence-chain under selftests") > > Please drop that, this is a minor issue in a unit test and not anything which > needs backporting. > >> Signed-off-by: WenTao Liang <[email protected]> >> --- >> drivers/dma-buf/st-dma-fence-chain.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/dma-buf/st-dma-fence-chain.c >> b/drivers/dma-buf/st-dma-fence-chain.c >> index 821023dd34df..7dc18e294387 100644 >> --- a/drivers/dma-buf/st-dma-fence-chain.c >> +++ b/drivers/dma-buf/st-dma-fence-chain.c >> @@ -152,7 +152,10 @@ static int fence_chains_init(struct fence_chains *fc, >> unsigned int count, >> >> unwind: >> for (i = 0; i < count; i++) { >> - dma_fence_put(fc->fences[i]); >> + if (fc->fences[i]) { >> + dma_fence_signal(fc->fences[i]); >> + dma_fence_put(fc->fences[i]); >> + } > > The usual text book idiom for such cleanup cases is: > > while (i--) { > dma_fence_signal(fc->fences[i]); > dma_fence_put(fc->chains[i]); > } > > Additional to that we need a different error handling target for the case > that the mock_chain() allocation fails (or just do another dma_fence_put > there). > > Regards, > Christian. > >> dma_fence_put(fc->chains[i]); >> } >> kvfree(fc->fences);
Hi Christian, Understood. Since this is only a minor issue in a unit test and does not affect production code, I agree that it does not need backporting to stable. I'll drop this patch. Thanks for your review. Best regards, WenTao Liang
