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The error path has to set nb_desc to > the number of descriptors allocated so far, otherwise pxad_free_desc() > would free entries that were never allocated. > > Fixes: 69050f8d6d075 ("treewide: Replace kmalloc with kmalloc_obj for non-scalar types") > Assisted-by: Claude:claude-opus-5 > Signed-off-by: Sascha Hauer > --- Reviewed-by: Frank Li > pxad_alloc_desc() was converted from > > kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc), GFP_NOWAIT) > > to kzalloc_flex(). hw_desc[] is annotated with __counted_by(nb_desc), so > __alloc_flex() now initializes sw_desc->nb_desc to nb_hw_desc itself. > The loop below it still increments nb_desc for every descriptor it > allocates though, so nb_desc ends up being twice the number of > descriptors that are actually there. > > Drop the now redundant increment. The error path has to set nb_desc to > the number of descriptors allocated so far, otherwise pxad_free_desc() > would free entries that were never allocated. > --- > drivers/dma/pxa_dma.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c > index fa2ee0b3e09f8..8252d27be8c3c 100644 > --- a/drivers/dma/pxa_dma.c > +++ b/drivers/dma/pxa_dma.c > @@ -752,10 +752,11 @@ pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc) > dev_err(&chan->vc.chan.dev->device, > "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n", > __func__, i, sw_desc->desc_pool); > + /* Only the descriptors below i have been allocated */ > + sw_desc->nb_desc = i; > goto err; > } > > - sw_desc->nb_desc++; > sw_desc->hw_desc[i] = desc; > > if (i == 0) > > --- > base-commit: 8d3ae59288f1e7d58d76558a6ee96d533bc5019f > change-id: 20260817-dmaengine-pxa-64152bb34313 > > Best regards, > -- > Sascha Hauer >