The merge commit log tells (dma-mapping: zero memory returned from dma_alloc_* and deprecating the dma_zalloc_coherent). I used this commit just want to say that dma_alloc_coherent has zeroed the allocated memory. Sorry for this mistake.
Maybe this commit 518a2f1925c3("dma-mapping: zero memory returned from dma_alloc_*") is correct.
Christophe Leroy christophe.leroy@c-s.fr 於 2019年6月28日週五 下午4:59寫道：
Le 28/06/2019 à 04:50, Fuqian Huang a écrit :
In commit af7ddd8a627c ("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"), dma_alloc_coherent has already zeroed the memory. So memset is not needed.
You are refering to a merge commit, is that correct ?
I can't see anything related in that commit, can you please pinpoint it ?
As far as I can see, on powerpc the memory has always been zeroized (since 2005 at least).
Christophe
Signed-off-by: Fuqian Huang huangfq.daxian@gmail.com
sound/ppc/pmac.c | 1 - 1 file changed, 1 deletion(-)
diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c index 1b11e53f6a62..1ab12f4f8631 100644 --- a/sound/ppc/pmac.c +++ b/sound/ppc/pmac.c @@ -56,7 +56,6 @@ static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, i if (rec->space == NULL) return -ENOMEM; rec->size = size;
memset(rec->space, 0, rsize); rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space); rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space);