From: Xiaomeng Tong xiam0nd.tong@gmail.com
stable inclusion from stable-v5.10.113 commit 358a3846f6a950b8db803262e74081ad4ab235d4 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 206680c4e46b62fd8909385e0874a36952595b85 upstream.
The bug is here: __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
The list iterator 'desc' will point to a bogus position containing HEAD if the list is empty or no element is found. To avoid dev_dbg() prints a invalid address, use a new variable 'iter' as the list iterator, while use the origin variable 'desc' as a dedicated pointer to point to the found element.
Cc: stable@vger.kernel.org Fixes: 82e2424635f4c ("dmaengine: xdmac: fix print warning on dma_addr_t variable") Signed-off-by: Xiaomeng Tong xiam0nd.tong@gmail.com Link: https://lore.kernel.org/r/20220327061154.4867-1-xiam0nd.tong@gmail.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com --- drivers/dma/at_xdmac.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 90afba0b36fe..47552db6b8dc 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -1390,7 +1390,7 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie, { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); - struct at_xdmac_desc *desc, *_desc; + struct at_xdmac_desc *desc, *_desc, *iter; struct list_head *descs_list; enum dma_status ret; int residue, retry; @@ -1505,11 +1505,13 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie, * microblock. */ descs_list = &desc->descs_list; - list_for_each_entry_safe(desc, _desc, descs_list, desc_node) { - dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg); - residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth; - if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda) + list_for_each_entry_safe(iter, _desc, descs_list, desc_node) { + dwidth = at_xdmac_get_dwidth(iter->lld.mbr_cfg); + residue -= (iter->lld.mbr_ubc & 0xffffff) << dwidth; + if ((iter->lld.mbr_nda & 0xfffffffc) == cur_nda) { + desc = iter; break; + } } residue += cur_ubc << dwidth;