The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
Possible dependencies:
6ba826cbb57d ("dmaengine: at_hdmac: Free the memset buf without holding the chan lock")
06988949df8c ("dmaengine: at_hdmac: Fix concurrency over descriptor")
078a6506141a ("dmaengine: at_hdmac: Fix deadlocks")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 6ba826cbb57d675f447b59323204d1473bbd5593 Mon Sep 17 00:00:00 2001
From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
Date: Tue, 25 Oct 2022 12:02:43 +0300
Subject: [PATCH] dmaengine: at_hdmac: Free the memset buf without holding the
chan lock
There's no need to hold the channel lock when freeing the memset buf, as
the operation has already completed. Free the memset buf without holding
the channel lock.
Fixes: 4d112426c344 ("dmaengine: hdmac: Add memset capabilities")
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@xxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20221025090306.297886-10-tudor.ambarus@xxxxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 2012ecc57826..0fb44f622d35 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -462,13 +462,6 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
if (!atc_chan_is_cyclic(atchan))
dma_cookie_complete(txd);
- /* If the transfer was a memset, free our temporary buffer */
- if (desc->memset_buffer) {
- dma_pool_free(atdma->memset_pool, desc->memset_vaddr,
- desc->memset_paddr);
- desc->memset_buffer = false;
- }
-
/* Remove transfer node from the active list. */
list_del_init(&desc->desc_node);
spin_unlock_irqrestore(&atchan->lock, flags);
@@ -487,6 +480,13 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
/* add myself to free_list */
list_add(&desc->desc_node, &atchan->free_list);
spin_unlock_irqrestore(&atchan->lock, flags);
+
+ /* If the transfer was a memset, free our temporary buffer */
+ if (desc->memset_buffer) {
+ dma_pool_free(atdma->memset_pool, desc->memset_vaddr,
+ desc->memset_paddr);
+ desc->memset_buffer = false;
+ }
}
/**
