crypto: ccp - Release dma channels before dmaengine unrgister
authorKoba Ko <koba.ko@canonical.com>
Thu, 1 Sep 2022 14:47:12 +0000 (22:47 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 26 Oct 2022 10:35:25 +0000 (12:35 +0200)
[ Upstream commit 68dbe80f5b510c66c800b9e8055235c5b07e37d1 ]

A warning is shown during shutdown,

__dma_async_device_channel_unregister called while 2 clients hold a reference
WARNING: CPU: 15 PID: 1 at drivers/dma/dmaengine.c:1110 __dma_async_device_channel_unregister+0xb7/0xc0

Call dma_release_channel for occupied channles before dma_async_device_unregister.

Fixes: 54cce8ecb925 ("crypto: ccp - ccp_dmaengine_unregister release dma channels")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Koba Ko <koba.ko@canonical.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/crypto/ccp/ccp-dmaengine.c

index 7d4b4ad..9f753cb 100644 (file)
@@ -641,6 +641,10 @@ static void ccp_dma_release(struct ccp_device *ccp)
        for (i = 0; i < ccp->cmd_q_count; i++) {
                chan = ccp->ccp_dma_chan + i;
                dma_chan = &chan->dma_chan;
+
+               if (dma_chan->client_count)
+                       dma_release_channel(dma_chan);
+
                tasklet_kill(&chan->cleanup_tasklet);
                list_del_rcu(&dma_chan->device_node);
        }
@@ -766,8 +770,8 @@ void ccp_dmaengine_unregister(struct ccp_device *ccp)
        if (!dmaengine)
                return;
 
-       dma_async_device_unregister(dma_dev);
        ccp_dma_release(ccp);
+       dma_async_device_unregister(dma_dev);
 
        kmem_cache_destroy(ccp->dma_desc_cache);
        kmem_cache_destroy(ccp->dma_cmd_cache);