On Mon, Feb 24, 2020 at 01:24:04PM +0000, Andreas Tobler wrote:
Hi all,
On 21.02.20 08:39, Greg Kroah-Hartman wrote:
From: Sascha Hauer s.hauer@pengutronix.de
[ Upstream commit 02939cd167095f16328a1bd5cab5a90b550606df ]
The current descriptor is not on any list of the virtual DMA channel. Once sdma_terminate_all() is called when a descriptor is currently in flight then this one is forgotten to be freed. We have to call vchan_terminate_vdesc() on this descriptor to re-add it to the lists. Now that we also free the currently running descriptor we can (and actually have to) remove the current descriptor from its list also for the cyclic case.
Signed-off-by: Sascha Hauer s.hauer@pengutronix.de Reviewed-by: Robin Gong yibin.gong@nxp.com Tested-by: Robin Gong yibin.gong@nxp.com Link: https://lore.kernel.org/r/20191216105328.15198-10-s.hauer@pengutronix.de Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org
drivers/dma/imx-sdma.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index c27e206a764c3..66f1b2ac5cde4 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -760,12 +760,8 @@ static void sdma_start_desc(struct sdma_channel *sdmac) return; } sdmac->desc = desc = to_sdma_desc(&vd->tx);
- /*
* Do not delete the node in desc_issued list in cyclic mode, otherwise* the desc allocated will never be freed in vchan_dma_desc_free_list*/- if (!(sdmac->flags & IMX_DMA_SG_LOOP))
list_del(&vd->node);
- list_del(&vd->node);
sdma->channel_control[channel].base_bd_ptr = desc->bd_phys; sdma->channel_control[channel].current_bd_ptr = desc->bd_phys; @@ -1071,7 +1067,6 @@ static void sdma_channel_terminate_work(struct work_struct *work) spin_lock_irqsave(&sdmac->vc.lock, flags); vchan_get_all_descriptors(&sdmac->vc, &head);
- sdmac->desc = NULL; spin_unlock_irqrestore(&sdmac->vc.lock, flags); vchan_dma_desc_free_list(&sdmac->vc, &head); sdmac->context_loaded = false;
@@ -1080,11 +1075,19 @@ static void sdma_channel_terminate_work(struct work_struct *work) static int sdma_disable_channel_async(struct dma_chan *chan) { struct sdma_channel *sdmac = to_sdma_chan(chan);
- unsigned long flags;
- spin_lock_irqsave(&sdmac->vc.lock, flags);
sdma_disable_channel(chan);
- if (sdmac->desc)
- if (sdmac->desc) {
vchan_terminate_vdesc(&sdmac->desc->vd);sdmac->desc = NULL;- }
- spin_unlock_irqrestore(&sdmac->vc.lock, flags);
return 0; }
This patch breaks our imx6 board with the attached trace. Reverting the patch makes it boot again. I tried also 5.6-rc3 and it booted too. A closer look into imx-sdma.c from 5.6-rc3 showed me some details which might have to be backported as well to make this patch work. I tried a1ff6a07f5a3951fcac84f064a76d1ad79c10e40 and was somehow successful. I still have one trace but the board boots now.
Any insights from the experts?
I've now reverted it from all of the 3 stable trees it endeded up in.
thanks,
greg k-h