From f71ef686f913c8e9771a54466a76d653b83cd3dd Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Sun, 27 Sep 2026 11:03:24 +0200 Subject: [PATCH] dmaengine: ste_dma40: Fix DMA registration unwind d40_dmaengine_init() registers DMAengine devices using devres-managed unregister actions. If probe fails after one of those registrations, the DMAengine devices stay visible until devres unwinds after d40_probe() returns. The channel tasklets are also initialized before each DMAengine device is registered. An interrupt can therefore have queued a tasklet by the time a later registration step fails, but unregistering the DMAengine devices does not drain that tasklet before probe-owned storage is released. Add tasklet cleanup actions to the DMAengine registration devres group. Install each action before publishing its DMAengine device. If action registration fails, those tasklets have never been exposed and cannot have been scheduled, so use devm_add_action() without immediate reset cleanup. On later failure, free the IRQ before releasing the group so no new tasklets can be scheduled, then unregister the DMAengine devices and drain their tasklets before freeing the remaining probe resources. Keep the managed registrations and cleanup actions in place on successful probe by removing only the temporary group markers. Fixes: 42ae6f1695be ("dmaengine: ste_dma40: Remove platform data") Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/dmaengine/20260819225215.5EA2F1F000E9@smtp.kernel.org/ Assisted-by: LLM Signed-off-by: Linus Walleij Reviewed-by: Frank Li Link: https://patch.msgid.link/20260927-dma40-fixes-v7-11-89f595e8851d@kernel.org Signed-off-by: Vinod Koul --- drivers/dma/ste_dma40.c | 45 +++++++++++++++++++++++++++++++++++++++-- 1 file changed, 43 insertions(+), 2 deletions(-) diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c index 57b60cf7194c..ee6542491279 100644 --- a/drivers/dma/ste_dma40.c +++ b/drivers/dma/ste_dma40.c @@ -3034,6 +3034,18 @@ static void __init d40_chan_init(struct d40_base *base, struct dma_device *dma, } } +static void d40_kill_tasklets(void *data) +{ + struct dma_device *dma = data; + struct d40_chan *d40c; + struct dma_chan *chan; + + list_for_each_entry(chan, &dma->channels, device_node) { + d40c = container_of(chan, struct d40_chan, chan); + tasklet_kill(&d40c->tasklet); + } +} + static void d40_ops_init(struct d40_base *base, struct dma_device *dev) { if (dma_has_cap(DMA_SLAVE, dev->cap_mask)) { @@ -3080,6 +3092,11 @@ static int __init d40_dmaengine_init(struct d40_base *base, d40_ops_init(base, &base->dma_slave); + err = devm_add_action(base->dev, d40_kill_tasklets, + &base->dma_slave); + if (err) + goto exit; + err = dmaenginem_async_device_register(&base->dma_slave); if (err) { @@ -3095,6 +3112,11 @@ static int __init d40_dmaengine_init(struct d40_base *base, d40_ops_init(base, &base->dma_memcpy); + err = devm_add_action(base->dev, d40_kill_tasklets, + &base->dma_memcpy); + if (err) + goto exit; + err = dmaenginem_async_device_register(&base->dma_memcpy); if (err) { @@ -3112,6 +3134,12 @@ static int __init d40_dmaengine_init(struct d40_base *base, dma_cap_set(DMA_CYCLIC, base->dma_both.cap_mask); d40_ops_init(base, &base->dma_both); + + err = devm_add_action(base->dev, d40_kill_tasklets, + &base->dma_both); + if (err) + goto exit; + err = dmaenginem_async_device_register(&base->dma_both); if (err) { @@ -3709,6 +3737,7 @@ static int __init d40_probe(struct platform_device *pdev) struct d40_base *base; struct resource *res; struct resource res_lcpa; + void *dmaenginem_reg_group; int num_reserved_chans; u32 val; int ret; @@ -3839,20 +3868,32 @@ static int __init d40_probe(struct platform_device *pdev) d40_err(dev, "No IRQ defined\n"); goto destroy_cache; } + + dmaenginem_reg_group = devres_open_group(dev, NULL, GFP_KERNEL); + if (!dmaenginem_reg_group) { + ret = -ENOMEM; + goto release_irq; + } + ret = d40_dmaengine_init(base, num_reserved_chans); if (ret) - goto release_irq; + goto release_dmaenginem; ret = of_dma_controller_register(np, d40_xlate, NULL); if (ret) { dev_err(dev, "could not register of_dma_controller\n"); - goto release_irq; + goto release_dmaenginem; } + devres_remove_group(dev, dmaenginem_reg_group); dev_info(base->dev, "initialized\n"); return 0; + release_dmaenginem: + free_irq(base->irq, base); + devres_release_group(dev, dmaenginem_reg_group); + goto destroy_cache; release_irq: free_irq(base->irq, base); destroy_cache: