From 90c1b07406f0220c53e9423aa2c74e9798198bb9 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Tue, 25 Oct 2022 12:02:40 +0300 Subject: [PATCH] dmaengine: at_hdmac: Protect atchan->status with the channel lock commit 6e5ad28d16f082efeae3d0bd2e31f24bed218019 upstream. Now that the complete callback call was removed from device_terminate_all(), we can protect the atchan->status with the channel lock. The atomic bitops on atchan->status do not substitute proper locking on the status, as one could still modify the status after the lock was dropped in atc_terminate_all() but before the atomic bitops were executed. Fixes: 078a6506141a ("dmaengine: at_hdmac: Fix deadlocks") Reported-by: Peter Rosin Signed-off-by: Tudor Ambarus Cc: stable@vger.kernel.org Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/ Acked-by: Nicolas Ferre Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com Link: https://lore.kernel.org/r/20221025090306.297886-7-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/at_hdmac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 0b30e30..c30cce9 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -1452,12 +1452,12 @@ static int atc_terminate_all(struct dma_chan *chan) list_splice_tail_init(&atchan->queue, &atchan->free_list); list_splice_tail_init(&atchan->active_list, &atchan->free_list); - spin_unlock_irqrestore(&atchan->lock, flags); - clear_bit(ATC_IS_PAUSED, &atchan->status); /* if channel dedicated to cyclic operations, free it */ clear_bit(ATC_IS_CYCLIC, &atchan->status); + spin_unlock_irqrestore(&atchan->lock, flags); + return 0; } -- 2.7.4