dmaengine: at_hdmac: Protect atchan->status with the channel lock
authorTudor Ambarus <tudor.ambarus@microchip.com>
Tue, 25 Oct 2022 09:02:40 +0000 (12:02 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 16 Nov 2022 08:57:18 +0000 (09:57 +0100)
commit9b69060a725dbc8ee3f3d270279d6b2d9e39079b
treef2ce7c3b8af35902c994f887ad89c4374e07a653
parentee356822618ee86cfab8fac1bec0bf66fb98ea2e
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 <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
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 <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/dma/at_hdmac.c