mbox series

[v3,0/9] dmaengine: virt-dma related fixes

Message ID 20191216105328.15198-1-s.hauer@pengutronix.de (mailing list archive)
Headers show
Series dmaengine: virt-dma related fixes | expand

Message

Sascha Hauer Dec. 16, 2019, 10:53 a.m. UTC
Several drivers call vchan_dma_desc_free_list() or vchan_vdesc_fini() under
&vc->lock. This is not allowed and the first two patches fix this up. If you
are a DMA driver maintainer, the first two patches are the reason you are on
Cc.

The remaining patches are the original purpose of this series:
The i.MX SDMA driver leaks memory when a currently running descriptor is
aborted. Calling vchan_terminate_vdesc() on it to fix this revealed that
the virt-dma support calls the desc_free with the spin_lock held. This
doesn't work for the SDMA driver because it calls dma_free_coherent in
its desc_free hook. This series aims to fix that up.

Changes since v2:
- change drivers to not call vchan_dma_desc_free_list() under spin_lock
- remove debug message from vchan_dma_desc_free_list()

Changes since v1:
- rebase on v5.5-rc1
- Swap patches 1 and 2 for bisectablity
- Rename desc_aborted to desc_terminated
- Free up terminated descriptors immediately instead of letting them accumulate

Sascha Hauer (9):
  dmaengine: bcm2835: do not call vchan_vdesc_fini() with lock held
  dmaengine: virt-dma: Add missing locking
  dmaengine: virt-dma: remove debug message
  dmaengine: virt-dma: Do not call desc_free() under a spin_lock
  dmaengine: virt-dma: Add missing locking around list operations
  dmaengine: virt-dma: use vchan_vdesc_fini() to free descriptors
  dmaengine: imx-sdma: rename function
  dmaengine: imx-sdma: find desc first in sdma_tx_status
  dmaengine: imx-sdma: Fix memory leak

 drivers/dma/bcm2835-dma.c                     |  5 +--
 .../dma/dw-axi-dmac/dw-axi-dmac-platform.c    |  8 +---
 drivers/dma/imx-sdma.c                        | 37 +++++++++++--------
 drivers/dma/mediatek/mtk-uart-apdma.c         |  3 +-
 drivers/dma/owl-dma.c                         |  3 +-
 drivers/dma/s3c24xx-dma.c                     | 22 +++++------
 drivers/dma/sf-pdma/sf-pdma.c                 |  4 +-
 drivers/dma/sun4i-dma.c                       |  3 +-
 drivers/dma/virt-dma.c                        | 10 ++---
 drivers/dma/virt-dma.h                        | 27 ++++++++------
 10 files changed, 63 insertions(+), 59 deletions(-)

Comments

Peter Ujfalusi Dec. 16, 2019, 11:49 a.m. UTC | #1
On 16/12/2019 12.53, Sascha Hauer wrote:
> Several drivers call vchan_dma_desc_free_list() or vchan_vdesc_fini() under
> &vc->lock. This is not allowed and the first two patches fix this up. If you
> are a DMA driver maintainer, the first two patches are the reason you are on
> Cc.
> 
> The remaining patches are the original purpose of this series:
> The i.MX SDMA driver leaks memory when a currently running descriptor is
> aborted. Calling vchan_terminate_vdesc() on it to fix this revealed that
> the virt-dma support calls the desc_free with the spin_lock held. This
> doesn't work for the SDMA driver because it calls dma_free_coherent in
> its desc_free hook. This series aims to fix that up.

for drivers/dma/virt-dma.* :
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>


> Changes since v2:
> - change drivers to not call vchan_dma_desc_free_list() under spin_lock
> - remove debug message from vchan_dma_desc_free_list()
> 
> Changes since v1:
> - rebase on v5.5-rc1
> - Swap patches 1 and 2 for bisectablity
> - Rename desc_aborted to desc_terminated
> - Free up terminated descriptors immediately instead of letting them accumulate
> 
> Sascha Hauer (9):
>   dmaengine: bcm2835: do not call vchan_vdesc_fini() with lock held
>   dmaengine: virt-dma: Add missing locking
>   dmaengine: virt-dma: remove debug message
>   dmaengine: virt-dma: Do not call desc_free() under a spin_lock
>   dmaengine: virt-dma: Add missing locking around list operations
>   dmaengine: virt-dma: use vchan_vdesc_fini() to free descriptors
>   dmaengine: imx-sdma: rename function
>   dmaengine: imx-sdma: find desc first in sdma_tx_status
>   dmaengine: imx-sdma: Fix memory leak
> 
>  drivers/dma/bcm2835-dma.c                     |  5 +--
>  .../dma/dw-axi-dmac/dw-axi-dmac-platform.c    |  8 +---
>  drivers/dma/imx-sdma.c                        | 37 +++++++++++--------
>  drivers/dma/mediatek/mtk-uart-apdma.c         |  3 +-
>  drivers/dma/owl-dma.c                         |  3 +-
>  drivers/dma/s3c24xx-dma.c                     | 22 +++++------
>  drivers/dma/sf-pdma/sf-pdma.c                 |  4 +-
>  drivers/dma/sun4i-dma.c                       |  3 +-
>  drivers/dma/virt-dma.c                        | 10 ++---
>  drivers/dma/virt-dma.h                        | 27 ++++++++------
>  10 files changed, 63 insertions(+), 59 deletions(-)
> 

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
Vinod Koul Dec. 24, 2019, 6:25 a.m. UTC | #2
On 16-12-19, 11:53, Sascha Hauer wrote:
> Several drivers call vchan_dma_desc_free_list() or vchan_vdesc_fini() under
> &vc->lock. This is not allowed and the first two patches fix this up. If you
> are a DMA driver maintainer, the first two patches are the reason you are on
> Cc.
> 
> The remaining patches are the original purpose of this series:
> The i.MX SDMA driver leaks memory when a currently running descriptor is
> aborted. Calling vchan_terminate_vdesc() on it to fix this revealed that
> the virt-dma support calls the desc_free with the spin_lock held. This
> doesn't work for the SDMA driver because it calls dma_free_coherent in
> its desc_free hook. This series aims to fix that up.

Applied all, thanks