mbox series

[v3,0/3] UIO_MEM_DMA_COHERENT for cnic/bnx2/bnx2x

Message ID 20240109121458.26475-1-njavali@marvell.com (mailing list archive)
Headers show
Series UIO_MEM_DMA_COHERENT for cnic/bnx2/bnx2x | expand

Message

Nilesh Javali Jan. 9, 2024, 12:14 p.m. UTC 
During bnx2i iSCSI testing we ran into page refcounting issues in the
uio mmaps exported from cnic to the iscsiuio process, and bisected back
to the removal of the __GFP_COMP flag from dma_alloc_coherent calls.

In order to fix these drivers to be able to mmap dma coherent memory via
a uio device, without resorting to hacks and working with an iommu
enabled, introduce a new uio mmap type backed by dma_mmap_coherent.

While converting the uio interface, I also noticed that not all of these
allocations were PAGE_SIZE aligned. Particularly the bnx2/bnx2x status
block mapping was much smaller than any architecture page size, and I
was concerned that it could be unintentionally exposing kernel memory.

v3:
- fix warnings reported by kernel test robot
  and added base commit
v2:
- expose only the dma_addr within uio and cnic.
- Cleanup newly added unions comprising virtual_addr
  and struct device

Chris Leech (3):
  uio: introduce UIO_MEM_DMA_COHERENT type
  cnic,bnx2,bnx2x: use UIO_MEM_DMA_COHERENT
  cnic,bnx2,bnx2x: page align uio mmap allocations

 drivers/net/ethernet/broadcom/bnx2.c          |  2 +
 .../net/ethernet/broadcom/bnx2x/bnx2x_main.c  | 10 +++--
 drivers/net/ethernet/broadcom/cnic.c          | 20 +++++++---
 drivers/net/ethernet/broadcom/cnic.h          |  1 +
 drivers/net/ethernet/broadcom/cnic_if.h       |  1 +
 drivers/uio/uio.c                             | 40 +++++++++++++++++++
 include/linux/uio_driver.h                    |  2 +
 7 files changed, 66 insertions(+), 10 deletions(-)


base-commit: ed340d13aa1db6773667ed4bf907738df203fbda

Comments

Nilesh Javali Jan. 17, 2024, 7:59 a.m. UTC | #1 
A gentle reminder if this patch set can be reviewed.

Thanks,
Nilesh

> -----Original Message-----
> From: Nilesh Javali <njavali@marvell.com>
> Sent: Tuesday, January 9, 2024 5:45 PM
> To: martin.petersen@oracle.com; lduncan@suse.com; cleech@redhat.com
> Cc: linux-scsi@vger.kernel.org; GR-QLogic-Storage-Upstream <GR-QLogic-
> Storage-Upstream@marvell.com>; jmeneghi@redhat.com
> Subject: [PATCH v3 0/3] UIO_MEM_DMA_COHERENT for cnic/bnx2/bnx2x
> 
> During bnx2i iSCSI testing we ran into page refcounting issues in the
> uio mmaps exported from cnic to the iscsiuio process, and bisected back
> to the removal of the __GFP_COMP flag from dma_alloc_coherent calls.
> 
> In order to fix these drivers to be able to mmap dma coherent memory via
> a uio device, without resorting to hacks and working with an iommu
> enabled, introduce a new uio mmap type backed by dma_mmap_coherent.
> 
> While converting the uio interface, I also noticed that not all of these
> allocations were PAGE_SIZE aligned. Particularly the bnx2/bnx2x status
> block mapping was much smaller than any architecture page size, and I
> was concerned that it could be unintentionally exposing kernel memory.
> 
> v3:
> - fix warnings reported by kernel test robot
>   and added base commit
> v2:
> - expose only the dma_addr within uio and cnic.
> - Cleanup newly added unions comprising virtual_addr
>   and struct device
> 
> Chris Leech (3):
>   uio: introduce UIO_MEM_DMA_COHERENT type
>   cnic,bnx2,bnx2x: use UIO_MEM_DMA_COHERENT
>   cnic,bnx2,bnx2x: page align uio mmap allocations
> 
>  drivers/net/ethernet/broadcom/bnx2.c          |  2 +
>  .../net/ethernet/broadcom/bnx2x/bnx2x_main.c  | 10 +++--
>  drivers/net/ethernet/broadcom/cnic.c          | 20 +++++++---
>  drivers/net/ethernet/broadcom/cnic.h          |  1 +
>  drivers/net/ethernet/broadcom/cnic_if.h       |  1 +
>  drivers/uio/uio.c                             | 40 +++++++++++++++++++
>  include/linux/uio_driver.h                    |  2 +
>  7 files changed, 66 insertions(+), 10 deletions(-)
> 
> 
> base-commit: ed340d13aa1db6773667ed4bf907738df203fbda
> --
> 2.23.1