linux-kernel - use of dma_direct_set_offset in (allwinner) drivers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 3 Nov 2020 10:55:38 +0100
From:   Christoph Hellwig <hch@....de>
To:     Maxime Ripard <mripard@...nel.org>, Chen-Yu Tsai <wens@...e.org>,
        Yong Deng <yong.deng@...ewell.com>,
        Paul Kocialkowski <paul.kocialkowski@...tlin.com>
Cc:     dri-devel@...ts.freedesktop.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        iommu@...ts.linux-foundation.org, linux-media@...r.kernel.org,
        devel@...verdev.osuosl.org
Subject: use of dma_direct_set_offset in (allwinner) drivers

Hi all,

Linux 5.10-rc1 switched from having a single dma offset in struct device
to a set of DMA ranges, and introduced a new helper to set them,
dma_direct_set_offset.

This in fact surfaced that a bunch of drivers that violate our layering
and set the offset from drivers, which meant we had to reluctantly
export the symbol to set up the DMA range.

The drivers are:

drivers/gpu/drm/sun4i/sun4i_backend.c

  This just use dma_direct_set_offset as a fallback.  Is there any good
  reason to not just kill off the fallback?

drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c

  Same as above.

drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c

  This driver unconditionally sets the offset.  Why can't we do this
  in the device tree?

drivers/staging/media/sunxi/cedrus/cedrus_hw.c

  Same as above.