0a352554da
IOMMUs using ARMv7 short-descriptor format require page tables (level 1 and 2) to be allocated within the first 4GB of RAM, even on 64-bit systems. For level 1/2 pages, ensure GFP_DMA32 is used if CONFIG_ZONE_DMA32 is defined (e.g. on arm64 platforms). For level 2 pages, allocate a slab cache in SLAB_CACHE_DMA32. Note that we do not explicitly pass GFP_DMA[32] to kmem_cache_zalloc, as this is not strictly necessary, and would cause a warning in mm/sl*b.c, as we did not update GFP_SLAB_BUG_MASK. Also, print an error when the physical address does not fit in 32-bit, to make debugging easier in the future. Link: http://lkml.kernel.org/r/20181210011504.122604-3-drinkcat@chromium.org Fixes: ad67f5a6545f ("arm64: replace ZONE_DMA with ZONE_DMA32") Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Hsin-Yi Wang <hsinyi@chromium.org> Cc: Huaisheng Ye <yehs1@lenovo.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sasha Levin <Alexander.Levin@microsoft.com> Cc: Tomasz Figa <tfiga@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yingjoe Chen <yingjoe.chen@mediatek.com> Cc: Yong Wu <yong.wu@mediatek.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.