[PATCH 0/2] CMA: remove unsupported gfp mask parameter

Marek Szyprowski m.szyprowski at samsung.com
Mon Jul 9 22:19:54 AEST 2018


Dear All,

The CMA related functions cma_alloc() and dma_alloc_from_contiguous()
have gfp mask parameter, but sadly they only support __GFP_NOWARN flag.
This gave their users a misleading feeling that any standard memory
allocation flags are supported, what resulted in the security issue when
caller have set __GFP_ZERO flag and expected the buffer to be cleared.

This patchset changes gfp_mask parameter to a simple boolean no_warn
argument, which covers all the underlaying code supports.

This patchset is a result of the following discussion:
https://patchwork.kernel.org/patch/10461919/

Best regards
Marek Szyprowski
Samsung R&D Institute Poland


Patch summary:

Marek Szyprowski (2):
  mm/cma: remove unsupported gfp_mask parameter from cma_alloc()
  dma: remove unsupported gfp_mask parameter from
    dma_alloc_from_contiguous()

 arch/arm/mm/dma-mapping.c                  | 5 +++--
 arch/arm64/mm/dma-mapping.c                | 4 ++--
 arch/powerpc/kvm/book3s_hv_builtin.c       | 2 +-
 arch/xtensa/kernel/pci-dma.c               | 2 +-
 drivers/iommu/amd_iommu.c                  | 2 +-
 drivers/iommu/intel-iommu.c                | 3 ++-
 drivers/s390/char/vmcp.c                   | 2 +-
 drivers/staging/android/ion/ion_cma_heap.c | 2 +-
 include/linux/cma.h                        | 2 +-
 include/linux/dma-contiguous.h             | 4 ++--
 kernel/dma/contiguous.c                    | 6 +++---
 kernel/dma/direct.c                        | 3 ++-
 mm/cma.c                                   | 8 ++++----
 mm/cma_debug.c                             | 2 +-
 14 files changed, 25 insertions(+), 22 deletions(-)

-- 
2.17.1



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