[PATCH v3 0/2] iommu: fix the failure of deferred attach for iommu attach device

[Lianbo Jiang]

This patchset is to fix the failure of deferred attach for iommu attach
device, it includes the following two patches:

[1] [PATCH 1/2] dma-iommu: use static-key to minimize the impact in the fast-path
    This is a prepared patch for the second one, move out the is_kdump_kernel()
    check from iommu_dma_deferred_attach() to iommu_dma_init(), and use the
    static-key in the fast-path to minimize the impact in the normal case.

[2] [PATCH 2/2] iommu: use the __iommu_attach_device() directly for deferred attach
    Move the handling currently in iommu_dma_deferred_attach() into the
    iommu core code so that it can call the __iommu_attach_device()
    directly instead of the iommu_attach_device(). The external interface
    iommu_attach_device() is not suitable for handling this situation.

Changes since v1:
[1] use the __iommu_attach_device() directly for deferred attach
[2] use static-key to minimize the impact in the fast-path

Changes since v2:
[1] remove the underscores for the variable "__deferred_attach", and change
its name to iommu_deferred_attach_enabled [Suggested by Christoph Hellwig]
[2] remove the "do_" from the iommu_do_deferred_attach(), and change its
name to iommu_deferred_attach()
[3] remove the "extern" from the definition of iommu_deferred_attach() in
include/linux/iommu.h

Lianbo Jiang (2):
  dma-iommu: use static-key to minimize the impact in the fast-path
  iommu: use the __iommu_attach_device() directly for deferred attach

 drivers/iommu/dma-iommu.c | 29 +++++++++++------------------
 drivers/iommu/iommu.c     | 10 ++++++++++
 include/linux/iommu.h     |  1 +
 3 files changed, 22 insertions(+), 18 deletions(-)

-- 
2.17.1