Commits
Will Deacon committed f71da467194
iommu/io-pgtable-arm: Remove redundant call to io_pgtable_tlb_sync()
Commit b6b65ca20bc9 ("iommu/io-pgtable-arm: Add support for non-strict
mode") added an unconditional call to io_pgtable_tlb_sync() immediately
after the case where we replace a block entry with a table entry during
an unmap() call. This is redundant, since the IOMMU API will call
iommu_tlb_sync() on this path and the patch in question mentions this:
| To save having to reason about it too much, make sure the invalidation
| in arm_lpae_split_blk_unmap() just performs its own unconditional sync
| to minimise the window in which we're technically violating the break-
| before-make requirement on a live mapping. This might work out redundant
| with an outer-level sync for strict unmaps, but we'll never be splitting
| blocks on a DMA fastpath anyway.
However, this sync gets in the way of deferred TLB invalidation for leaf
entries and is at best a questionable, unproven hack. Remove it.
Signed-off-by: Will Deacon <will@kernel.org>