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>> >> - while ( i-- ) >> - /* if statement to satisfy __must_check */ >> - if ( iommu_call(hd->platform_ops, unmap_page, d, dfn_add(dfn, i), >> - flush_flags) ) >> - continue; >> + /* while statement to satisfy __must_check */ >> + while ( iommu_unmap(d, dfn, i, flush_flags) ) >> + break; > > How can this possibly be correct? > > The map_page() calls are made one 4k page at a time, and this while loop > is undoing every iteration, one 4k page at a time. > > Without this while loop, any failure after the first page will end up > not being unmapped. There's no real "while loop" here, it's effectively if ( iommu_unmap(d, dfn, i, flush_flags) ) /* nothing */; just that I wanted to avoid the empty body (but I could switch if that's preferred). Note that the 3rd argument to iommu_unmap() is i, not 1. But I have to admit that I also have trouble interpreting your last sentence - how would it matter if there was no code here at all? Or did you maybe mean "With ..." instead of "Without ..."? Jan