Re: linux-next: build failure after merge of the mm tree

From: Matthew Wilcox
Date: Mon Aug 21 2023 - 21:12:16 EST


On Tue, Aug 22, 2023 at 09:55:37AM +1000, Stephen Rothwell wrote:
> In file included from include/trace/trace_events.h:27,
> from include/trace/define_trace.h:102,
> from fs/xfs/xfs_trace.h:4428,
> from fs/xfs/xfs_trace.c:45:
> include/linux/pgtable.h:8:25: error: initializer element is not constant
> 8 | #define PMD_ORDER (PMD_SHIFT - PAGE_SHIFT)

Ummm. PowerPC doesn't have a compile-time constant PMD size?

arch/powerpc/include/asm/book3s/64/pgtable.h:#define PMD_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
arch/powerpc/include/asm/book3s/64/pgtable.h:#define PTE_INDEX_SIZE __pte_index_size

That's really annoying. I'll try to work around it.