On 5/27/2022 10:56 AM, Naresh Kamboju wrote:

Following build failures noticed on arm64 on Linux mainline tree.

Which was detected and discussed at this email thread. https://lore.kernel.org/all/20220512193855.4f6ce32f@canb.auug.org.au/T/

Reported-by: Linux Kernel Functional Testing lkft@linaro.org

Build errors: arch/arm64/mm/hugetlbpage.c: In function 'huge_ptep_clear_flush': arch/arm64/mm/hugetlbpage.c:515:16: error: implicit declaration of function 'get_clear_flush'; did you mean 'ptep_clear_flush'? [-Werror=implicit-function-declaration] 515 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig); | ^~~~~~~~~~~~~~~ | ptep_clear_flush arch/arm64/mm/hugetlbpage.c:515:16: error: incompatible types when returning type 'int' but 'pte_t' was expected 515 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/arm64/mm/hugetlbpage.c:516:1: error: control reaches end of non-void function [-Werror=return-type] 516 | } | ^ cc1: some warnings being treated as errors

metadata: git_repo: https://gitlab.com/Linaro/lkft/mirrors/torvalds/linux-mainline git_describe: v5.18-9901-g7f50d4dfe816 git_sha: 7f50d4dfe816dd916a7cbf39039674825c2b388b git_short_log: 7f50d4dfe816 (\Merge tag 'for-linus' of https://github.com/openrisc/linux%5C) target_arch: arm64 toolchain: gcc-11

That is caused by commit:

00df1f1a133b ("mm: change huge_ptep_clear_flush() to return the original pte")

interacting with commit:

fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()")

And Catalin has fixed the conflict with below changes [1], not sure why it is not merged.

Linus, should I send a proper patch to fix this conflict for you?

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 30f5b76aabe9..9a999550df8e 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -485,12 +485,15 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, { size_t pgsize; int ncontig; + pte_t orig_pte;

if (!pte_cont(READ_ONCE(*ptep))) return ptep_clear_flush(vma, addr, ptep);

ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize); - return get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig); + orig_pte = get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig); + flush_tlb_range(vma, addr, addr + pgsize * ncontig); + return orig_pte; }

[1] https://lore.kernel.org/all/YnzqffV7STYS24Yn@arm.com/