Re: [PATCH 0/2] sparc64: D-cache alias flushing fixes

[John Paul Adrian Glaubitz]

Hi Imre,

On Sun, 2026-09-27 at 12:55 +0200, Imre Kaloz wrote:
> Two fixes to D-cache alias flushing on sparc64 CPUs with a virtually
> indexed L1 D-cache.
> 
> Patch 1 makes move_pte() and tlb_batch_add() flush only the page a PTE
> maps, instead of every page of its folio once per PTE, so the number
> of cross-calls for an mremap() of a large folio no longer grows with
> the square of its size.
> 
> Patch 2 implements flush_cache_vmap() and flush_cache_vunmap(), which
> have been no-ops on sparc64.  Stale lines left by a vmalloc mapping
> corrupt BPF programs and module data on UltraSPARC III.  It uses
> flush_dcache_page_all() as patch 1 restores it.
> 
> Both patches are tagged for stable.  Tested on a Sun Ultra 45.
> 
> Imre Kaloz (2):
>   sparc64: flush only the aliased page, not its whole folio
>   sparc64: flush vmalloc ranges from the D-cache on map and unmap
> 
>  arch/sparc/include/asm/cacheflush_64.h |  9 ++--
>  arch/sparc/include/asm/pgtable_64.h    |  7 ++-
>  arch/sparc/kernel/smp_64.c             | 42 ++++++++++++-----
>  arch/sparc/mm/init_64.c                | 64 ++++++++++++++++++++++++++
>  arch/sparc/mm/tlb.c                    |  2 +-
>  arch/sparc/mm/ultra.S                  | 25 ++++++++++
>  6 files changed, 131 insertions(+), 18 deletions(-)
> 
> 
> base-commit: fe2ec83746e501645709761605c2464a44fd2929

Would you mind reporting the bugs that these patches fix in the sparclinux
issue tracker on GitHub [1]? The reason I'm asking is that there has been
recently a strong uptick of patches for SPARC and I want to make sure we're
not missing any when Andreas gets back to reviewing patches.

Adrian

> [1] https://github.com/sparclinux/issues/issues

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