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Subject: Re: [PATCH] x86/mm: Fix flush_tlb_range() when used for zapping
 normal PMDs
From: Rik van Riel <riel@surriel.com>
To: Jann Horn <jannh@google.com>, Dave Hansen <dave.hansen@linux.intel.com>,
  Andy Lutomirski	 <luto@kernel.org>, Peter Zijlstra <peterz@infradead.org>
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Date: Fri, 03 Jan 2025 16:55:25 -0500
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On Fri, 2025-01-03 at 19:39 +0100, Jann Horn wrote:
> 02fc2aa06e9e0ecdba3fe948cafe5892b72e86c0..3da645139748538daac70166618d
> 8ad95116eb74 100644
> --- a/arch/x86/include/asm/tlbflush.h
> +++ b/arch/x86/include/asm/tlbflush.h
> @@ -242,7 +242,7 @@ void flush_tlb_multi(const struct cpumask
> *cpumask,
> =C2=A0	flush_tlb_mm_range((vma)->vm_mm, start,
> end,			\
> =C2=A0			=C2=A0=C2=A0 ((vma)->vm_flags &
> VM_HUGETLB)		\
> =C2=A0				?
> huge_page_shift(hstate_vma(vma))	\
> -				: PAGE_SHIFT, false)
> +				: PAGE_SHIFT, true)
> =C2=A0
>=20

The code looks good, but should this macro get
a comment indicating that code that only frees
pages, but not page tables, should be calling
flush_tlb() instead?

--=20
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