Re: [PATCH 4/5] x86/mm: Decouple kernel TLB flushes from flush_tlb_info

[Sebastian Andrzej Siewior]

On 2026-09-21 17:53:58 [+0800], Chuyi Zhou wrote:
> --- a/arch/x86/mm/tlb.c
> +++ b/arch/x86/mm/tlb.c
> @@ -1487,38 +1487,47 @@ static void invlpgb_kernel_range_flush(struct flush_tlb_info *info)
…
>  void flush_tlb_kernel_range(unsigned long start, unsigned long end)
>  {
> -	struct flush_tlb_info info;
> -
>  	guard(preempt)();
> -	init_flush_tlb_info(&info, NULL, start, end, PAGE_SHIFT, false,
> -			    TLB_GENERATION_INVALID);
>  
> -	if (info.end == TLB_FLUSH_ALL)
> +	if (end == TLB_FLUSH_ALL ||

info.end might be TLB_FLUSH_ALL because init_flush_tlb_info() might set
it so. But 'end', which is passed as an argument, should not be
TLB_FLUSH_ALL or can it?
And if so, wouldn't the check below cover it anyway?

> +	    tlb_range_exceeds_ceiling(start, end, PAGE_SHIFT))
>  		kernel_tlb_flush_all();
>  	else
> -		kernel_tlb_flush_range(&info);
> +		kernel_tlb_flush_range(start, end);
>  }

Sebastian