Re: [PATCH 25/28] x86: don't reserve hugetlb memory in setup_arch()

Sergey Shtylyov <[email protected]> Sun, 28 Dec 2025 16:29:49 +0300

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On 12/28/25 3:39 PM, Mike Rapoport wrote:

> From: "Mike Rapoport (Microsoft)" <[email protected]>
> 
> Commit 665eaf313314 ("x86/setup: call hugetlb_bootmem_alloc early")
> added an early call to hugetlb_bootmem_alloc() to setup_arch() to allow
> HVO style pre-initialization of vmemmap on x86.
> 
> With the ordering of hugetlb reservation vs memory map initiaization
> sorted out in core MM this no longer needs to be an architecture specific
> quirk.
> 
> Drop the call to hugetlb_bootmem_alloc() from x86::setup_arch().
> 
> Signed-off-by: Mike Rapoport (Microsoft) <[email protected]>
> ---
>  arch/x86/kernel/setup.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 1b2edd07a3e1..e2318fa9b1bb 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -1191,7 +1191,6 @@ void __init setup_arch(char **cmdline_p)
>  
>  	if (boot_cpu_has(X86_FEATURE_GBPAGES)) {
>  		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
> -		hugetlb_bootmem_alloc();
>  	}

   You need to drop {} now, no? But seeing that this *if* gets dropped
altogether in the next patch, you may as well ignore me... :-)

[...]

MBR, Sergey