Subject: Re: linux-next: Tree for Apr 6 (arch/x86/mm/init_64.c)

From: Oscar Salvador <[email-masked]>
Date: Tue, 6 Apr 2021 21:57:03 +0200

On Tue, Apr 06, 2021 at 11:39:47AM -0700, Randy Dunlap wrote:
 
> > Looks like that compound "if" is too much for gcc 7.5.0 to handle:
> > 
> > 			} else if (IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP) &&
> > 				   vmemmap_pmd_is_unused(addr, next)) {
> > 					free_hugepage_table(pmd_page(*pmd),
> > 							    altmap);
> > 					spin_lock(&init_mm.page_table_lock);
> > 					pmd_clear(pmd);
> > 					spin_unlock(&init_mm.page_table_lock);
> > 			}
> > 
> > 
> 
> This is what I am using for now:

Hi Randy

Yeah, that is what v4 was using [1].
We decided to get rid of the ifdef for costimetic reasons but it seems
it does not do the trick.

I will ask Andrew to squash that on top.

[1] https://patchwork.kernel.org/project/linux-mm/patch/[email-masked]/

Thanks

> 
> ---
> ---
>  arch/x86/mm/init_64.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> --- linux-next-20210406.orig/arch/x86/mm/init_64.c
> +++ linux-next-20210406/arch/x86/mm/init_64.c
> @@ -1123,14 +1123,16 @@ remove_pmd_table(pmd_t *pmd_start, unsig
>  				pmd_clear(pmd);
>  				spin_unlock(&init_mm.page_table_lock);
>  				pages++;
> -			} else if (IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP) &&
> -				   vmemmap_pmd_is_unused(addr, next)) {
> +			}
> +#ifdef CONFIG_SPARSEMEM_VMEMMAP
> +			else if (vmemmap_pmd_is_unused(addr, next)) {
>  					free_hugepage_table(pmd_page(*pmd),
>  							    altmap);
>  					spin_lock(&init_mm.page_table_lock);
>  					pmd_clear(pmd);
>  					spin_unlock(&init_mm.page_table_lock);
>  			}
> +#endif
>  
>  			continue;
>  		}
> 

-- 
Oscar Salvador
SUSE L3