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Message-ID: <e9faaec1-0ddd-5691-7996-aff6f54ab160@arm.com>
Date:   Fri, 22 Apr 2022 10:11:12 +0530
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Subject: Re: [PATCH -next v5 1/5] mm: page_table_check: using PxD_SIZE instead
 of PxD_PAGE_SIZE
Content-Language: en-US
To:     Tong Tiangen <tongtiangen@huawei.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Pasha Tatashin <pasha.tatashin@soleen.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-arm-kernel@lists.infradead.org,
        linux-riscv@lists.infradead.org,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Guohanjun <guohanjun@huawei.com>
References: <20220421082042.1167967-1-tongtiangen@huawei.com>
 <20220421082042.1167967-2-tongtiangen@huawei.com>
From:   Anshuman Khandual <anshuman.khandual@arm.com>
In-Reply-To: <20220421082042.1167967-2-tongtiangen@huawei.com>
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On 4/21/22 13:50, Tong Tiangen wrote:
> Macro PUD_SIZE/PMD_SIZE is more general in various architectures. Using
> PUD_SIZE/PMD_SIZE instead of PUD_PAGE_SIZE/PMD_PAGE_SIZE can better
> support page table check in architectures other than x86 and it is no
> functional impact on x86.> 
> Suggested-by: Anshuman Khandual <anshuman.khandual@arm.com>
> Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>

There are multiple structural problems in the commit message wording
but will leave them upto Andrew, if he could fix while merging.

Otherwise LGTM

Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>

> ---
>  mm/page_table_check.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/mm/page_table_check.c b/mm/page_table_check.c
> index 2458281bff89..eb0d0b71cdf6 100644
> --- a/mm/page_table_check.c
> +++ b/mm/page_table_check.c
> @@ -177,7 +177,7 @@ void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
>  
>  	if (pmd_user_accessible_page(pmd)) {
>  		page_table_check_clear(mm, addr, pmd_pfn(pmd),
> -				       PMD_PAGE_SIZE >> PAGE_SHIFT);
> +				       PMD_SIZE >> PAGE_SHIFT);
>  	}
>  }
>  EXPORT_SYMBOL(__page_table_check_pmd_clear);
> @@ -190,7 +190,7 @@ void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
>  
>  	if (pud_user_accessible_page(pud)) {
>  		page_table_check_clear(mm, addr, pud_pfn(pud),
> -				       PUD_PAGE_SIZE >> PAGE_SHIFT);
> +				       PUD_SIZE >> PAGE_SHIFT);
>  	}
>  }
>  EXPORT_SYMBOL(__page_table_check_pud_clear);
> @@ -219,7 +219,7 @@ void __page_table_check_pmd_set(struct mm_struct *mm, unsigned long addr,
>  	__page_table_check_pmd_clear(mm, addr, *pmdp);
>  	if (pmd_user_accessible_page(pmd)) {
>  		page_table_check_set(mm, addr, pmd_pfn(pmd),
> -				     PMD_PAGE_SIZE >> PAGE_SHIFT,
> +				     PMD_SIZE >> PAGE_SHIFT,
>  				     pmd_write(pmd));
>  	}
>  }
> @@ -234,7 +234,7 @@ void __page_table_check_pud_set(struct mm_struct *mm, unsigned long addr,
>  	__page_table_check_pud_clear(mm, addr, *pudp);
>  	if (pud_user_accessible_page(pud)) {
>  		page_table_check_set(mm, addr, pud_pfn(pud),
> -				     PUD_PAGE_SIZE >> PAGE_SHIFT,
> +				     PUD_SIZE >> PAGE_SHIFT,
>  				     pud_write(pud));
>  	}
>  }