linux-kernel - Re: [PATCH 4/9] mm/madvise: remove len parameter of madvise_do

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5dce5c3b-b20b-49b0-9e28-7909ff81500d@lucifer.local>
Date: Tue, 11 Mar 2025 12:05:39 +0000
From: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
To: SeongJae Park <sj@...nel.org>
Cc: Andrew Morton <akpm@...ux-foundation.org>,
        "Liam R. Howlett" <howlett@...il.com>,
        David Hildenbrand <david@...hat.com>,
        Shakeel Butt <shakeel.butt@...ux.dev>,
        Vlastimil Babka <vbabka@...e.cz>, kernel-team@...a.com,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [PATCH 4/9] mm/madvise: remove len parameter of
 madvise_do_behavior()

On Mon, Mar 10, 2025 at 10:23:13AM -0700, SeongJae Park wrote:
> Because madise_should_skip() logic is factored out, making
> madvise_do_behavior() calculates 'len' on its own rather then receiving
> it as a parameter makes code simpler.  Remove the parameter.
>
> Signed-off-by: SeongJae Park <sj@...nel.org>

LGTM, so:

Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>

> ---
>  mm/madvise.c | 10 ++++------
>  1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/mm/madvise.c b/mm/madvise.c
> index 764ec1f2475b..469c25690a0e 100644
> --- a/mm/madvise.c
> +++ b/mm/madvise.c
> @@ -1673,7 +1673,7 @@ static bool is_madvise_populate(int behavior)
>  }
>
>  static int madvise_do_behavior(struct mm_struct *mm,
> -		unsigned long start, size_t len_in, size_t len, int behavior)
> +		unsigned long start, size_t len_in, int behavior)
>  {
>  	struct blk_plug plug;
>  	unsigned long end;
> @@ -1682,7 +1682,7 @@ static int madvise_do_behavior(struct mm_struct *mm,
>  	if (is_memory_failure(behavior))
>  		return madvise_inject_error(behavior, start, start + len_in);
>  	start = untagged_addr_remote(mm, start);
> -	end = start + len;
> +	end = start + PAGE_ALIGN(len_in);
>
>  	blk_start_plug(&plug);
>  	if (is_madvise_populate(behavior))
> @@ -1775,8 +1775,7 @@ int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int beh
>  	error = madvise_lock(mm, behavior);
>  	if (error)
>  		return error;
> -	error = madvise_do_behavior(mm, start, len_in, PAGE_ALIGN(len_in),
> -			behavior);
> +	error = madvise_do_behavior(mm, start, len_in, behavior);
>  	madvise_unlock(mm, behavior);
>
>  	return error;
> @@ -1808,8 +1807,7 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
>  		if (madvise_should_skip(start, len_in, behavior, &error))
>  			ret = error;
>  		else
> -			ret = madvise_do_behavior(mm, start, len_in,
> -					PAGE_ALIGN(len_in), behavior);
> +			ret = madvise_do_behavior(mm, start, len_in, behavior);
>  		/*
>  		 * An madvise operation is attempting to restart the syscall,
>  		 * but we cannot proceed as it would not be correct to repeat
> --
> 2.39.5