linux-kernel - Re: [PATCH V2 2/6] mm/sparse: free section usage memory in case populate_section

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]

Date:   Mon, 31 May 2021 15:06:28 +0000
From:   Liam Howlett <liam.howlett@...cle.com>
To:     Dong Aisheng <aisheng.dong@....com>
CC:     "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "dongas86@...il.com" <dongas86@...il.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Mike Rapoport <rppt@...nel.org>
Subject: Re: [PATCH V2 2/6] mm/sparse: free section usage memory in case
 populate_section_memmap failed

* Dong Aisheng <aisheng.dong@....com> [210531 05:20]:
> Free section usage memory in case populate_section_memmap failed.
> We use map_count to track the remain unused memory to be freed.
> 
> Cc: Andrew Morton <akpm@...ux-foundation.org>
> Cc: Mike Rapoport <rppt@...nel.org>
> Signed-off-by: Dong Aisheng <aisheng.dong@....com>
> ---
> ChangeLog:
> v1->v2:
>  * using goto + lable according to Mike's suggestion
> ---
>  mm/sparse.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/mm/sparse.c b/mm/sparse.c
> index 7ac481353b6b..408b737e168e 100644
> --- a/mm/sparse.c
> +++ b/mm/sparse.c
> @@ -533,7 +533,7 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
>  			mem_section_usage_size() * map_count);
>  	if (!usage) {
>  		pr_err("%s: node[%d] usemap allocation failed", __func__, nid);
> -		goto failed;
> +		goto failed1;

Please use better labels for goto statements.  Perhaps usemap_failed ?


>  	}
>  	sparse_buffer_init(map_count * section_map_size(), nid);
>  	for_each_present_section_nr(pnum_begin, pnum) {
> @@ -548,17 +548,20 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
>  			pr_err("%s: node[%d] memory map backing failed. Some memory will not be available.",
>  			       __func__, nid);
>  			pnum_begin = pnum;
> -			sparse_buffer_fini();
> -			goto failed;
> +			goto failed2;

Again, this goto label is not descriptive.

>  		}
>  		check_usemap_section_nr(nid, usage);
>  		sparse_init_one_section(__nr_to_section(pnum), pnum, map, usage,
>  				SECTION_IS_EARLY);
>  		usage = (void *) usage + mem_section_usage_size();
> +		map_count--;
>  	}
>  	sparse_buffer_fini();
>  	return;
> -failed:
> +failed2:
> +	sparse_buffer_fini();
> +	memblock_free_early(__pa(usage), map_count * mem_section_usage_size());
> +failed1:
>  	/* We failed to allocate, mark all the following pnums as not present */
>  	for_each_present_section_nr(pnum_begin, pnum) {
>  		struct mem_section *ms;
> -- 
> 2.25.1
> 
>