netdev - Re: [PATCH][next][v2] iavf: use kvzalloc instead of kzalloc for rx/tx

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] [day] [month] [year] [list]

Date:   Mon, 14 Sep 2020 16:24:18 -0700
From:   Jesse Brandeburg <jesse.brandeburg@...el.com>
To:     Li RongQing <lirongqing@...du.com>
Cc:     <netdev@...r.kernel.org>, <intel-wired-lan@...ts.osuosl.org>,
        <edumazet@...gle.com>
Subject: Re: [PATCH][next][v2] iavf: use kvzalloc instead of kzalloc for
 rx/tx_bi buffer

Li RongQing wrote:

> when changes the rx/tx ring to 4096, kzalloc may fail due to
> a temporary shortage on slab entries.
> 
> so using kvmalloc to allocate this memory as there is no need
> that this memory area is physical continuously.
> 
> and using __GFP_RETRY_MAYFAIL to allocate from kmalloc as
> far as possible, which can reduce TLB pressure than vmalloc
> as suggested by Eric Dumazet

This change is no good, it's using RETRY_MAYFAIL but still using
v*alloc.

Please see my replies to the i40e version of the patch. I don't think
we should apply these.