netdev - RE: [PATCH bpf-next v2 4/8] xsk: make xskmap flush

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 for Android: free password hash cracker in your pocket

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

Message-ID: <5e14c5d4c4959_67962afd051fc5c062@john-XPS-13-9370.notmuch>
Date:   Tue, 07 Jan 2020 09:54:28 -0800
From:   John Fastabend <john.fastabend@...il.com>
To:     Björn Töpel <bjorn.topel@...il.com>,
        netdev@...r.kernel.org, ast@...nel.org, daniel@...earbox.net
Cc:     Björn Töpel <bjorn.topel@...el.com>,
        bpf@...r.kernel.org, davem@...emloft.net,
        jakub.kicinski@...ronome.com, hawk@...nel.org,
        john.fastabend@...il.com, magnus.karlsson@...el.com,
        jonathan.lemon@...il.com,
        Toke Høiland-Jørgensen <toke@...hat.com>
Subject: RE: [PATCH bpf-next v2 4/8] xsk: make xskmap flush_list common for
 all map instances

Björn Töpel wrote:
> From: Björn Töpel <bjorn.topel@...el.com>
> 
> The xskmap flush list is used to track entries that need to flushed
> from via the xdp_do_flush_map() function. This list used to be
> per-map, but there is really no reason for that. Instead make the
> flush list global for all xskmaps, which simplifies __xsk_map_flush()
> and xsk_map_alloc().
> 
> Acked-by: Toke Høiland-Jørgensen <toke@...hat.com>
> Signed-off-by: Björn Töpel <bjorn.topel@...el.com>
> ---

Just to check. The reason this is OK is because xdp_do_flush_map()
is called from NAPI context and is per CPU so the only entries on
the list will be from the current cpu napi context? Even in the case
where multiple xskmaps exist we can't have entries from more than
a single map on any list at the same time by my reading.

LGTM,
Acked-by: John Fastabend <john.fastabend@...il.com>