Subject: Re: [PATCH net-next] ipv4: do not abuse GFP_ATOMIC in inet_netconf_notify_devconf()

From: Nicolas Dichtel <[email-masked]>
Date: Fri, 8 Jul 2016 09:54:08 +0200

Le 08/07/2016 05:18, Eric Dumazet a écrit :
> From: Eric Dumazet <[email-masked]>
> 
> inet_forward_change() runs with RTNL held.
> We are allowed to sleep if required.
> 
> If we use __in_dev_get_rtnl() instead of __in_dev_get_rcu(),
> we no longer have to use GFP_ATOMIC allocations in
> inet_netconf_notify_devconf(), meaning we are less likely to miss
> notifications under memory pressure, and wont touch precious memory
> reserves either and risk dropping incoming packets.
> 
> inet_netconf_get_devconf() can also use GFP_KERNEL allocation.
> 
> Fixes: edc9e748934c ("rtnl/ipv4: use netconf msg to advertise forwarding status")
> Fixes: 9e5511106f99 ("rtnl/ipv4: add support of RTM_GETNETCONF")
> Signed-off-by: Eric Dumazet <[email-masked]>
> Cc: Nicolas Dichtel <[email-masked]>
Acked-by: Nicolas Dichtel <[email-masked]>

Nice catch, thank you!