Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

On Thu, 25 Aug 2016 12:05:33 +0300 Shmulik Ladkani wrote: > The BUG occurs when GRO occurs on the ingress, and only if GRO merges > skbs into the frag_list (OTOH when segments are only placed into frags[] > of a single skb, skb_segment succeeds even if gso_size was

Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

On Thu, Aug 25, 2016 at 12:05:33PM +0300, Shmulik Ladkani wrote: > > We have few alternatives for gso_size clamping: > > 1 Fix 'skb_segment' arithmentics to support inputs that do not match > the "frag_list members terminate on exact MSS" assumption. > > 2 Perform gso_size clamping in

Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

Hi, On Mon, 22 Aug 2016 14:58:42 +0200, f...@strlen.de wrote: > Shmulik Ladkani wrote: > > There are cases where gso skbs (which originate from an ingress > > interface) have a gso_size value that exceeds the output dst mtu: > > > > - ipv4 forwarding middlebox having

Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

Shmulik Ladkani wrote: > > Normal ipv4 routing via vm1, no iptables etc. present, so > > > > we have hypervisor 1500 -> 1500 VM1 1280 -> 1280 VM2 > > > > Turning off gro avoids this problem. > > I hit the BUG only when VM2's mtu is not set to 1280 (kept to the 1500

Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

Hi, On Mon, 22 Aug 2016 14:58:42 +0200, f...@strlen.de wrote: > > Florian, in fe6cc55f you described a BUG due to gso_size decrease. > > I've tested both bridged and routed cases, but in my setups failed to > > hit the issue; Appreciate if you can provide some hints. > > Still get the BUG, I

Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

Shmulik Ladkani wrote: > There are cases where gso skbs (which originate from an ingress > interface) have a gso_size value that exceeds the output dst mtu: > > - ipv4 forwarding middlebox having in/out interfaces with different mtus >addressed by fe6cc55f3a 'net:

Re: [RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

Hi, On Mon, 22 Aug 2016 14:58:42 +0200, f...@strlen.de wrote: > > > > Florian, in fe6cc55f you described a BUG due to gso_size decrease. > > I've tested both bridged and routed cases, but in my setups failed to > > hit the issue; Appreciate if you can provide some hints. > > Still get the

[RFC PATCH] net: ip_finish_output_gso: Attempt gso_size clamping if segments exceed mtu

There are cases where gso skbs (which originate from an ingress interface) have a gso_size value that exceeds the output dst mtu: - ipv4 forwarding middlebox having in/out interfaces with different mtus addressed by fe6cc55f3a 'net: ip, ipv6: handle gso skbs in forwarding path' - bridge