Hello again On Sunday 31 October 2010 01:16:02 Simon Horman wrote: > On Sat, Oct 30, 2010 at 05:55:32PM +0300, Julian Anastasov wrote: [ snip ] > > > > - What is the right thing to do in ip_vs_conn_fill_param_sync > > when ip_vs_pe_get() does not find PE? May be to drop > > connection? May be in ip_vs_process_message() we should > > use one pointer for end of message (it was 'p' before now), > > so that we can skip connections, for example, when some > > mandatory parameter as PE is not supported. We should not > > drop the whole sync message. When message is invalid it > > should be dropped but lack of support should not hurt > > other connections. In the case for PE may be > > ip_vs_conn_fill_param_sync() should return 1 if > > PE is unknown (ip_vs_pe_get). Then caller will continue > > with next connection if result > 0 or will drop message > > if result < 0 as in current patch. May be the pe_name > > presence should be the first check in > > ip_vs_conn_fill_param_sync. > > Yes, I agree with this. > > > Also note that p->pe is > > pointer without reference while called in ip_vs_sched_persist. > > In our case with ip_vs_conn_fill_param_sync we should > > put this reference after calling ip_vs_proc_conn(). > > May be ip_vs_find_dest should check that p->pe matches > > svc->pe. ip_vs_try_bind_dest should provide p->pe too > > for this check. But we must somehow ignore new conns > > with PE if they don't have cp->dest (service) because > > it is risky to attach PE that is not held by svc. > > It is bad that the check for p->pe is before > > ip_vs_find_dest. > > I have a patch, "IPVS: Add persistence engine to connection entry" > that attaches the pe to the connection rather than the dest. > In this case, if pe is NULL, then the connection doesn't use > pe, which is fine. If its non-NULL, its there so there is no > problem in that case either. > > I think this resolves the issue that you raise. There is a little Ooops with this, a locking problem. We are in a local_bh_disable() when trying to load a module... in the sync_thread() ... local_bh_disable(); ip_vs_process_message(tinfo->buf, len); local_bh_enable(); When ip_vs_process_message() get pe_data it calls -> ip_vs_conn_fill_param_sync() and it calls --> ip_vs_pe_getbyname() and it might call ----> request_module(..) My suggestion is to avoid modul loading by calling "__ip_vs_pe_getbyname()" instead, and if it fails just drop that single sync_conn. Any other ideas ? -- Regards Hans Schillstrom <hans.schillstrom@xxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe lvs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
