Hi Darrell and Daniele, Thanks for the comments! I will use dp_packet_rss_invalidate() instead and send v2 patch.
Regards, William On Wed, Apr 6, 2016 at 11:26 AM, Daniele Di Proietto <diproiet...@ovn.org> wrote: > 2016-04-06 10:09 GMT-07:00 Darrell Ball <dlu...@gmail.com>: > > On Wed, Apr 6, 2016 at 9:37 AM, William Tu <u9012...@gmail.com> wrote: > > > >> Valgrind reports "Conditional jump or move depends on uninitialised > value" > >> and "Use of uninitialised value" at case 2016 ovn -- 3 HVs, 1 LS, 3 > >> lports/HV. It is caused by reading uninitialized 'key->hash' at > >> emc_lookup() > >> and 'rss_hash_valid' from dp_packet_rss_valid(). At emc_processing(), > >> the value of key->hash is initilized by > dpif_netdev_packet_get_rss_hash(), > >> which returns an uninitialized hash value. Call stacks below: > >> > >> - Connditional jump or move depends on uninitialised value(s) > >> dpif_netdev_packet_get_rss_hash (dpif-netdev.c:3334) > >> emc_processing (dpif-netdev.c:3455) > >> dp_netdev_input__ (dpif-netdev.c:3639) > >> and, > >> - Use of uninitialised value of size 8 > >> emc_lookup (dpif-netdev.c:1785) > >> emc_processing (dpif-netdev.c:3457) > >> dp_netdev_input__ (dpif-netdev.c:3639) > >> > >> Signed-off-by: William Tu <u9012...@gmail.com> > >> --- > >> lib/dp-packet.c | 9 ++++++++- > >> 1 file changed, 8 insertions(+), 1 deletion(-) > >> > >> diff --git a/lib/dp-packet.c b/lib/dp-packet.c > >> index aec7fe7..87ed329 100644 > >> --- a/lib/dp-packet.c > >> +++ b/lib/dp-packet.c > >> @@ -1,5 +1,5 @@ > >> /* > >> - * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc. > >> + * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2016 Nicira, Inc. > >> * > >> * Licensed under the Apache License, Version 2.0 (the "License"); > >> * you may not use this file except in compliance with the License. > >> @@ -29,6 +29,13 @@ dp_packet_init__(struct dp_packet *b, size_t > allocated, > >> enum dp_packet_source so > >> b->source = source; > >> dp_packet_reset_offsets(b); > >> pkt_metadata_init(&b->md, 0); > >> +#ifdef DPDK_NETDEV > >> + b->mbuf.ol_flags &= ~PKT_RX_RSS_HASH; > >> + b->mbuf.hash.rss = 0; > >> +#else > >> + b->rss_hash_valid = false; > >> + b->rss_hash = 0; > >> +#endif > >> > > > > > > Just a general comment, not a review: > > > > Do you need to set the hash value to zero as well as set > > the "hash_valid" flag to false; should not setting the "hash_valid" > > flag to false be enough to handle a <potential> initialization issue ? > > > > I think there is already an API for setting "hash_valid" > > to false here > > > > static inline void > > dp_packet_rss_invalidate(struct dp_packet *p) > > { > > #ifdef DPDK_NETDEV > > p->mbuf.ol_flags &= ~PKT_RX_RSS_HASH; > > #else > > p->rss_hash_valid = false; > > #endif > > } > > > > > > I agree with Darrell, I think it's better to use > dp_packet_rss_invalidate(). > > Also, if we include dp_packet_rss_invalidate() in dp_packet_init__(), > we will have redundant calls to dp_packet_rss_invalidate() in > netdev-{bsd,dummy,linux}.c. Would you mind removing those? There's > another one in netdev-dpdk.c, but that will be requires anyway. > > Would you mind sending a v2 with the suggested changes? > > Thanks! > _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev