On Wed, Apr 6, 2016 at 9:37 AM, William Tu <[email protected]> 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 <[email protected]> > --- > 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 } > } > > static void > -- > 2.5.0 > > _______________________________________________ > dev mailing list > [email protected] > http://openvswitch.org/mailman/listinfo/dev > _______________________________________________ dev mailing list [email protected] http://openvswitch.org/mailman/listinfo/dev
