On Thu, 23 Apr 2009 04:54:03 pm David Miller wrote: > From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > Date: Thu, 23 Apr 2009 16:38:47 +1000 > > > Today's linux-next build (powerpc allyesconfig gcc4.4.0) produced these > > warnings: > > > > drivers/net/virtio_net.c: In function 'virnet_vlan_rx_add_vid': > > include/linux/scatterlist.h:57: warning: 'sg' is used uninitialized in this function > > drivers/net/virtio_net.c:746: note: 'sg' was declared here > > drivers/net/virtio_net.c: In function 'virnet_vlan_rx_kill_vid': > > include/linux/scatterlist.h:57: warning: 'sg' is used uninitialized in this function > > drivers/net/virtio_net.c:758: note: 'sg' was declared here > > > > in each case, sg is uninitialised when its address is passed to > > sg_set_buf() which passes it to gs_set_page() which passes it to > > sg_assign_page() which dereferences it (to use ->page_link). > > I wonder if this is a side effect of changes that went in via Rusty's > tree? I don't remember touching this driver in a while. AFAICT gcc is right: it should be sg_init_one(). It doesn't currently *matter*, since no virtio add_buf implementation does that chained-sg crap (I had a patch once, but it made me barf) and so the uninitialized lower three bits are ignored. Alex, if you agree, patch welcome... Rusty. -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
