On Wed, Sep 18, 2024 at 6:51 PM Nikolay Aleksandrov <razor@xxxxxxxxxxxxx> wrote: > > On 18/09/2024 11:35, Jiwon Kim wrote: > > Add net_ratelimit to reduce warnings and logs. > > This addresses the WARNING in bond_xdp_get_xmit_slave reported by syzbot. > > > > This commit message is severely lacking. I did the heavy lifting and gave you > detailed analysis of the problem, please describe the actual issue and why > this is ok to do. Also the subject is confusing, it should give a concise > summary of what the patch is trying to do and please don't include filenames in it. > You can take a look at other commits for examples. > > > Setup: > > # Need xdp_tx_prog with return XDP_TX; > > ip l add veth0 type veth peer veth1 > > ip l add veth3 type veth peer veth4 > > ip l add bond0 type bond mode 6 # <- BOND_MODE_ALB, unsupported by xdp > > ip l add bond1 type bond # <- BOND_MODE_ROUNDROBIN by default > > ip l set veth0 master bond1 > > ip l set bond1 up > > ip l set dev bond1 xdpdrv object tx_xdp.o section xdp_tx > > ip l set veth3 master bond0 > > ip l set bond0 up > > ip l set veth4 up > > ip l set veth3 xdpgeneric object tx_xdp.o section xdp_tx > > Care to explain why this setup would trigger anything? > > > > > Reported-by: syzbot+c187823a52ed505b2257@xxxxxxxxxxxxxxxxxxxxxxxxx > > Closes: https://syzkaller.appspot.com/bug?extid=c187823a52ed505b2257 > > Fixes: 9e2ee5c7e7c3 ("net, bonding: Add XDP support to the bonding driver") > > Signed-off-by: Jiwon Kim <jiwonaid0@xxxxxxxxx> > > --- > > v2: Change the patch to fix bond_xdp_get_xmit_slave > > --- > > drivers/net/bonding/bond_main.c | 9 ++++++--- > > 1 file changed, 6 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c > > index b560644ee1b1..91b9cbdcf274 100644 > > --- a/drivers/net/bonding/bond_main.c > > +++ b/drivers/net/bonding/bond_main.c > > @@ -5610,9 +5610,12 @@ bond_xdp_get_xmit_slave(struct net_device *bond_dev, struct xdp_buff *xdp) > > break; > > > > default: > > - /* Should never happen. Mode guarded by bond_xdp_check() */ > > - netdev_err(bond_dev, "Unknown bonding mode %d for xdp xmit\n", BOND_MODE(bond)); > > - WARN_ON_ONCE(1); > > + /* This might occur when a bond device increases bpf_master_redirect_enabled_key, > > + * and another bond device with XDP_TX and bond slave. > > + */ > > The comment is confusing and needs to be reworded or dropped altogether. > > > + if (net_ratelimit()) > > + netdev_err(bond_dev, "Unknown bonding mode %d for xdp xmit\n", > > + BOND_MODE(bond)); > > return NULL; > > } > > > Hi Nikolay, I have taken the time to review your feedback and have sent [PATCH net v3] for your consideration. Please take a look when you have a moment. Thank you so much! Sincerely, Jiwon Kim
