On Fri, Jul 11, 2025 at 07:17:29AM -0700, Jakub Kicinski wrote: > On Fri, 11 Jul 2025 02:14:03 +0000 Hangbin Liu wrote: > > > sleep 5 > > > + # Schedule out for a bit, address GC runs from the power efficient WQ > > > + # if the long sleep above has put the whole system into sleep state > > > + # the WQ may have not had a chance to run. > > > + sleep 0.1 > > > + > > > > How about use slowwait to check if the address still exists. > > Weirdly if we read the addresses twice they disappear, I haven't looked > into the code for the why, but seemed like using slowwait could > potentially mask the addresses sticking around when nobody runs > the Netlink handlers for a while? Dunno..
Not sure if I understand correctly. Do you mean the addresses will keep there if we use slowwait? Thanks Hangbin > > I queued this debug patch a couple of months ago: > > sleep 5 > - run_cmd_grep_fail "10.23.11." ip addr show dev "$devdummy" > + ip addr show dev "$devdummy" > /tmp/a > + run_cmd_grep_fail "10.23.11." cat /tmp/a > if [ $? -eq 0 ]; then > - check_err 1 > - end_test "FAIL: preferred_lft addresses remaining" > + check_err 1 > + cat /tmp/a > + echo "===" > + ip addr show dev "$devdummy" > + end_test "FAIL: preferred_lft addresses remaining ($lft)" > return > fi > > And when it flakes the output looks like this: > > # 7.23 [+7.00] 297: test-dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc > noqueue state UNKNOWN group default qlen 1000 > # 7.23 [+0.00] link/ether 9e:a6:c4:c2:1b:16 brd ff:ff:ff:ff:ff:ff > # 7.23 [+0.00] inet 10.23.11.81/32 scope global deprecated dynamic > test-dummy0 > # 7.23 [+0.00] valid_lft 0sec preferred_lft 0sec > # 7.23 [+0.00] inet 10.23.11.84/32 scope global deprecated dynamic > test-dummy0 > # 7.24 [+0.00] valid_lft 0sec preferred_lft 0sec > # 7.24 [+0.00] inet 10.23.11.93/32 scope global deprecated dynamic > test-dummy0 > # 7.24 [+0.00] valid_lft 0sec preferred_lft 0sec > # 7.24 [+0.00] inet 10.23.11.94/32 scope global deprecated dynamic > test-dummy0 > # 7.24 [+0.00] valid_lft 0sec preferred_lft 0sec > # 7.24 [+0.00] inet 10.23.11.97/32 scope global deprecated dynamic > test-dummy0 > # 7.24 [+0.00] valid_lft 0sec preferred_lft 0sec > # 7.24 [+0.00] inet 10.23.11.99/32 scope global deprecated dynamic > test-dummy0 > # 7.24 [+0.00] valid_lft 0sec preferred_lft 0sec > # 7.24 [+0.00] inet6 fe80::9ca6:c4ff:fec2:1b16/64 scope link proto > kernel_ll > # 7.24 [+0.00] valid_lft forever preferred_lft forever > # 7.24 [+0.00] === > # 7.25 [+0.00] 297: test-dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc > noqueue state UNKNOWN group default qlen 1000 > # 7.25 [+0.00] link/ether 9e:a6:c4:c2:1b:16 brd ff:ff:ff:ff:ff:ff > # 7.25 [+0.00] inet6 fe80::9ca6:c4ff:fec2:1b16/64 scope link proto > kernel_ll > # 7.25 [+0.00] valid_lft forever preferred_lft forever > # 7.25 [+0.00] FAIL: preferred_lft addresses remaining (1)
