> Can you please share the Linux Distribution information along with sparc > machine specification.
Sun Fire V210 (dual UltraSPARC IIIi), onboard NICs with tg3 driver. Debian unstable snapshot (as last seen in Debian): deb http://snapshot.debian.org/archive/debian/20150725T121538Z/ unstable main contrib non-free except for udev and libudev1 that are 218-8 (older) because the latest udev at that moment was broken. This implies gcc version 4.9.3 (Debian 4.9.3-2). > Regards, > Deepak Khungar > > On Wed, Oct 19, 2016 at 10:18 AM, Siva Reddy Kallam > <siva.kal...@broadcom.com> wrote: > On Mon, Oct 17, 2016 at 6:35 PM, Meelis Roos <mr...@linux.ee> wrote: > >> > Now I reproduced the bug even with 4.7-rc1 so it is older than > 4.7. Will > >> > test further. > >> > >> It gets stranger and stranger - my old 4.7 image worked fine, freshly > >> compiled 4.7 exhibits the same problem. > >> > >> Toolchain has not changed, that I know for sure. > >> > >> What may have changed is kernel .config. My old conf was with > whatever I > >> had during 4.7. Then I upgraded to 4.8-rc3 and then 4.8 and selected > >> values for "make oldconfig" new entries. Then went back to 4.7-rc1 > and > >> then to 4.7 with this config, answering quiestion about new options > when > >> any appeared. Diff is not available since I do not have the old > configs > >> archived. > > > > I did some more digging. Found an older configuration that is working > > and recreated a newer one that is bad, for the same 4.7 kernel. This > is > > reproducible now, from "make clean" state. > > > > Working config from 4.7-rc4 attached as config-4.7, broken config from > > 4.7 attached as config-4.7-bad. > > > > Will try to bisect the configs as time permits. But looking at the > > stack traces, the issue is probably timing related, when ip and > dhclient > > do something with the same lock. seq_read that outputs stats could be > > reading /proc/net/dev that reads counters from each interface. > > > > ifupdown seems to use the following for dhcp interfaces: > > up > > [[/bin/ip link set dev %iface% address %hwaddress%]] > > /sbin/dhclient -v -pf /run/dhclient.%iface%.pid -lf > /var/lib/dhcp/dhclient.%iface%.leases -I -df > /var/lib/dhcp/dhclient6.%iface%.leases %iface% \ > > ... > > > > so ip link is setting link up, this creates some work for the > > background, and the dhclient goes adn reads /proc/net/dev, and lockup > is > > suspected but not proven? > > > > I started a loop for test, doing cat /proc/net/dev in a loop and at > the > > same link link up and down from console, but up and down is slow > process > > and the loop did not seem to trigger the warning over night, so it was > > not so simple. > > > I am busy with other priority tasks. One of my colleague Deepak will > work this with you. > I added him to CC list. > Thanks. > > > >> > > [ 83.716570] BUG: spinlock lockup suspected on CPU#0, > dhclient/1014 > >> > > [ 83.797819] lock: 0xfff000123c8e4a08, .magic: dead4ead, > .owner: ip/1001, .owner_cpu: 1 > >> > > [ 83.903130] CPU: 0 PID: 1014 Comm: dhclient Not tainted 4.8.0 > #4 > >> > > [ 83.982129] Call Trace: > >> > > [ 84.014160] [00000000004b7220] spin_dump+0x60/0xa0 > >> > > [ 84.078203] [00000000004b73a0] do_raw_spin_lock+0xa0/0x120 > >> > > [ 84.106344] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready > >> > > [ 84.107193] ip (1001) used greatest stack depth: 2168 bytes > left > >> > > [ 84.306955] [000000000092c0d0] _raw_spin_lock_bh+0x30/0x40 > >> > > [ 84.380188] [00000000100822cc] tg3_get_stats64+0xc/0x80 [tg3] > >> > > [ 84.456885] [00000000007fac8c] dev_get_stats+0x2c/0xc0 > >> > > [ 84.525506] [000000000081a4e8] dev_seq_printf_stats+0x8/0xe0 > >> > > [ 84.600986] [000000000081a5e4] dev_seq_show+0x24/0x40 > >> > > [ 84.668467] [00000000005cb6c4] seq_read+0x2c4/0x440 > >> > > [ 84.733656] [000000000060b97c] proc_reg_read+0x3c/0x80 > >> > > [ 84.802282] [00000000005a219c] __vfs_read+0x1c/0x140 > >> > > [ 84.868613] [00000000005a2310] vfs_read+0x50/0x100 > >> > > [ 84.932662] [00000000005a265c] SyS_read+0x3c/0xa0 > >> > > [ 84.995573] [00000000004061d4] > linux_sparc_syscall32+0x34/0x60 > >> > > [ 85.073748] * CPU[ 0]: TSTATE[00000044f0001a22] > TPC[00000000f79a16b0] TNPC[00000000f79a16b4] TASK[dhclient:1014] > >> > > [ 85.208732] TPC[f79a16b0] O7[f79405c8] I7[0] > RPC[0] > >> > > [ 85.287633] CPU[ 1]: TSTATE[0000004480001605] > TPC[00000000004b26f0] TNPC[00000000004d0b0c] TASK[swapper/1:0] > >> > > [ 85.420338] TPC[trace_hardirqs_off+0x10/0x20] > O7[rcu_idle_enter+0x64/0xa0] I7[cpu_startup_entry+0x1b0/0x240] > RPC[rest_init+0x178/0x1a0] > >> > > [ 85.664600] tg3 0000:00:02.0 eth0: Link is up at 100 Mbps, > full duplex > >> > > [ 85.750515] tg3 0000:00:02.0 eth0: Flow control is off for TX > and off for RX > >> > > [ 85.843994] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes > ready > > > > -- > > Meelis Roos (mr...@linux.ee) > > > > -- Meelis Roos (mr...@ut.ee) http://www.cs.ut.ee/~mroos/
