On Wed, Oct 7, 2015 at 7:38 AM, Neil Horman <nhor...@redhat.com> wrote: > On Tue, Oct 06, 2015 at 10:12:56PM -0700, Vinson Lee wrote: >> On Fri, Oct 2, 2015 at 6:10 AM, Neil Horman <nhor...@redhat.com> wrote: >> > On Thu, Oct 01, 2015 at 08:25:46PM -0700, Vinson Lee wrote: >> >> Hi. >> >> >> >> I am seeing a netpoll_send_skb_on_dev warning with bnx2. It happens on >> >> Linux 4.1 and I am able to reproduce the warning with Linux 4.3-rc3. >> >> >> >> ------------[ cut here ]------------ >> >> WARNING: CPU: 11 PID: 3110 at net/core/netpoll.c:368 >> >> netpoll_send_skb_on_dev+0x183/0x201() >> >> netpoll_send_skb_on_dev(): eth0 enabled interrupts in poll >> >> (bnx2_start_xmit+0x0/0x5d4 [bnx2]) >> >> Modules linked in: netconsole(+) configfs ipv6 ppdev parport_pc lp >> >> parport tcp_diag inet_diag ipmi_devintf serio_raw iTCO_wdt >> >> iTCO_vendor_support ipmi_si ipmi_msghandler hpilo hpwdt bnx2 coretemp >> >> kvm_intel kvm crc32c_intel ghash_clmulni_intel microcode lpc_ich >> >> mfd_core i7core_edac edac_core pcc_cpufreq acpi_cpufreq shpchp >> >> sch_fq_codel hpsa radeon ttm drm_kms_helper drm fb_sys_fops sysimgblt >> >> sysfillrect syscopyarea i2c_algo_bit i2c_core >> >> CPU: 11 PID: 3110 Comm: modprobe Not tainted 4.3.0-rc3 #1 >> >> 0000000000000170 ffff88060be17a18 ffffffff812bc84c ffffffff818b1a78 >> >> ffff88060be17a68 ffff88060be17a58 ffffffff81064712 000000000be17a68 >> >> ffffffff814ec12e ffff88060bc10900 0000000000000000 ffff8800d941c000 >> >> Call Trace: >> >> [<ffffffff812bc84c>] dump_stack+0x48/0x5c >> >> [<ffffffff81064712>] warn_slowpath_common+0xa1/0xbb >> >> [<ffffffff814ec12e>] ? netpoll_send_skb_on_dev+0x183/0x201 >> >> [<ffffffff810647cf>] warn_slowpath_fmt+0x46/0x48 >> >> [<ffffffffa039a6b9>] ? bnx2_run_loopback+0x391/0x391 [bnx2] >> >> [<ffffffff814ec12e>] netpoll_send_skb_on_dev+0x183/0x201 >> >> [<ffffffff814ec58b>] netpoll_send_udp+0x3df/0x3f1 >> >> [<ffffffffa049324a>] write_msg+0xaf/0xe9 [netconsole] >> >> [<ffffffff810a6daa>] call_console_drivers.clone.2+0xd1/0xe9 >> >> [<ffffffff810a70d0>] console_unlock+0x30e/0x3a5 >> >> [<ffffffff810a757d>] register_console+0x2af/0x322 >> >> [<ffffffffa04971b4>] init_netconsole+0x1b4/0x224 [netconsole] >> >> [<ffffffffa0497000>] ? 0xffffffffa0497000 >> >> [<ffffffff810002bf>] do_one_initcall+0xf7/0x182 >> >> [<ffffffff811764fe>] ? kmem_cache_alloc_trace+0xb6/0xf0 >> >> [<ffffffff810cb8d8>] ? do_init_module+0x31/0x1e4 >> >> [<ffffffff810cb910>] do_init_module+0x69/0x1e4 >> >> [<ffffffff810ccedc>] load_module+0x1451/0x160b >> >> [<ffffffff810ca1a3>] ? mod_kobject_put+0x4d/0x4d >> >> [<ffffffff811606f3>] ? __vmalloc_node+0x3e/0x40 >> >> [<ffffffff810cd2aa>] SyS_init_module+0x14f/0x155 >> >> [<ffffffff815833d7>] entry_SYSCALL_64_fastpath+0x12/0x6a >> >> ---[ end trace 878215466e581776 ]--- >> >> >> >> Cheers, >> >> Vinson >> > >> > Hmm, that would suggest that someone called local_irq_enable in either the >> > xmit, >> > poll_controller or napi poll paths (or one of its always-disable, >> > bretheren), >> > but I dont see where that might be happening. Are you able to instrument >> > the >> > kernel (either by cloning that WARN_ON_ONCE call or via stap script), so >> > we can >> > further isolate which call path the problem is happening in? >> > >> > Neil >> > >> >> I bisected the regression and it is introduced with this Linux 3.19-rc1 >> commit. >> >> e22b886a8a43b147e1994a9f970f678fc0df2033 is the first bad commit >> commit e22b886a8a43b147e1994a9f970f678fc0df2033 >> Author: Peter Zijlstra <pet...@infradead.org> >> Date: Wed Sep 24 10:18:48 2014 +0200 >> >> sched/wait: Add might_sleep() checks >> >> Add more might_sleep() checks, suppose someone put a wait_event() like >> thing in a wait loop.. >> >> Can't put might_sleep() in ___wait_event() because there's the locked >> primitives which call ___wait_event() with locks held. >> >> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> >> Cc: t...@linutronix.de >> Cc: ilya.dryo...@inktank.com >> Cc: umgwanakikb...@gmail.com >> Cc: Oleg Nesterov <o...@redhat.com> >> Cc: Linus Torvalds <torva...@linux-foundation.org> >> Link: http://lkml.kernel.org/r/20140924082242.119255...@infradead.org >> Signed-off-by: Ingo Molnar <mi...@kernel.org> >> >> :040000 040000 1536c4cc3c706b4129452ce023c69733b46a23e4 >> 22c894c6ae02be75e5f772d39fde178f036e906f M include >> >> Vinson > > That doesn't make any sense. That commitis just adding some warning messages, > it doesn't change any locking or irq enablement states. That in turn suggests > that you are seeing something is transient and sensitive to timing. What > driver > is eth0 using? Is it bnx2 or something else? > > Neil >
eth0 is using bnx2. $ ethtool -i eth0 driver: bnx2 version: 2.2.6 firmware-version: bc 5.2.3 NCSI 2.0.12 bus-info: 0000:03:00.0 supports-statistics: yes supports-test: yes supports-eeprom-access: yes supports-register-dump: yes supports-priv-flags: no I can add some WARN_ON_ONCE calls elsewhere in the kernel. Do you have suggestions where or can provide me an example patch? Vinson -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
