在 2016/2/6 5:33, Praveen Murali 写道: > Hi Yijing, > The fix was deemed inappropriate and I think the explanation provided by > James was kind similar to what your observation is. Also, as far as I > remember the consensus was that these error messages (sysfs group not found) > are harmless at this point. I think James can provide a better explanation > and direction for you (copying him here).
Hi Praveen, thanks for your reply. This call trace seems to be harmless, but it's a bad impression to users. I didn't find the James comment on this patch, do you have the link ? Thanks! Yijing. > > Praveen > >> On Feb 5, 2016, at 1:20 AM, wangyijing <wangyij...@huawei.com> wrote: >> >> Hi Dan and Praveen, >> I found a patch titled "libsas: fix "sysfs group not found" warnings at >> port teardown time" by google, >> https://www.mail-archive.com/linux-scsi@vger.kernel.org/msg39187.html >> >> I found the same warning calltrace in my platform, but I didn't find the >> patch changes in the latest kernel 4.5-rc2. >> So is this issue still in kernel ? >> >> I think your patch could fix this issue we found, but I'm worried about >> another problem. >> >> Now when unplug a disk >> >> LLDD report a event loss_of_singal >> sas_deform_port >> sas_unregister_domain_devices >> sas_unregister_dev >> sas_discover_event(dev->port, DISCE_DESTRUCT); >> sas_port_delete >> phy->port = NULL; >> >> and after your patch changes >> >> LLDD report a event loss_of_singal >> sas_deform_port >> sas_unregister_domain_devices >> sas_unregister_dev >> sas_discover_event(dev->port, DISCE_DESTRUCT); >> phy->port = NULL; >> >> ... >> sas_destruct_devices >> sas_port_delete //now we actually delete the port device, but >> we set phy->port = NULL; before this time. >> >> >> So if we hotplug the disk quickly, plug,unplug,plug, >> The new dmaed event(plug) would try to alloc and add a new port, but the old >> port device is still alive. >> Another calltrace would occur >> >> WARNING: CPU: 0 PID: 1038 at lib/kobject.c:240 >> kobject_add_internal+0x258/0x318() >> kobject_add_internal failed for port-0:0 with -EEXIST, don't try to register >> things with the same name in the same directory. >> CPU: 0 PID: 1038 Comm: kworker/u64:2 Tainted: G W 4.1.6+ #140 >> [<ffff800000089918>] dump_backtrace+0x0/0x124 >> [<ffff800000089a4c>] show_stack+0x10/0x1c >> [<ffff80000009fcbc>] warn_slowpath_fmt+0x4c/0x58 >> [<ffff8000003cdc04>] device_add+0x28c/0x5b8 >> [<ffff80000040d4ec>] sas_port_add+0x20/0xbc >> [<ffff80000040f3e8>] sas_porte_bytes_dmaed >> [<ffff8000000b5504>] process_one_work+0x13c/0x344 >> >> Because I am not a sas guy, so if you could comment this or post new patch, >> I would be thanks a lot! >> >> Thanks! >> Yijing. >> >> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in >> the body of a message to majord...@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
