Re: Question for Patch"libsas: fix "sysfs group not found" warnings at port teardown time"
On 05/02/2016 21:33, Praveen Murali wrote: 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). Praveen I can't find the original full discussion on this. My impression is that the fix is incorrect as the port should not be deleted in sas_destruct_devices(). I also tried this patch and got a NULL deference when I unplugged the disk from the expander. We get the warn as the port is deleted before the device which is attached to it. The tricky part is that the port and devices are deleted in seperate work structs being processed in same work queue (shost wq). The first cannot be relinquished to allow the second to run. One (undesirable) solution is to call sas_destruct_devices() directly from sas_unregister_dev(). On Feb 5, 2016, at 1:20 AM, wangyijing 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: GW 4.1.6+ #140 [] dump_backtrace+0x0/0x124 [] show_stack+0x10/0x1c [] warn_slowpath_fmt+0x4c/0x58 [] device_add+0x28c/0x5b8 [] sas_port_add+0x20/0xbc [] sas_porte_bytes_dmaed [] 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 -- 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
Re: Question for Patch"libsas: fix "sysfs group not found" warnings at port teardown time"
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 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: GW 4.1.6+ #140 >> [] dump_backtrace+0x0/0x124 >> [] show_stack+0x10/0x1c >> [] warn_slowpath_fmt+0x4c/0x58 >> [] device_add+0x28c/0x5b8 >> [] sas_port_add+0x20/0xbc >> [] sas_porte_bytes_dmaed >> [] 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
Re: Question for Patch"libsas: fix "sysfs group not found" warnings at port teardown time"
Yes, it seems to be the same issue. 在 2016/2/6 1:22, Dāvis Mosāns 写道: > 2016-02-05 11:20 GMT+02:00 wangyijing : >> >> 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 >> > > Maybe this is related? > > kernel: WARNING: CPU: 4 PID: 16820 at fs/sysfs/group.c:237 > sysfs_remove_group+0x8b/0x90() > kernel: sysfs group 818a3b60 not found for kobject 'end_device-7:7' > [...] > kernel: Workqueue: scsi_wq_7 sas_destruct_devices [libsas] > > I'm getting this warning when removing disk from HighPoint RocketRAID 2760 > controller (mvsas driver) > See https://bugzilla.kernel.org/show_bug.cgi?id=71021#c3 > -- > 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
Re: Question for Patch"libsas: fix "sysfs group not found" warnings at port teardown time"
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). Praveen > On Feb 5, 2016, at 1:20 AM, wangyijing 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: GW 4.1.6+ #140 > [] dump_backtrace+0x0/0x124 > [] show_stack+0x10/0x1c > [] warn_slowpath_fmt+0x4c/0x58 > [] device_add+0x28c/0x5b8 > [] sas_port_add+0x20/0xbc > [] sas_porte_bytes_dmaed > [] 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
Re: Question for Patch"libsas: fix "sysfs group not found" warnings at port teardown time"
2016-02-05 11:20 GMT+02:00 wangyijing : > > 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 > Maybe this is related? kernel: WARNING: CPU: 4 PID: 16820 at fs/sysfs/group.c:237 sysfs_remove_group+0x8b/0x90() kernel: sysfs group 818a3b60 not found for kobject 'end_device-7:7' [...] kernel: Workqueue: scsi_wq_7 sas_destruct_devices [libsas] I'm getting this warning when removing disk from HighPoint RocketRAID 2760 controller (mvsas driver) See https://bugzilla.kernel.org/show_bug.cgi?id=71021#c3 -- 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
Question for Patch"libsas: fix "sysfs group not found" warnings at port teardown time"
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: GW 4.1.6+ #140 [] dump_backtrace+0x0/0x124 [] show_stack+0x10/0x1c [] warn_slowpath_fmt+0x4c/0x58 [] device_add+0x28c/0x5b8 [] sas_port_add+0x20/0xbc [] sas_porte_bytes_dmaed [] 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