On Sun, 7 Jul 2019, Aldo Mazzeo wrote:
> I'm running OpenBSD 6.5 on my apu2d4 and I have an external USB3 hard 
> drive attached (it is powered by a separate cable). The external hd is 
> FFS-formatted with softdep enabled and the kernel panics once every 
> 24-36h with the following DDB details:

As you've found, softdep is dangerous when a drive may be unexpected 
disconnected as it has critical sections where it cannot tolerate the 
inability to do I/O and will panic.

In this case, it appears the I/O error was caused by the drive being 
disconnected at the USB level:
...
> disk_gone(ffffffff8156adc0,1) at disk_gone+0x68
> sddetach(ffff800000139600,1) at sddetach+0x3a
> config_detach(ffff800000139600,1) at config_detach+0x154
> scsi_detach_lun(ffff800000133900,1,0,1) at scsi_detach_lun+0xc8
> scsi_detach_bus(ffff800000133900,1) at scsi_detach_bus+0xcf
> scsibusdetach(ffff800000133900,1) at scsibusdetach+0x2e
> config_detach(ffff800000133900,1) at config_detach+0x154
> umass_scsi_detach(ffff800000139200,1) at umass_scsi_detach+0x35
> umass_detach(ffff800000139200,1) at umass_detach+0xd4
> config_detach(ffff800000139200,1) at config_detach+0x154
> usbd_detach(ffff80000013a000,ffff800000080500) at usbd_detach+0x5a
> uhub_port_connect(ffff800000080500,3,2a0,202) at uhub_port_connect+0x68



> When I connected my usb-to-serial adapter in order to get some details
> about the crash, I was getting no output. I started getting it
> immediately after I disconnected the hard drive.

I don't really understand the timeline of events here, but disconnecting a 
harddrive with a mounted filesystem using softdeps will break things.  
Don't Do That.


> Do you have any idea of the cause of this issue? Maybe a faulty hard 
> drive? I was using this same hard drive with Linux and I don't remember 
> having issues. I am going to disable softdep to see if things get 
> better.

That should help with the panics.  Watch your dmesg for additional reports 
of I/O errors that might indicate failures of the drive itself.


Philip Guenther

Reply via email to