Comment 155 for bug 445852

(In reply to comment #9)
> (In reply to comment #6)
>
> >
> > Comment #129 of the Ubuntu Bug Report is well worth reading, because it seems
> > to be isolating the bug.
>
> I don't think so. That proposed patch is bogus, identify_valid is FALSE unless
> set to TRUE anyway.
>
> Also, supposedly SMART does work with smartmontools, just not with libatasmart,
> right? That comment suggests that SMART would not work at all with those SSDs.
>
> Andrew, do you have one of the SSDs affected? Could you step through the code
> and figure out exactly which command triggers the problem?
>

I ran gdb on devkit-disks-probe-ata-smart/libatasmart. I found that it is the ioctl call from disk_smart_read_thresholds call that triggers the HSM violation in the kernel log (disk_smart_read_thresdholds calls disk_command with the argument SK_SMART_COMMAND_READ_THRESHOLDS), which calls disk_passthrough_16_command, which calls sg_io, which does an ioctl.

There is one earlier call to disk_command (with SK_ATA_COMMAND_IDENTIFY_DEVICE), but that does not the trigger the HSM violation in the kernel log. So I believe it is the way that the SSD reacts to the READ_THRESHOLDS command that throws off the kernel.

Raf.