Re: [PATCH 0/1] Summary: hwmon driver for temperature sensors on SATA drives

[Guenter Roeck]

On Tue, Dec 17, 2019 at 05:50:17AM +0000, Damien Le Moal wrote:
> On 2019/12/17 12:57, Guenter Roeck wrote:
> > On 12/16/19 6:35 PM, Martin K. Petersen wrote:
> >>
> >> Guenter,
> >>
> >>> If and when drives are detected which report bad information, such
> >>> drives can be added to a blacklist without impact on the core SCSI or
> >>> ATA code. Until that happens, not loading the driver solves the
> >>> problem on any affected system.
> >>
> >> My only concern with that is that we'll have blacklisting several
> >> places. We already have ATA and SCSI blacklists. If we now add a third
> >> place, that's going to be a maintenance nightmare.
> >>
> >> More on that below.
> >>
> >>>> My concerns are wrt. identifying whether SMART data is available for
> >>>> USB/UAS. I am not too worried about ATA and "real" SCSI (ignoring RAID
> >>>> controllers that hide the real drives in various ways).
> >>
> >> OK, so I spent my weekend tinkering with 15+ years of accumulated USB
> >> devices. And my conclusion is that no, we can't in any sensible manner,
> >> support USB storage monitoring in the kernel. There is no heuristic that
> >> I can find that identifies that "this is a hard drive or an SSD and
> >> attempting one of the various SMART methods may be safe". As opposed to
> >> "this is a USB key that's likely to lock up if you try". And that's
> >> ignoring the drives with USB-ATA bridges that I managed to wedge in my
> >> attempt at sending down commands.
> >>
> >> Even smartmontools is failing to work on a huge part of my vintage
> >> collection.  Thanks to a wide variety of bridges with random, custom
> >> interfaces.
> >>
> >> So my stance on all this is that I'm fine with your general approach for
> >> ATA. I will post a patch adding the required bits for SCSI. And if a
> >> device does not implement either of the two standard methods, people
> >> should use smartmontools.
> >>
> >> Wrt. name, since I've added SCSI support, satatemp is a bit of a
> >> misnomer. drivetemp, maybe? No particular preference.
> >>
> > Agreed, if we extend this to SCSI, satatemp is less than perfect.
> > drivetemp ? disktemp ? I am open to suggestions, with maybe a small
> > personal preference for disktemp out of those two.
> 
> "disk" tend to imply HDD, excluding SSDs. So my vote goes to
> "drivetemp", or even the more generic, "devtemp".
> 
"devtemp" would apply to all devices with temperature sensors, which
would be a bit too generic. I'll take that as a vote for "drivetemp".

Guenter