Hi, On 9/2/21 9:01 PM, Martin K. Petersen wrote: > > Hans, > >> So it looks like we actually need to disable NCQ for Samsung 860/870 >> devices when the SATA controller has a vendor-id of PCI_VENDOR_ID_ATI >> rather then AMD. > > That's another great data point! > > I wonder if there actually is a Samsung problem (given that these drives > work fine on other controllers). Or if it is just the queued trim > handling that's broken on 1002:4391 controllers from ATI. > > When I originally experimented with queued trim I had systems I could > not get to work. But queued trim worked fine when the same drives were > connected to more modern chipsets (note that this was "did not work at > all" as opposed to "randomly corrupting data"). > > Do we have any evidence at all of queued trim working with non-Samsung > drives on these controllers? Not sure how many modern SATA drives > actually implement this feature. Maybe the reason we see Samsung drives > in the bug reports is due to a combination of popularity and the fact > that these drives actually implement queued trim support. The Samsung 860 / 870 series causing issues when queued trim support is enabled are quite wide-spread, covering many different controller models from all well known controller vendors (Intel, Asmedia, Marvell and AMD). So disabling queued-trim support definitely is the right thing to do (and we should have done so a long time ago, I am to blame for this not being done sooner). As for your theory that it is really a problem with the controller and not the the SSDs, I honestly do not know, but I doubt it, there are no such reports with any other vendor's SSD or newer Samsung models, so this seems unlikely. Regards, Hans