Messages in this thread | | | Date | Mon, 3 Oct 2011 15:53:45 -0400 (EDT) | From | Alan Stern <> | Subject | Re: Re: BUG in kernel: Wrong Handling of USB HDD’s in scsiglue(slave_configure) and scsi/sd(sd_read_cache_type) |
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On Mon, 3 Oct 2011, James Bottomley wrote:
> On Mon, 2011-10-03 at 14:10 -0400, Alan Stern wrote: > > > No. You need to also take into account the RBC > > > device parameters mode page if present. See above. > > > > All right, suppose neither page is present. Does it then make sense to > > assume by default that write caching is enabled? > > You're the USB expert ... if we do that, we'll start sending > SYNCHRONIZE_CACHE commands down to a whole slew of devices we didn't > before ... is that going to cause problems with any USB SATLs?
Hmmm... Actually, I doubt it would bother any SATLs, but it might well bother other sorts of USB translation layers. No way to tell without trying it, and I don't really want to deal with the fallout.
Maybe a better question to be asking is this: What happens when one of these drives (the ones that report their caching capabilities incorrectly) is plugged into a Windows system?
Alan Stern
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