Re: BUG in kernel: Wrong Handling of USB HDD’s in scsiglue(slave_configure) and scsi/sd(sd_read_cache_type)

[James Bottomley <James.Bottomley@HansenPartnership.com>]

On Thu, 2011-09-29 at 13:27 -0500, James Bottomley wrote:
> On Thu, 2011-09-29 at 14:49 +0530, Amit Sahrawat wrote:
> > The patch did not work, although it did get pass the earlier condition
> > which I mentioned- but still Write Cache is not taken into account –
> > seems mode sensing in sd_read_cache_type() does not send proper
> > request to the device – or does not read in proper bytes for this(as
> > per hdparm command analysis):
> > 
> > Logs After Connecting:
> > scsi 0:0:0:0: Direct-Access     Seagate  Portable         0130 PQ: 0 ANSI: 4
> > sd 0:0:0:0: [sda] 488397168 512-byte logical blocks: (250 GB/232 GiB)
> > sd 0:0:0:0: [sda] Write Protect is off
> > sd 0:0:0:0: [sda] No Caching mode page present
> 
> This line means that a request for page 0x0 didn't turn up the caching
> mode page in the list of supported pages.
> 
> What does
> 
> sg_inq  --page=0x0 /dev/sda

Um, lets try that again, this time with the correct information.  What
we're looking for is the list of mode pages, so 

sg_modes --page=0x3f /dev/sda

Should return it.

Thanks,

James