Re: Storage device enumeration script

["Torbjørn Skagestad" <torbjorn@itpas.no>]

Hi,

I'm hitting this as well.It seems to be triggered by my non-existing
floppy device.

As there is no real floppy device connected, no driver is loaded, so we
never see a /driver directory. This loop then goes all the way up to /,
where it loops forever at 100% cpu.


from probe_controller()
151 while cpath and not os.path.exists(cpath+'/driver'):
152		cpath = os.path.dirname(cpath)
153		if cpath in controllers:
154			return controllers[cpath]


On Thu, 2011-05-26 at 14:22 -0400, Phil Turmel wrote:
> On 05/26/2011 02:12 PM, Roman Mamedov wrote:
> [...]
> > Now it locks up with 100% CPU load and no output, I waited for a couple of
> > minutes. On Ctrl-C:
> > 
> > ^CTraceback (most recent call last):
> >   File "./lsdrv", line 274, in <module>
> >     probe_block('/sys/block/'+x)
> > 
> > $ ls /sys/block/
> > etherd!e1.5  etherd!e2.1  md0  md2  sda  sdc  sde  sdg
> > etherd!e1.6  fd0          md1  md4  sdb  sdd  sdf
> > 
> > The first two devices are actually down at this moment, maybe that's the
> > reason? Still I'd expect not 100% CPU load by lsdrv, but 0% CPU and 100%
> > iowait in this case.
> 
> Sounds like an infinite loop, or infinite recursion.  Could you apply the temporary patch below so I can see how far the probing got?
> 
> > Output of the old (bash) lsdrv:
> > 
> > Controller device @ pci0000:00/0000:00:06.0 [pata_amd]
> >   IDE interface: nVidia Corporation CK804 IDE (rev f2)
> >     host8: [Empty]
> >     host9: [Empty]
> > Controller device @ pci0000:00/0000:00:07.0 [sata_nv]
> >   IDE interface: nVidia Corporation CK804 Serial ATA Controller (rev f3)
> >     host6: /dev/sdd ATA Hitachi HDS5C302 {SN: ..............}
> >     host7: /dev/sde ATA WDC WD15EADS-00S {SN: ..............}
> > Controller device @ pci0000:00/0000:00:08.0 [sata_nv]
> >   IDE interface: nVidia Corporation CK804 Serial ATA Controller (rev f3)
> >     host10: /dev/sdf ATA WDC WD20EADS-00S {SN: ..............}
> >     host11: /dev/sdg ATA WDC WD20EADS-00S {SN: ..............}
> > Controller device @ pci0000:00/0000:00:0d.0/0000:02:00.0 [ahci]
> >   SATA controller: Marvell Technology Group Ltd. 88SE9123 PCIe SATA 6.0 Gb/s
> > controller (rev 10) host4: /dev/sdc ATA Hitachi HDS5C302 {SN: ..............}
> >     host5: [Empty]
> > Controller device @ pci0000:00/0000:00:0e.0/0000:01:00.0 [sata_mv]
> >   SCSI storage controller: Marvell Technology Group Ltd. 88SX7042 PCI-e 4-port
> > SATA-II (rev 02) host0: [Empty]
> >     host1: [Empty]
> >     host2: /dev/sda ATA ST31000528AS {SN: ..............}
> >     host3: /dev/sdb ATA Hitachi HDS72202 {SN: ..............}
> 
> The old code never attempted to recurse into the layers of block devices, so it can't have recursion problems.
> 
> Phil
> 
> 8<-------------------------
> 
> diff --git a/lsdrv b/lsdrv
> index d1caaf8..37728c1 100755
> --- a/lsdrv
> +++ b/lsdrv
> @@ -145,6 +145,7 @@ def sect2size(sectors):
>  # the struct object w/ filled in details.
>  controllers=dict()
>  def probe_controller(cpathlink):
> +	print "Probing controller %s" % cpathlink
>  	cpath = os.path.realpath(cpathlink)
>  	if cpath in controllers:
>  		return controllers[cpath]
> @@ -186,6 +187,7 @@ def probe_controller(cpathlink):
>  # controller.
>  phydevs=dict()
>  def probe_device(devpathlink, nodestr):
> +	print "Probing device %s" % devpathlink
>  	devpath = os.path.realpath(devpathlink)
>  	if devpath in phydevs:
>  		return phydevs[devpath]
> @@ -214,6 +216,7 @@ def probe_device(devpathlink, nodestr):
>  blockbyname=dict()
>  blockbynode=dict()
>  def probe_block(blocklink):
> +	print "Probing block %s" % blocklink
>  	name=blocklink.rsplit('/', 1)[-1]
>  	if name in blockbyname:
>  		return

-- 
Torbjørn Skagestad
Ide Til Produkt A/S

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