On Fri, 27 Jun 2014 08:48:01 -0700 James Bottomley <[email protected]> wrote:
> On Fri, 2014-06-27 at 17:34 +0200, Michael Büsch wrote:
> > I tried the following patch:
> >
> > Index: linux/drivers/scsi/sd.c
> > ===================================================================
> > --- linux.orig/drivers/scsi/sd.c 2014-06-26 18:40:39.214696552 +0200
> > +++ linux/drivers/scsi/sd.c 2014-06-27 15:52:30.776159456 +0200
> > @@ -2440,7 +2440,7 @@ sd_read_cache_type(struct scsi_disk *sdk
> > sdkp->RCD = 0;
> > }
> >
> > - sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
> > + sdkp->DPOFUA = 0;
> > if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
> > sd_first_printk(KERN_NOTICE, sdkp,
> > "Uses READ/WRITE(6), disabling FUA\n");
> >
> >
> > This obviously is not the correct thing to do, but it makes the disk usable:
> >
> > Jun 27 17:26:50 marge kernel: [ 523.909815] usb 2-1: new SuperSpeed USB
> > device number 2 using xhci_hcd
> > Jun 27 17:26:50 marge kernel: [ 523.929246] usb 2-1: New USB device found,
> > idVendor=152d, idProduct=0567
> > Jun 27 17:26:50 marge kernel: [ 523.929258] usb 2-1: New USB device
> > strings: Mfr=1, Product=2, SerialNumber=3
> > Jun 27 17:26:50 marge kernel: [ 523.929265] usb 2-1: Product: USB to
> > ATA/ATAPI Bridge
> > Jun 27 17:26:50 marge kernel: [ 523.929271] usb 2-1: Manufacturer: JMicron
> > Jun 27 17:26:50 marge kernel: [ 523.929276] usb 2-1: SerialNumber: xxx
> > Jun 27 17:26:50 marge kernel: [ 523.930999] usb-storage 2-1:1.0: USB Mass
> > Storage device detected
> > Jun 27 17:26:50 marge kernel: [ 523.931237] scsi12 : usb-storage 2-1:1.0
> > Jun 27 17:26:51 marge kernel: [ 524.930451] scsi 12:0:0:0: Direct-Access
> > JMicron Generic 0114 PQ: 0 ANSI: 6
> > Jun 27 17:26:51 marge kernel: [ 524.931228] sd 12:0:0:0: Attached scsi
> > generic sg3 type 0
> > Jun 27 17:26:51 marge kernel: [ 524.932964] sd 12:0:0:0: [sdd] Spinning up
> > disk...
> > Jun 27 17:26:53 marge kernel: [ 525.937848] ..ready
> > Jun 27 17:26:53 marge kernel: [ 526.942395] sd 12:0:0:0: [sdd] 976773168
> > 512-byte logical blocks: (500 GB/465 GiB)
> > Jun 27 17:26:53 marge kernel: [ 526.943037] sd 12:0:0:0: [sdd] Write
> > Protect is off
> > Jun 27 17:26:53 marge kernel: [ 526.943048] sd 12:0:0:0: [sdd] Mode Sense:
> > 47 00 10 08
> > Jun 27 17:26:53 marge kernel: [ 526.943662] sd 12:0:0:0: [sdd] Write
> > cache: enabled, read cache: enabled, doesn't support DPO or FUA
> > Jun 27 17:26:53 marge kernel: [ 526.987919] sdd: sdd1
> > Jun 27 17:26:53 marge kernel: [ 526.990055] sd 12:0:0:0: [sdd] Attached
> > SCSI disk
> > Jun 27 17:27:29 marge kernel: [ 563.227849] EXT4-fs (sdd1): warning:
> > mounting fs with errors, running e2fsck is recommended
> > Jun 27 17:27:29 marge kernel: [ 563.228043] EXT4-fs (sdd1): mounted
> > filesystem with ordered data mode. Opts: (null)
> >
> > (This is on another machine, but it shows the same behavior without the
> > patch.)
> >
> > Does somebody have a hint for a real fix?
>
> I suspect the problem is in the USB bridge: The device reports FUA
> support in its initial IDENTIFY, which gets translated to the correct
> mode page bits, but when we send a READ/WRITE with the FUA bit set, the
> bridge doesn't know how to translate it and gives us the error. There's
> probably some way in USB to blacklist the bridge, but we need to
> understand the consequences of the blacklist: The device is claiming a
> writeback cache which means if it won't do either FUA or SYNC CACHE,
> there's going to be a data integrity failure.
>
> The fact that your initial hack works suggests that sync cache is
> accepted by it, so we probably just need a USB blacklist fixing the FUA
> problem.
[Added USB lists to Cc]
--
Michael
signature.asc
Description: PGP signature

