[RESPONDED] AMD 13 7840 Issues with 2TB SSD portable disk behind a Thunderbolt dock

Hello.
I have FW 13, AMD 7840U version, and I use Arch Linux there, kernel 6.6.8-arch1-1. I use Samsung Portable SSD T7 Shield, the 2TB variant. Connects via USB-C with max transfer speed of 10Gbps. I also have a Dell WD22TB4, a Thunderbolt 4 docking station.

When connecting the SSD through that dock, a data transfer freeze occurs consistently after transferring approx. 48.5 GB of data of a specific file. I have further narrowed it down that approx after transferring 271 GB from the beginning of the drive, I start getting timeouts.
It does not matter which USB port on the dock I use, the result is identical.
When connecting the SSD directly via the USB4 on the laptop, the transfer does not freeze, and also if I connect the dock via the USB3.2 port on the Framework laptop, then the transfer will also not freeze.

FREEZES:
FW laptop USB4 port <–> Dell WD22TB4 dock <–> PSSD T7 Shield 2TB

OK:
FW laptop USB3.2 port <–> Dell WD22TB4 dock <–> PSSD T7 Shield 2TB
FW laptop, any USB port <–> PSSD T7 Shield 2TB

I had Kensington SD5700T docking station previously, also Thunderbolt 4, and it exhibited the same issue, so I returned it and bought this Dell. Now I think the issue is somewhere else.
I have updated both the Dell dock firmware, and the SSD drive firmware, but the issues persist.

This is the point where the transfer freezes:

sudo dd if=/dev/sda1 of=/dev/null bs=16M status=progress
270599716864 bytes (271 GB, 252 GiB) copied, 351 s, 771 MB/s
# ... freeze, I pulled the cable out
16176+1 records in
16176+1 records out
271403155456 bytes (271 GB, 253 GiB) copied, 395.775 s, 686 MB/s

# kernel log during the freeze period:
Jan 04 17:17:41 paulos-fw kernel: sd 0:0:0:0: [sda] tag#29 uas_eh_abort_handler 0 uas-tag 12 inflight: CMD IN 
Jan 04 17:17:41 paulos-fw kernel: sd 0:0:0:0: [sda] tag#29 CDB: Read(10) 28 00 1f 98 e6 98 00 04 00 00
Jan 04 17:17:41 paulos-fw kernel: sd 0:0:0:0: [sda] tag#28 uas_eh_abort_handler 0 uas-tag 11 inflight: CMD IN 
Jan 04 17:17:41 paulos-fw kernel: sd 0:0:0:0: [sda] tag#28 CDB: Read(10) 28 00 1f 98 e2 98 00 04 00 00
Jan 04 17:17:41 paulos-fw kernel: sd 0:0:0:0: [sda] tag#27 uas_eh_abort_handler 0 uas-tag 21 inflight: CMD IN 
Jan 04 17:17:41 paulos-fw kernel: sd 0:0:0:0: [sda] tag#27 CDB: Read(10) 28 00 1f 98 a5 c0 00 04 00 00
# ... a lot longer

I then decided to narrow down the problem, however I have limited time to spend with this problem right now.

sudo dd if=/dev/sda1 of=read-err bs=512 skip=530092000 count=200 status=progress
# freezes right away, this output is after disconnecting the uSB
200+0 records in
200+0 records out
102400 bytes (102 kB, 100 KiB) copied, 133.953 s, 0.8 kB/s

# the whole kernel log:
Jan 04 17:29:51 paulos-fw kernel: usb 8-1.4.2: new SuperSpeed Plus Gen 2x1 USB device number 35 using xhci_hcd
Jan 04 17:29:51 paulos-fw kernel: usb 8-1.4.2: New USB device found, idVendor=04e8, idProduct=61fb, bcdDevice= 1.00
Jan 04 17:29:51 paulos-fw kernel: usb 8-1.4.2: New USB device strings: Mfr=2, Product=3, SerialNumber=1
Jan 04 17:29:51 paulos-fw kernel: usb 8-1.4.2: Product: PSSD T7 Shield
Jan 04 17:29:51 paulos-fw kernel: usb 8-1.4.2: Manufacturer: Samsung
Jan 04 17:29:51 paulos-fw kernel: usb 8-1.4.2: SerialNumber: xxxxxxxxxxxxxx
Jan 04 17:29:51 paulos-fw kernel: scsi host0: uas
Jan 04 17:29:51 paulos-fw kernel: scsi 0:0:0:0: Direct-Access     Samsung  PSSD T7 Shield   0    PQ: 0 ANSI: 6
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] 3907029168 512-byte logical blocks: (2.00 TB/1.82 TiB)
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] Write Protect is off
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] Preferred minimum I/O size 512 bytes
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] Optimal transfer size 33553920 bytes
Jan 04 17:29:51 paulos-fw kernel:  sda: sda1
Jan 04 17:29:51 paulos-fw kernel: sd 0:0:0:0: [sda] Attached SCSI disk
...
# dozens of seconds during the freeze
...
Jan 04 17:32:49 paulos-fw kernel: sd 0:0:0:0: [sda] tag#4 uas_eh_abort_handler 0 uas-tag 2 inflight: CMD IN 
Jan 04 17:32:49 paulos-fw kernel: sd 0:0:0:0: [sda] tag#4 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 04 17:32:49 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler start
Jan 04 17:32:49 paulos-fw kernel: usb 8-1.4.2: reset SuperSpeed Plus Gen 2x1 USB device number 35 using xhci_hcd
Jan 04 17:32:49 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler success
Jan 04 17:33:20 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler start
Jan 04 17:33:20 paulos-fw kernel: sd 0:0:0:0: [sda] tag#0 uas_zap_pending 0 uas-tag 1 inflight: CMD 
Jan 04 17:33:20 paulos-fw kernel: sd 0:0:0:0: [sda] tag#0 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 04 17:33:20 paulos-fw kernel: usb 8-1.4.2: reset SuperSpeed Plus Gen 2x1 USB device number 35 using xhci_hcd
Jan 04 17:33:20 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler success
Jan 04 17:33:51 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler start
Jan 04 17:33:51 paulos-fw kernel: sd 0:0:0:0: [sda] tag#1 uas_zap_pending 0 uas-tag 1 inflight: CMD 
Jan 04 17:33:51 paulos-fw kernel: sd 0:0:0:0: [sda] tag#1 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 04 17:33:51 paulos-fw kernel: usb 8-1.4.2: reset SuperSpeed Plus Gen 2x1 USB device number 35 using xhci_hcd
Jan 04 17:33:51 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler success
Jan 04 17:34:21 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler start
Jan 04 17:34:21 paulos-fw kernel: sd 0:0:0:0: [sda] tag#2 uas_zap_pending 0 uas-tag 1 inflight: CMD 
Jan 04 17:34:21 paulos-fw kernel: sd 0:0:0:0: [sda] tag#2 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 04 17:34:21 paulos-fw kernel: usb 8-1.4.2: reset SuperSpeed Plus Gen 2x1 USB device number 35 using xhci_hcd
Jan 04 17:34:21 paulos-fw kernel: scsi host0: uas_eh_device_reset_handler success
Jan 04 17:34:22 paulos-fw kernel: sd 0:0:0:0: [sda] tag#3 data cmplt err -71 uas-tag 1 inflight: CMD 
Jan 04 17:34:22 paulos-fw kernel: sd 0:0:0:0: [sda] tag#3 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
...
# here I decided to pull the USB from the SSD drive
...
Jan 04 17:34:31 paulos-fw kernel: usb 8-1.4.2: USB disconnect, device number 35
Jan 04 17:34:31 paulos-fw kernel: sd 0:0:0:0: [sda] tag#3 uas_zap_pending 0 uas-tag 1 inflight: CMD 
Jan 04 17:34:31 paulos-fw kernel: sd 0:0:0:0: [sda] tag#3 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 04 17:34:31 paulos-fw kernel: sd 0:0:0:0: [sda] tag#3 FAILED Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK cmd_age=133s
Jan 04 17:34:31 paulos-fw kernel: sd 0:0:0:0: [sda] tag#3 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 04 17:34:31 paulos-fw kernel: I/O error, dev sda, sector 530095752 op 0x0:(READ) flags 0x80700 phys_seg 128 prio class 2
Jan 04 17:34:31 paulos-fw kernel: sd 0:0:0:0: [sda] Synchronizing SCSI cache
Jan 04 17:34:32 paulos-fw kernel: sd 0:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK

This is how the dock looks in boltctl:

 ● Dell WD22TB4 Thunderbolt Dock
   β”œβ”€ type:          peripheral
   β”œβ”€ name:          WD22TB4 Thunderbolt Dock
   β”œβ”€ vendor:        Dell
   β”œβ”€ uuid:          5b4e8780-0070-194c-ffff-ffffffffffff
   β”œβ”€ generation:    USB4
   β”œβ”€ status:        authorized
   β”‚  β”œβ”€ domain:     e92c3804-1143-96c4-ffff-ffffffffffff
   β”‚  β”œβ”€ rx speed:   40 Gb/s = 2 lanes * 20 Gb/s
   β”‚  β”œβ”€ tx speed:   40 Gb/s = 2 lanes * 20 Gb/s
   β”‚  └─ authflags:  none
   β”œβ”€ authorized:    Thu 04 Jan 2024 02:37:29 PM UTC
   β”œβ”€ connected:     Thu 04 Jan 2024 02:37:28 PM UTC
   └─ stored:        Thu 04 Jan 2024 01:36:25 PM UTC
      β”œβ”€ policy:     iommu
      └─ key:        no

I can make a support topic out of this if needed, I just thought to post it here if someone has any ideas… I will be grateful for any advice. I do not have a different Thunderbolt laptop to try this on right now…

Thanks,
Pavel

Hi Pavel,

Appreciate the thoroughness of this post.

We always recommend using expansion cards to device as that is within our wheelhouse of control, however, it sounds like in your case this dock behavior is pretty repeatable.

Question: Can you test this with an Ubuntu 22.04.3 ISO on USB? I’d like to match this up with another configuration. I suspect the same result, but would like to compare just to make sure.

After the comparison, this is feedback I will provide to the engineering team.

Appreciate you bring this to your attention.

Hi @Matt_Hartley,
thanks for taking attention.

Yes, I just tested Ubuntu 22.04.3 ISO on USB and it reproduces there too. (Had to modify the sector count, but otherwise it was reproducible just the same.)

ubuntu@ubuntu:/media/ubuntu/T7 Shield$ sudo dd if=/dev/sdc1 of=/tmp/read-err bs=512 skip=530092000 count=10000 status=progress
^C^Cdd: error reading '/dev/sdc1': Input/output error
680+0 records in
680+0 records out
348160 bytes (348 kB, 340 KiB) copied, 57.2625 s, 6.1 kB/s

kernel log

Jan 05 19:34:12 ubuntu kernel: Linux version 6.2.0-26-generic (buildd@bos03-amd64-042) (x86_64-linux-gnu-gcc-11 (Ubuntu 11.3.0-1ubuntu1~22.04.1) 11.3.0, GNU ld (GNU Binutils for Ubuntu) 2.38) #26~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Jul 13 16:27:29 UTC 2 (Ubuntu 6.2.0-26.26~22.04.1-generic 6.2.13)
Jan 05 19:34:12 ubuntu kernel: Command line: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed maybe-ubiquity quiet splash ---
...
Jan 05 19:41:47 ubuntu kernel: usb 8-1.4.2: new SuperSpeed Plus Gen 2x1 USB device number 7 using xhci_hcd
Jan 05 19:41:47 ubuntu kernel: usb 8-1.4.2: New USB device found, idVendor=04e8, idProduct=61fb, bcdDevice= 1.00
Jan 05 19:41:47 ubuntu kernel: usb 8-1.4.2: New USB device strings: Mfr=2, Product=3, SerialNumber=1
Jan 05 19:41:47 ubuntu kernel: usb 8-1.4.2: Product: PSSD T7 Shield
Jan 05 19:41:47 ubuntu kernel: usb 8-1.4.2: Manufacturer: Samsung
Jan 05 19:41:47 ubuntu kernel: usb 8-1.4.2: SerialNumber: xxxxxxxxxxxxxxx
Jan 05 19:41:47 ubuntu kernel: scsi host2: uas
Jan 05 19:41:47 ubuntu kernel: scsi 2:0:0:0: Direct-Access     Samsung  PSSD T7 Shield   0    PQ: 0 ANSI: 6
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: Attached scsi generic sg1 type 0
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: [sdc] 3907029168 512-byte logical blocks: (2.00 TB/1.82 TiB)
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: [sdc] Write Protect is off
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: [sdc] Mode Sense: 43 00 00 00
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: [sdc] Preferred minimum I/O size 512 bytes
Jan 05 19:41:47 ubuntu kernel: sd 2:0:0:0: [sdc] Optimal transfer size 33553920 bytes
...
Jan 05 19:41:49 ubuntu kernel:  sdc: sdc1
Jan 05 19:41:49 ubuntu kernel: sd 2:0:0:0: [sdc] Attached SCSI disk
Jan 05 19:41:50 ubuntu udisksd[1779]: Mounted /dev/sdc1 at /media/ubuntu/T7 Shield on behalf of uid 999
...
# reproduced the freeze
...
Jan 05 19:42:44 ubuntu kernel: sd 2:0:0:0: [sdc] tag#9 uas_eh_abort_handler 0 uas-tag 2 inflight: CMD IN 
Jan 05 19:42:44 ubuntu kernel: sd 2:0:0:0: [sdc] tag#9 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#28 uas_eh_abort_handler 0 uas-tag 10 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#28 CDB: Read(10) 28 00 1f 98 c1 a0 00 01 08 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#27 uas_eh_abort_handler 0 uas-tag 9 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#27 CDB: Read(10) 28 00 1f 98 bd a0 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#26 uas_eh_abort_handler 0 uas-tag 8 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#26 CDB: Read(10) 28 00 1f 98 b9 a0 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#25 uas_eh_abort_handler 0 uas-tag 6 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#25 CDB: Read(10) 28 00 1f 98 b1 a0 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#24 uas_eh_abort_handler 0 uas-tag 7 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#24 CDB: Read(10) 28 00 1f 98 b5 a0 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#23 uas_eh_abort_handler 0 uas-tag 1 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#23 CDB: Read(10) 28 00 1f 98 a2 88 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#22 uas_eh_abort_handler 0 uas-tag 5 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#22 CDB: Read(10) 28 00 1f 98 ad a0 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#21 uas_eh_abort_handler 0 uas-tag 4 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#21 CDB: Read(10) 28 00 1f 98 aa 88 00 03 18 00
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#20 uas_eh_abort_handler 0 uas-tag 3 inflight: CMD IN 
Jan 05 19:42:56 ubuntu kernel: sd 2:0:0:0: [sdc] tag#20 CDB: Read(10) 28 00 1f 98 a6 88 00 04 00 00
Jan 05 19:42:56 ubuntu kernel: scsi host2: uas_eh_device_reset_handler start
Jan 05 19:42:56 ubuntu kernel: usb 8-1.4.2: reset SuperSpeed Plus Gen 2x1 USB device number 7 using xhci_hcd
Jan 05 19:42:56 ubuntu kernel: scsi host2: uas_eh_device_reset_handler success
Jan 05 19:43:23 ubuntu kernel: usb 8-1.4.2: USB disconnect, device number 7
Jan 05 19:43:23 ubuntu kernel: sd 2:0:0:0: [sdc] tag#7 uas_zap_pending 0 uas-tag 10 inflight: CMD 
Jan 05 19:43:23 ubuntu kernel: sd 2:0:0:0: [sdc] tag#7 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 05 19:43:23 ubuntu kernel: scsi_io_completion_action: 20 callbacks suppressed
Jan 05 19:43:23 ubuntu kernel: sd 2:0:0:0: [sdc] tag#7 FAILED Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK cmd_age=68s
Jan 05 19:43:23 ubuntu kernel: sd 2:0:0:0: [sdc] tag#7 CDB: Read(10) 28 00 1f 98 9e 88 00 04 00 00
Jan 05 19:43:23 ubuntu kernel: blk_print_req_error: 1711 callbacks suppressed
Jan 05 19:43:23 ubuntu kernel: I/O error, dev sdc, sector 530095752 op 0x0:(READ) flags 0x80700 phys_seg 128 prio class 2
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094728 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092680, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094729 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092681, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094730 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092682, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094731 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092683, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094732 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092684, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094733 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092685, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094734 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092686, async page read
Jan 05 19:43:23 ubuntu kernel: device offline error, dev sdc, sector 530094735 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
Jan 05 19:43:23 ubuntu kernel: Buffer I/O error on dev sdc1, logical block 530092687, async page read
Jan 05 19:43:23 ubuntu sudo[8429]: pam_unix(sudo:session): session closed for user root
Jan 05 19:43:23 ubuntu udisksd[1779]: Cleaning up mount point /media/ubuntu/T7 Shield (device 8:33 no longer exists)
Jan 05 19:43:23 ubuntu systemd[1]: media-ubuntu-T7\x20Shield.mount: Deactivated successfully.
Jan 05 19:43:23 ubuntu kernel: sd 2:0:0:0: [sdc] Synchronizing SCSI cache
Jan 05 19:43:23 ubuntu kernel: sd 2:0:0:0: [sdc] Synchronize Cache(10) failed: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK

Appreciate the logs and the testing. I will raise this internally for engineering eyes. Filing an internal ticket now.

For the time being:

FW laptop USB3.2 port <–> Dell WD22TB4 dock <–> PSSD T7 Shield 2TB
FW laptop, any USB port <–> PSSD T7 Shield 2TB

Sounds like it is the path forward.

Edit: Ticket is filed internally.

1 Like

Thanks, I appreciate this.

I’ve got it narrowed down further to a specific 4k block read - SCSI op Read(10) on Logical Block Address (LBA): 530095760 (dec), transfer length 8.
Also got the contents and a USB dump of both successful and unsuccessful attempts. With the buggy TB4 output, the SCSI command to Read(10) is sent to the disk, and the disk sends back β€œURB_BULK out” to the host, but there is no UASP block returned by the disk, and no SCSI response either.

I can upload this somewhere, if you think it would help.

Note that by playing with the block (and writing to it), I somehow managed to wipe my partition table and I had to recover it via testdisk. :grinning: However rewriting the affected block with zeroes has not solved the issue.