Hi! This is not exactly a regression, as I am not aware of a prior working state, but kernel documentation advises me to CC regressions list anyway¹. I am trying to put data on an external Kingston XS-2000 4 TB SSD using self-compiled Linux 6.7.4 kernel and encrypted BCacheFS. I do not think BCacheFS has any part in the errors I see, but if you disagree feel free to CC the BCacheFS mailing list as you reply. I am using a ThinkPad T14 AMD Gen 1 with AMD Ryzen 7 PRO 4750U and 32 GiB of RAM. I connected the SSD onto USB-C port directly with the ThinkPad. lsusb lists it as: Bus 007 Device 004: ID 0951:176b Kingston Technology XS2000 The SSD is detected as follows: [20303.913644] usb 7-1: new SuperSpeed Plus Gen 2x1 USB device number 9 using xhci_hcd [20303.926616] usb 7-1: New USB device found, idVendor=0951, idProduct=176b, bcdDevice= 1.00 [20303.926633] usb 7-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [20303.926641] usb 7-1: Product: XS2000 [20303.926647] usb 7-1: Manufacturer: Kingston [20303.926652] usb 7-1: SerialNumber: […] [20303.929078] scsi host0: uas [20303.983859] scsi 0:0:0:0: Direct-Access Kingston XS2000 1000 PQ: 0 ANSI: 6 [20303.984426] sd 0:0:0:0: Attached scsi generic sg0 type 0 [20303.985197] sd 0:0:0:0: [sda] 8001573552 512-byte logical blocks: (4.10 TB/3.73 TiB) [20303.985331] sd 0:0:0:0: [sda] Write Protect is off [20303.985341] sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00 [20303.985579] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA [20303.989516] sda: sda1 [20303.989611] sd 0:0:0:0: [sda] Attached SCSI disk BCacheFS is mounted as follows – but I suspect BCacheFS is not involved in those errors anyway: [20310.437864] bcachefs (sda1): mounting version 1.3: rebalance_work opts=metadata_checksum=xxhash,data_checksum=xxhash,compression=lz4 [20310.437895] bcachefs (sda1): recovering from clean shutdown, journal seq 5094 [20310.450813] bcachefs (sda1): alloc_read... done [20310.450851] bcachefs (sda1): stripes_read... done [20310.450855] bcachefs (sda1): snapshots_read... done [20310.470815] bcachefs (sda1): journal_replay... done [20310.470824] bcachefs (sda1): resume_logged_ops... done [20310.470835] bcachefs (sda1): going read-write During rsync'ing about 1,4 TB of data after eventually a hour I got things like this: [33963.462694] sd 0:0:0:0: [sda] tag#10 uas_zap_pending 0 uas-tag 1 inflight: CMD [33963.462708] sd 0:0:0:0: [sda] tag#10 CDB: Write(16) 8a 00 00 00 00 00 82 c1 bc 00 00 00 04 00 00 00 [33963.462718] sd 0:0:0:0: [sda] tag#11 uas_zap_pending 0 uas-tag 2 inflight: CMD [33963.462725] sd 0:0:0:0: [sda] tag#11 CDB: Write(16) 8a 00 00 00 00 00 82 c1 c8 00 00 00 04 00 00 00 [33963.462733] sd 0:0:0:0: [sda] tag#15 uas_zap_pending 0 uas-tag 3 inflight: CMD [33963.462740] sd 0:0:0:0: [sda] tag#15 CDB: Write(16) 8a 00 00 00 00 00 82 c1 d2 4c 00 00 01 2f 00 00 [33963.462748] sd 0:0:0:0: [sda] tag#12 uas_zap_pending 0 uas-tag 4 inflight: CMD [33963.462754] sd 0:0:0:0: [sda] tag#12 CDB: Write(16) 8a 00 00 00 00 00 82 c1 d0 00 00 00 02 4c 00 00 [33963.462762] sd 0:0:0:0: [sda] tag#13 uas_zap_pending 0 uas-tag 5 inflight: CMD [33963.462769] sd 0:0:0:0: [sda] tag#13 CDB: Write(16) 8a 00 00 00 00 00 82 c1 d4 00 00 00 00 ff 00 00 [33963.462777] sd 0:0:0:0: [sda] tag#14 uas_zap_pending 0 uas-tag 6 inflight: CMD [33963.462783] sd 0:0:0:0: [sda] tag#14 CDB: Write(16) 8a 00 00 00 00 00 82 c1 ce 00 00 00 00 cc 00 00 [33963.576991] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 9 using xhci_hcd [33963.590793] scsi host0: uas_eh_device_reset_handler success [33963.592857] sd 0:0:0:0: [sda] tag#10 timing out command, waited 180s [33963.592872] sd 0:0:0:0: [sda] tag#10 FAILED Result: hostbyte=DID_RESET driverbyte=DRIVER_OK cmd_age=182s [33963.592881] sd 0:0:0:0: [sda] tag#10 CDB: Write(16) 8a 00 00 00 00 00 82 c1 bc 00 00 00 04 00 00 00 [33963.592886] I/O error, dev sda, sector 2193734656 op 0x1:(WRITE) flags 0x104000 phys_seg 773 prio class 2 [33963.592898] bcachefs (sda1 inum 1073761281 offset 265216): data write error: I/O [33963.592925] bcachefs (sda1 inum 1073761281 offset 467456): data write error: I/O [33963.592933] bcachefs (sda1 inum 1073761281 offset 470016): data write error: I/O [33963.592939] bcachefs (sda1 inum 1073761281 offset 471552): data write error: I/O [33963.592949] bcachefs (sda1 inum 1073761281 offset 514560): data write error: I/O [33963.592956] bcachefs (sda1 inum 1073761281 offset 517120): data write error: I/O [33963.592963] bcachefs (sda1 inum 1073761281 offset 519168): data write error: I/O [33963.592969] bcachefs (sda1 inum 1073761281 offset 521728): data write error: I/O [33963.592976] bcachefs (sda1 inum 1073761281 offset 523776): data write error: I/O [33963.592983] bcachefs (sda1 inum 1073761281 offset 526336): data write error: I/O The rsync completed but I did not trust the result, even tough "bcachefs fsck" told me the filesystem structure is okay. Thus I reran rsync with option "-c" for checksumming. After a long time with data that did match, it started to transfer a file again which should not happen if data would have been identical. As it ran into I/O errors again, I stopped the rsync process. I looked for that UAS error message and according to the article² I found I disabled UAS as follows: % cat /etc/modprobe.d/disable-uas.conf # Does not work with external SSD Transcend XS2000 4TB options usb-storage quirks=0951:176b:u The quirk was applied as I reconnected the devices after unloading both usb-storage and uas modules: [ 55.871301] usb 7-1: UAS is ignored for this device, using usb-storage instead [ 55.871310] usb-storage 7-1:1.0: USB Mass Storage device detected [ 55.871559] usb-storage 7-1:1.0: Quirks match for vid 0951 pid 176b: 800000 I recreated the BCacheFS filesystem and tried again. This time it did not take more than 10 minutes for the first I/O error to appear. Unless with UAS it made rsync stop with an I/O error immediately. Before that there were several USB resets. Here is the excerpt from dmesg: [ 795.768306] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 932.976677] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 963.189438] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 1000.057333] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 1036.917137] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 1073.782876] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 1110.647786] usb 7-1: reset SuperSpeed Plus Gen 2x1 USB device number 4 using xhci_hcd [ 1117.163693] sd 0:0:0:0: [sda] tag#0 FAILED Result: hostbyte=DID_ABORT driverbyte=DRIVER_OK cmd_age=214s [ 1117.163718] sd 0:0:0:0: [sda] tag#0 CDB: Write(16) 8a 00 00 00 00 00 02 72 20 00 00 00 08 00 00 00 [ 1117.163725] I/O error, dev sda, sector 41033728 op 0x1:(WRITE) flags 0x104000 phys_seg 1551 prio class 2 [ 1117.163739] bcachefs (sda1 inum 1879048481 offset 2572800): data write error: I/O [ 1117.163763] bcachefs (sda1 inum 1879048481 offset 2576384): data write error: I/O [ 1117.163771] bcachefs (sda1 inum 1879048481 offset 2578432): data write error: I/O [ 1117.163779] bcachefs (sda1 inum 1879048481 offset 2580480): data write error: I/O [ 1117.163786] bcachefs (sda1 inum 1879048481 offset 2582528): data write error: I/O [ 1117.163794] bcachefs (sda1 inum 1879048481 offset 2584576): data write error: I/O [ 1117.163803] bcachefs (sda1 inum 1879048481 offset 2586624): data write error: I/O [ 1117.163811] bcachefs (sda1 inum 1879048481 offset 2588672): data write error: I/O [ 1117.163818] bcachefs (sda1 inum 1879048481 offset 2590720): data write error: I/O [ 1117.163824] bcachefs (sda1 inum 1879048481 offset 2592768): data write error: I/O So even without UAS the device does not seem to like to write data on Linux. Next steps may involve looking for a firmware update for the external SSD as well as trying to obtain its SMART status. So far I did not succeed in finding the right options for smartctl. In case there is enough evidence that the device is defective I'd try to RMA it. I will keep a copy of kernel log and I could do some further tests as time permits. So let me know whether you need anything else, but for now the mail is long enough as it is. [1] https://www.kernel.org/doc/html/latest/admin-guide/reporting-issues.html [2] How to disable USB Attached Storage (UAS) Last edited on 4 December 2022, at 14:00 https://leo.leung.xyz/wiki/How_to_disable_USB_Attached_Storage_(UAS) Ciao, -- Martin
