Beginning with kernel 3.15.1, I am getting hard lockups every time I connect a drive to my USB 3 HDD dock with ASMedia ASM1051E UASP compliant chipset. The only way I am able work around this is to set the quirk to ignore uas for the device. Here are the kernel messages during connection followed by a backtrace: [ 229.882190] usb 2-1: new SuperSpeed USB device number 3 using xhci_hcd [ 229.908001] usb-storage 2-1:1.0: USB Mass Storage device detected [ 229.908218] usb-storage 2-1:1.0: Quirks match for vid 174c pid 55aa: 400000 [ 229.908349] scsi7 : usb-storage 2-1:1.0 [ 230.912633] scsi 7:0:0:0: Direct-Access ASMT 2105 0 PQ: 0 ANSI: 6 [ 230.914818] sd 7:0:0:0: [sdc] Attached SCSI removable disk [ 289.680267] usb 2-1: USB disconnect, device number 3 [ 319.599862] usb 2-1: new SuperSpeed USB device number 4 using xhci_hcd [ 319.626881] scsi8 : uas [ 319.628221] xhci_hcd 0000:02:00.0: ERROR Transfer event TRB DMA ptr not part of current TD [ 320.029323] BUG: unable to handle kernel paging request at 0000000001000003 [ 320.029393] IP: [<ffffffff81198b0b>] kmem_cache_alloc+0x6b/0x170 [ 320.029445] PGD 40821a067 PUD 401bbf067 PMD 40411c067 PTE 0 [ 320.029505] Oops: 0000 [#1] PREEMPT SMP [ 320.029552] Modules linked in: uas usb_storage netconsole des_generic ecb md4 nls_utf8 cifs dns_resolver sch_fq_codel fuse nf_conntrack_ipv4 nf_defrag_ipv4 xt_tcpudp xt_conntrack nf_conntrack iptable_filter ip_tables x_tables vmnet(O) vsock vmci(O) vmmon(O) w83627ehf hwmon_vid adm1021 xfs libcrc32c nls_iso8859_1 nls_cp437 vfat fat coretemp hwmon iTCO_wdt intel_rapl iTCO_vendor_support x86_pkg_temp_thermal intel_powerclamp crct10dif_pclmul crc32_pclmul ppdev crc32c_intel snd_hda_codec_hdmi ghash_clmulni_intel aesni_intel snd_hda_codec_realtek snd_hda_codec_generic aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd e1000e hdpvr microcode evdev snd_hda_intel i915 joydev v4l2_dv_timings ptp mousedev psmouse r8168(O) mac_hid snd_hda_controller videodev serio_raw pcspkr media snd_hda_codec i2c_i801 lpc_ich pps_core snd_hwdep drm_kms_helper snd_pcm snd_timer drm snd battery tpm_tis parport_pc tpm intel_gtt parport i2c_algo_bit mei_me soundcore mei nuvoton_cir video shpchp button processor nfsd auth_rpcgss oid_registry nfs_acl nfs lockd fscache sunrpc lirc_zilog(C) i2c_core lirc_dev rc_core ext4 crc16 mbcache jbd2 hid_generic usbhid hid sd_mod crc_t10dif crct10dif_common atkbd libps2 ehci_pci xhci_hcd ehci_hcd firewire_ohci ahci libahci libata firewire_core crc_itu_t scsi_mod usbcore usb_common i8042 serio [ 320.030938] CPU: 0 PID: 782 Comm: mysqld Tainted: G C O 3.15.3-ARCH #1 [ 320.030988] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z68 Pro3-M, BIOS P2.30 06/29/2012 [ 320.031052] task: ffff8800c9488a30 ti: ffff8800cebd8000 task.ti: ffff8800cebd8000 [ 320.031103] RIP: 0010:[<ffffffff81198b0b>] [<ffffffff81198b0b>] kmem_cache_alloc+0x6b/0x170 [ 320.031165] RSP: 0018:ffff8800cebdba78 EFLAGS: 00010082 [ 320.031203] RAX: 0000000000000000 RBX: ffffffffa0118140 RCX: 0000000000833300 [ 320.031251] RDX: 0000000000833280 RSI: 0000000000000020 RDI: ffffffffa00fd04b [ 320.031298] RBP: ffff8800cebdbaa8 R08: 0000000000017560 R09: ffff8803fad57380 [ 320.031346] R10: 000000000000002f R11: ffff8803fad5002f R12: 0000000001000003 [ 320.031394] R13: 0000000000000020 R14: ffff880407af1000 R15: ffff88040ec01900 [ 320.031442] FS: 00007f28c2bff700(0000) GS:ffff88041f200000(0000) knlGS:0000000000000000 [ 320.031496] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 320.031536] CR2: 0000000001000003 CR3: 0000000407474000 CR4: 00000000000407f0 [ 320.031584] Stack: [ 320.031602] ffffffffa00fd030 ffffffffa0118140 ffff8803fad57380 0000000000000020 [ 320.031669] ffff880407af1000 0000000000000020 ffff8800cebdbae0 ffffffffa00fd04b [ 320.031738] ffff8803c8e93780 ffff880407af1000 ffff880407430968 000000000084f7e0 [ 320.031806] Call Trace: [ 320.031839] [<ffffffffa00fd030>] ? scsi_host_alloc_command+0x30/0xd0 [scsi_mod] [ 320.031899] [<ffffffffa00fd04b>] scsi_host_alloc_command+0x4b/0xd0 [scsi_mod] [ 320.031956] [<ffffffffa00fd0e8>] __scsi_get_command+0x18/0xe0 [scsi_mod] [ 320.032009] [<ffffffffa00fd1cb>] scsi_get_command+0x1b/0xd0 [scsi_mod] [ 320.032064] [<ffffffffa0104c74>] scsi_get_cmd_from_req+0x74/0xa0 [scsi_mod] [ 320.032121] [<ffffffffa0105a2d>] scsi_setup_fs_cmnd+0x3d/0xb0 [scsi_mod] [ 320.032173] [<ffffffffa0247c68>] sd_prep_fn+0x3b8/0xd30 [sd_mod] [ 320.032219] [<ffffffff8126a411>] blk_peek_request+0x131/0x280 [ 320.032268] [<ffffffffa0105ade>] scsi_request_fn+0x3e/0x4b0 [scsi_mod] [ 320.032315] [<ffffffff81266853>] __blk_run_queue+0x33/0x40 [ 320.032356] [<ffffffff81267afe>] queue_unplugged+0x2e/0xd0 [ 320.032398] [<ffffffff8126a8dd>] blk_flush_plug_list+0x1ed/0x270 [ 320.032442] [<ffffffff8126ad14>] blk_finish_plug+0x14/0x50 [ 320.032491] [<ffffffffa0303539>] ext4_writepages+0x449/0xd20 [ext4] [ 320.032539] [<ffffffff8114d06e>] do_writepages+0x1e/0x30 [ 320.032579] [<ffffffff8114134d>] __filemap_fdatawrite_range+0x5d/0x80 [ 320.032625] [<ffffffff8114146a>] filemap_write_and_wait_range+0x2a/0x70 [ 320.032680] [<ffffffffa02fa790>] ext4_sync_file+0x110/0x370 [ext4] [ 320.032726] [<ffffffff811e4e8e>] do_fsync+0x4e/0x80 [ 320.032764] [<ffffffff811e5140>] SyS_fsync+0x10/0x20 [ 320.032804] [<ffffffff81515ee9>] system_call_fastpath+0x16/0x1b [ 320.032846] Code: 0f 84 ca 00 00 00 4c 8b 20 4d 85 e4 0f 84 de 00 00 00 48 83 78 10 00 0f 84 d3 00 00 00 49 63 47 20 48 8d 8a 80 00 00 00 4d 8b 07 <49> 8b 1c 04 4c 89 e0 65 49 0f c7 08 0f 94 c0 84 c0 74 a2 49 63 [ 320.033293] RIP [<ffffffff81198b0b>] kmem_cache_alloc+0x6b/0x170 [ 320.033342] RSP <ffff8800cebdba78> [ 320.033369] CR2: 0000000001000003 [ 320.033396] ---[ end trace f435c843a04f8e94 ]--- -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html