Hi, I was using a USB->Serial converter on my x240t:
uplcom0 at uhub3 port 1 "Prolific Technology PL2303 Serial" rev 1.10/2.02 addr3 I got the following panic (typed by hand, so beware of typos): ---8<--- usbd_free_xfer: xfer=0xfffffff041cdb3e70 not free splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 splassert: assertwaitok: want 0 have 5 kernel: protection fault trap, code=0 Stopped at ehci_check_intr+0xf: movq 0(%rax),$rax ehci_check_intr() at ehci_check_intr+0xf ehci_softintr() at ehci_softintr+0x43 softintr_dispatch() at softintr_dispatch+0x8b Xsoftnet() at Xsoftnet+0x1f --- interrupt --- (null)() at 0xffffff041ddd30c VOP_FSYNC() at VOP_FSYNC+0x3c sys_fsync() at sys_fsync+0x86 syscall() at syscall+0x368 --- syscall (number 95) --- end of kernel end trace frame: 0x1ae2bbfd2000 0x1ae329c77ba: --->8--- The crash occurred shortly after I had unplugged and re-plugged the USB->serial adapter: I had a getty on ttyU0 which was locking the line, and I wanted to use it for something else (I've since removed the line in /etc/ttys). I guess the kernel doesn't like this device to disappear. Cheers. Full dmesg for x240t follows: ---8<--- OpenBSD 5.9 (GENERIC.MP) #1880: Sat Feb 20 16:48:33 MST 2016 dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP real mem = 16844521472 (16064MB) avail mem = 16329818112 (15573MB) mpath0 at root scsibus0 at mpath0: 256 targets mainbus0 at root bios0 at mainbus0: SMBIOS rev. 2.7 @ 0xdae9c000 (68 entries) bios0: vendor LENOVO version "GCETA2WW (2.62 )" date 04/09/2015 bios0: LENOVO 3437CTO acpi0 at bios0: rev 2 acpi0: sleep states S0 S3 S4 S5 acpi0: tables DSDT FACP SLIC TCPA SSDT SSDT SSDT HPET APIC MCFG ECDT FPDT ASF! UEFI UEFI POAT SSDT SSDT DMAR UEFI DBG2 acpi0: wakeup devices LID_(S4) SLPB(S3) IGBE(S4) EXP3(S4) XHCI(S3) EHC1(S3) EHC2(S3) HDEF(S4) acpitimer0 at acpi0: 3579545 Hz, 24 bits acpihpet0 at acpi0: 14318179 Hz acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: Intel(R) Core(TM) i5-3320M CPU @ 2.60GHz, 2594.60 MHz cpu0: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,F16C,RDRAND,NXE,LONG,LAHF,PERF,ITSC,FSGSBASE,SMEP,ERMS,SENSOR,ARAT cpu0: 256KB 64b/line 8-way L2 cache cpu0: smt 0, core 0, package 0 mtrr: Pentium Pro MTRR support, 10 var ranges, 88 fixed ranges cpu0: apic clock running at 99MHz cpu0: mwait min=64, max=64, C-substates=0.2.1.1.2, IBE cpu1 at mainbus0: apid 2 (application processor) cpu1: Intel(R) Core(TM) i5-3320M CPU @ 2.60GHz, 2594.11 MHz cpu1: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,F16C,RDRAND,NXE,LONG,LAHF,PERF,ITSC,FSGSBASE,SMEP,ERMS,SENSOR,ARAT cpu1: 256KB 64b/line 8-way L2 cache cpu1: smt 0, core 1, package 0 ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 20, 24 pins acpimcfg0 at acpi0 addr 0xf8000000, bus 0-63 acpiec0 at acpi0 acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus -1 (PEG_) acpiprt2 at acpi0: bus 2 (EXP1) acpiprt3 at acpi0: bus 3 (EXP2) acpiprt4 at acpi0: bus 4 (EXP3) acpicpu0 at acpi0: C2(350@80 mwait.1@0x20), C1(1000@1 mwait.1), PSS acpicpu1 at acpi0: C2(350@80 mwait.1@0x20), C1(1000@1 mwait.1), PSS acpipwrres0 at acpi0: PUBS, resource for XHCI, EHC1, EHC2 acpitz0 at acpi0: critical temperature is 103 degC acpibtn0 at acpi0: LID_ acpibtn1 at acpi0: SLPB acpibat0 at acpi0: BAT0 model "45N1077" serial 14278 type LION oem "SANYO" acpibat1 at acpi0: BAT1 not present acpiac0 at acpi0: AC unit online acpithinkpad0 at acpi0 acpidock0 at acpi0: GDCK docked (15) cpu0: Enhanced SpeedStep 2594 MHz: speeds: 2601, 2600, 2500, 2400, 2300, 2200, 2100, 2000, 1900, 1800, 1700, 1600, 1500, 1400, 1300, 1200 MHz pci0 at mainbus0 bus 0 pchb0 at pci0 dev 0 function 0 "Intel Core 3G Host" rev 0x09 inteldrm0 at pci0 dev 2 function 0 "Intel HD Graphics 4000" rev 0x09 drm0 at inteldrm0 inteldrm0: msi inteldrm0: 1366x768 wsdisplay0 at inteldrm0 mux 1: console (std, vt100 emulation) wsdisplay0: screen 1-5 added (std, vt100 emulation) "Intel 7 Series MEI" rev 0x04 at pci0 dev 22 function 0 not configured em0 at pci0 dev 25 function 0 "Intel 82579LM" rev 0x04: msi, address 3c:97:0e:a5:02:69 ehci0 at pci0 dev 26 function 0 "Intel 7 Series USB" rev 0x04: apic 2 int 16 usb0 at ehci0: USB revision 2.0 uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1 azalia0 at pci0 dev 27 function 0 "Intel 7 Series HD Audio" rev 0x04: msi azalia0: codecs: Realtek ALC269, Intel/0x2806, using Realtek ALC269 audio0 at azalia0 ppb0 at pci0 dev 28 function 0 "Intel 7 Series PCIE" rev 0xc4: msi pci1 at ppb0 bus 2 sdhc0 at pci1 dev 0 function 0 "Ricoh 5U822 SD/MMC" rev 0x07: apic 2 int 16 sdmmc0 at sdhc0 ppb1 at pci0 dev 28 function 1 "Intel 7 Series PCIE" rev 0xc4: msi pci2 at ppb1 bus 3 iwn0 at pci2 dev 0 function 0 "Intel Centrino Wireless-N 2200" rev 0xc4: msi, MIMO 2T2R, BGN, address 9c:4e:36:b8:f8:f8 ppb2 at pci0 dev 28 function 2 "Intel 7 Series PCIE" rev 0xc4: msi pci3 at ppb2 bus 4 ehci1 at pci0 dev 29 function 0 "Intel 7 Series USB" rev 0x04: apic 2 int 23 usb1 at ehci1: USB revision 2.0 uhub1 at usb1 "Intel EHCI root hub" rev 2.00/1.00 addr 1 pcib0 at pci0 dev 31 function 0 "Intel QM77 LPC" rev 0x04 ahci0 at pci0 dev 31 function 2 "Intel 7 Series AHCI" rev 0x04: msi, AHCI 1.3 ahci0: port 0: 6.0Gb/s ahci0: port 1: 1.5Gb/s scsibus1 at ahci0: 32 targets sd0 at scsibus1 targ 0 lun 0: <ATA, Crucial_CT240M50, MU02> SCSI3 0/direct fixed naa.500a0751093c44b5 sd0: 228936MB, 512 bytes/sector, 468862128 sectors, thin cd0 at scsibus1 targ 1 lun 0: <MATSHITA, DVD-RAM UJ8C2, SB01> ATAPI 5/cdrom removable ichiic0 at pci0 dev 31 function 3 "Intel 7 Series SMBus" rev 0x04: apic 2 int 18 iic0 at ichiic0 spdmem0 at iic0 addr 0x50: 8GB DDR3 SDRAM PC3-12800 SO-DIMM spdmem1 at iic0 addr 0x51: 8GB DDR3 SDRAM PC3-12800 SO-DIMM isa0 at pcib0 isadma0 at isa0 pckbc0 at isa0 port 0x60/5 irq 1 irq 12 pckbd0 at pckbc0 (kbd slot) wskbd0 at pckbd0: console keyboard, using wsdisplay0 pms0 at pckbc0 (aux slot) wsmouse0 at pms0 mux 0 pcppi0 at isa0 port 0x61 spkr0 at pcppi0 uhub2 at uhub0 port 1 "Intel Rate Matching Hub" rev 2.00/0.00 addr 2 uhidev0 at uhub2 port 2 configuration 1 interface 0 "Logitech USB Receiver" rev 2.00/12.01 addr 3 uhidev0: iclass 3/1 ukbd0 at uhidev0: 8 variable keys, 6 key codes wskbd1 at ukbd0 mux 1 wskbd1: connecting to wsdisplay0 uhidev1 at uhub2 port 2 configuration 1 interface 1 "Logitech USB Receiver" rev 2.00/12.01 addr 3 uhidev1: iclass 3/1, 8 report ids ums0 at uhidev1 reportid 2: 16 buttons, Z and W dir wsmouse1 at ums0 mux 0 uhid0 at uhidev1 reportid 3: input=4, output=0, feature=0 uhid1 at uhidev1 reportid 4: input=1, output=0, feature=0 uhid2 at uhidev1 reportid 8: input=1, output=0, feature=0 uhidev2 at uhub2 port 2 configuration 1 interface 2 "Logitech USB Receiver" rev 2.00/12.01 addr 3 uhidev2: iclass 3/0, 33 report ids uhid3 at uhidev2 reportid 16: input=6, output=6, feature=0 uhid4 at uhidev2 reportid 17: input=19, output=19, feature=0 uhid5 at uhidev2 reportid 32: input=14, output=14, feature=0 uhid6 at uhidev2 reportid 33: input=31, output=31, feature=0 ugen0 at uhub2 port 4 "Broadcom Corp BCM20702A0" rev 2.00/1.12 addr 4 uvideo0 at uhub2 port 6 configuration 1 interface 0 "Chicony Electronics Co., Ltd. Integrated Camera" rev 2.00/5.20 addr 5 video0 at uvideo0 uhub3 at uhub1 port 1 "Intel Rate Matching Hub" rev 2.00/0.00 addr 2 uplcom0 at uhub3 port 2 "Prolific Technology PL2303 Serial" rev 1.10/2.02 addr 3 ucom0 at uplcom0 uhub4 at uhub3 port 3 "Standard Microsystems product 0x2514" rev 2.00/0.00 addr 4 uhidev3 at uhub4 port 1 configuration 1 interface 0 "SEJIN SEJIN USB joint Keyboard" rev 1.10/1.30 addr 5 uhidev3: iclass 3/1 ukbd1 at uhidev3: 8 variable keys, 6 key codes wskbd2 at ukbd1 mux 1 wskbd2: connecting to wsdisplay0 uhidev4 at uhub3 port 5 configuration 1 interface 0 "Tablet ISD-V4" rev 1.10/6.11 addr 6 uhidev4: iclass 3/1, 2 report ids ums1 at uhidev4 reportid 1: 2 buttons wsmouse2 at ums1 mux 0 ums2 at uhidev4 reportid 2: 3 buttons, tip, barrel, eraser wsmouse3 at ums2 mux 0 vscsi0 at root scsibus2 at vscsi0: 256 targets softraid0 at root scsibus3 at softraid0: 256 targets root on sd0a (a81068940d057f4c.a) swap on sd0b dump on sd0b --->8--- -- Best Regards Edd Barrett http://www.theunixzoo.co.uk