Hi, I ran into an issue where I lost the partition information on my MacBook Air this afternoon despite not making any choices in fdisk. I had previously setup my mid 2012 MacBook Air to dual boot with OS X and OpenBSD/amd64 current but lost access to the OpenBSD partition when I enabled file vault. This evening I thought I'd try a new snapshot, so I decrypted the disk by disabling file vault & booted the system off a USB flash drive which I'd written the latest amd64 install58.fs image to. I worked through the installed process and reached the disk selection where I selected the onboard SSD and at which point the screen went blank (I hadn't booted the system in legacy mode via bless) so I power cycled the box with the intent of going back into OS X to bless the system. At this point I discovered I couldn't my system again. Disk utility indicates that the entire disk is now a OpenBSD partition.
I wiped the disk, repartitioned it again from disk utility in OS X with 2 partitions, formatted HFS+ & fat. Reinstalled OS X reinstalled OpenBSD reinstalled refit sync'd GPT & MBR partition table booted into OS X & enabled file vault rebooted & disabled file vault booted off the OpenBSD flash drive went through the installer steps but after choosing the disk to install onto I pressed the power button. (took a photo https://pbs.twimg.com/media/CIx-exfXAAAmC68.jpg:large ) Same thing, disk trashed OpenBSD 5.8-beta (RAMDISK_CD) #1023: Mon Jun 29 13:26:35 MDT 2015 [email protected]:/usr/src/sys/arch/amd64/compile/RAMDISK_CD RTC BIOS diagnostic error b1<clock_battery,config_unit,memory_size> real mem = 8475713536 (8083MB) avail mem = 8217120768 (7836MB) mainbus0 at root bios0 at mainbus0: SMBIOS rev. 2.4 @ 0xe0000 (54 entries) bios0: vendor Apple Inc. version "MBA51.88Z.00EF.B03.1506081623" date 06/08/2015 bios0: Apple Inc. MacBookAir5,1 acpi0 at bios0: rev 2 acpi0: tables DSDT FACP HPET APIC SBST ECDT SSDT SSDT SSDT SSDT SSDT SSDT SSDT SSDT SSDT SSDT SSDT DMAR MCFG acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: Intel(R) Core(TM) i7-3667U CPU @ 2.00GHz, 1895.97 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: apic clock running at 99MHz cpu0: mwait min=64, max=64, C-substates=0.2.1.1.2, IBE cpu at mainbus0: not configured cpu at mainbus0: not configured cpu at mainbus0: not configured ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 20, 24 pins ioapic0: misconfigured as apic 0, remapped to apid 2 acpiec0 at acpi0 acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus -1 (P0P2) acpiprt2 at acpi0: bus -1 (PEG2) acpiprt3 at acpi0: bus 2 (RP02) acpiprt4 at acpi0: bus 3 (RP05) memory map conflict 0xe00f8000/0x1000 memory map conflict 0xfed1c000/0x4000 memory map conflict 0xffe70000/0x30000 pci0 at mainbus0 bus 0 pchb0 at pci0 dev 0 function 0 "Intel Core 3G Host" rev 0x09 vga1 at pci0 dev 2 function 0 "Intel HD Graphics 4000" rev 0x09 wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation) xhci0 at pci0 dev 20 function 0 "Intel 7 Series xHCI" rev 0x04: msi usb0 at xhci0: USB revision 3.0 uhub0 at usb0 "Intel xHCI root hub" rev 3.00/1.00 addr 1 "Intel 7 Series MEI" rev 0x04 at pci0 dev 22 function 0 not configured ehci0 at pci0 dev 26 function 0 "Intel 7 Series USB" rev 0x04: apic 2 int 23 usb1 at ehci0: USB revision 2.0 uhub1 at usb1 "Intel EHCI root hub" rev 2.00/1.00 addr 1 "Intel 7 Series HD Audio" rev 0x04 at pci0 dev 27 function 0 not configured ppb0 at pci0 dev 28 function 0 "Intel 7 Series PCIE" rev 0xc4: msi pci1 at ppb0 bus 1 ppb1 at pci0 dev 28 function 1 "Intel 7 Series PCIE" rev 0xc4: msi pci2 at ppb1 bus 2 "Broadcom BCM43224" rev 0x01 at pci2 dev 0 function 0 not configured ppb2 at pci0 dev 28 function 4 "Intel 7 Series PCIE" rev 0xc4: msi pci3 at ppb2 bus 3 ppb3 at pci3 dev 0 function 0 vendor "Intel", unknown product 0x1547 rev 0x03 pci4 at ppb3 bus 4 ppb4 at pci4 dev 0 function 0 vendor "Intel", unknown product 0x1547 rev 0x03: msi pci5 at ppb4 bus 5 vendor "Intel", unknown product 0x1547 (class system subclass miscellaneous, rev 0x03) at pci5 dev 0 function 0 not configured ppb5 at pci4 dev 3 function 0 vendor "Intel", unknown product 0x1547 rev 0x03: msi pci6 at ppb5 bus 6 ppb6 at pci4 dev 4 function 0 vendor "Intel", unknown product 0x1547 rev 0x03: msi pci7 at ppb6 bus 55 ppb7 at pci4 dev 5 function 0 vendor "Intel", unknown product 0x1547 rev 0x03: msi pci8 at ppb7 bus 104 ppb8 at pci4 dev 6 function 0 vendor "Intel", unknown product 0x1547 rev 0x03: msi pci9 at ppb8 bus 105 ehci1 at pci0 dev 29 function 0 "Intel 7 Series USB" rev 0x04: apic 2 int 22 usb2 at ehci1: USB revision 2.0 uhub2 at usb2 "Intel EHCI root hub" rev 2.00/1.00 addr 1 "Intel QS77 LPC" rev 0x04 at pci0 dev 31 function 0 not configured ahci0 at pci0 dev 31 function 2 "Intel 7 Series AHCI" rev 0x04: msi, AHCI 1.3 ahci0: port 0: 6.0Gb/s scsibus0 at ahci0: 32 targets sd0 at scsibus0 targ 0 lun 0: <ATA, APPLE SSD TS128E, TQAA> SCSI3 0/direct fixed naa.0000000000000000 sd0: 115712MB, 512 bytes/sector, 236978176 sectors, thin "Intel 7 Series SMBus" rev 0x04 at pci0 dev 31 function 3 not configured isa0 at mainbus0 com0 at isa0 port 0x3f8/8 irq 4: ns8250, no fifo umass0 at uhub0 port 1 configuration 1 interface 0 "Generic Mass Storage" rev 2.00/1.03 addr 2 umass0: using SCSI over Bulk-Only scsibus1 at umass0: 2 targets, initiator 0 sd1 at scsibus1 targ 1 lun 0: <Generic, Flash Disk, 8.07> SCSI2 0/direct removable sd1: 1960MB, 512 bytes/sector, 4014080 sectors umass1 at uhub0 port 2 configuration 1 interface 0 "Generic Mass Storage" rev 2.00/1.09 addr 3 umass1: using SCSI over Bulk-Only scsibus2 at umass1: 2 targets, initiator 0 sd2 at scsibus2 targ 1 lun 0: <Generic, Flash Disk, 8.07> SCSI2 0/direct removable sd2: 1921MB, 512 bytes/sector, 3934208 sectors uhub3 at uhub1 port 1 "vendor 0x8087 product 0x0024" rev 2.00/0.00 addr 2 "Apple Inc. FaceTime HD Camera (Built-in)" rev 2.00/80.25 addr 3 at uhub3 port 1 not configured uhub4 at uhub2 port 1 "vendor 0x8087 product 0x0024" rev 2.00/0.00 addr 2 uhub5 at uhub4 port 8 "vendor 0x0424 product 0x2512" rev 2.00/b.b3 addr 3 uhub6 at uhub5 port 1 "Apple Inc. BRCM20702 Hub" rev 2.00/1.00 addr 4 uhidev0 at uhub6 port 1 configuration 1 interface 0 "vendor 0x05ac product 0x820a" rev 2.00/1.00 addr 5 uhidev0: iclass 3/1, 1 report id ukbd0 at uhidev0 reportid 1 wskbd0 at ukbd0: console keyboard, using wsdisplay0 uhidev1 at uhub6 port 2 configuration 1 interface 0 "vendor 0x05ac product 0x820b" rev 2.00/1.00 addr 6 uhidev1: iclass 3/1, 2 report ids uhid at uhidev1 reportid 2 not configured "Apple Inc. Bluetooth USB Host Controller" rev 2.00/1.48 addr 7 at uhub6 port 3 not configured uhidev2 at uhub5 port 2 configuration 1 interface 0 "Apple Inc. Apple Internal Keyboard / Trackpad" rev 2.00/2.19 addr 8 uhidev2: iclass 3/1, 9 report ids ukbd1 at uhidev2 reportid 1 wskbd1 at ukbd1 mux 1 wskbd1: connecting to wsdisplay0 uhid at uhidev2 reportid 9 not configured uhidev3 at uhub5 port 2 configuration 1 interface 1 "Apple Inc. Apple Internal Keyboard / Trackpad" rev 2.00/2.19 addr 8 uhidev3: iclass 3/0, 68 report ids uhid at uhidev3 reportid 68 not configured uhidev4 at uhub5 port 2 configuration 1 interface 2 "Apple Inc. Apple Internal Keyboard / Trackpad" rev 2.00/2.19 addr 8 uhidev4: iclass 3/1, 2 report ids uhid at uhidev4 reportid 2 not configured softraid0 at root scsibus3 at softraid0: 256 targets root on rd0a swap on rd0b dump on rd0b

