Hello! I have seen strange situation during of system boot when rootfs should be mounted on /dev/md0 (ramdisk): When system starts to boot into loaded kernel there is the following exception: FreeBSD/amd64 EFI loader, Revision 1.1 (Fri Jun 22 04:20:29 UTC 2018 root@releng2.nyi.freebsd.org) Load Path: HD(2,GPT,56BFC0A5-33B0-11E9-9FAC-A4BF012E952E,0x64028,0x139BFF8) Load Device: PciRoot(0x9)/Pci(0x0,0x0)/Pci(0x0,0x0)/Ctrl(0x1)/Scsi(0x6,0x0)/H Btart @ 0xffffffff80310000 ...s, 'help' for more detailed help.rompt.x16aee0+0x8 !!!! X64 Exception Type - 0D(#GP - General Protection) CPU Apic ID - 00000000 !!!! RIP - 000000005B869C63, CS - 0000000000000038, RFLAGS - 0000000000010206 ExceptionData - 0000000000000000 RAX - 0000000000000002, RCX - 0000000000000000, RDX - 2E36E95DE5894855 RBX - 0000000000000000, RSP - 000000006C0D2D58, RBP - 000000006C0D2E50 RSI - 000000005B899778, RDI - 000000005B88AC30 R8 - 00000000FFFFFFFB, R9 - 8080808080808080, R10 - 00000000FFFFFFF8 R11 - 000000006C0D2AE0, R12 - 000000005B88F210, R13 - 000000005B89D6D8 R14 - 000000005B88F200, R15 - 0000000000000002 DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030 GS - 0000000000000030, SS - 0000000000000030 CR0 - 0000000080000013, CR2 - 0000000000000000, CR3 - 000000006C033000 CR4 - 0000000000000668, CR8 - 0000000000000000 DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000 DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400 GDTR - 000000006A510DE0 0000000000000047, LDTR - 0000000000000000 IDTR - 000000006A509018 0000000000000FFF, TR - 0000000000000000 FXSAVE_STATE - 000000006C0D29B0 !!!! Find PE image (No PDB) (ImageBase=000000005B843000, EntryPoint=000000005B849E50) !!!! [closing the connection] I catched it via SOL (Serial over LAN). Could you please help me to know - is this a bug or maybe i forget about some specific settings? My /boot/loader.conf looks like: # old style beastie_disable="YES" # system mrsas_load="YES" geom_mirror_load="YES" # rootfs on ramdisk initmd_load="YES" initmd_type="md_image" initmd_name="/boot/boot.md" #100MB file size rootdev="ufs:/dev/md0" I'm booting with UEFI support. My kernel is GENERIC but i recompiled it without mrsas driver. I load the driver via kernel module compiled from fresh sources downloaded from MegaRAID site manufacturer. The log of this driver looks like: AVAGO MegaRAID SAS FreeBSD mrsas driver version: 07.708.02.00 mrsas0: <AVAGO Tomcat SAS Controller> port 0xf000-0xf0ff mem 0x39fffff00000-0x39ffffffffff,0x39ffffe00000-0x39ffffefffff,0xee800000-0xee8fffff at device 0.0 numa-domain 1 on pci11 mrsas0: Using MSI-X with 40 number of vectors mrsas0: FW supports <128> MSIX vector,Online CPU 40 Current MSIX <40> mrsas0: NVME page size : (4096) mrsas0: FW supports SED mrsas0: FW supports JBOD Map mrsas0: FW supports JBOD Map Ext mrsas0: Jbod map is supported mrsas0: System PD created target ID: 0x6 mrsas0: System PD created target ID: 0x7 mrsas0: System PD created target ID: 0x8 mrsas0: System PD created target ID: 0x9 mrsas0: MSI-x interrupts setup success And i use GEOM mirror. When i remove the strings from /boot/loader.conf: # rootfs on ramdisk initmd_load="YES" initmd_type="md_image" initmd_name="/boot/boot.md" rootdev="ufs:/dev/md0" - then my system boots as usual. Thank you for helpl in advance!