Bug 236854

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!