"machine mem" takes an optional argument to either restrict max memory, or
add/remove certain ranges - https://man.openbsd.org/amd64/boot#memory - you
could try excluding some of the memory ranges from the list you showed.
--
Sent from a phone, apologies for poor formatting.
On 5 September 2025 01:02:28 Ignacio Valdez <[email protected]> wrote:
OpenBSD Bug Report - HP EliteDesk 800 G6 SFF Boot Hang
Hardware Information
System: HP EliteDesk 800 G6 SFF (manufactured 2020)
Architecture: amd64
Boot Mode: UEFI only (no Legacy/CSM option available)
Memory: 16GB+ (16548068KB total free memory reported)
Problem Description
OpenBSD consistently hangs during boot with the message "entry point at
0x1001000" on this hardware. The system boots successfully with FreeBSD and
other operating systems.
Versions Tested
All exhibit the same behavior:
OpenBSD 7.7 (miniroot77.img)
OpenBSD 7.4
OpenBSD 6.9
Current snapshots
Troubleshooting Attempted
Boot options tried:
boot -s (single user)
boot -v (verbose)
boot -c (UKC mode)
boot -d (debugger)
Bootloader replacement:
Replaced BOOTX64.EFI with version from OpenBSD 6.6
No change in behavior
UEFI/BIOS settings:
Disabled Secure Boot
Tried different SATA modes (AHCI vs Intel RST)
Various other firmware settings
Note: No Legacy boot option available
Memory Map Information
Output from mach mem command at boot prompt:
probing: pc0 mem[635K 2830M 200K 281M 13048M]
disk: hd0 hd1*
OpenBSD/amd64 BOOTX64 3.67
boot> mach mem
Region 0: type 1 at 0x0 for 636KB
Region 1: type 2 at 0x9f000 for 388KB
Region 2: type 1 at 0x100000 for 2898324KB
Region 3: type 4 at 0xb0f65000 for 4KB
Region 4: type 1 at 0xb0f66000 for 200KB
Region 5: type 2 at 0xb0f98000 for 4KB
Region 6: type 1 at 0xb0f99000 for 287752KB
Region 7: type 2 at 0xc289b000 for 21392KB
Region 8: type 4 at 0xc3d7f000 for 204KB
Region 9: type 3 at 0xc3f7f000 for 512KB
Region 10: type 1 at 0xc3fff000 for 4KB
Region 11: type 1 at 0x100000000 for 13361152KB
Region 12: type 2 at 0xc4000000 for 139264KB
Region 13: type 2 at 0xff000000 for 16384KB
Low ram: 1024KB High ram: 3349504KB
Total free memory: 16548006KB
Key Observations
Boot hangs at 0x1001000, which is just after Region 2 (type 1 at 0x100000)
Kernel size is 4.6MB (well under reported 18MB UEFI limits)
System has adequate memory (16GB+)
This appears to be a UEFI memory allocation issue similar to reported
problems on other recent HP business machines
Similar Reports Found
This issue appears related to other reports on HP Elitebook 840 G10 and
similar UEFI-only HP business machines from 2020+ that lack Legacy boot
support.
Workaround Status
No successful workarounds found. FreeBSD installs and runs successfully on
the same hardware, confirming the system is functional.
Request
This represents a significant compatibility issue with common business
hardware. Any guidance on:
Additional debugging steps
Potential UEFI bootloader fixes
Timeline for addressing this class of UEFI compatibility issues
Would be greatly appreciated.
Reported by: Ignacio Valdez
Email: [email protected]
