OK more specifics,
I repeated my tests from last night and the boot does indeed fail after
revision 1.35 on sys/arch/sparc64/stand/ofboot/boot.c
Random was added to the bootblocks before 6.7. But then code was
added to fchmod the random file, so that it would not be reused.
That fchmod is a write-to-disk operation.
Rebooting with command: boot
Boot device: disk File and args:
OpenBSD IEEE 1275 Bootblock 2.0
..>> OpenBSD BOOT 1.19
Trying bsd...
/
Evaluating:
Flushbuf error
read header: short read (only 0 of 64)
Is this write code triggering a bug in the bootblocks or is it actually
broken on it's own?
see loadrandom()
the fchmod call is what's triggers the error, I don't know the answer to
your question though.
I have to step away for the evening but for those who are interested
here is the process I used today and a similar one yesterday to
determine when the problem was introduced.
Process
=======
On separate NFS machine to prevent downloading entire tree every test
Checkout openbsd cvs src using
cvs -q checkout -PD"<date>" src
Update source to specific date using from inside the src directory
cvs -q up -PdD"2020-05-26 16:35 UTC"
1. Install OpenBSD snapshot
- Before first boot, switch to shell and download ofwboot from
http://cdn.openbsd.org/pub/OpenBSD/6.7/sparc64/
- replace the ofwboot file on the new root fs (/mnt when in bsd.rd)
2. boot new install
3. umount /usr/src (default)
4. mount <NFSPATH> /usr/src
5. cd /usr/src/sys
6. make obj
7. cd arch/sparc64/stand
8. make
9. make install
10. installboot -v wd0
11. reboot
Checking "2020-06-05 09:15 UTC"
- This patch is just before Otto introduced bootblock 2.1
Result : Failure, fault introduced before this change
----
Bisecting date between 2020-06-05 and 2020-05-26
Checking 2020-06-01
Result : Failure, fault introduced before this date
----
Bisecting date between 2020-05-26 and 2020-06-01
Checking 2020-05-28
Result : Failure, fault introduced before this date
----
Bisecting date between 2020-05-26 and 2020-05-28
Checking 2020-05-27
Result : Failure, fault introduced before this date
----
Resetting to 2020-05-26
Checking 2020-05-26
Result : Boots
----
Updating to "2020-05-26 16:29 UTC"
Result : Boots
----
Updating to "2020-05-26 16:35 UTC"
Result : Fault
introduced/triggered at R1.35 on sys/arch/sparc64/stand/ofboot/boot.c
--
Ted Bullock <tbull...@comlore.com>
