On Fri, Jun 03, 2022 at 03:02:36PM +0200, Theo Buehler wrote:
> > Please do note that this change can introduce/expose other issues.
>
> It seems that this diff causes occasional hangs when building snapshots
> on my mac M1 mini. This happened twice in 10 builds, both times in
> xenocara. Unfortunately, both times the machine became entirely
> unresponsive and as I don't have serial console, that's all the info I
> have...
>
> This machine has been very reliable and built >50 snaps without any hang
> over the last 2.5 months. I'm now trying snap builds in a loop without
> the diff to make sure the machine doesn't hang due to another recent
> kernel change.
>
A little bit of info on this. The first three lines were a bit garbled on
the screen:
panic: kernel diagnostic assertion "uvn->_oppa jai c: ke r el d
iag no tic a s rt n " map == UL L | | rw wr k
ite held(amap->amap_lock)" failed: file "/ss/uvm/uvm_fault.c", line 846.
ernel diagnostic assertion "!_kernel_lock_held
Stopped at panic+0160: cmp w21, #0x0 ailed: file "/sys/kern/
TID PID UID PRFLAGS PFLAGS CPU COMMAND
411910 44540 21 0x100001 0 3 make
*436444 84241 21 0x100003 0 6 sh
227952 53498 21 0x100003 0 5 sh
258925 15765 21 0x101005 0 0 make
128459 9649 21 0x100003 0 1 tradcpp
287213 64216 21 0x100003 0x8 7 make
173587 4617 1000 0x100000 0 2 tmux
126511 69919 0 0x14000 0x200 4 softnet
db_enter() at panic+0x15c
panic() at __assert+0x24
uvm_fault() at uvm_fault_upper_lookup+0x258
uvm_fault_upper() at uvm_fault+0xec
uvm_fault() at udata_abort+0x128
udata_abort() at do_el0_sync+0xdc
do_el0_sync() at handle_el0_sync+0x74
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports. Insufficient info makes it difficult to find and fix bugs.
ddb{6}> show panic
*cpu0: kernel diagnostic assertion "uvn->u_obj.uo_refs == 0" failed: file
"/sys/kern/uvn_vnode.c", line 231.
cpu6: kernel diagnostic assertion "amap == NULL ||
rw_write_held(amap->am_lock)" failed: file "/sys/uvm/uvm_fault", line 846.
cpu3: kernel diagnostic assertion "!_kernel_lock_held()" failed: file
"/sys/kern/kern_fork.c", line 678
ddb{6}> mach ddbcpu 0
After pressing enter here, the machine locked up completely.
