Hi,
I ran into the following panic on my Raspberry Pi Zero2W when compiling
the kernel on a 2026-01-11 snapshot. Unfortunately, I do not know how to
fix this.
- Christian
panic: assertwaitok: non-zero mutex count: 1
Stopped at db_enter+0x18: brk #0xf000
TID PID UID PRFLAGS PFLAGS CPU COMMAND
433851 76208 1000 0x3 0 0 ccache
*156464 96163 1000 0x3 0 2 cc
147282 40014 1000 0x3 0 1 cc
121706 68538 0 0x14000 0x200 3 sdmmc0
db_enter() at panic+0x138
panic() at assertwaitok+0xb8
assertwaitok() at pool_get+0x34
pool_get() at uvm_mapent_alloc+0x20c
uvm_mapent_alloc() at uvm_map_clip_start+0x80
uvm_map_clip_start() at uvm_unmap_remove+0x248
uvm_unmap_remove() at uvm_unmap+0x64
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{2}> trace
db_enter() at panic+0x138
panic() at assertwaitok+0xb8
assertwaitok() at pool_get+0x34
pool_get() at uvm_mapent_alloc+0x20c
uvm_mapent_alloc() at uvm_map_clip_start+0x80
uvm_map_clip_start() at uvm_unmap_remove+0x248
uvm_unmap_remove() at uvm_unmap+0x64
uvm_unmap() at km_free+0x50
km_free() at pool_p_alloc+0x1f4
pool_p_alloc() at pool_do_get+0x20c
pool_do_get() at pool_get+0x8c
pool_get() at pmap_vp_enter+0x17c
pmap_vp_enter() at pmap_enter+0x1ac
pmap_enter() at uvm_fault_lower+0x220
uvm_fault_lower() at uvm_fault+0x158
uvm_fault() at udata_abort+0x128
udata_abort() at do_el0_sync+0x100
do_el0_sync() at handle_el0_sync+0x70
handle_el0_sync() at __ALIGN_SIZE+0x4b689f8
--- trap ---
end of kernel
ddb{2}> show uvm
Current UVM status:
pagesize=4096 (0x1000), pagemask=0xfff, pageshift=12
101363 VM pages: 42267 active, 18301 inactive, 1 wired, 7 free (1 zero)
freemin=3378, free-target=4504, inactive-target=20000, wired-max=33787
faults=10832044, traps=74264382, intrs=2185293, ctxswitch=1898507 fpuswitch=0
softint=881358, syscalls=54181390, kmapent=15
fault counts:
noram=46834246, noanon=0, noamap=0, pgwait=0, pgrele=0
relocks=135632(521), upgrades=454828(1009) anget(retries)=5338133(0),
amapcopy=1590537
neighbor anon/obj pg=2294476/7526313, gets(lock/unlock)=2493095/137450
cases: anon=4664089, anoncow=674044, obj=2156623, prcopy=333643,
przero=3003868
daemon and swap counts:
woke=24230, revs=241, scans=14585, obscans=5500, anscans=9078
busy=0, freed=6930, reactivate=0, deactivate=22337
pageouts=376, pending=375, nswget=0
nswapdev=1
swpages=2097152, swpginuse=5995, swpgonly=3083 paging=16
kernel pointers:
objs(kern)=0xffffff80012aae08
