From: Jeremie Courreges-Anglas Subject: Re: Please test: parallel fault handling To: tech@openbsd.org Date: Thu, 22 May 2025 18:54:08 +0200 On Mon, May 19, 2025 at 09:23:27PM +0200, Jeremie Courreges-Anglas wrote: > On Tue, May 13, 2025 at 02:28:08PM +0200, Martin Pieuchot wrote: > > On 13/05/25(Tue) 13:57, Jeremie Courreges-Anglas wrote: > [...] > > > The sparc64 LDOM went into two panics - I somehow managed to break it > > > out of ddb after the first panic due to bogus conserver. The data > > > below is minimal, sorry, I didn't recover the full trace from dmesg > > > after the 1st panic, and 'mach ddbcpu 0' locked up during the 2nd > > > panic. > > > > I wonder if sparc64's pmap is in need for some love... > > > > > > > > I had not run a sparc64 bulk build on this machine in the recent > > > months, and I don't know whether both panics are related to your diff, > > > but I'll do my best to try and reproduce them. Currently I've > > > restarted the bulk build without the uvm change. Maybe someone with > > > more sparc64 knowledge will bring some clue here. > > > > Please let me know. > > I can already tell that this LDOM ran the rest of the bulk with the > parallel uvm fault diff reverted... Now restarting another build from > scratch, with your diff on top of -current. > > > You can also start by "ps /o" or "show proc". > > Hopefully that will be enough! mach ddbcpu x didn't seem very usable. *Bzzzt* The same LDOM was busy compiling two devel/llvm copies under dpb(1). Input welcome, I'm not sure yet what other ddb commands could help. login: panic: trap type 0x34 (mem address not aligned): pc=1012f68 npc=1012f6c pstate=820006 Stopped at db_enter+0x8: nop TID PID UID PRFLAGS PFLAGS CPU COMMAND 57488 1522 0 0x11 0 1 perl 435923 9891 55 0x1000002 0 4 cc1plus 135860 36368 55 0x1000002 0 13 cc1plus 333743 96489 55 0x1000002 0 0 cc1plus 433162 55422 55 0x1000002 0 9 cc1plus 171658 49723 55 0x1000002 0 5 cc1plus 47127 57536 55 0x1000002 0 10 cc1plus 56600 9350 55 0x1000002 0 14 cc1plus 159792 13842 55 0x1000002 0 6 cc1plus 510019 10312 55 0x1000002 0 8 cc1plus 20489 65709 55 0x1000002 0 15 cc1plus 337455 42430 55 0x1000002 0 12 cc1plus 401407 80906 55 0x1000002 0 11 cc1plus 22993 62317 55 0x1000002 0 2 cc1plus 114916 17058 55 0x1000002 0 7 cc1plus *435412 33034 0 0x14000 0x200 3K pagedaemon trap(400fe6b19b0, 34, 1012f68, 820006, 3, 42) at trap+0x334 Lslowtrap_reenter(40015a58a00, 77b5db2000, deadbeefdeadc0c7, 1d8, 2df0fc468, 468) at Lslowtrap_reenter+0xf8 pmap_page_protect(40010716ab8, c16, 1cc9860, 193dfa0, 1cc9000, 1cc9000) at pmap_page_protect+0x1fc uvm_pagedeactivate(40010716a50, 40015a50d24, 18667a0, 0, 0, 1c8dac0) at uvm_pagedeactivate+0x54 uvmpd_scan_active(0, 0, 270f2, 18667a0, 0, ffffffffffffffff) at uvmpd_scan_active+0x150 uvm_pageout(400fe6b1e08, 55555556, 18667a0, 1c83f08, 1c83000, 1c8dc18) at uvm_pageout+0x2dc proc_trampoline(0, 0, 0, 0, 0, 0) at proc_trampoline+0x10 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{3}> ddb{3}> ddb{3}> ps /o TID PID UID PRFLAGS PFLAGS CPU COMMAND 57488 1522 0 0x11 0 1 perl 435923 9891 55 0x1000002 0 4 cc1plus 135860 36368 55 0x1000002 0 13 cc1plus 333743 96489 55 0x1000002 0 0 cc1plus 433162 55422 55 0x1000002 0 9 cc1plus 171658 49723 55 0x1000002 0 5 cc1plus 47127 57536 55 0x1000002 0 10 cc1plus 56600 9350 55 0x1000002 0 14 cc1plus 159792 13842 55 0x1000002 0 6 cc1plus 510019 10312 55 0x1000002 0 8 cc1plus 20489 65709 55 0x1000002 0 15 cc1plus 337455 42430 55 0x1000002 0 12 cc1plus 401407 80906 55 0x1000002 0 11 cc1plus 22993 62317 55 0x1000002 0 2 cc1plus 114916 17058 55 0x1000002 0 7 cc1plus *435412 33034 0 0x14000 0x200 3K pagedaemon ddb{3}> show proc PROC (pagedaemon) tid=435412 pid=33034 tcnt=1 stat=onproc flags process=14000 proc=200 runpri=4, usrpri=50, slppri=4, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0x40015a50fc0,0x40015a50a90 process=0x403c1f0ac70 user=0x400fe6ae000, vmspace=0x1c8e2c0 estcpu=0, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{3}> show uvm Current UVM status: pagesize=8192 (0x2000), pagemask=0x1fff, pageshift=13 2057215 VM pages: 1446170 active, 104107 inactive, 1 wired, 91303 free (91303 zero) freemin=68573, free-target=91430, inactive-target=516759, wired-max=685738 faults=-1646139234, traps=-1346997425, intrs=709572514, ctxswitch=368458634 fpuswitch=7786655 softint=86318616, syscalls=-1689153682, kmapent=12 fault counts: noram=0, noanon=0, noamap=0, pgwait=0, pgrele=0 relocks=6994201(335164), upgrades=1050667241(9720) anget(retries)=1162622063(0), amapcopy=302352908 neighbor anon/obj pg=403857156/660172689, gets(lock/unlock)=442541030/7329374 cases: anon=884461767, anoncow=278160296, obj=382612954, prcopy=59590377, przero=1044001823 daemon and swap counts: woke=153, revs=153, scans=0, obscans=0, anscans=0 busy=0, freed=0, reactivate=0, deactivate=411398 pageouts=0, pending=0, nswget=0 nswapdev=1 swpages=2130619, swpginuse=0, swpgonly=0 paging=0 kernel pointers: objs(kern)=0x1c2d7a0 -- jca