Re: kern/51436: tmpfs mount crashes when tmpfs is autoloaded as a module

[Martin Husemann <martin%duskware.de@localhost>]

The following reply was made to PR kern/51436; it has been noted by GNATS.

From: Martin Husemann <martin%duskware.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/51436: tmpfs mount crashes when tmpfs is autoloaded as a module
Date: Mon, 22 Aug 2016 23:30:42 +0200

 With some hints from Jürgen I added more printfs and now end up with this
 failure mode:
 
 # mount /var/shm
 tmpfs_mem_info: size: 0 uvmexp.wired: 0
 tmpfs_mem_info: returning 0
 tmpfs_node_get: nodes 0 max 2097155
 tmpfs_mem_info: size: 0 uvmexp.wired: 0
 tmpfs_mem_info: returning 0
 tmpfs_bytes_max: avail 0 limit 2147483648
 tmpfs_bytes_max: returning 0
 tmpfs_mem_incr failed, returning NULL
 error from VFS_NEWVNODE: 28
 panic: vcache_new for tmpfs root failed: 28
 Stopped in pid 68.1 (mount_tmpfs) at    netbsd:cpu_Debugger+0x4:        nop
 db{0}> show uvm
 Current UVM status:
   pagesize=8192 (0x2000), pagemask=0x1fff, pageshift=13
 , ncolors=32  1031154 VM pages: 707 active, 0 inactive, 0 wired, 1021192 free
   pages  249 anon, 170 file, 288 exec
   freemin=256, free-target=341, wired-max=343718
   cpu0:
     faults=6270, traps=3592, intrs=103023, ctxswitch=11936
     softint=24018, syscalls=3731
   cpu1:
     faults=3752, traps=2187, intrs=81425, ctxswitch=4067
     softint=3633, syscalls=4735
   fault counts:
     noram=0, noanon=0, pgwait=0, pgrele=0
     ok relocks(total)=189(189), anget(retrys)=1100(0), amapcopy=692
     neighbor anon/obj pg=1121/7364, gets(lock/unlock)=2639/189
     cases: anon=666, anoncow=434, obj=1938, prcopy=701, przero=1194
   daemon and swap counts:
     woke=0, revs=0, scans=0, obscans=0, anscans=0
     busy=0, freed=0, reactivate=0, deactivate=0
     pageouts=0, pending=0, nswget=0
     nswapdev=0, swpgavail=0
     swpages=0, swpginuse=0, swpgonly=0, paging=0
 
 
 The whole thing works on a machine with less memory installed.
 
 Martin