Re: kern/55237

[Yorick Hardy <yorickhardy%gmail.com@localhost>]

The following reply was made to PR kern/55237; it has been noted by GNATS.

From: Yorick Hardy <yorickhardy%gmail.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/55237
Date: Sun, 1 Nov 2020 22:49:18 +0200

 I have put a vprint just before the panic. I am not sure what has
 changed - the usecount and writecount are now both 1 - here are
 two examples. In both cases the inodes are reported as unallocated
 by fsdb (after reboot). I don't seem to find the time or expertise
 to examine the code on my own, are there any other diagnostics I
 could add to try and diagnose the problem?
 
 [ 53296.926965] vnode bad write count: vnode 0xffff87564dd44b80 flags 0x4c38<MAPPED,MPSAFE,LOCKSWORK,WRMAP,PAGES,ONWORKLST>
 [ 53296.926965]         tag VT_UFS(1) type VREG(1) mount 0xffff87542b686000 typedata 0x0
 [ 53296.926965]         usecount 1 writecount 1 holdcount 1
 [ 53296.926965]         size 30000 writesize 30000 numoutput 0
 [ 53296.926965]         data 0xffff8756501facd0 lock 0xffff87564dd44d40
 [ 53296.926965]         state LOADED key(0xffff87542b686000 8) ee 1b 87 00 00 00 00 00
 [ 53296.926965]         lrulisthd 0xffffffff8105b6d0
 [ 53296.926965]         tag VT_UFS, ino 8854510, on dev 0, 0 flags 0x0, nlink 1
 [ 53296.926965]         mode 0100600, owner 1000, group 0, size 196608
 [ 53296.926965] panic: vrelel: bad write count 1 (pending 0)
 [ 53296.926965] cpu0: Begin traceback...
 [ 53296.926965] vpanic() at netbsd:vpanic+0x156
 [ 53296.936965] vtryrele() at netbsd:vtryrele
 [ 53296.946962] vrelel() at netbsd:vrelel+0x318
 [ 53296.946962] uvm_unmap_detach() at netbsd:uvm_unmap_detach+0x68
 [ 53296.946962] uvm_unmap1() at netbsd:uvm_unmap1+0x4e
 [ 53296.956962] uvm_mremap() at netbsd:uvm_mremap+0x39a
 [ 53296.956962] sys_mremap() at netbsd:sys_mremap+0x67
 [ 53296.956962] syscall() at netbsd:syscall+0x1cc
 [ 53296.966961] --- syscall (number 411) ---
 [ 53296.966961] netbsd:syscall+0x1cc:
 [ 53296.966961] cpu0: End traceback...
 
 [ 30742.529952] vnode bad write count: vnode 0xffff84c0e53554c0 flags 0x4c38<MAPPED,MPSAFE,LOCKSWORK,WRMAP,PAGES,ONWORKLST>
 [ 30742.529952]         tag VT_UFS(1) type VREG(1) mount 0xffff84c04b68e000 typedata 0x0
 [ 30742.529952]         usecount 1 writecount 1 holdcount 1
 [ 30742.529952]         size c000 writesize c000 numoutput 0
 [ 30742.529952]         data 0xffff84c0dc50e778 lock 0xffff84c0e5355680
 [ 30742.529952]         state LOADED key(0xffff84c04b68e000 8) a9 1b 87 00 00 00 00 00
 [ 30742.529952]         lrulisthd 0xffffffff8105b6d0
 [ 30742.529952]         tag VT_UFS, ino 8854441, on dev 0, 0 flags 0x18, nlink 1
 [ 30742.529952]         mode 0100600, owner 1000, group 0, size 49152
 [ 30742.529952] panic: vrelel: bad write count 1 (pending 0)
 [ 30742.529952] cpu1: Begin traceback...
 [ 30742.529952] vpanic() at netbsd:vpanic+0x156
 [ 30742.539957] vtryrele() at netbsd:vtryrele
 [ 30742.539957] vrelel() at netbsd:vrelel+0x318
 [ 30742.549951] uvm_unmap_detach() at netbsd:uvm_unmap_detach+0x68
 [ 30742.549951] uvmspace_free() at netbsd:uvmspace_free+0xdc
 [ 30742.549951] exit1() at netbsd:exit1+0x188
 [ 30742.559948] sys_exit() at netbsd:sys_exit+0x39
 [ 30742.559948] syscall() at netbsd:syscall+0x1cc
 [ 30742.559948] --- syscall (number 1) ---
 [ 30742.559948] netbsd:syscall+0x1cc:
 [ 30742.559948] cpu1: End traceback...
 
 -- 
 Kind regards,
 
 Yorick Hardy