Re: kern/60522: evbppc/RB800 hits MI pmap KASSERT failure

The following reply was made to PR kern/60522; it has been noted by GNATS.

From: Nick Hudson <[email protected]>
To: [email protected],
 [email protected],
 [email protected],
 [email protected]
Cc: 
Subject: Re: kern/60522: evbppc/RB800 hits MI pmap KASSERT failure
Date: Sat, 1 Aug 2026 13:42:54 +0100

 On 01/08/2026 04:55, [email protected] via gnats wrote:
 >> Number:         60522
 >> Category:       kern
 >> Synopsis:       evbppc/RB800 hits MI pmap KASSERT failure
 >> Confidential:   no
 >> Severity:       serious
 >> Priority:       medium
 >> Responsible:    kern-bug-people
 >> State:          open
 >> Class:          sw-bug
 >> Submitter-Id:   net
 >> Arrival-Date:   Sat Aug 01 03:55:00 +0000 2026
 >> Originator:     Rin Okuyama
 >> Release:        11.9.7
 >> Organization:
 > Internet Initiative Japan Inc.
 >> Environment:
 > NetBSD rb800.local 11.99.7 NetBSD 11.99.7 (RB800-$Revision: 1.41 $) =
 #9: Sat Aug  1 11:40:53 JST 2026  =
 [email protected]:/home/rin/src/sys/arch/evbppc/compile/RB800 evbppc
 >> Description:
 > On RB800 with option INSECURE enabled, a KASSERT in MI pmap fires:
 > ```
 > # cd /usr/tests/dev/fss && atf-run
 > (snip)
 > tp-start: 1785555213.589886, t_fss, 1
 > tc-start: 1785555213.589970, basic
 > [ 136.6130204] panic: kernel diagnostic assertion =
 "!VM_PAGEMD_PVLIST_EMPTY_P(mdpg)" failed: file =
 "../../../../uvm/pmap/pmap.c", line 1330
 > [ 136.6348717] cpu0: Begin traceback...
 > [ 136.6348717] 0x00d3e9d0: at vpanic+0x154
 > [ 136.6432136] 0x00d3ea00: at kern_assert+0x60
 > [ 136.6432136] 0x00d3ea40: at pmap_pte_protect+0x210
 > [ 136.6538985] 0x00d3ea70: at pmap_pte_process+0x68
 > [ 136.6538985] 0x00d3eaa0: at pmap_protect+0x70
 > [ 136.6638310] 0x00d3eac0: at uvm_map_protect+0x268
 > [ 136.6638310] 0x00d3eb10: at kobj_affix+0x1f4
 > [ 136.6737622] 0x00d3eb30: at module_do_load+0x4ec
 > [ 136.6737622] 0x00d3ebf0: at module_autoload+0x108
 > [ 136.6846379] 0x00d3ec10: at spec_open+0x354
 > [ 136.6846379] 0x00d3ec90: at VOP_OPEN+0x4c
 > [ 136.6938266] 0x00d3ecc0: at vn_open+0x188
 > [ 136.6938266] 0x00d3ede0: at do_open+0xac
 > [ 136.6938266] 0x00d3ee40: at do_sys_openat+0x9c
 > [ 136.7052636] 0x00d3ee80: at sys_open+0x2c
 > [ 136.7052636] 0x00d3eeb0: at syscall+0x110
 > [ 136.7151053] 0x00d3ef20: user SC trap #5 by 0xfdbf84ac: srr1=3D0x2d030=
 
 > [ 136.7242392]             r1=3D0xffff76d0 cr=3D0x20042242 xer=3D0 =
 ctr=3D0xfdbf84a4
 > [ 136.7242392] cpu0: End traceback...
 
 Is this a regression? If so can you bisect please
 
 Otherwise, please enable UVMHIST and dump pmaphist and pmapexechist =
 after the panic.