Subject: port-alpha/29556: pmap_emulate_reference: write but not FOW
To: None <port-alpha-maintainer@netbsd.org, gnats-admin@netbsd.org,>
From: None <yamt@mwd.biglobe.ne.jp>
List: netbsd-bugs
Date: 02/28/2005 07:22:01
>Number: 29556
>Category: port-alpha
>Synopsis: pmap_emulate_reference: write but not FOW
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: port-alpha-maintainer
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Mon Feb 28 07:22:01 +0000 2005
>Originator: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
>Release: NetBSD 2.99.14
>Organization:
>Environment:
System: NetBSD kaeru 2.99.14
Architecture: alpha
Machine: alpha
>Description:
i occasionally see the following panics on my box.
before i enabled the debug check (pmap.c rev.1.208),
it used to be infinite traps, which can be recovered by
"ALPHA_TBIA(); alpha_pal_imb();" equivalent from ddb.
so i guess it's due to stale tlbs or something like that.
panic: pmap_emulate_reference: write but not FOW
Stopped in pid 7723.1 (cc1plus) at netbsd:cpu_Debugger+0x4: ret zero,(ra)
db> bt
cpu_Debugger() at netbsd:cpu_Debugger+0x4
panic() at netbsd:panic+0x1f8
pmap_emulate_reference() at netbsd:pmap_emulate_reference+0x18c
trap() at netbsd:trap+0x58c
XentMM() at netbsd:XentMM+0x20
--- memory management fault (from ipl 0) ---
--- user mode ---
>How-To-Repeat:
>Fix: