Re: kern/54874: "modload exec_aout" fails due to missing dependencies

[Paul Goyette <paul%whooppee.com@localhost>]

The following reply was made to PR kern/54874; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/54874: "modload exec_aout" fails due to missing dependencies
Date: Sat, 18 Jan 2020 13:42:40 -0800 (PST)

 This would seem to be a pre-existing (prior to netbsd-9) bug, and not
 a recently-introduced regression.
 
 Can you try to build a MODULAR kernel from netbsd-8 branch to confirm?
 
 The coredump code had a major re-org in -current (after the netbsd-9
 branch was cut).  Unfortunately, the changes were fairly intrusive, and
 would introduce kernel ABI changes that should not be permitted on the
 branch.
 
 As an alternative, you could add ``modular'' to the list of attributes
 in files.kern which should include the required routine in all modular
 kernels.  Please try this and let me know if it works for you.  (We
 should be able to include this change in the netbsd-9 branch.)
 
 Index: files.kern
 ===================================================================
 RCS file: /cvsroot/src/sys/kern/files.kern,v
 retrieving revision 1.34
 diff -u -p -r1.34 files.kern
 --- files.kern	4 Apr 2019 20:19:07 -0000	1.34
 +++ files.kern	18 Jan 2020 21:40:40 -0000
 @@ -16,7 +16,8 @@ file	kern/bufq_readprio.c		bufq_readprio
   file	kern/compat_stub.c		kern
   file	kern/core_elf32.c		exec_elf32
   file	kern/core_elf64.c		exec_elf64
 -file	kern/core_netbsd.c		exec_aout | exec_coff | exec_ecoff
 +file	kern/core_netbsd.c		exec_aout | exec_coff | exec_ecoff |
 +					modular
   file	kern/cnmagic.c			kern
   file	kern/exec_aout.c		exec_aout
   file	kern/exec_ecoff.c		exec_ecoff
 
 
 
 On Sat, 18 Jan 2020, Izumi Tsutsui wrote:
 
 >> Number:         54874
 >> Category:       kern
 >> Synopsis:       "modload exec_aout" fails due to missing dependencies
 >> Confidential:   no
 >> Severity:       non-critical
 >> Priority:       medium
 >> Responsible:    kern-bug-people
 >> State:          open
 >> Class:          sw-bug
 >> Submitter-Id:   net
 >> Arrival-Date:   Sat Jan 18 21:05:00 +0000 2020
 >> Originator:     Izumi Tsutsui
 >> Release:        NetBSD 9.0_RC1
 >> Organization:
 >> Environment:
 > System: etBSD  9.0_RC1 NetBSD 9.0_RC1 (MODULAR) #2: Sun Jan 19 04:54:01 JST 2020  tsutsui@mirage:/s/netbsd-9/src/sys/arch/sun3/compile/MODULAR sun3
 > Architecture: m68k
 > Machine: sun3
 >> Description:
 > On NetBSD/sun3 9.0_RC1 (options EXEC_AOUT is disabled by default)
 > "modload exec_aout" fails:
 > ---
 > modload exec_aout
 > [ 1994.0000220] kobj_checksyms, 988: [exec_aout]: linker error: symbol `coredump_netbsd' not found
 > [ 1994.0200220] WARNING: module error: unable to affix module `exec_aout', error 8
 > modload: exec_aout: Exec format error
 > ---
 >
 > The missing coredump_netbsd() is in sys/kern/coredump_netbsd.c.
 >
 > However it isn't configured unless options EXEC_AOUT (or EXEC_ECOFF etc.)
 > are defined, per sys/kern/files.kern:
 > ---
 > file	kern/core_elf32.c		exec_elf32
 > file	kern/core_elf64.c		exec_elf64
 > file	kern/core_netbsd.c		exec_aout | exec_coff | exec_ecoff
 > ---
 >
 > sys/module/exec_aout/Makefile only pulls exec_aout.c so
 > coredump_netbsd() is not resolved.
 >
 >> How-To-Repeat:
 > - build NetBSD/sun3 kernel with options MODULAR
 >  (or build kernel without EXEC_AOUT)
 > - modload exec_aout on single user
 >
 >> Fix:
 > No idea.  Prepare proper dependencies in core_netbsd.c for module?
 >
 > ---
 > Izumi Tsutsui
 >
 >
 > !DSPAM:5e237340296238931812264!
 >
 >
 
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