Bug 1281446

Summary: FTPBS: FATAL: modpost: Section mismatches detected.
Product: [Fedora] Fedora Reporter: Karsten Hopp <karsten>
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED RAWHIDE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: medium    
Version: rawhideCC: dan, gansalmon, hannsj_uhl, itamar, jonathan, kernel-maint, labbott, madhu.chinakonda, mchehab, nickc
Target Milestone: ---   
Target Release: ---   
Hardware: ppc64le   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-11-16 18:31:23 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1071880    

Description Karsten Hopp 2015-11-12 14:44:03 UTC
Description of problem:
the latest 4.4 kernels won't build anymore on ppc64le:

+ make -f ./scripts/Makefile.modpost vmlinux.o
WARNING: modpost: Found 4 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
FATAL: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.



With CONFIG_SECTION_MISMATCH_WARN_ONLY=y :
+ make -f ./scripts/Makefile.modpost vmlinux.o
WARNING: vmlinux.o(.text+0x8994): Section mismatch in reference from the variable __boot_from_prom to the function .init.text:prom_init()
The function __boot_from_prom() references
the function __init prom_init().
This is often because __boot_from_prom lacks a __init 
annotation or the annotation of prom_init is wrong.

WARNING: vmlinux.o(.text+0x8c30): Section mismatch in reference from the variable start_here_multiplatform to the function .init.text:early_setup()
The function start_here_multiplatform() references
the function __init early_setup().
This is often because start_here_multiplatform lacks a __init 
annotation or the annotation of early_setup is wrong.

WARNING: vmlinux.o(.text+0x8c54): Section mismatch in reference from the variable start_here_common to the function .init.text:setup_system()
The function start_here_common() references
the function __init setup_system().
This is often because start_here_common lacks a __init 
annotation or the annotation of setup_system is wrong.

WARNING: vmlinux.o(.text+0x8c68): Section mismatch in reference from the variable start_here_common to the function .init.text:start_kernel()
The function start_here_common() references
the function __init start_kernel().
This is often because start_here_common lacks a __init 
annotation or the annotation of start_kernel is wrong.

FATAL: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.
scripts/Makefile.modpost:97: recipe for target 'vmlinux.o' failed



Version-Release number of selected component (if applicable):
kernel-4.4.0-0.rc0.git6.1.fc24
kernel-4.4.0-0.rc0.git7.2.fc24

How reproducible:
always

Steps to Reproduce:
1. ppc-kernel build --scratch --arch-override ppc64le f24 kernel-4.4.0-0.rc0.git6.1.fc24.src.rpm
2.
3.

Actual results:
http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=2896128
http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=2898203


Additional info:
This issue is on ppc64le only, ppc64 and ppc64p7 build just fine.

Comment 1 Dan HorĂ¡k 2015-11-12 15:00:39 UTC
Might be the same issue that caused the troubles to build emacs in RHEL with latest binutils. It was also something related to ELF section ordering (bug 1223033).

Comment 2 Karsten Hopp 2015-11-12 16:30:24 UTC
The same error occurs on a fully updated F22 ppc64le machine with binutils-2.25-9.fc22.ppc64le and elfutils-0.163-4.fc22.ppc64le

Comment 3 Laura Abbott 2015-11-12 17:48:39 UTC
I think the section mismatch errors were always there but I accidentally turned on an option which makes them fatal. I've switched the Kconfig and this should be fixed in tonight's rawhide.

Comment 4 Laura Abbott 2015-11-16 18:31:23 UTC
Corrected the Kconfig. Should be in rawhide right now.