Bug 986339

Summary: starting systemd-binfmt.service on arm makes any exec fail on too many levels of symlinks
Product: [Fedora] Fedora Reporter: Pavel Holica <pholica>
Component: qemuAssignee: Fedora Virtualization Maintainers <virt-maint>
Status: CLOSED DUPLICATE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: urgent Docs Contact:
Priority: high    
Version: 19CC: amit.shah, berrange, cfergeau, dwmw2, harrisbritt6904.0, itamar, johannbg, lnykryn, mschmidt, msekleta, notting, pbonzini, plautrba, rjones, scottt.tw, systemd-maint, virt-maint, vpavlin, zbyszek
Target Milestone: ---   
Target Release: ---   
Hardware: arm   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2013-07-19 13:21:56 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:

Description Pavel Holica 2013-07-19 13:06:26 UTC 
Description of problem:
I've installed Fedora 19 with default package set on calxeda system and in hangs during boot. After deep investigation, I've found, that this is caused by starting systemd-binfmt.service. After this service is started, any exec fail on too many levels of symlinks. It can be easily manually reproduced.

Version-Release number of selected component (if applicable):
systemd-204-9.fc19.armv7hl

How reproducible:
always

Steps to Reproduce:
1. Perform minimal installation
2. Install qemu-user package
3. run: systemctl start systemd-binfmt.service
4. bash

Actual results:
# systemctl start systemd-binfmt.service
# bash
-bash: /bin/bash: Too many levels of symbolic links

Expected results:
Bash is started

Additional info:
Comment 1 Michal Schmidt 2013-07-19 13:08:24 UTC 
What are the contents of config files in the following directories?:

/etc/binfmt.d/
/run/binfmt.d/
/usr/lib/binfmt.d/
Comment 2 Pavel Holica 2013-07-19 13:13:58 UTC 
Those files are from qemu-user-1.4.2-3.fc19.armv7h package

# find /etc/binfmt.d/
/etc/binfmt.d/

# find /run/binfmt.d/
find: ‘/run/binfmt.d/’: No such file or directory

# find /usr/lib/binfmt.d/
/usr/lib/binfmt.d/
/usr/lib/binfmt.d/qemu-sh4.conf
/usr/lib/binfmt.d/qemu-arm.conf
/usr/lib/binfmt.d/qemu-microblaze.conf
/usr/lib/binfmt.d/qemu-cris.conf
/usr/lib/binfmt.d/qemu-ppc64.conf
/usr/lib/binfmt.d/qemu-mips64.conf
/usr/lib/binfmt.d/qemu-sparc32plus.conf
/usr/lib/binfmt.d/qemu-ppc64abi32.conf
/usr/lib/binfmt.d/qemu-sparc.conf
/usr/lib/binfmt.d/qemu-sh4eb.conf
/usr/lib/binfmt.d/qemu-mips.conf
/usr/lib/binfmt.d/qemu-microblazeel.conf
/usr/lib/binfmt.d/qemu-s390x.conf
/usr/lib/binfmt.d/qemu-alpha.conf
/usr/lib/binfmt.d/qemu-ppc.conf
/usr/lib/binfmt.d/qemu-i386.conf
/usr/lib/binfmt.d/qemu-mipsel.conf
/usr/lib/binfmt.d/qemu-m68k.conf
/usr/lib/binfmt.d/qemu-sparc64.conf
/usr/lib/binfmt.d/qemu-armeb.conf
/usr/lib/binfmt.d/qemu-mips64el.conf
Comment 3 Michal Schmidt 2013-07-19 13:16:54 UTC 
(In reply to Pavel Holica from comment #2)
> /usr/lib/binfmt.d/qemu-arm.conf

I suspect this tells the kernel to run ARM binaries through the QEMU emulator, which itself is an ARM binary, so it runs in the QEMU emulator, which itself ...
Comment 4 David Woodhouse 2013-07-19 13:21:56 UTC 

*** This bug has been marked as a duplicate of bug 974804 ***
Comment 5 Pavel Holica 2013-07-19 13:26:14 UTC 
Wow, you're right.

I've just did:
# mv /usr/lib/binfmt.d/qemu-arm* /root/
# systemctl unmask systemd-binfmt.service
# systemctl start systemd-binfmt.service
# bash

and it worked.
Comment 6 Richard W.M. Jones 2013-07-19 13:29:36 UTC 
You should actually check if updating to qemu-1.4.2-4.fc19
fixes this, since this was fixed between -3 and -4.
Comment 7 Pavel Holica 2013-07-19 13:31:24 UTC 
Thank you. I realized this at the moment I posted the comment and looked on bug 974804.
Comment 8 harrisbritt6904.0 2020-04-25 19:07:10 UTC Comment hidden (spam)