OverlayFS throws `EOPNOTSUPP` for `listxattr` until copy-up is performed

[Johan-Liebert1]

Ran into this issue while debugging bootc-dev/bootc#2190 (comment)

[root@localhost ~]# uname -a
Linux localhost.localdomain 6.12.0-236.el10.x86_64 #1 SMP PREEMPT_DYNAMIC Wed Jun  3 12:31:11 UTC 2026 x86_64 GNU/Linux

The issue I'm seeing

bash-5.2# getfattr -d /var
getfattr: /var: Operation not supported
bash-5.2# touch /var/.x
bash-5.2# getfattr -d /var
bash-5.2# 

Output from strace BEFORE writing to a directory

bash-5.2# ./strace getfattr -d /usr
execve("/usr/bin/getfattr", ["getfattr", "-d", "/usr"], 0x7fff3b0e8520 /* 9 vars */) = 0
[...]
prlimit64(0, RLIMIT_NOFILE, NULL, {rlim_cur=1024*1024, rlim_max=1024*1024}) = 0
newfstatat(AT_FDCWD, "/usr", {st_mode=S_IFDIR|0755, st_size=4096, ...}, AT_SYMLINK_NOFOLLOW) = 0
listxattr("/usr", NULL, 0)              = -1 EOPNOTSUPP (Operation not supported)
write(2, "getfattr: /usr: Operation not su"..., 40getfattr: /usr: Operation not supported
) = 40
exit_group(1)                           = ?
+++ exited with 1 +++

This is on a CentOS 10 image

bash-5.2# cat /etc/os-release 
NAME="CentOS Stream"
VERSION="10 (Coughlan)"
RELEASE_TYPE=stable
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="10"
PLATFORM_ID="platform:el10"
PRETTY_NAME="CentOS Stream 10 (Coughlan)"
ANSI_COLOR="0;31"
LOGO="fedora-logo-icon"
CPE_NAME="cpe:/o:centos:centos:10"
HOME_URL="https://centos.org/"
VENDOR_NAME="CentOS"
VENDOR_URL="https://centos.org/"
BUG_REPORT_URL="https://issues.redhat.com/"
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux 10"
REDHAT_SUPPORT_PRODUCT_VERSION="CentOS Stream"

[Johan-Liebert1]

It was introduced by me with this commit bootc-dev/bootc@4e287c1

[Johan-Liebert1]

Reopening because it's happening even after removing the commit https://github.com/bootc-dev/bootc/actions/runs/27129962745/job/80072492524

[Johan-Liebert1]

This was happening because for tests that want an update image, BOOTC_upgrade_image env var was not set, so it was creating a new UKI image using the RO image from host storage