Description zhixin01 2025-03-04 14:56:51 UTC

[缺陷描述]：
xfstests ext4 文件系统，generic/645用例执行失败，idmapped-mounts.c: 6671: nested_userns - Success - failure: sys_mount_setattr

测试日志如下：
#./check generic/645
FSTYP         -- ext4
PLATFORM      -- Linux/aarch64 v43c07451 6.6.71-3_rc1.al8.aarch64 #1 SMP PREEMPT_DYNAMIC Fri Feb 21 11:47:20 CST 2025
MKFS_OPTIONS  -- -F /dev/nvme0n1p2
MOUNT_OPTIONS -- -o acl,user_xattr /dev/nvme0n1p2 /fs/nvme0n1p2

generic/645       [failed, exit status 1]- output mismatch (see /var/tmp/tone/run/xfstests/results//generic/645.out.bad)
    --- tests/generic/645.out   2025-03-04 13:43:34.973763492 +0800
    +++ /var/tmp/tone/run/xfstests/results//generic/645.out.bad 2025-03-04 14:15:15.878151097 +0800
    @@ -1,2 +1,4 @@
     QA output created by 645
     Silence is golden
    +idmapped-mounts.c: 6671: nested_userns - Success - failure: sys_mount_setattr
    +vfstest.c: 2418: run_test - Success - failure: test that nested user namespaces behave correctly when attached to idmapped mounts
    ...
    (Run 'diff -u /var/tmp/tone/run/xfstests/tests/generic/645.out /var/tmp/tone/run/xfstests/results//generic/645.out.bad'  to see the entire diff)
Ran: generic/645
Failures: generic/645
Failed 1 of 1 tests

[重现概率]：
必现

[重现环境]：
环境信息：倚天710机器
100.82.243.208

#uname -r
6.6.71-3_rc1.al8.aarch64

#cat /etc/os-release
NAME="Alibaba Cloud Linux"
VERSION="3 (Soaring Falcon)"
ID="alinux"
ID_LIKE="rhel fedora centos anolis"
VERSION_ID="3"
UPDATE_ID="10"
PLATFORM_ID="platform:al8"
PRETTY_NAME="Alibaba Cloud Linux 3 (Soaring Falcon)"
ANSI_COLOR="0;31"
HOME_URL="https://www.aliyun.com/"

#lscpu
Architecture:        aarch64
Byte Order:          Little Endian
CPU(s):              124
On-line CPU(s) list: 0-123
Thread(s) per core:  1
Core(s) per socket:  124
Socket(s):           1
NUMA node(s):        2
Vendor ID:           ARM
BIOS Vendor ID:      T-HEAD
Model:               0
Model name:          Neoverse-N2
BIOS Model name:     Yitian710-124
Stepping:            r0p0
CPU MHz:             2750.002
BogoMIPS:            100.00
Hypervisor vendor:   Alibaba
Virtualization type: full
L1d cache:           64K
L1i cache:           64K
L2 cache:            1024K
L3 cache:            65536K
NUMA node0 CPU(s):   0-61
NUMA node1 CPU(s):   62-123
Flags:               fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp cpuid asimdrdm jscvt fcma lrcpc dcpop sha3 sm3 sm4 asimddp sha512 sve asimdfhm dit uscat ilrcpc flagm sb dcpodp sve2 sveaes svepmull svebitperm svesha3 svesm4 flagm2 frint svei8mm svebf16 i8mm bf16 dgh

#free -h
              total        used        free      shared  buff/cache   available
Mem:          251Gi       5.7Gi       243Gi       9.0Mi       4.0Gi       245Gi
Swap:         2.0Gi       116Mi       1.9Gi

#cat /proc/cmdline
BOOT_IMAGE=(hd0,gpt2)/boot/vmlinuz-6.6.71-3_rc1.al8.aarch64 root=UUID=5d4c9cac-5324-464b-8971-09deff261ae7 ro biosdevname=0 rd.driver.pre=ahci iommu.passthrough=1 iommu.strict=0 nospectre_bhb ssbd=force-off systemd.unified_cgroup_hierarchy=0 cgroup.memory=nokmem console=ttyS0,115200 fsck.repair=yes crashkernel=0M-2G:0M,2G-256G:256M,256G-1024G:320M,1024G-:384M

[重现步骤]：
# 下载并编译测试套
git clone http://gitlab-sp.alibaba-inc.com/AKTF/xfstests-dev.git -b kernel_6.6
cd xfstests-dev
make

# 测试准备
mkfs.ext4 /dev/nvme0n1p1
mkfs.ext4 /dev/nvme0n1p2
export FSTYP=ext4
export TEST_DEV=/dev/nvme0n1p1
export SCRATCH_DEV=/dev/nvme0n1p2
export TEST_DIR=/fs/nvme0n1p1
export SCRATCH_MNT=/fs/nvme0n1p2

# 执行测试
./check generic/645

[期望结果]：
用例执行PASS

[实际结果]：
用例执行Fail

[分析]
1. 取上游最新代码测试，用例也是fail的（https://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git）
#./check generic/645
FSTYP         -- ext4
PLATFORM      -- Linux/aarch64 v43c07451 6.6.71-3_rc1.al8.aarch64 #1 SMP PREEMPT_DYNAMIC Fri Feb 21 11:47:20 CST 2025
MKFS_OPTIONS  -- -F /dev/nvme0n1p2
MOUNT_OPTIONS -- -o acl,user_xattr /dev/nvme0n1p2 /fs/nvme0n1p2

generic/645       [failed, exit status 1]- output mismatch (see /root/xfstests-dev/results//generic/645.out.bad)
    --- tests/generic/645.out   2025-03-04 14:05:30.611593806 +0800
    +++ /root/xfstests-dev/results//generic/645.out.bad 2025-03-04 14:55:15.615015585 +0800
    @@ -1,2 +1,4 @@
     QA output created by 645
     Silence is golden
    +idmapped-mounts.c: 6671: nested_userns - Success - failure: sys_mount_setattr
    +vfstest.c: 2418: run_test - Success - failure: test that nested user namespaces behave correctly when attached to idmapped mounts
    ...
    (Run 'diff -u /root/xfstests-dev/tests/generic/645.out /root/xfstests-dev/results//generic/645.out.bad'  to see the entire diff)

This test wants kernel fix:
      dacfd001eaf2 fs/mnt_idmapping.c: Return -EINVAL when no map is written

Ran: generic/645
Failures: generic/645
Failed 1 of 1 tests

以上请参考