[linux-lvm] Trouble Booting Custom Kernel with QEMU: dracut-initqueue timeout waiting for /dev/sysvg/root

Hi All,

I hope this email finds you well. I am currently facing an issue with
booting a VM using a custom-compiled kernel and would appreciate your
expertise on the matter.

### Problem Description
I have downloaded the `Fedora-Server-KVM-38-1.6.x86_64.qcow2` image and
successfully booted it using `qemu-system-x86_64`. However, when I try
to boot this VM with a custom-compiled kernel using the `-kernel` flag,
it fails to boot. The root filesystem is on LVM, and it seems the kernel
needs to activate volume groups before mounting the root filesystem.

### Steps Taken
1. Copied `/boot/config-*` from inside the VM and used it to build the
kernel on the host machine.
2. Also tried `make localmodconfig` after copying `/boot/config-*`.
3. Built `initrd.img` using `dracut`.

#### Dracut Command
```bash
dracut initrd.img --kmoddir $INSTALL_MOD_PATH/lib/modules/6.4.0+ 6.4.0+
```

#### Qemu Command
```bash
qemu-system-x86_64 -enable-kvm -nographic -vga none -smp 1 -m 2G \
-kernel arch/x86_64/boot/bzImage -initrd initrd.img -append
"root=/dev/vda3 ro console=ttyS0" \
-device virtio-blk-pci,drive=rootdisk -drive
file=Fedora-Server-KVM-38-1.6.x86_64.qcow2,if=none,cache=none,id=rootdisk,format=qcow2
\
-net nic,model=virtio -net user,hostfwd=tcp::5555-:22
```

### Error Observed
The kernel panics with the following message:
```
[    0.843818] List of all partitions:
[    0.844084] fd00         7340032 vda
[    0.844086]  driver: virtio_blk
[    0.844571]   fd01            1024 vda1
f3137bf4-2cf0-4ef6-98a9-dda32e23ddcd
[    0.844573]
[    0.845269]   fd02         1048576 vda2
3030ca3b-6606-4a8e-a5ee-efdc7858fb64
[    0.845270]
[    0.845976]   fd03         6288384 vda3
416b3009-59d3-4ed1-b126-3cb216aa02f4
[    0.845976]
[    0.846593] fd10        20971520 vdb
[    0.846594]  driver: virtio_blk
[    0.847091] 0b00         1048575 sr0
[    0.847092]  driver: sr
[    0.847545] No filesystem could mount root, tried:
[    0.847546]  ext3
[    0.847906]  ext2
[    0.848060]  ext4
[    0.848220]  fuseblk
[    0.848362]  xfs
[    0.848537]  btrfs
[    0.848674]
[    0.848951] Kernel panic - not syncing: VFS: Unable to mount root fs
on unknown-block(253,3)
[    0.849574] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.4.0+ #3
[    0.850012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.o4
[    0.850837] Call Trace:
[    0.851109]  <TASK>
[    0.851261]  dump_stack_lvl+0x47/0x60
[    0.851524]  panic+0x178/0x330
[    0.851745]  mount_block_root+0x278/0x280
[    0.852030]  ? __pfx_ignore_unknown_bootoption+0x10/0x10
[    0.852403]  prepare_namespace+0x156/0x180
[    0.852705]  kernel_init_freeable+0x416/0x460
[    0.853031]  ? __pfx_kernel_init+0x10/0x10
[    0.853328]  kernel_init+0x1a/0x140
[    0.853585]  ret_from_fork+0x2c/0x50
[    0.853858]  </TASK>
[    0.854067] Kernel Offset: 0x16000000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfff)
[    0.854866] ---[ end Kernel panic - not syncing: VFS: Unable to mount
root fs on unknown-block(253,3) ]---
```

### Additional Information
- `/etc/fstab` and `lsblk` output are attached for reference.

#### /etc/fstab
```
/dev/mapper/sysvg-root  /                       xfs     defaults        0 0
UUID=2cd18fbf-7705-4a86-8bb8-c18dafdee822 /boot                   ext4
 defaults        1 2
```

#### lsblk
```
NAME           MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
sr0             11:0    1 1024M  0 rom
zram0          251:0    0  3.8G  0 disk [SWAP]
vda            252:0    0    7G  0 disk
├─vda1         252:1    0    1M  0 part
├─vda2         252:2    0    1G  0 part /boot
└─vda3         252:3    0    6G  0 part
  └─sysvg-root 253:0    0    6G  0 lvm  /
```

#### lsinitrd initrd.img
```
Image: initrd.img: 49M
========================================================================
Version: dracut-049-223.git20230119.el8

Arguments: --force --kmoddir '$INSTALL_MOD_PATH/lib/modules/6.4.0+ 6.4.0+'

dracut modules:
bash
systemd
systemd-initrd
nss-softokn
i18n
network-manager
network
ifcfg
drm
plymouth
prefixdevname
crypt
dm
kernel-modules
kernel-modules-extra
kernel-network-modules
lvm
resume
rootfs-block
terminfo
udev-rules
biosdevname
dracut-systemd
usrmount
base
fs-lib
memstrack
microcode_ctl-fw_dir_override
shutdown
```

I would be grateful for any guidance or suggestions you could provide to
resolve this issue.


vishal.c

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