Re: [QUERY] Building and testing Aarch64

From: Ramkumar Ramachandra
Date: Sat Sep 28 2013 - 05:40:29 EST

Andreas Schwab wrote:
> Ramkumar Ramachandra <artagnon@xxxxxxxxx> writes:
>> Is there a bug in the Kconfig dependency tree? Sounds like VIRTIO_MMIO
>> requires some vga (?) drivers to be compiled in as well.

I hit this bug when I do `make menuconfig` directly (which
configuration does it start out with?). When I `make defconfig`
(picking up arch/arm64/configs/defconfig), and then enable VIRTIO_MMIO
in the menuconfig, it builds fine.

> I don't have any VGA option enabled. You should use a serial console

arch/arm64/configs/defconfig:676 already builds this feature in.

Unfortunately, even with VIRTIO_MMIO built in, I get the same error:

VFS: Cannot open root device "vda" or unknown-block(0,0): error -6
Please append a correct "root=" boot option; here are the available
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

Any hints on how to proceed from here? What is your kernel
configuration (are you using arch/arm64/configs/defconfig)? Is
root=/dev/vda part of your kernel arguments?

How is this supposed to work? When I pass the rootfs-file as the
--block-device, it's supposed to see the file as the block device
/dev/vda (what determines this?), mount it, and finally get devtmpfs
to populate the /dev, right? The transcript from the working
linux-system.axf (with raring-rootfs) looks like:

[ 4.977788] vda: unknown partition table
[ 4.997392] mtdoops: mtd device (mtddev=name/number) must be supplied
[ 5.001787] smc91x: not found (-19).
[ 5.011141] mousedev: PS/2 mouse device common for all mice
[ 5.020830] device-mapper: ioctl: 4.23.1-ioctl (2012-12-18)
initialised: dm-devel@xxxxxxxxxx
[ 5.027396] TCP: cubic registered
[ 5.027456] Initializing XFRM netlink socket
[ 5.027885] NET: Registered protocol family 17
[ 5.028207] NET: Registered protocol family 15
[ 5.047665] EXT3-fs (vda): error: couldn't mount because of
unsupported optional features (240)
[ 5.050214] EXT2-fs (vda): error: couldn't mount because of
unsupported optional features (244)
[ 5.095085] EXT4-fs (vda): recovery complete
[ 5.096307] EXT4-fs (vda): mounted filesystem with ordered data
mode. Opts: (null)
[ 5.096723] VFS: Mounted root (ext4 filesystem) on device 254:0.
[ 5.098965] devtmpfs: mounted

What am I missing?
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