Re: [Qemu-devel] [V9fs-developer] QEMU dies on any attempt to load a Linux kernel module when using a 9P rootfs

[Dominique Martinet <dominique.martinet@cea.fr>]

Hi,

Christopher Covington wrote on Thu, Aug 21, 2014 at 03:50:58PM -0400:
> With my 3.15.0+ kernel, qemu-system-x86_64 substituted for qemu-kvm, and the
> path changed from your arguments I get:
> 
> 9pnet_virtio: no channels available
> VFS: Cannot open root device "root" or unknown-block(0,0): error -2
> Please append a correct "root=" boot option; here are the available partitions:
> 0b00         1048575 sr0  driver: sr
> Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014

I'm pretty sure that's the same problem that's been reported a few times
here, could you try again after cherry-picking this commit:

commit f15844e0777fec936f87a87f97394f83911dacd3
Author: Dominique Martinet <dominique.martinet@cea.fr>
Date:   Wed May 21 10:02:12 2014 +0200

    9P: fix return value in v9fs_fid_xattr_set
    
    v9fs_fid_xattr_set is supposed to return 0 on success.
    
    This corrects the behaviour introduced in commit
    bdd5c28dcb8330b9074404cc92a0b83aae5606a
    "9p: fix return value in case in v9fs_fid_xattr_set()"
    
    (The function returns a negative error on error, as expected)
    
    Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
    Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>


It has gotten in in v3.16-rc1, so your 3.15.0+ proably doesn't have it.

Cheers,
-- 
Dominique