Re: [Qemu-devel] [Consult] nfs-vsocks support

[Liu, Jing2]

On 3/26/2018 6:12 PM, Liu, Jing2 wrote:
> Hi Stefan,
>
> Thank you very much for the response! It truly gave me much help.
>
> On 3/24/2018 12:02 AM, Stefan Hajnoczi wrote:
[...]
> > > Could you give me some help and thanks in advance!
> >
> > Here is a script that launches nfsd and runs a guest:
> > https://github.com/stefanha/linux/commit/38cbc15661a6dd44b69c4f318091f2047d707035#diff-05f3fe8941076453942a8c059b409009 

Using the script, I met some problems making the
initramfs.gz. It confused me a lot... I don't have busybox under
/usr/bin or /usr/sbin. Where to get it?

(host)$./go.sh nfs_tcp

File /usr/sbin/busybox could not be opened for reading
 line 55
File /lib64/libtirpc.so.3 could not be opened for reading
 line 306
File nc-vsock could not be opened for reading
 line 321
File ../netperf-2.7.0/src/netserver could not be opened for reading
 line 325

It results in guest kernel_panic when gdb launches the guest:

[    0.425738] Failed to execute /init (error -2)
[    0.426074] Kernel panic - not syncing: No working init found.  Try 
passing .
[    0.427077] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0+ #3
[    0.427507] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), 
BIOS rel-4
[    0.428354] Call Trace:
[    0.428538]  dump_stack+0x63/0x89
[    0.428774]  ? rest_init+0x60/0xc0
[    0.429017]  panic+0xeb/0x245
[    0.429225]  ? putname+0x53/0x60
[    0.429455]  ? rest_init+0xc0/0xc0
[    0.429722]  kernel_init+0xf1/0x104
[    0.430017]  ret_from_fork+0x25/0x30

Looking forward to the kind reply.
BTW, for the following questions that I sent two days ago, I have some
ideas in mind and it could be ignored now.

Jing

> I have updated both host and guest kernel with vsock-nfsd repo and 
> installed nfs-utils in both host and guest successfully.
>
> There're two different manuals in 
> https://www.spinics.net/lists/linux-nfs/msg64563.html(Quickstart 3~7) 
> and nfs-utils (README step 3 DAEMON STARTUP ORDER).
> Which one should be the best usage?
>
> For the first quickstart manual step 7-Mount the export from the guest, 
> two questions as follows.
> 1. why hypervisor's CID is 2? I didn't notice when it is specified?
> 2. Though I did step 3~7 successfully, I can't see the synchronistical 
> changing on host folder /export/ and guest /mnt? So how to test the 
> communcation between host and guest on the folder?
>
> Thanks again!
>
> Jing
[...]
> > Stefan