bug#33360: Guix does not error pretty when filesystem is ro

bug#33360: Guix does not error pretty when filesystem is ro

[swedebugia]

Hi

Today I booted up my pc from standby.

Qemu was running GuixSD from a cow on an USB-disk.

It had remounted ro and I got weird errors from guix when trying to build.

All other programs just stated the obvious:

"Cannot write to bla bla - read-only filesystem."

Guix of course tried to do a lot but failed of course.

--

Could we add a simple check to the commands that rely on writing to the 
filesystem?

-- 
Cheers Swedebugia

bug#33360: Guix does not error pretty when filesystem is ro

[Ludovic Courtès]

Hello,

swedebugia <swedebugia@riseup.net> skribis:

> Today I booted up my pc from standby.
>
> Qemu was running GuixSD from a cow on an USB-disk.
>
> It had remounted ro and I got weird errors from guix when trying to build.
>
> All other programs just stated the obvious:
>
> "Cannot write to bla bla - read-only filesystem."
>
> Guix of course tried to do a lot but failed of course.

Could you paste the exact command you run and its output?

TIA,
Ludo’.

bug#33360: Guix does not error pretty when filesystem is ro

[swedebugia]

On 2018-11-14 12:21, Ludovic Courtès wrote:
> Hello,
> 
> swedebugia <swedebugia@riseup.net> skribis:
> 
>> Today I booted up my pc from standby.
>>
>> Qemu was running GuixSD from a cow on an USB-disk.
>>
>> It had remounted ro and I got weird errors from guix when trying to build.
>>
>> All other programs just stated the obvious:
>>
>> "Cannot write to bla bla - read-only filesystem."
>>
>> Guix of course tried to do a lot but failed of course.
> 
> Could you paste the exact command you run and its output?

I did not succede in reproducing. This time I suspended my pc multiple 
times but qemu/the kernel did not remount / ro.

So I janked the usb out and back in and that did the trick if I ran a 
complicated command while it was out (guix build did the trick) :D

sdb@komputilo ~$ mount
none on /proc type proc (rw,relatime)
none on /dev type devtmpfs 
(rw,relatime,size=1002304k,nr_inodes=250576,mode=755)
none on /sys type sysfs (rw,relatime)
/dev/sda1 on / type ext4 (ro,relatime)
none on /dev/pts type devpts (rw,relatime,gid=996,mode=620,ptmxmode=000)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,relatime)
/dev/sda1 on /gnu/store type ext4 (ro,relatime)
sdb@komputilo ~$ guix --version
guix (GNU Guix) 1f44934fb6e2cefccbecd4fa347025349fa9ff76

Unfortunately it errored nicely this time:

sdb@komputilo ~/guix-tree [env]$ ./pre-inst-env guix build hello -K 
--substitute-urls="http://berlin.guixsd.org http://mirror.hydra.gnu.org"
guix build: error: fport_read: Connection reset by peer

Then the ssh terminal freezes. (qemu window shows a nice "kernel panic - 
not syncing: Attempted to kill init!" :)

Closed the bug.

-- 
Cheers Swedebugia