On 14.03.25 16:56, Brendan Jackman wrote:
Even if it's a bug in QEMU, I think it is worth working around this
one way or another. QEMU by far the most practical way to run these
tests, and virtme-ng is probably the most popular/practical way to do
that.
I'm afraid yes. Although allocating temp files form 9pfs is rather ...
weird. :) One would assume that /tmp is usually backed by tmpfs. But well, a
disto can do what it wants.
Ah yeah but these tests also use mkstemp() in the CWD i.e. the
location of run_vmtests.sh, it isn't /tmp that is causing this at the
moment. (At some point I thought I was hitting the issue there too,
but I think I was mistaken, like just not reading the test logs
properly or something).
Ah, yes run_with_local_tmpfile() ... jep, I wrote that test, now my
memory comes back; we wanted to test with actual filesystems (e.g.,
ext4, xfs) easily.
I think even if we are confident it's just a bunch of broken
code that isn't even in Linux, it's pragmatic to spend a certain
amount of energy on having green tests there.
Yeah, we're trying ...
(Also, this f_type thing might be totally intentional specified
filesystem behaviour, I don't know).
I assume it's broken in various ways to mimic that you are a file system
which you are not.
Your approach is likely the easiest approach to deal with this 9pfs crap.
Can you document in the code+description better what we learned, and why we
cannot even trust f_type with crappy 9pfs?
Sure, I will be more verbose about it.
I've already sent v4 here:
https://lore.kernel.org/all/20250311-mm-selftests-v4-7-dec210a658f5@xxxxxxxxxx/
So I will wait and see if there are any comments on the v4, if there
are I'll spin the extra commentary into v5 otherwise send it as a
followup, does that sound OK?
You can just ask Andrew to fixup the comment or description in a reply
to the v4 patch. Andrew will let you know if he prefers a resend.
Thanks!
--
Cheers,
David / dhildenb
