Re: [PATCH] fcntl: Add 32bit filesystem mode

[Peter Maydell]

On Mon, 20 Apr 2020 at 12:38, Peter Maydell <address@hidden> wrote:
> Whoops, good point. I was testing this via lkvm, so it's
> actually using a 9p filesystem... I'll see if I can figure
> out how to test with an ext3 fs, which I think is the one
> we most care about.

After some effort wrestling with kvmtool (which assumes that
if you provide it a disk image then you must have wanted that
to be your rootfs and can only be persuaded otherwise via
some undocumented and arcane options), I did a test with ext4:

bash-4.4# /qemu-no-fix /readdir-bug
dir=0x76108
readdir(dir)=(nil)
errno=75: Value too large for defined data type
bash-4.4# /qemu-fixed /readdir-bug
dir=0x76108
readdir(dir)=0x76128
errno=0: Success

(where the host kernel has Linus' fcntl patch, qemu-no-fix
is a current-git-master QEMU and qemu-fixed is one with
the patch in my previous email).

So for Linus' patch:

Tested-by: Peter Maydell <address@hidden>

If 9pfs could be persuaded to honour the fcntl flag too
that would be really nice.

thanks
-- PMM