[CRIU] [PATCH] test/zdtm: do not allow running with --lazy-pages on kernel without uffd

[Mike Rapoport]

On Mon, Jul 10, 2017 at 12:20:00PM +0300, Pavel Emelyanov wrote:
> On 07/10/2017 11:48 AM, Mike Rapoport wrote:
> > On Mon, Jul 10, 2017 at 11:32:09AM +0300, Pavel Emelyanov wrote:
> >> On 07/09/2017 09:12 AM, Mike Rapoport wrote:
> >>> Raise an exception for kernels that do not have userfaultfd. For the
> >>> kernels that have userfaultfd but do not provide non-cooperative events
> >>> (4.3 - 4.10) warn about incomplete feature.
> >>>
> >>> Fixes: #363
> >>>
> >>> Signed-off-by: Mike Rapoport <rppt at linux.vnet.ibm.com>
> >>> ---
> >>>  test/zdtm.py | 10 ++++++++++
> >>>  1 file changed, 10 insertions(+)
> >>>
> >>> diff --git a/test/zdtm.py b/test/zdtm.py
> >>> index 2ee76cd..e6d2701 100755
> >>> --- a/test/zdtm.py
> >>> +++ b/test/zdtm.py
> >>> @@ -1767,6 +1767,16 @@ def run_tests(opts):
> >>>  		if subprocess.Popen(["ip", "netns", "exec", "zdtm_netns", "ip", "link", "set", "up", "dev", "lo"]).wait():
> >>>  			raise Exception("ip link set up dev lo")
> >>>  
> >>> +	if opts['lazy_pages'] or opts['remote_lazy_pages']:
> >>> +		check = subprocess.Popen([criu_bin, "check", "--feature", "lazy_pages"], stderr = subprocess.PIPE)
> >>
> >> There's a helper for that:
> >>
> >>         if opts['pre'] or opts['snaps']:
> >>                 if not criu.check("mem_dirty_track"):
> >>                         print "Tracking memory is not available"
> >>                         return
> >>
> >> so you can do it with
> >>
> >> 	if not criu.check("lazy_pages"):
> >> 		<bail-out>
> > 
> > It will return 1 even if uffd is present, but it still does not have
> > non-cooperative events. For instance, in travis ;-)
> 
> Then there should be one more feature in criu, not just lazy_pages :) Parsing
> stdout of it will break some day soon.

Hmm, I wouldn't want criu check to report that lazy-pages-something is
available for kernels older than 4.11...
 
> -- Pavel
> 
> >>> +		ret = check.wait()
> >>> +		err = ''.join(check.stderr.readlines())
> >>> +		if ret:
> >>> +			if "UFFD is not supported" in err:
> >>> +				raise Exception("UFFD is not supported, cannot run with --lazy-pages")
> >>> +			# Most test will work with 4.3 - 4.10
> >>> +			print "WARNING: UFFD is missing essentail features"
> >>> +
> >>>  	l = launcher(opts, len(torun))
> >>>  	try:
> >>>  		for t in torun:
> >>>
> >>
> > 
> 

-- 
Sincerely yours,
Mike.