On Tue, 27 Aug 2024, Martin Doucha wrote: > On 23. 08. 24 23:59, NeilBrown wrote: > > On Fri, 23 Aug 2024, Petr Vorel wrote: > >> We discussed in v1 how to fix tests. Neil suggested to fix the test the way so > >> that it works on all kernels. As I note [1] > >> > >> 1) either we give up on checking the new functionality still works (if we > >> fallback to old behavior) > > > > I don't understand. What exactly do you mean by "the new > > functionality". > > As I understand it there is no new functionality. All there was was and > > information leak between network namespaces, and we stopped the leak. > > Do you consider that to be new functionality? > > The new functionality is that the patches add a new file to network > namespaces: /proc/net/rpc/nfs. This file did not exist outside the root > network namespace at least on some of the kernels where we still need to > run this test. So the question is: How aggressively do we want to > enforce backporting of these NFS patches into distros with older kernels? Thanks for explaining that. I had assumed that the the file was always visible from all name spaces, but before the fix every namespace saw the same file. Clearly I was wrong. > > We have 3 options how to fix the test depending on the answer: > 1) Don't enforce at all. We'll check whether /proc/net/rpc/nfs exists in > the client namespace and read it only if it does. Otherwise we'll fall > back on the global file. > 2) Enforce aggressively. We'll hardcode a minimal kernel version into > the test (e.g. v5.4) and if the procfile doesn't exist on any newer > kernel, it's a bug. > 3) Enforce on new kernels only. We'll set a hard requirement for kernel > v6.9+ as in option 2) and check for existence of the procfile on any > older kernels as in option 1). I think there are two totally separate questions here. 1/ How to fix the existing test to work on new and old kernels. The existing test checked that the rpc count increased when NFS traffic happened. I think 1 is the correct fix. I don't think the test should check kernel version. 2/ We have discovered a bug and want to add a test to guard against regression. This should be a new test. That test can simply check if the given file exist in a non-init namespace. I have no particular opinion about testing kernel versions. A credible approach would be to choose the oldest kernel which it still maintained at the time that that bug was discovered. Or maybe create a list of kernel versions where were maintained at that time and only run the test on versions in that list, or after the last in the list. I really think there is value in having two different tests because we are testing two different things. Thanks, NeilBrown > > -- > Martin Doucha mdoucha@xxxxxxx > SW Quality Engineer > SUSE LINUX, s.r.o. > CORSO IIa > Krizikova 148/34 > 186 00 Prague 8 > Czech Republic > >
