[LTP] [PATCH] tst_kvercmp: Handle larger kernel version numbers

[Edward Liaw]

Hi Petr,

On Tue, Oct 24, 2023 at 5:46 PM Edward Liaw <edliaw@google.com> wrote:
>
> On Tue, Oct 24, 2023, 4:14 PM Petr Vorel <pvorel@suse.cz> wrote:
>>
>> Hi Edward,
>>
>> > Current implementation can only handle revision numbers up to 256.  Bump
>> > this up to 1024 as some revision numbers are in the 300s.
>>
>> > Signed-off-by: Edward Liaw <edliaw@google.com>
>> > ---
>> >  lib/tst_kvercmp.c | 4 ++--
>> >  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> > diff --git a/lib/tst_kvercmp.c b/lib/tst_kvercmp.c
>> > index 552920fac..9e1a511af 100644
>> > --- a/lib/tst_kvercmp.c
>> > +++ b/lib/tst_kvercmp.c
>> > @@ -92,8 +92,8 @@ int tst_kvcmp(const char *cur_kver, int r1, int r2, int r3)
>> >                        cur_kver);
>> >       }
>>
>> > -     testver = (r1 << 16) + (r2 << 8) + r3;
>> > -     currver = (a1 << 16) + (a2 << 8) + a3;
>> > +     testver = (r1 << 20) + (r2 << 10) + r3;
>> > +     currver = (a1 << 20) + (a2 << 10) + a3;
>>
>> I wonder why you need this change. Number > 256 is actually only the third
>> number, but we haven't checked that so far. Do you plan to use it actually?
>
>
> It was causing the minor rev of the kernel I was running to overflow into the major rev, so a test that had a min kver of 4.19 was running and failing on a 4.14.327 kernel.

I remembered it incorrectly.  It was the mmap20 test with min_kver
4.15 that was failing on a 4.14.327 kernel.