On Saturday 06 September 2014, Sami Kerola wrote: > On 3 September 2014 23:19, Ruediger Meier <sweet_f_a@xxxxxx> wrote: > > On Wednesday 03 September 2014, Adam Sampson wrote: > >> On Wed, Sep 03, 2014 at 12:54:27PM +0200, Karel Zak wrote: > >> > - make ipcs limit calculations work when numbers are large > >> > >> That change isn't right -- it reverses the sense of the test, > >> making the testcase fail on 3.16 again. Patch attached. > > > > Your patch seems to be correct except that it should be "<=" > > instead of "<": > > if [ $(bc <<<"2^64 / $PAGE_SIZE <= $SHMALL") -eq 1 ]; then > > to have the same (correct) behavior like before 3a9ec12d. > > > > The mistake in 3a9ec12d happened probably because Sami tried to > > avoid "greater than" relations. but for my brain this line would be > > still more easy to read: > > if [ $(bc <<<"$SHMALL >= 2^64 / $PAGE_SIZE") -eq 1 ]; then > > Maybe that's why me and others have not noticed the mistake when > > reviewing that patch. > > Hi Adam, Rudi, and others, > > It was not good summer for me. This is second totally stupid bug > from me. This time the reason is I tested the logic by flipping it > around to see it works, and accidentally wrong version end up to > submission. > > Here is the change from Adams attachment, with CC and Reviewed-by > lines, and round braces to ensure bc does calculation always in > correct order. > > --->8---- > From: Adam Sampson <ats@xxxxxxxxx> > Date: Wed, 3 Sep 2014 16:49:40 +0100 > Subject: tests: fix the ipcs test for shmall being too big to show > > It was correct when originally introduced, but the shell overflow fix > in 3a9ec12d6664527fad9c56347c88f3447d6c0856 accidentally reversed the > sense of the test. > > CC: Ruediger Meier <sweet_f_a@xxxxxx> > Reviewed-by: Sami Kerola <kerolasa@xxxxxx> > Signed-off-by: Adam Sampson <ats@xxxxxxxxx> > --- > tests/ts/ipcs/limits2 | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tests/ts/ipcs/limits2 b/tests/ts/ipcs/limits2 > index 1a49c46..10f7514 100755 > --- a/tests/ts/ipcs/limits2 > +++ b/tests/ts/ipcs/limits2 > @@ -29,7 +29,7 @@ ts_check_prog "bc" > > # TODO https://github.com/karelzak/util-linux/issues/51 > SHMALL=$(</proc/sys/kernel/shmall) > -if [ $(bc <<<"2^64 / $PAGE_SIZE < $SHMALL") -ne 1 ]; then > +if [ $(bc <<<"(2^64 / $PAGE_SIZE) < $SHMALL") -eq 1 ]; then It still must be "<=": +if [ $(bc <<<"(2^64 / $PAGE_SIZE) <= $SHMALL") -eq 1 ]; then You can test the logic like this on any x86_64 system (assuming page size 4096): $ sudo sh -c "echo 4503599627370496 > /proc/sys/kernel/shmall" $ make check TS_OPTS='ipcs' 4503599627370496 (= 2^64 / 4096) is the smallest value where our ipcs binary fails (issue #51). > TS_KNOWN_FAIL="yes" > fi cu, Rudi -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
