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McKenney wrote: > On Wed, Jan 06, 2021 at 11:28:00AM -0500, Rik van Riel wrote: > > > + wdagain_nsec = clocksource_cyc2ns(delta, watchdog- > > > mult, watchdog->shift); > > + if (wdagain_nsec < 0 || wdagain_nsec > > > WATCHDOG_MAX_SKEW) { > > + wderr_nsec = wdagain_nsec; > > + if (nretries++ < max_read_retries) > > + goto retry; > > + } > > > > Given that clocksource_cyc2ns uses unsigned multiplication > > followed by a right shift, do we need to test for <0? > > I am worried about the possibility of the "shift" argument to > clocksource_cyc2ns() being zero. For example, unless I am missing > something, clocksource_tsc has a zero .shift field. Oh, good point!