On Tue, 29 Sep 2026 09:39:36 +0100 Bruce Richardson <[email protected]> wrote:
> On Mon, Sep 28, 2026 at 04:15:58PM -0700, Stephen Hemminger wrote: > > Many parts of DPDK will fail with divide by zero and > > other errors if the initialization logic ever TSC hz was ever > > determined to be zero. This might happen on a broken get_tsc_freq_arch() > > or bad emulation in QEMU. > > > > If TSC hz is zero, log the error and propagate back to > > fail rte_eal_init(). > > > > This fix doesn't need to go to stable since it is a purely > > theoretical problem; we aren't getting divide by zero reports > > from users. > > > > How was this discovered? Is there a coverity issue id, or was it just AI > discovered? It was part of review of pcapng timestamp calculation. Kind of funny, AI spotted overflow (which I verified) in the code which it had previously helped write. Then it was asking it self, "what if TSC was 0". I didn't see how this could happen unless QEMU had some broken CPU emulation. To me it seemed best to fail fast and die in a safer manner.
