* Yoshihiro Takahashi <ytakahashi at miraclelinux.com> wrote: > Hi. > > kdump hangs up by Sysrq+C trigger once in about 10 times in high load. > After the above occurs, kdump cannot collect vmcores with NMI button. > When waiting_for_crash_ipi does case more than 0, mdelay seem to make a > stall. > > While nmi_shootdown_cpus(), mdelay may not work since interruption is > disable. (ex. when crashing kernel by NMI interruption, all > interruption may be disabled.). > > So I think that it should use other way (TSC) instead of mdelay() in > nmi_shootdown_cpus(). mdelay uses either the tsc or CPU loops - neither stop while IRQs are disabled. Could you figure out exactly why it hangs in your case? Ingo
