On 26/11/13 18:15, Ingo Molnar wrote: > > * Adrian Hunter <[email protected]> wrote: > >> The logic was not looking in the buildid cache for kcore >> if the host kernel buildid did not match the recorded >> kernel buildid. > > It would be nice to also include the specific failure mode in the > changelog: exactly how can users run into this. That will be more > useful to most people reading these changelogs than a more abstract > bug description.
The preconditions for the problem are that kcore is in the buildid cache and that the running kernel has a different buildid e.g. $ perf buildid-list | grep kernel.kallsyms b18fbe769dea12513028a4287dae02efc1582c29 [kernel.kallsyms] $ perf record -o /tmp/junk true >/dev/null 2>&1 ; perf buildid-list -i /tmp/junk | grep kernel.kallsyms 504f9fd9328c40714995ce76fe1354c6e90136ce [kernel.kallsyms] Before the patch: $ perf script -v >out.txt build id event received for [kernel.kallsyms]: b18fbe769dea12513028a4287dae02efc1582c29 <SNIP> Using /home/ahunter/.debug/[kernel.kallsyms]/b18fbe769dea12513028a4287dae02efc1582c29 for symbols perf script stopped After the patch: $ perf script -v >out.txt build id event received for [kernel.kallsyms]: b18fbe769dea12513028a4287dae02efc1582c29 <SNIP> Using /home/ahunter/.debug/[kernel.kcore]/b18fbe769dea12513028a4287dae02efc1582c29/2013112617084061/kcore for kernel object code Using /home/ahunter/.debug/[kernel.kcore]/b18fbe769dea12513028a4287dae02efc1582c29/2013112617084061/kallsyms for symbols perf script stopped -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
