Don't map systemcfg on Power in checkpoint mode #7351
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On Power `omrtime_current_time_millis` and `omrtime_hires_clock` can use the timebase register to very quickly get the current time. This requires mmapping the special `/proc/ppc64/systemcfg` file. Some security modules (e.g. SELinux) prevent systemcfg from being mapped by user processes. If we take a checkpoint in an environment that that allows systemcfg to be mapped it will not be restorable in an environment that forbids it. This patch disables the mapping of systemcfg in checkpoint mode, which will force the omrtime functions to fall back to conventional Linux time APIs. Signed-off-by: Younes Manton <[email protected]>
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On Power
omrtime_current_time_millisandomrtime_hires_clockcan use the timebase register to very quickly get the current time. This requires mmapping the special/proc/ppc64/systemcfgfile.Some security modules (e.g. SELinux) prevent systemcfg from being mapped by user processes. If we take a checkpoint in an environment that that allows systemcfg to be mapped it will not be restorable in an environment that forbids it.
This patch disables the mapping of systemcfg in checkpoint mode, which will force the omrtime functions to fall back to conventional Linux time APIs.