Enabling Kernel Symbol Resolution - Enabling Kernel Symbol Resolution - 57368

To attribute the kernel samples to appropriate kernel functions, AMD uProf extracts required information from the /proc/kallsyms file. Exposing the kernel symbol addresses through /proc/ kallsyms requires setting of the appropriate value to the /proc/sys/kernel/kptr_restrict file as follows:

• Set /proc/sys/kernel/perf_event_paranoid to -1.
• Set /proc/sys/kernel/kptr_restrict to an appropriate value as follows:
  • 0: The kernel addresses are available without any limitations.
  • 1: The kernel addresses are available if the current user has a CAP_SYSLOG capability.
  • 2: The kernel addresses are hidden.

$ sudo echo -1 > /proc/sys/kernel/perf_event_paranoid

$ sudo sysctl -w kernel.perf_event_paranoid=-1

$ sudo echo 0 > /proc/sys/kernel/kptr_restrict

$ sudo sysctl -w kernel.kptr_restrict=0