view src/os_cpu/linux_x86/vm/os_linux_x86.hpp @ 4956:418fb371f2b9

8023956: Provide a work-around to broken Linux 32 bit "Exec Shield" using CS for NX emulation (crashing with SI_KERNEL) Summary: Execute some code at a high virtual address value, and keep mapped Reviewed-by: coleenp, zgu
author dsimms
date Wed, 25 Sep 2013 13:58:13 +0200
parents 7ab5f6318694
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  static void setup_fpu();
  static bool supports_sse();

  static jlong rdtsc();

  static bool is_allocatable(size_t bytes);

  // Used to register dynamic code cache area with the OS
  // Note: Currently only used in 64 bit Windows implementations
  static bool register_code_area(char *low, char *high) { return true; }

   * Work-around for broken NX emulation using CS limit, Red Hat patch "Exec-Shield"
   * (IA32 only).
   * Map and execute at a high VA to prevent CS lazy updates race with SMP MM
   * invalidation.Further code generation by the JVM will no longer cause CS limit
   * updates.
   * Affects IA32: RHEL 5 & 6, Ubuntu 10.04 (LTS), 10.10, 11.04, 11.10, 12.04.
   * @see JDK-8023956
  static void workaround_expand_exec_shield_cs_limit();