@@ -184,4 +184,8 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name)
#define PPC_INST_STD_LR PPC_RAW_STD(_R0, _R1, PPC_LR_STKOFF)
#endif /* CONFIG_PPC64 */
+#if IS_BUILTIN(CONFIG_LKDTM) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)
+unsigned long read_cpu_patching_addr(unsigned int cpu);
+#endif
+
#endif /* _ASM_POWERPC_CODE_PATCHING_H */
@@ -47,6 +47,13 @@ int raw_patch_instruction(u32 *addr, struct ppc_inst instr)
#ifdef CONFIG_STRICT_KERNEL_RWX
static DEFINE_PER_CPU(struct vm_struct *, text_poke_area);
+#if IS_BUILTIN(CONFIG_LKDTM)
+unsigned long read_cpu_patching_addr(unsigned int cpu)
+{
+ return (unsigned long)(per_cpu(text_poke_area, cpu))->addr;
+}
+#endif
+
static int text_area_cpu_up(unsigned int cpu)
{
struct vm_struct *area;
When live patching with STRICT_KERNEL_RWX a mapping is installed at a "patching address" with temporary write permissions. Provide a LKDTM-only accessor function for this address in preparation for a LKDTM test which attempts to "hijack" this mapping by writing to it from another CPU. Signed-off-by: Christopher M. Riedl <cmr@linux.ibm.com> --- arch/powerpc/include/asm/code-patching.h | 4 ++++ arch/powerpc/lib/code-patching.c | 7 +++++++ 2 files changed, 11 insertions(+)