| Message ID | 20200429020531.20684-5-cmr@informatik.wtf (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Use per-CPU temporary mappings for patching | expand |
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 26f06cdb5d7e..cfbdef90384e 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -46,6 +46,13 @@ int raw_patch_instruction(unsigned int *addr, unsigned int instr) static struct mm_struct *patching_mm __ro_after_init; static unsigned long patching_addr __ro_after_init; +#ifdef CONFIG_LKDTM +unsigned long read_cpu_patching_addr(unsigned int cpu) +{ + return patching_addr; +} +#endif + void __init poking_init(void) { spinlock_t *ptl; /* for protecting pte table */
When live patching a STRICT_RWX kernel, 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@informatik.wtf> --- arch/powerpc/lib/code-patching.c | 7 +++++++ 1 file changed, 7 insertions(+)