diff options
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 27 | ||||
| -rw-r--r-- | arch/powerpc/kernel/ftrace.c | 13 |
2 files changed, 37 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 9f61fd61f27..abfc3233047 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -971,6 +971,28 @@ _GLOBAL(ftrace_graph_caller) _GLOBAL(return_to_handler) /* need to save return values */ + std r4, -24(r1) + std r3, -16(r1) + std r31, -8(r1) + mr r31, r1 + stdu r1, -112(r1) + + bl .ftrace_return_to_handler + nop + + /* return value has real return address */ + mtlr r3 + + ld r1, 0(r1) + ld r4, -24(r1) + ld r3, -16(r1) + ld r31, -8(r1) + + /* Jump back to real return address */ + blr + +_GLOBAL(mod_return_to_handler) + /* need to save return values */ std r4, -32(r1) std r3, -24(r1) /* save TOC */ @@ -979,7 +1001,10 @@ _GLOBAL(return_to_handler) mr r31, r1 stdu r1, -112(r1) - /* update the TOC */ + /* + * We are in a module using the module's TOC. + * Switch to our TOC to run inside the core kernel. + */ LOAD_REG_IMMEDIATE(r4,ftrace_return_to_handler) ld r2, 8(r4) diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c index 7538b944fa5..5c6dfa97e83 100644 --- a/arch/powerpc/kernel/ftrace.c +++ b/arch/powerpc/kernel/ftrace.c @@ -567,6 +567,10 @@ int ftrace_disable_ftrace_graph_caller(void) } #endif /* CONFIG_DYNAMIC_FTRACE */ +#ifdef CONFIG_PPC64 +extern void mod_return_to_handler(void); +#endif + /* * Hook the return address and push it in the stack of return addrs * in current thread info. @@ -577,12 +581,17 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) unsigned long long calltime; int faulted; struct ftrace_graph_ent trace; - unsigned long return_hooker = (unsigned long) - &return_to_handler; + unsigned long return_hooker = (unsigned long)&return_to_handler; if (unlikely(atomic_read(¤t->tracing_graph_pause))) return; +#if CONFIG_PPC64 + /* non core kernel code needs to save and restore the TOC */ + if (REGION_ID(self_addr) != KERNEL_REGION_ID) + return_hooker = (unsigned long)&mod_return_to_handler; +#endif + return_hooker = GET_ADDR(return_hooker); /* |