diff options
Diffstat (limited to 'arch/powerpc/kernel/process.c')
| -rw-r--r-- | arch/powerpc/kernel/process.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 0a3216433051..c930ac38e59f 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1016,9 +1016,13 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) #ifdef CONFIG_FUNCTION_GRAPH_TRACER int curr_frame = current->curr_ret_stack; extern void return_to_handler(void); - unsigned long addr = (unsigned long)return_to_handler; + unsigned long rth = (unsigned long)return_to_handler; + unsigned long mrth = -1; #ifdef CONFIG_PPC64 - addr = *(unsigned long*)addr; + extern void mod_return_to_handler(void); + rth = *(unsigned long *)rth; + mrth = (unsigned long)mod_return_to_handler; + mrth = *(unsigned long *)mrth; #endif #endif @@ -1044,7 +1048,7 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) if (!firstframe || ip != lr) { printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip); #ifdef CONFIG_FUNCTION_GRAPH_TRACER - if (ip == addr && curr_frame >= 0) { + if ((ip == rth || ip == mrth) && curr_frame >= 0) { printk(" (%pS)", (void *)current->ret_stack[curr_frame].ret); curr_frame--; @@ -1165,7 +1169,22 @@ static inline unsigned long brk_rnd(void) unsigned long arch_randomize_brk(struct mm_struct *mm) { - unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd()); + unsigned long base = mm->brk; + unsigned long ret; + +#ifdef CONFIG_PPC_STD_MMU_64 + /* + * If we are using 1TB segments and we are allowed to randomise + * the heap, we can put it above 1TB so it is backed by a 1TB + * segment. Otherwise the heap will be in the bottom 1TB + * which always uses 256MB segments and this may result in a + * performance penalty. + */ + if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T)) + base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T); +#endif + + ret = PAGE_ALIGN(base + brk_rnd()); if (ret < mm->brk) return mm->brk; |