diff options
Diffstat (limited to 'arch/mips/kernel/ftrace.c')
| -rw-r--r-- | arch/mips/kernel/ftrace.c | 56 |
1 files changed, 41 insertions, 15 deletions
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c index e981a497c98..e363fc69aab 100644 --- a/arch/mips/kernel/ftrace.c +++ b/arch/mips/kernel/ftrace.c @@ -27,7 +27,13 @@ static unsigned int ftrace_nop = 0x00000000; static int ftrace_modify_code(unsigned long ip, unsigned int new_code) { - *(unsigned int *)ip = new_code; + int faulted; + + /* *(unsigned int *)ip = new_code; */ + safe_store_code(new_code, ip, faulted); + + if (unlikely(faulted)) + return -EFAULT; flush_icache_range(ip, ip + 8); @@ -41,14 +47,20 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr) { unsigned int new; + int faulted; unsigned long ip = rec->ip; /* We have compiled module with -mlong-calls, but compiled the kernel * without it, we need to cope with them respectively. */ if (ip & 0x40000000) { /* record it for ftrace_make_call */ - if (lui_v1 == 0) - lui_v1 = *(unsigned int *)ip; + if (lui_v1 == 0) { + /* lui_v1 = *(unsigned int *)ip; */ + safe_load_code(lui_v1, ip, faulted); + + if (unlikely(faulted)) + return -EFAULT; + } /* lui v1, hi_16bit_of_mcount --> b 1f (0x10000004) * addiu v1, v1, low_16bit_of_mcount @@ -147,6 +159,7 @@ unsigned long ftrace_get_parent_addr(unsigned long self_addr, { unsigned long sp, ip, ra; unsigned int code; + int faulted; /* in module or kernel? */ if (self_addr & 0x40000000) { @@ -162,8 +175,11 @@ unsigned long ftrace_get_parent_addr(unsigned long self_addr, do { ip -= 4; - /* get the code at "ip" */ - code = *(unsigned int *)ip; + /* get the code at "ip": code = *(unsigned int *)ip; */ + safe_load_code(code, ip, faulted); + + if (unlikely(faulted)) + return 0; /* If we hit the non-store instruction before finding where the * ra is stored, then this is a leaf function and it does not @@ -174,11 +190,14 @@ unsigned long ftrace_get_parent_addr(unsigned long self_addr, } while (((code & S_RA_SP) != S_RA_SP)); sp = fp + (code & OFFSET_MASK); - ra = *(unsigned long *)sp; + + /* ra = *(unsigned long *)sp; */ + safe_load_stack(ra, sp, faulted); + if (unlikely(faulted)) + return 0; if (ra == parent) return sp; - return 0; } @@ -193,6 +212,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, struct ftrace_graph_ent trace; unsigned long return_hooker = (unsigned long) &return_to_handler; + int faulted; if (unlikely(atomic_read(¤t->tracing_graph_pause))) return; @@ -206,21 +226,23 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, * ftrace_get_parent_addr() does it! */ - old = *parent; + /* old = *parent; */ + safe_load_stack(old, parent, faulted); + if (unlikely(faulted)) + goto out; parent = (unsigned long *)ftrace_get_parent_addr(self_addr, old, (unsigned long)parent, fp); - /* If fails when getting the stack address of the non-leaf function's * ra, stop function graph tracer and return */ - if (parent == 0) { - ftrace_graph_stop(); - WARN_ON(1); - return; - } + if (parent == 0) + goto out; - *parent = return_hooker; + /* *parent = return_hooker; */ + safe_store_stack(return_hooker, parent, faulted); + if (unlikely(faulted)) + goto out; if (ftrace_push_return_trace(old, self_addr, &trace.depth, fp) == -EBUSY) { @@ -235,5 +257,9 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, current->curr_ret_stack--; *parent = old; } + return; +out: + ftrace_graph_stop(); + WARN_ON(1); } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |