[Crash-utility] [PATCH v2 1/3] tree: no need to bail out on tree corruption

instead skip the node reporting a proper error and move on v2: add friendly error messages instead of generic readmem failures --- tools.c | 33 +++++++++++++++++++++------------ 1 file changed, 21 insertions(+), 12 deletions(-) diff --git a/tools.c b/tools.c index 186b703463a5..7c7f65ac558b 100644 --- a/tools.c +++ b/tools.c @@ -4374,8 +4374,8 @@ rbtree_iteration(ulong node_p, struct tree_data *td, char *pos) { int i; uint print_radix; - ulong struct_p, left_p, right_p; - char left_pos[BUFSIZE], right_pos[BUFSIZE]; + ulong struct_p, new_p, test_p; + char new_pos[BUFSIZE]; static struct req_entry **e; if (!node_p) @@ -4430,16 +4430,25 @@ rbtree_iteration(ulong node_p, struct tree_data *td, char *pos) } } - readmem(node_p+OFFSET(rb_node_rb_left), KVADDR, &left_p, - sizeof(void *), "rb_node rb_left", FAULT_ON_ERROR); - readmem(node_p+OFFSET(rb_node_rb_right), KVADDR, &right_p, - sizeof(void *), "rb_node rb_right", FAULT_ON_ERROR); - - sprintf(left_pos, "%s/l", pos); - sprintf(right_pos, "%s/r", pos); - - rbtree_iteration(left_p, td, left_pos); - rbtree_iteration(right_p, td, right_pos); + if ( readmem(node_p+OFFSET(rb_node_rb_left), KVADDR, &new_p, + sizeof(void *), "rb_node rb_left", RETURN_ON_ERROR) && new_p) + if (readmem(new_p+OFFSET(rb_node_rb_left), KVADDR, &test_p, + sizeof(void *), "rb_node rb_left", RETURN_ON_ERROR|QUIET)) { + sprintf(new_pos, "%s/l", pos); + rbtree_iteration(new_p, td, new_pos); + } else + error(INFO, "rb_node: %lx: corrupted rb_left pointer: %lx\n", + node_p, new_p); + + if ( readmem(node_p+OFFSET(rb_node_rb_right), KVADDR, &new_p, + sizeof(void *), "rb_node rb_right", RETURN_ON_ERROR) && new_p) + if (readmem(new_p+OFFSET(rb_node_rb_left), KVADDR, &test_p, + sizeof(void *), "rb_node rb_left", RETURN_ON_ERROR|QUIET)) { + sprintf(new_pos, "%s/r", pos); + rbtree_iteration(new_p, td, new_pos); + } else + error(INFO, "rb_node: %lx: corrupted rb_right pointer: %lx\n", + node_p, new_p); } void -- 2.17.0