Re: [Crash-utility] [PATCH 1/2] tree: no need to bail out on tree corruption, skip the node and move on instead

Hi Dave, On Thu, Apr 12, 2018 at 3:32 PM, Dave Anderson <anderson(a)redhat.com&gt; wrote: > > Hi Daniel, > > If the tree is corrupted, I would think that you would want to know the > specifics, i.e., aside from the somewhat cryptic readmem() error message. > > Perhaps it would be worth printing a more meaningful error message, > something like: > > tree: rb_node: <address>: corrupt rb_left pointer: <address> Yeah, that's a good point. I just tried a simple s/FAULT_ON_ERROR/RETURN_ON_ERROR/ and checked if that works, but keeping the former behaviour with regards to error reporting. But having a meaningful error output would be nice. Do you prefer a followup patch or amend to this one?

--nX > That way you could do the 2 readmem() calls w/RETURN_ON_ERROR|QUIET, and > just have the concise error message. > > Thanks, > Dave > > ----- Original Message ----- >> --- >> tools.c | 23 ++++++++++++----------- >> 1 file changed, 12 insertions(+), 11 deletions(-) >> >> diff --git a/tools.c b/tools.c >> index 186b703463a5..992f4776281a 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; >> + char new_pos[BUFSIZE]; >> static struct req_entry **e; >> >> if (!node_p) >> @@ -4430,16 +4430,17 @@ 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); >> + if ( readmem(node_p+OFFSET(rb_node_rb_left), KVADDR, &new_p, >> + sizeof(void *), "rb_node rb_left", RETURN_ON_ERROR)) >> { >> + sprintf(new_pos, "%s/l", pos); >> + rbtree_iteration(new_p, td, new_pos); >> + } >> >> - rbtree_iteration(left_p, td, left_pos); >> - rbtree_iteration(right_p, td, right_pos); >> + if ( readmem(node_p+OFFSET(rb_node_rb_right), KVADDR, &new_p, >> + sizeof(void *), "rb_node rb_right", >> RETURN_ON_ERROR)) { >> + sprintf(new_pos, "%s/r", pos); >> + rbtree_iteration(new_p, td, new_pos); >> + } >> } >> >> void >> -- >> 2.16.2 >> >> -- >> Crash-utility mailing list >> Crash-utility(a)redhat.com >> https://www.redhat.com/mailman/listinfo/crash-utility >>