Commit 6596f1121b added a '-B' option to the list command to allow more efficient enumeration of longer lists. Unfortunately there is a small bug with this option where it may incorrectly flag a loop length of '0' on list of length 1. It is impossible to have a loop of length 0 and we can easily avoid the bug by looking at 'count'.

Example: crash> mutex.wait_list 0xffff8801070d6958 wait_list = 0xffff88010802bd08 crash> struct -o mutex.wait_list struct mutex { [8] struct list_head *wait_list; } crash> list -B -H 0xffff8801070d6960 -o mutex_waiter.list -s mutex_waiter.task ffff88010802bd08 task = 0xffff88013e7d7520 list: loop detected, loop length: 0 crash> list -H 0xffff8801070d6960 -o mutex_waiter.list -s mutex_waiter.task ffff88010802bd08 task = 0xffff88013e7d7520 crash> Fixes: 6596f1121b Signed-off-by: Dave Wysochanski <dwysocha(a)redhat.com&gt; --- tools.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools.c b/tools.c index f32e62f..85c8166 100644 --- a/tools.c +++ b/tools.c @@ -4146,7 +4146,7 @@ do_list_no_hash(struct list_data *ld) return -1; if (!brent_loop_detect) { - if (brent_x == brent_y) { + if (count > 1 && brent_x == brent_y) { brent_loop_detect = 1; error(INFO, "loop detected, loop length: %ld\n", brent_lambda); /* reset x and y to start; advance y loop length */ -- 1.8.3.1