If the first file specified for a job is not a block device file, the
ioscheduler option cannot be used. Trying to use this option can cause a
crash as that file du (struct disk_util) field is NULL. Prevent such
crash and signal the error by testing the file type, allowing only files
with the type FIO_TYPE_BLOCK to proceed with switching the IO scheduler.
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
---
backend.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/backend.c b/backend.c
index 52b4ca7e..18372a92 100644
--- a/backend.c
+++ b/backend.c
@@ -1356,6 +1356,12 @@ static int switch_ioscheduler(struct thread_data *td)
return 0;
assert(td->files && td->files[0]);
+ if (td->files[0]->filetype != FIO_TYPE_BLOCK) {
+ log_err("fio: cannot switch IO scheduler with file %s\n",
+ td->files[0]->file_name);
+ return -1;
+ }
+
sprintf(tmp, "%s/queue/scheduler", td->files[0]->du->sysfs_root);
f = fopen(tmp, "r+");
--
2.30.2
