After creating a raid array on top of a imsm container. Try to
grow the chunk size and the reshape will hang with zero progress.
The reason is the computation of sync_max_to_set value:
if (before_data_disks <= data_disks)
sync_max_to_set = sra->reshape_progress / data_disks;
else
sync_max_to_set = (sra->component_size * data_disks
- sra->reshape_progress) / data_disks;
Can produce a zero result. Which is then used to set the maximum
sync value, causing zero progress to the reshape. The change is to
test if the sync_max_to_set value is zero. And if so, set the sysfs
sync_max to "max".
Steps to Reproduce:
1. Create a container and RAID0 array
mdadm -CR /dev/md/imsm -e imsm -n2 /dev/nvme0n1 /dev/nvme1n1
mdadm -CR /dev/md/vol -l0 --chunk=16 -n2 /dev/nvme0n1 /dev/nvme1n1
2. Wait for resync
3. Try to grow the chunk size
mdadm --grow /dev/md/vol --chunk=256
Signed-off-by: Nigel Croxon <ncroxon@xxxxxxxxxx>
---
Grow.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Grow.c b/Grow.c
index 0f07a894..6c5021bc 100644
--- a/Grow.c
+++ b/Grow.c
@@ -943,7 +943,7 @@ int start_reshape(struct mdinfo *sra, int already_running,
if (!already_running)
sysfs_set_num(sra, NULL, "sync_min", sync_max_to_set);
- if (st->ss->external)
+ if (sync_max_to_set)
err = err ?: sysfs_set_num(sra, NULL, "sync_max", sync_max_to_set);
else
err = err ?: sysfs_set_str(sra, NULL, "sync_max", "max");
--
2.31.1
