This ticket reports the same issue than LU-5522.

It occured at customer site on Lustre version 2.5.3 with a few additional patches.

According to the Bull support team, the issue could be a side effect of the fix #10492 for LU-2827, which is one of the addtional patch we apply on top of 2.5.3.

I have posted the patch #13744 in b2_5, which is the backport of the master patch #11634 that fixes LU-5522.

If the support assumption is confirmed, since LU-2827 is integrated into the future 2.5.4 maintenance release, it will be required to have this fix in 2.5.4 also.