[LU-5304] kernel allocated memroy can be memset up to 3 times

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.5.1
• Labels: patch
• Severity: 3
• Assignee: Cliff White (Inactive)
• Reporter: Frank Zago (Inactive)

Description

In some case the memory allocated by lustre could be zero-out twice (kmalloc followed by memset in LIBCFS_ALLOC_*, followed by another memset in the source code).

Additionally if GFP_ZERO is set, then the kernel will zero out the
block too. Surely that can't be too good for performance.

cfs_cpt_malloc() has a similar issue.