Locally I need to get Lustre built against an alpha kernel for RHEL7.3 beta. I started with the ldiskfs-3.10-rhel7.2.series, and hit the following issue.

It appears that patch 923ae0ff9250430133b3310fe62c47538cf1cbc1 from the upsteam linux kernel is in this new pre-RHEL7.3 kernel. The patch introduces ext4 DAX support.

It adds the following define to fs/ext4/ext4.h:

+#ifdef CONFIG_FS_DAX
+#define EXT4_MOUNT_DAX                 0x00200 /* Direct Access */
+#else
+#define EXT4_MOUNT_DAX                 0
+#endif

The ext4-data-in-dirent.patch introduces EXT4_MOUNT_DIRDATA with the same value:

#define EXT4_MOUNT_DIRDATA             0x00200 /* Data in directory entries*/

I am going to need guidance on that flag conflict.