diff --git a/kmod/src/Makefile.kernelcompat b/kmod/src/Makefile.kernelcompat
index 7e3235b5..ee3de8f9 100644
--- a/kmod/src/Makefile.kernelcompat
+++ b/kmod/src/Makefile.kernelcompat
@@ -396,3 +396,11 @@ endif
 ifneq (,$(shell grep 'extern void d_tmpfile.struct dentry' include/linux/dcache.h))
 ccflags-y += -DKC_D_TMPFILE_DENTRY
 endif
+
+#
+# v6.4-rc2-201-g0733ad800291
+#
+# New blk_mode_t replaces abuse of fmode_t
+ifneq (,$(shell grep 'typedef unsigned int __bitwise blk_mode_t' include/linux/blkdev.h))
+ccflags-y += -DKC_HAVE_BLK_MODE_T
+endif
diff --git a/kmod/src/super.h b/kmod/src/super.h
index 03c6a6ea..45ec8450 100644
--- a/kmod/src/super.h
+++ b/kmod/src/super.h
@@ -101,7 +101,11 @@ static inline bool SCOUTFS_IS_META_BDEV(struct scoutfs_super_block *super_block)
 	return !!(le64_to_cpu(super_block->flags) & SCOUTFS_FLAG_IS_META_BDEV);
 }
 
+#ifdef KC_HAVE_BLK_MODE_T
+#define SCOUTFS_META_BDEV_MODE (BLK_OPEN_READ | BLK_OPEN_WRITE | BLK_OPEN_EXCL)
+#else
 #define SCOUTFS_META_BDEV_MODE (FMODE_READ | FMODE_WRITE | FMODE_EXCL)
+#endif
 
 static inline bool scoutfs_forcing_unmount(struct super_block *sb)
 {