Index: head/sys/conf/files
===================================================================
--- head/sys/conf/files
+++ head/sys/conf/files
@@ -635,22 +635,22 @@
 contrib/ngatm/netnatm/sig/sig_verify.c optional ngatm_uni \
 	compile-with "${NORMAL_C} -I$S/contrib/ngatm"
 # Zstd
-contrib/zstd/lib/freebsd/zstd_kmalloc.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/common/zstd_common.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/common/fse_decompress.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/common/entropy_common.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/common/error_private.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/common/xxhash.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/zstd_compress.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/fse_compress.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/huf_compress.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/zstd_double_fast.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/zstd_fast.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/zstd_lazy.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/zstd_ldm.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/compress/zstd_opt.c		standard compile-with ${ZSTD_C}
-contrib/zstd/lib/decompress/zstd_decompress.c	standard compile-with ${ZSTD_C}
-contrib/zstd/lib/decompress/huf_decompress.c	standard compile-with ${ZSTD_C}
+contrib/zstd/lib/freebsd/zstd_kmalloc.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/common/zstd_common.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/common/fse_decompress.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/common/entropy_common.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/common/error_private.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/common/xxhash.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/zstd_compress.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/fse_compress.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/huf_compress.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/zstd_double_fast.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/zstd_fast.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/zstd_lazy.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/zstd_ldm.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/compress/zstd_opt.c		optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/decompress/zstd_decompress.c	optional zstdio compile-with ${ZSTD_C}
+contrib/zstd/lib/decompress/huf_decompress.c	optional zstdio compile-with ${ZSTD_C}
 # Blake 2
 contrib/libb2/blake2b-ref.c	optional crypto | ipsec | ipsec_support \
 	compile-with "${NORMAL_C} -I$S/crypto/blake2 -Wno-cast-qual -DSUFFIX=_ref -Wno-unused-function"
Index: head/sys/conf/files.mips
===================================================================
--- head/sys/conf/files.mips
+++ head/sys/conf/files.mips
@@ -113,4 +113,4 @@
 cddl/dev/fbt/mips/fbt_isa.c				optional dtrace_fbt | dtraceall compile-with "${FBT_C}"
 
 # Zstd
-contrib/zstd/lib/freebsd/zstd_kfreebsd.c		standard compile-with ${ZSTD_C}
+contrib/zstd/lib/freebsd/zstd_kfreebsd.c		optional zstdio compile-with ${ZSTD_C}
Index: head/sys/conf/files.riscv
===================================================================
--- head/sys/conf/files.riscv
+++ head/sys/conf/files.riscv
@@ -63,4 +63,4 @@
 riscv/riscv/vm_machdep.c	standard
 
 # Zstd
-contrib/zstd/lib/freebsd/zstd_kfreebsd.c		standard compile-with ${ZSTD_C}
+contrib/zstd/lib/freebsd/zstd_kfreebsd.c		optional zstdio compile-with ${ZSTD_C}
Index: head/sys/mips/conf/std.MALTA
===================================================================
--- head/sys/mips/conf/std.MALTA
+++ head/sys/mips/conf/std.MALTA
@@ -45,6 +45,9 @@
 #options 	WITNESS			#Enable checks to detect deadlocks and cycles
 #options 	WITNESS_SKIPSPIN	#Don't run witness on spinlocks for speed
 
+# Kernel dump features.
+options		ZSTDIO			# zstd-compressed kernel and user dumps
+
 device		loop
 device		ether
 device		le
Index: head/sys/riscv/conf/GENERIC
===================================================================
--- head/sys/riscv/conf/GENERIC
+++ head/sys/riscv/conf/GENERIC
@@ -116,6 +116,9 @@
 # options 	EARLY_PRINTF
 # options 	VERBOSE_SYSINIT
 
+# Kernel dump features.
+options		ZSTDIO			# zstd-compressed kernel and user dumps
+
 # Pseudo devices.
 device		loop		# Network loopback
 device		random		# Entropy device