diff --git a/sys/conf/kern.pre.mk b/sys/conf/kern.pre.mk
index cb1703097836..4a0663f49753 100644
--- a/sys/conf/kern.pre.mk
+++ b/sys/conf/kern.pre.mk
@@ -1,365 +1,363 @@
 # $FreeBSD$
 
 # Part of a unified Makefile for building kernels.  This part contains all
 # of the definitions that need to be before %BEFORE_DEPEND.
 
 # Allow user to configure things that only effect src tree builds.
 # Note: This is duplicated from src.sys.mk to ensure that we include
 # /etc/src.conf when building the kernel. Kernels can be built without
 # the rest of /usr/src, but they still always process SRCCONF even though
 # the normal mechanisms to prevent that (compiling out of tree) won't
 # work. To ensure they do work, we have to duplicate thee few lines here.
 SRCCONF?=	/etc/src.conf
 .if (exists(${SRCCONF}) || ${SRCCONF} != "/etc/src.conf") && !target(_srcconf_included_)
 .include "${SRCCONF}"
 _srcconf_included_:
 .endif
 
 .include <bsd.own.mk>
 .include <bsd.compiler.mk>
 .include "kern.opts.mk"
 
 # The kernel build always occurs in the object directory which is .CURDIR.
 .if ${.MAKE.MODE:Unormal:Mmeta}
 .MAKE.MODE+=	curdirOk=yes
 .endif
 
 # The kernel build always expects .OBJDIR=.CURDIR.
 .OBJDIR: ${.CURDIR}
 
 .if defined(NO_OBJWALK) || ${MK_AUTO_OBJ} == "yes"
 NO_OBJWALK=		t
 NO_MODULES_OBJ=	t
 .endif
 .if !defined(NO_OBJWALK)
 _obj=		obj
 .endif
 
 # Can be overridden by makeoptions or /etc/make.conf
 KERNEL_KO?=	kernel
 KERNEL?=	kernel
 KODIR?=		/boot/${KERNEL}
 LDSCRIPT_NAME?=	ldscript.$M
 LDSCRIPT?=	$S/conf/${LDSCRIPT_NAME}
 
 M=		${MACHINE}
 
 AWK?=		awk
 CP?=		cp
 NM?=		nm
 OBJCOPY?=	objcopy
 SIZE?=		size
 
 .if defined(DEBUG)
 CTFFLAGS+=	-g
 .endif
 .if ${MACHINE_CPUARCH} == "amd64" && ${COMPILER_TYPE} != "clang"
 _COPTFLAGS_EXTRA=-frename-registers
 .else
 _COPTFLAGS_EXTRA=
 .endif
 COPTFLAGS?=-O2 -pipe ${_COPTFLAGS_EXTRA}
 .if !empty(COPTFLAGS:M-O[23s]) && empty(COPTFLAGS:M-fno-strict-aliasing)
 COPTFLAGS+= -fno-strict-aliasing
 .endif
 .if !defined(NO_CPU_COPTFLAGS)
 COPTFLAGS+= ${_CPUCFLAGS}
 .endif
 NOSTDINC= -nostdinc
 
 INCLUDES= ${NOSTDINC} ${INCLMAGIC} -I. -I$S -I$S/contrib/ck/include
 
 CFLAGS=	${COPTFLAGS} ${DEBUG}
 CFLAGS+= ${INCLUDES} -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h
 CFLAGS_PARAM_INLINE_UNIT_GROWTH?=100
 CFLAGS_PARAM_LARGE_FUNCTION_GROWTH?=1000
 .if ${MACHINE_CPUARCH} == "mips"
 CFLAGS_ARCH_PARAMS?=--param max-inline-insns-single=1000 -DMACHINE_ARCH='"${MACHINE_ARCH}"'
 .endif
 CFLAGS.gcc+= -fms-extensions -finline-limit=${INLINE_LIMIT}
 CFLAGS.gcc+= --param inline-unit-growth=${CFLAGS_PARAM_INLINE_UNIT_GROWTH}
 CFLAGS.gcc+= --param large-function-growth=${CFLAGS_PARAM_LARGE_FUNCTION_GROWTH}
 CFLAGS.gcc+= -fms-extensions
 .if defined(CFLAGS_ARCH_PARAMS)
 CFLAGS.gcc+=${CFLAGS_ARCH_PARAMS}
 .endif
 WERROR?=	-Werror
 # The following should be removed no earlier than LLVM11 being imported into the
 # tree, to ensure we don't regress the build.  LLVM11 and GCC10 will switch the
 # default over to -fno-common, making this redundant.
 CFLAGS+=	-fno-common
 
 # XXX LOCORE means "don't declare C stuff" not "for locore.s".
 ASM_CFLAGS= -x assembler-with-cpp -DLOCORE ${CFLAGS} ${ASM_CFLAGS.${.IMPSRC:T}} 
 
 .if defined(PROFLEVEL) && ${PROFLEVEL} >= 1
 CFLAGS+=	-DGPROF
 CFLAGS.gcc+=	-falign-functions=16
 .if ${PROFLEVEL} >= 2
 CFLAGS+=	-DGPROF4 -DGUPROF
 PROF=		-pg
 .if ${COMPILER_TYPE} == "gcc"
 PROF+=		-mprofiler-epilogue
 .endif
 .else
 PROF=		-pg
 .endif
 .endif
 DEFINED_PROF=	${PROF}
 
 KCSAN_ENABLED!=	grep KCSAN opt_global.h || true ; echo
 .if !empty(KCSAN_ENABLED)
 SAN_CFLAGS+=	-fsanitize=thread
 .endif
 
 KUBSAN_ENABLED!=	grep KUBSAN opt_global.h || true ; echo
 .if !empty(KUBSAN_ENABLED)
 SAN_CFLAGS+=	-fsanitize=undefined
 .endif
 
 COVERAGE_ENABLED!=	grep COVERAGE opt_global.h || true ; echo
 .if !empty(COVERAGE_ENABLED)
 .if ${COMPILER_TYPE} == "clang" || \
     (${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 80100)
 SAN_CFLAGS+=	-fsanitize-coverage=trace-pc,trace-cmp
 .else
 SAN_CFLAGS+=	-fsanitize-coverage=trace-pc
 .endif
 .endif
 
 CFLAGS+=	${SAN_CFLAGS}
 
 GCOV_ENABLED!=	grep GCOV opt_global.h || true ; echo
 .if !empty(GCOV_ENABLED)
 .if ${COMPILER_TYPE} == "gcc"
 GCOV_CFLAGS+=	 -fprofile-arcs -ftest-coverage
 .endif
 .endif
 
 CFLAGS+=	${GCOV_CFLAGS}
 
 # Put configuration-specific C flags last (except for ${PROF}) so that they
 # can override the others.
 CFLAGS+=	${CONF_CFLAGS}
 
 .if defined(LINKER_FEATURES) && ${LINKER_FEATURES:Mbuild-id}
 LDFLAGS+=	--build-id=sha1
 .endif
 
 .if (${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "amd64" || \
     ${MACHINE_CPUARCH} == "i386" || ${MACHINE} == "powerpc") && \
     defined(LINKER_FEATURES) && ${LINKER_FEATURES:Mifunc} == ""
 .error amd64/arm64/i386/ppc* kernel requires linker ifunc support
 .endif
 .if ${MACHINE_CPUARCH} == "amd64"
 LDFLAGS+=	-z max-page-size=2097152
 .if ${LINKER_TYPE} != "lld"
 LDFLAGS+=	-z common-page-size=4096
 .else
 .if defined(LINKER_FEATURES) && !${LINKER_FEATURES:Mifunc-noplt}
 .warning "Linker ${LD} does not support -z ifunc-noplt -> ifunc calls are unoptimized."
 .else
 LDFLAGS+=	-z notext -z ifunc-noplt
 .endif
 .endif
 .endif  # ${MACHINE_CPUARCH} == "amd64"
 
 .if ${MACHINE_CPUARCH} == "riscv"
 # Hack: Work around undefined weak symbols being out of range when linking with
 # LLD (address is a PC-relative calculation, and BFD works around this by
 # rewriting the instructions to generate an absolute address of 0); -fPIE
 # avoids this since it uses the GOT for all extern symbols, which is overly
 # inefficient for us. Drop once undefined weak symbols work with medany.
 .if ${LINKER_TYPE} == "lld"
 CFLAGS+=	-fPIE
 .endif
 .endif
 
 NORMAL_C= ${CC} -c ${CFLAGS} ${WERROR} ${PROF} ${.IMPSRC}
 NORMAL_S= ${CC:N${CCACHE_BIN}} -c ${ASM_CFLAGS} ${WERROR} ${.IMPSRC}
 PROFILE_C= ${CC} -c ${CFLAGS} ${WERROR} ${.IMPSRC}
 NORMAL_C_NOWERROR= ${CC} -c ${CFLAGS} ${PROF} ${.IMPSRC}
 
 NORMAL_M= ${AWK} -f $S/tools/makeobjops.awk ${.IMPSRC} -c ; \
 	  ${CC} -c ${CFLAGS} ${WERROR} ${PROF} ${.PREFIX}.c
 
 NORMAL_FW= uudecode -o ${.TARGET} ${.ALLSRC}
 NORMAL_FWO= ${CC:N${CCACHE_BIN}} -c ${ASM_CFLAGS} ${WERROR} -o ${.TARGET} \
 	$S/kern/firmw.S -DFIRMW_FILE="${.ALLSRC:M*.fw}" \
 	-DFIRMW_SYMBOL="${.ALLSRC:M*.fw:C/[-.\/]/_/g}"
 
 # for ZSTD in the kernel (include zstd/lib/freebsd before other CFLAGS)
 ZSTD_C= ${CC} -c -DZSTD_HEAPMODE=1 -I$S/contrib/zstd/lib/freebsd ${CFLAGS} -I$S/contrib/zstd/lib -I$S/contrib/zstd/lib/common ${WERROR} -Wno-inline -Wno-missing-prototypes ${PROF} -U__BMI__ ${.IMPSRC}
 # https://github.com/facebook/zstd/commit/812e8f2a [zstd 1.4.1]
 # "Note that [GCC] autovectorization still does not do a good job on the
 # optimized version, so it's turned off via attribute and flag.  I found
 # that neither attribute nor command-line flag were entirely successful in
 # turning off vectorization, which is why there were both."
 .if ${COMPILER_TYPE} == "gcc"
 ZSTD_DECOMPRESS_BLOCK_FLAGS= -fno-tree-vectorize
 .endif
 
 ZINCDIR=$S/contrib/openzfs/include
 # Common for dtrace / zfs
 CDDL_CFLAGS=	\
 	-DFREEBSD_NAMECACHE \
 	-D_SYS_VMEM_H_ \
 	-D__KERNEL \
 	-D__KERNEL__ \
 	-nostdinc \
 	-include $S/modules/zfs/static_ccompile.h \
 	-I${ZINCDIR} \
-	-I${ZINCDIR}/spl \
 	-I${ZINCDIR}/os/freebsd \
 	-I${ZINCDIR}/os/freebsd/spl \
 	-I${ZINCDIR}/os/freebsd/zfs  \
 	-I$S/modules/zfs \
 	-I$S/contrib/openzfs/module/zstd/include \
-	-I$S/contrib/openzfs/module/zstd/lib/freebsd/ \
 	${CFLAGS} \
-	-Wno-unknown-pragmas \
-	-Wno-missing-prototypes \
-	-Wno-undef \
-	-Wno-strict-prototypes \
 	-Wno-cast-qual \
+	-Wno-duplicate-decl-specifier \
+	-Wno-inline \
+	-Wno-missing-braces \
+	-Wno-missing-prototypes \
+	-Wno-nested-externs \
 	-Wno-parentheses \
+	-Wno-pointer-arith \
 	-Wno-redundant-decls \
-	-Wno-missing-braces \
-	-Wno-uninitialized \
-	-Wno-unused \
-	-Wno-inline \
+	-Wno-strict-prototypes \
 	-Wno-switch \
-	-Wno-pointer-arith \
+	-Wno-undef \
+	-Wno-uninitialized \
 	-Wno-unknown-pragmas \
-	-Wno-duplicate-decl-specifier \
+	-Wno-unused \
 	-include ${ZINCDIR}/os/freebsd/spl/sys/ccompile.h \
 	-I$S/cddl/contrib/opensolaris/uts/common \
 	-I$S -I$S/cddl/compat/opensolaris
 CDDL_C=		${CC} -c ${CDDL_CFLAGS} ${WERROR} ${PROF} ${.IMPSRC}
 
 # Special flags for managing the compat compiles for ZFS
 ZFS_CFLAGS+=	${CDDL_CFLAGS} -DBUILDING_ZFS -DHAVE_UIO_ZEROCOPY \
 	-DWITH_NETDUMP -D__KERNEL__ -D_SYS_CONDVAR_H_ -DSMP \
 	-DIN_FREEBSD_BASE -DHAVE_KSID
 
 .if ${MACHINE_ARCH} == "amd64"
 ZFS_CFLAGS+= -DHAVE_AVX2 -DHAVE_AVX -D__x86_64 -DHAVE_SSE2 -DHAVE_AVX512F \
 	-DHAVE_SSSE3 -DHAVE_AVX512BW
 .endif
 
 .if ${MACHINE_ARCH} == "i386" || ${MACHINE_ARCH} == "powerpc" || \
 	${MACHINE_ARCH} == "powerpcspe" || ${MACHINE_ARCH} == "arm"
 ZFS_CFLAGS+= -DBITS_PER_LONG=32
 .else
 ZFS_CFLAGS+= -DBITS_PER_LONG=64
 .endif
 
 
 ZFS_ASM_CFLAGS= -x assembler-with-cpp -DLOCORE ${ZFS_CFLAGS}
 ZFS_C=		${CC} -c ${ZFS_CFLAGS} ${WERROR} ${PROF} ${.IMPSRC}
 ZFS_RPC_C=	${CC} -c ${ZFS_CFLAGS} -DHAVE_RPC_TYPES ${WERROR} ${PROF} ${.IMPSRC}
 ZFS_S=		${CC} -c ${ZFS_ASM_CFLAGS} ${WERROR} ${.IMPSRC}
 
 
 
 # Special flags for managing the compat compiles for DTrace
 DTRACE_CFLAGS=	-DBUILDING_DTRACE ${CDDL_CFLAGS} -I$S/cddl/dev/dtrace -I$S/cddl/dev/dtrace/${MACHINE_CPUARCH}
 .if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386"
 DTRACE_CFLAGS+=	-I$S/cddl/contrib/opensolaris/uts/intel -I$S/cddl/dev/dtrace/x86
 .endif
 DTRACE_CFLAGS+=	-I$S/cddl/contrib/opensolaris/common/util -I$S -DDIS_MEM -DSMP -I$S/cddl/compat/opensolaris
 DTRACE_CFLAGS+=	-I$S/cddl/contrib/opensolaris/uts/common
 DTRACE_ASM_CFLAGS=	-x assembler-with-cpp -DLOCORE ${DTRACE_CFLAGS}
 DTRACE_C=	${CC} -c ${DTRACE_CFLAGS}	${WERROR} ${PROF} ${.IMPSRC}
 DTRACE_S=	${CC} -c ${DTRACE_ASM_CFLAGS}	${WERROR} ${.IMPSRC}
 
 # Special flags for managing the compat compiles for DTrace/FBT
 FBT_CFLAGS=	-DBUILDING_DTRACE -nostdinc -I$S/cddl/dev/fbt/${MACHINE_CPUARCH} -I$S/cddl/dev/fbt ${CDDL_CFLAGS} -I$S/cddl/compat/opensolaris -I$S/cddl/contrib/opensolaris/uts/common  
 .if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386"
 FBT_CFLAGS+=	-I$S/cddl/dev/fbt/x86
 .endif
 FBT_C=		${CC} -c ${FBT_CFLAGS}		${WERROR} ${PROF} ${.IMPSRC}
 
 .if ${MK_CTF} != "no"
 NORMAL_CTFCONVERT=	${CTFCONVERT} ${CTFFLAGS} ${.TARGET}
 .elif ${MAKE_VERSION} >= 5201111300
 NORMAL_CTFCONVERT=
 .else
 NORMAL_CTFCONVERT=	@:
 .endif
 
 # Linux Kernel Programming Interface C-flags
 LINUXKPI_INCLUDES=	-I$S/compat/linuxkpi/common/include
 LINUXKPI_C=		${NORMAL_C} ${LINUXKPI_INCLUDES}
 
 # Infiniband C flags.  Correct include paths and omit errors that linux
 # does not honor.
 OFEDINCLUDES=	-I$S/ofed/include -I$S/ofed/include/uapi ${LINUXKPI_INCLUDES}
 OFEDNOERR=	-Wno-cast-qual -Wno-pointer-arith
 OFEDCFLAGS=	${CFLAGS:N-I*} -DCONFIG_INFINIBAND_USER_MEM \
 		${OFEDINCLUDES} ${CFLAGS:M-I*} ${OFEDNOERR}
 OFED_C_NOIMP=	${CC} -c -o ${.TARGET} ${OFEDCFLAGS} ${WERROR} ${PROF}
 OFED_C=		${OFED_C_NOIMP} ${.IMPSRC}
 
 # mlxfw C flags.
 MLXFW_C=	${OFED_C_NOIMP} \
 		-I${SRCTOP}/sys/contrib/xz-embedded/freebsd \
 		-I${SRCTOP}/sys/contrib/xz-embedded/linux/lib/xz \
 		${.IMPSRC}
 
 GEN_CFILES= $S/$M/$M/genassym.c ${MFILES:T:S/.m$/.c/}
 SYSTEM_CFILES= config.c env.c hints.c vnode_if.c
 SYSTEM_DEP= Makefile ${SYSTEM_OBJS}
 SYSTEM_OBJS= locore.o ${MDOBJS} ${OBJS}
 SYSTEM_OBJS+= ${SYSTEM_CFILES:.c=.o}
 SYSTEM_OBJS+= hack.pico
 
 KEYMAP=kbdcontrol -P ${SRCTOP}/share/vt/keymaps -P ${SRCTOP}/share/syscons/keymaps
 KEYMAP_FIX=sed -e 's/^static keymap_t.* = /static keymap_t key_map = /' -e 's/^static accentmap_t.* = /static accentmap_t accent_map = /'
 
 MD_ROOT_SIZE_CONFIGURED!=	grep MD_ROOT_SIZE opt_md.h || true ; echo
 .if ${MFS_IMAGE:Uno} != "no"
 .if empty(MD_ROOT_SIZE_CONFIGURED)
 SYSTEM_OBJS+= embedfs_${MFS_IMAGE:T:R}.o
 .endif
 .endif
 SYSTEM_LD_BASECMD= \
 	${LD} -m ${LD_EMULATION} -Bdynamic -T ${LDSCRIPT} ${_LDFLAGS} \
 	--no-warn-mismatch --warn-common --export-dynamic \
 	--dynamic-linker /red/herring -X
 SYSTEM_LD= @${SYSTEM_LD_BASECMD} -o ${.TARGET} ${SYSTEM_OBJS} vers.o
 SYSTEM_LD_TAIL= @${OBJCOPY} --strip-symbol gcc2_compiled. ${.TARGET} ; \
 	${SIZE} ${.TARGET} ; chmod 755 ${.TARGET}
 SYSTEM_DEP+= ${LDSCRIPT}
 
 # Calculate path for .m files early, if needed.
 .if !defined(NO_MODULES) && !defined(__MPATH) && !make(install) && \
     (empty(.MAKEFLAGS:M-V) || defined(NO_SKIP_MPATH))
 __MPATH!=find ${S:tA}/ -name \*_if.m
 .endif
 
 # MKMODULESENV is set here so that port makefiles can augment
 # them.
 
 MKMODULESENV+=	MAKEOBJDIRPREFIX=${.OBJDIR}/modules KMODDIR=${KODIR}
 MKMODULESENV+=	MACHINE_CPUARCH=${MACHINE_CPUARCH}
 MKMODULESENV+=	MACHINE=${MACHINE} MACHINE_ARCH=${MACHINE_ARCH}
 MKMODULESENV+=	MODULES_EXTRA="${MODULES_EXTRA}" WITHOUT_MODULES="${WITHOUT_MODULES}"
 MKMODULESENV+=	ARCH_FLAGS="${ARCH_FLAGS}"
 .if (${KERN_IDENT} == LINT)
 MKMODULESENV+=	ALL_MODULES=LINT
 .endif
 .if defined(MODULES_OVERRIDE)
 MKMODULESENV+=	MODULES_OVERRIDE="${MODULES_OVERRIDE}"
 .endif
 .if defined(DEBUG)
 MKMODULESENV+=	DEBUG_FLAGS="${DEBUG}"
 .endif
 .if !defined(NO_MODULES)
 MKMODULESENV+=	__MPATH="${__MPATH}"
 .endif
 
 # Detect kernel config options that force stack frames to be turned on.
 DDB_ENABLED!=	grep DDB opt_ddb.h || true ; echo
 DTR_ENABLED!=	grep KDTRACE_FRAME opt_kdtrace.h || true ; echo
 HWPMC_ENABLED!=	grep HWPMC opt_hwpmc_hooks.h || true ; echo