Index: sys/amd64/amd64/minidump_machdep.c
===================================================================
--- sys/amd64/amd64/minidump_machdep.c
+++ sys/amd64/amd64/minidump_machdep.c
@@ -172,6 +172,7 @@
 	int ii, j, k, n;
 	int retry_count;
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 
 	retry_count = 0;
  retry:
@@ -253,8 +254,9 @@
 	}
 
 	/* Calculate dump size. */
+	mbp = state->msgbufp;
 	dumpsize = pmapsize;
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	VM_PAGE_DUMP_FOREACH(pa) {
@@ -274,7 +276,7 @@
 	bzero(&mdhdr, sizeof(mdhdr));
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.pmapsize = pmapsize;
 	mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
@@ -300,7 +302,8 @@
 		goto fail;
 
 	/* Dump msgbuf up front */
-	error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size));
+	error = blk_write(di, (char *)mbp->msg_ptr, 0,
+	    round_page(mbp->msg_size));
 	if (error)
 		goto fail;
 
Index: sys/arm/arm/minidump_machdep.c
===================================================================
--- sys/arm/arm/minidump_machdep.c
+++ sys/arm/arm/minidump_machdep.c
@@ -156,6 +156,7 @@
 cpu_minidumpsys(struct dumperinfo *di, struct minidumpstate *state)
 {
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 	uint64_t dumpsize, *dump_avail_buf;
 	uint32_t ptesize;
 	uint32_t pa, prev_pa = 0, count = 0;
@@ -190,8 +191,9 @@
 	}
 
 	/* Calculate dump size. */
+	mbp = state->msgbufp;
 	dumpsize = ptesize;
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(nitems(dump_avail) * sizeof(uint64_t));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	VM_PAGE_DUMP_FOREACH(pa) {
@@ -209,7 +211,7 @@
 	bzero(&mdhdr, sizeof(mdhdr));
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.ptesize = ptesize;
 	mdhdr.kernbase = KERNBASE;
@@ -235,8 +237,8 @@
 		goto fail;
 
 	/* Dump msgbuf up front */
-	error = blk_write(di, (char *)msgbufp->msg_ptr, 0,
-	    round_page(msgbufp->msg_size));
+	error = blk_write(di, (char *)mbp->msg_ptr, 0,
+	    round_page(mbp->msg_size));
 	if (error)
 		goto fail;
 
Index: sys/arm64/arm64/minidump_machdep.c
===================================================================
--- sys/arm64/arm64/minidump_machdep.c
+++ sys/arm64/arm64/minidump_machdep.c
@@ -150,6 +150,7 @@
 cpu_minidumpsys(struct dumperinfo *di, struct minidumpstate *state)
 {
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 	pd_entry_t *l0, *l1, l1e, *l2, l2e;
 	pt_entry_t *l3, l3e;
 	vm_offset_t va, kva_end;
@@ -207,8 +208,9 @@
 	}
 
 	/* Calculate dump size. */
+	mbp = state->msgbufp;
 	dumpsize = pmapsize;
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	VM_PAGE_DUMP_FOREACH(pa) {
@@ -225,7 +227,7 @@
 	bzero(&mdhdr, sizeof(mdhdr));
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.pmapsize = pmapsize;
 	mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
@@ -252,8 +254,8 @@
 		goto fail;
 
 	/* Dump msgbuf up front */
-	error = blk_write(di, (char *)msgbufp->msg_ptr, 0,
-	    round_page(msgbufp->msg_size));
+	error = blk_write(di, (char *)mbp->msg_ptr, 0,
+	    round_page(mbp->msg_size));
 	if (error)
 		goto fail;
 
Index: sys/i386/i386/minidump_machdep_base.c
===================================================================
--- sys/i386/i386/minidump_machdep_base.c
+++ sys/i386/i386/minidump_machdep_base.c
@@ -164,6 +164,7 @@
 	pt_entry_t *pt, pte;
 	int j, k;
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 
 	/* Snapshot the KVA upper bound in case it grows. */
 	kva_end = kernel_vm_end;
@@ -212,8 +213,9 @@
 	}
 
 	/* Calculate dump size. */
+	mbp = state->msgbufp;
 	dumpsize = ptesize;
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	VM_PAGE_DUMP_FOREACH(pa) {
@@ -232,7 +234,7 @@
 	bzero(&mdhdr, sizeof(mdhdr));
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.ptesize = ptesize;
 	mdhdr.kernbase = KERNBASE;
@@ -257,7 +259,8 @@
 		goto fail;
 
 	/* Dump msgbuf up front */
-	error = blk_write(di, (char *)msgbufp->msg_ptr, 0, round_page(msgbufp->msg_size));
+	error = blk_write(di, (char *)mbp->msg_ptr, 0,
+	    round_page(mbp->msg_size));
 	if (error)
 		goto fail;
 
Index: sys/mips/mips/minidump_machdep.c
===================================================================
--- sys/mips/mips/minidump_machdep.c
+++ sys/mips/mips/minidump_machdep.c
@@ -109,6 +109,7 @@
 cpu_minidumpsys(struct dumperinfo *di, struct minidumpstate *state)
 {
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 	uint64_t *dump_avail_buf;
 	uint32_t ptesize;
 	vm_paddr_t pa;
@@ -148,8 +149,9 @@
 	}
 
 	/* Calculate dump size. */
+	mbp = state->msgbufp;
 	dumpsize = ptesize;
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(nitems(dump_avail) * sizeof(uint64_t));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	VM_PAGE_DUMP_FOREACH(pa) {
@@ -167,7 +169,7 @@
 	bzero(&mdhdr, sizeof(mdhdr));
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.ptesize = ptesize;
 	mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
@@ -191,8 +193,8 @@
 		goto fail;
 
 	/* Dump msgbuf up front */
-	error = write_buffer(di, (char *)msgbufp->msg_ptr, 
-	    round_page(msgbufp->msg_size));
+	error = write_buffer(di, (char *)mbp->msg_ptr,
+	    round_page(mbp->msg_size));
 	if (error)
 		goto fail;
 
Index: sys/powerpc/powerpc/minidump_machdep.c
===================================================================
--- sys/powerpc/powerpc/minidump_machdep.c
+++ sys/powerpc/powerpc/minidump_machdep.c
@@ -195,6 +195,7 @@
 	int error, retry_count;
 	uint32_t pmapsize;
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 
 	retry_count = 0;
 retry:
@@ -210,8 +211,9 @@
 	}
 
 	/* Calculate dump size */
+	mbp = state->msgbufp;
 	dumpsize = PAGE_SIZE;				/* header */
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	dumpsize += pmapsize;
@@ -229,7 +231,7 @@
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	strncpy(mdhdr.mmu_name, pmap_mmu_name(), sizeof(mdhdr.mmu_name) - 1);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.pmapsize = pmapsize;
 	mdhdr.kernbase = VM_MIN_KERNEL_ADDRESS;
@@ -260,9 +262,9 @@
 	dump_total("header", PAGE_SIZE);
 
 	/* Dump msgbuf up front */
-	error = blk_write(di, (char *)msgbufp->msg_ptr, 0,
-	    round_page(msgbufp->msg_size));
-	dump_total("msgbuf", round_page(msgbufp->msg_size));
+	error = blk_write(di, (char *)mbp->msg_ptr, 0,
+	    round_page(mbp->msg_size));
+	dump_total("msgbuf", round_page(mbp->msg_size));
 
 	/* Dump dump_avail */
 	_Static_assert(sizeof(dump_avail) <= sizeof(pgbuf),
Index: sys/riscv/riscv/minidump_machdep.c
===================================================================
--- sys/riscv/riscv/minidump_machdep.c
+++ sys/riscv/riscv/minidump_machdep.c
@@ -158,6 +158,7 @@
 	pd_entry_t *l1, *l2, l2e;
 	pt_entry_t *l3, l3e;
 	struct minidumphdr mdhdr;
+	struct msgbuf *mbp;
 	uint32_t pmapsize;
 	vm_offset_t va;
 	vm_paddr_t pa;
@@ -211,8 +212,9 @@
 	}
 
 	/* Calculate dump size */
+	mbp = state->msgbufp;
 	dumpsize = pmapsize;
-	dumpsize += round_page(msgbufp->msg_size);
+	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	VM_PAGE_DUMP_FOREACH(pa) {
@@ -230,7 +232,7 @@
 	bzero(&mdhdr, sizeof(mdhdr));
 	strcpy(mdhdr.magic, MINIDUMP_MAGIC);
 	mdhdr.version = MINIDUMP_VERSION;
-	mdhdr.msgbufsize = msgbufp->msg_size;
+	mdhdr.msgbufsize = mbp->msg_size;
 	mdhdr.bitmapsize = round_page(BITSET_SIZE(vm_page_dump_pages));
 	mdhdr.pmapsize = pmapsize;
 	mdhdr.kernbase = KERNBASE;
@@ -257,8 +259,8 @@
 		goto fail;
 
 	/* Dump msgbuf up front */
-	error = blk_write(di, (char *)msgbufp->msg_ptr, 0,
-	    round_page(msgbufp->msg_size));
+	error = blk_write(di, (char *)mbp->msg_ptr, 0,
+	    round_page(mbp->msg_size));
 	if (error)
 		goto fail;