Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

17 files changed, 704 insertions, 0 deletions

diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
new file mode 100644
index 000000000..e0b8ec9a9
--- /dev/null
+++ b/arch/mips/boot/compressed/Makefile
@@ -0,0 +1,213 @@
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.
+#
+# Adapted for MIPS Pete Popov, Dan Malek
+#
+# Copyright (C) 1994 by Linus Torvalds
+# Adapted for PowerPC by Gary Thomas
+# modified by Cort (cort@cs.nmt.edu)
+#
+# Copyright (C) 2009 Lemote Inc. & DSLab, Lanzhou University
+# Author: Wu Zhangjin <wuzhangjin@gmail.com>
+#
+
+include $(srctree)/arch/mips/Kbuild.platforms
+
+# set the default size of the mallocing area for decompressing
+BOOT_HEAP_SIZE := 0x400000
+
+# Disable Function Tracer
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE), $(KBUILD_CFLAGS))
+
+KBUILD_CFLAGS := $(filter-out -fstack-protector, $(KBUILD_CFLAGS))
+
+# Disable lq/sq in zboot
+ifdef CONFIG_CPU_LOONGSON64
+KBUILD_CFLAGS := $(filter-out -march=loongson3a, $(KBUILD_CFLAGS)) -march=mips64r2
+endif
+
+KBUILD_CFLAGS := $(KBUILD_CFLAGS) -D__KERNEL__ -D__DISABLE_EXPORTS \
+	-DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) -D"VMLINUX_LOAD_ADDRESS_ULL=$(VMLINUX_LOAD_ADDRESS)ull"
+
+KBUILD_AFLAGS := $(KBUILD_AFLAGS) -D__ASSEMBLY__ \
+	-DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) \
+	-DKERNEL_ENTRY=$(VMLINUX_ENTRY_ADDRESS)
+
+# decompressor objects (linked with vmlinuz)
+vmlinuzobjs-y := $(obj)/head.o $(obj)/decompress.o $(obj)/string.o $(obj)/bswapsi.o
+
+ifdef CONFIG_DEBUG_ZBOOT
+vmlinuzobjs-$(CONFIG_DEBUG_ZBOOT)		   += $(obj)/dbg.o
+vmlinuzobjs-$(CONFIG_SYS_SUPPORTS_ZBOOT_UART16550) += $(obj)/uart-16550.o
+vmlinuzobjs-$(CONFIG_SYS_SUPPORTS_ZBOOT_UART_PROM) += $(obj)/uart-prom.o
+vmlinuzobjs-$(CONFIG_MIPS_ALCHEMY)		   += $(obj)/uart-alchemy.o
+vmlinuzobjs-$(CONFIG_ATH79)			   += $(obj)/uart-ath79.o
+endif
+
+vmlinuzobjs-$(CONFIG_KERNEL_XZ) += $(obj)/ashldi3.o
+
+vmlinuzobjs-$(CONFIG_KERNEL_ZSTD) += $(obj)/bswapdi.o $(obj)/ashldi3.o $(obj)/clz_ctz.o
+
+targets := $(notdir $(vmlinuzobjs-y))
+
+targets += vmlinux.bin
+
+OBJCOPYFLAGS_vmlinux.bin := $(OBJCOPYFLAGS) -O binary -R .comment -S
+
+$(obj)/vmlinux.bin: $(KBUILD_IMAGE) FORCE
+	$(call if_changed,objcopy)
+
+tool_$(CONFIG_KERNEL_GZIP)    = gzip
+tool_$(CONFIG_KERNEL_BZIP2)   = bzip2_with_size
+tool_$(CONFIG_KERNEL_LZ4)     = lz4_with_size
+tool_$(CONFIG_KERNEL_LZMA)    = lzma_with_size
+tool_$(CONFIG_KERNEL_LZO)     = lzo_with_size
+tool_$(CONFIG_KERNEL_XZ)      = xzkern_with_size
+tool_$(CONFIG_KERNEL_ZSTD)    = zstd22_with_size
+
+targets += vmlinux.bin.z
+
+$(obj)/vmlinux.bin.z: $(obj)/vmlinux.bin FORCE
+	$(call if_changed,$(tool_y))
+
+targets += piggy.o dummy.o
+
+OBJCOPYFLAGS_piggy.o := --add-section=.image=$(obj)/vmlinux.bin.z \
+			--set-section-flags=.image=contents,alloc,load,readonly,data
+
+$(obj)/piggy.o: $(obj)/dummy.o $(obj)/vmlinux.bin.z FORCE
+	$(call if_changed,objcopy)
+
+HOSTCFLAGS_calc_vmlinuz_load_addr.o += $(LINUXINCLUDE)
+
+# Calculate the load address of the compressed kernel image
+hostprogs := calc_vmlinuz_load_addr
+
+ifneq (0x0,$(CONFIG_ZBOOT_LOAD_ADDRESS))
+zload-y	= $(CONFIG_ZBOOT_LOAD_ADDRESS)
+endif
+
+ifneq ($(zload-y),)
+VMLINUZ_LOAD_ADDRESS := $(zload-y)
+else
+VMLINUZ_LOAD_ADDRESS = $(shell $(obj)/calc_vmlinuz_load_addr \
+		$(obj)/vmlinux.bin $(LINKER_LOAD_ADDRESS))
+endif
+UIMAGE_LOADADDR = $(VMLINUZ_LOAD_ADDRESS)
+
+vmlinuzobjs-y += $(obj)/piggy.o
+
+targets += ../../../../vmlinuz
+
+quiet_cmd_zld = LD      $@
+      cmd_zld = $(LD) $(KBUILD_LDFLAGS) -Ttext $(VMLINUZ_LOAD_ADDRESS) -T $< $(vmlinuzobjs-y) -o $@
+quiet_cmd_strip = STRIP   $@
+      cmd_strip = $(STRIP) -s $@
+
+$(objtree)/vmlinuz: $(src)/ld.script $(vmlinuzobjs-y) $(obj)/calc_vmlinuz_load_addr
+	$(call cmd,zld)
+	$(call cmd,strip)
+
+objboot := $(objtree)/arch/mips/boot
+
+$(objboot)/vmlinuz: $(objtree)/vmlinuz FORCE
+
+#
+# Some DECstations need all possible sections of an ECOFF executable
+#
+ifdef CONFIG_MACH_DECSTATION
+  e2eflag := -a
+endif
+
+# elf2ecoff can only handle 32bit image
+hostprogs += ../elf2ecoff
+
+ifdef CONFIG_32BIT
+	VMLINUZ = $(objtree)/vmlinuz
+else
+	VMLINUZ = $(objboot)/vmlinuz.32
+endif
+
+targets += ../vmlinuz.32
+
+quiet_cmd_32 = OBJCOPY $@
+      cmd_32 = $(OBJCOPY) -O $(32bit-bfd) $(OBJCOPYFLAGS) $< $@
+
+$(objboot)/vmlinuz.32: $(objtree)/vmlinuz
+	$(call cmd,32)
+
+targets += ../vmlinuz.ecoff
+
+quiet_cmd_ecoff = ECOFF	  $@
+      cmd_ecoff = $< $(VMLINUZ) $@ $(e2eflag)
+
+$(objboot)/vmlinuz.ecoff: $(objboot)/elf2ecoff $(VMLINUZ)
+	$(call cmd,ecoff)
+
+targets += ../vmlinuz.bin
+
+OBJCOPYFLAGS_vmlinuz.bin := $(OBJCOPYFLAGS) -O binary
+
+$(objboot)/vmlinuz.bin: $(objtree)/vmlinuz
+	$(call cmd,objcopy)
+
+targets += ../vmlinuz.srec
+
+OBJCOPYFLAGS_vmlinuz.srec := $(OBJCOPYFLAGS) -S -O srec
+
+$(objboot)/vmlinuz.srec: $(objtree)/vmlinuz
+	$(call cmd,objcopy)
+
+targets += ../uzImage.bin
+
+$(objboot)/uzImage.bin: $(objboot)/vmlinuz.bin FORCE
+	$(call if_changed,uimage,none)
+
+#
+# Flattened Image Tree (.itb) image
+#
+
+ifeq ($(ADDR_BITS),32)
+itb_addr_cells = 1
+endif
+ifeq ($(ADDR_BITS),64)
+itb_addr_cells = 2
+endif
+
+targets += ../vmlinuz.its.S
+
+quiet_cmd_its_cat = CAT     $@
+      cmd_its_cat = cat $(real-prereqs) >$@
+
+$(objboot)/vmlinuz.its.S: $(addprefix $(srctree)/arch/mips/$(PLATFORM)/,$(ITS_INPUTS)) FORCE
+	$(call if_changed,its_cat)
+
+targets += ../vmlinuz.its
+
+quiet_cmd_cpp_its_S = ITS     $@
+      cmd_cpp_its_S = $(CPP) -P -C -o $@ $< \
+		        -DKERNEL_NAME="\"Linux $(KERNELRELEASE)\"" \
+			-DVMLINUX_BINARY="\"$(2)\"" \
+			-DVMLINUX_COMPRESSION="\"none\"" \
+			-DVMLINUX_LOAD_ADDRESS=$(VMLINUZ_LOAD_ADDRESS) \
+			-DVMLINUX_ENTRY_ADDRESS=$(VMLINUZ_LOAD_ADDRESS) \
+			-DADDR_BITS=$(ADDR_BITS) \
+			-DADDR_CELLS=$(itb_addr_cells)
+
+$(objboot)/vmlinuz.its: $(objboot)/vmlinuz.its.S FORCE
+	$(call if_changed,cpp_its_S,vmlinuz.bin)
+
+targets += ../vmlinuz.itb
+
+quiet_cmd_itb-image = ITB     $@
+      cmd_itb-image = \
+		env PATH="$(objtree)/scripts/dtc:$(PATH)" \
+		$(BASH) $(MKIMAGE) \
+		-D "-I dts -O dtb -p 500 \
+			--include $(objtree)/arch/mips \
+			--warning no-unit_address_vs_reg" \
+		-f $(2) $@
+
+$(objboot)/vmlinuz.itb: $(objboot)/vmlinuz.its $(objboot)/vmlinuz.bin FORCE
+	$(call if_changed,itb-image,$<)
diff --git a/arch/mips/boot/compressed/ashldi3.c b/arch/mips/boot/compressed/ashldi3.c
new file mode 100644
index 000000000..f7bf6a7aa
--- /dev/null
+++ b/arch/mips/boot/compressed/ashldi3.c
@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "../../../../lib/ashldi3.c"
diff --git a/arch/mips/boot/compressed/bswapdi.c b/arch/mips/boot/compressed/bswapdi.c
new file mode 100644
index 000000000..acb28aebb
--- /dev/null
+++ b/arch/mips/boot/compressed/bswapdi.c
@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "../../lib/bswapdi.c"
diff --git a/arch/mips/boot/compressed/bswapsi.c b/arch/mips/boot/compressed/bswapsi.c
new file mode 100644
index 000000000..fdb9c6476
--- /dev/null
+++ b/arch/mips/boot/compressed/bswapsi.c
@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "../../lib/bswapsi.c"
diff --git a/arch/mips/boot/compressed/calc_vmlinuz_load_addr.c b/arch/mips/boot/compressed/calc_vmlinuz_load_addr.c
new file mode 100644
index 000000000..080b926d2
--- /dev/null
+++ b/arch/mips/boot/compressed/calc_vmlinuz_load_addr.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2010 "Wu Zhangjin" <wuzhangjin@gmail.com>
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <linux/sizes.h>
+
+int main(int argc, char *argv[])
+{
+	unsigned long long vmlinux_size, vmlinux_load_addr, vmlinuz_load_addr;
+	struct stat sb;
+
+	if (argc != 3) {
+		fprintf(stderr, "Usage: %s <pathname> <vmlinux_load_addr>\n",
+				argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	if (stat(argv[1], &sb) == -1) {
+		perror("stat");
+		return EXIT_FAILURE;
+	}
+
+	/* Convert hex characters to dec number */
+	errno = 0;
+	if (sscanf(argv[2], "%llx", &vmlinux_load_addr) != 1) {
+		if (errno != 0)
+			perror("sscanf");
+		else
+			fprintf(stderr, "No matching characters\n");
+
+		return EXIT_FAILURE;
+	}
+
+	vmlinux_size = (uint64_t)sb.st_size;
+	vmlinuz_load_addr = vmlinux_load_addr + vmlinux_size;
+
+	/*
+	 * Align with 64KB: KEXEC needs load sections to be aligned to PAGE_SIZE,
+	 * which may be as large as 64KB depending on the kernel configuration.
+	 */
+
+	vmlinuz_load_addr += (SZ_64K - vmlinux_size % SZ_64K);
+
+	printf("0x%llx\n", vmlinuz_load_addr);
+
+	return EXIT_SUCCESS;
+}
diff --git a/arch/mips/boot/compressed/clz_ctz.c b/arch/mips/boot/compressed/clz_ctz.c
new file mode 100644
index 000000000..b4a1b6eb2
--- /dev/null
+++ b/arch/mips/boot/compressed/clz_ctz.c
@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "../../../../lib/clz_ctz.c"
diff --git a/arch/mips/boot/compressed/dbg.c b/arch/mips/boot/compressed/dbg.c
new file mode 100644
index 000000000..95405292a
--- /dev/null
+++ b/arch/mips/boot/compressed/dbg.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MIPS-specific debug support for pre-boot environment
+ *
+ * NOTE: putc() is board specific, if your board have a 16550 compatible uart,
+ * please select SYS_SUPPORTS_ZBOOT_UART16550 for your machine. otherwise, you
+ * need to implement your own putc().
+ */
+#include <linux/compiler.h>
+#include <linux/types.h>
+
+#include "decompress.h"
+
+void __weak putc(char c)
+{
+}
+
+void puts(const char *s)
+{
+	char c;
+	while ((c = *s++) != '\0') {
+		putc(c);
+		if (c == '\n')
+			putc('\r');
+	}
+}
+
+void puthex(unsigned long long val)
+{
+
+	unsigned char buf[10];
+	int i;
+	for (i = 7; i >= 0; i--) {
+		buf[i] = "0123456789ABCDEF"[val & 0x0F];
+		val >>= 4;
+	}
+	buf[8] = '\0';
+	puts(buf);
+}
diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
new file mode 100644
index 000000000..90021c6a8
--- /dev/null
+++ b/arch/mips/boot/compressed/decompress.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2001 MontaVista Software Inc.
+ * Author: Matt Porter <mporter@mvista.com>
+ *
+ * Copyright (C) 2009 Lemote, Inc.
+ * Author: Wu Zhangjin <wuzhangjin@gmail.com>
+ */
+
+#define DISABLE_BRANCH_PROFILING
+
+#define __NO_FORTIFY
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/libfdt.h>
+
+#include <asm/addrspace.h>
+#include <linux/unaligned.h>
+#include <asm-generic/vmlinux.lds.h>
+
+#include "decompress.h"
+
+/*
+ * These two variables specify the free mem region
+ * that can be used for temporary malloc area
+ */
+unsigned long free_mem_ptr;
+unsigned long free_mem_end_ptr;
+
+void error(char *x)
+{
+	puts("\n\n");
+	puts(x);
+	puts("\n\n -- System halted");
+
+	while (1)
+		;	/* Halt */
+}
+
+/* activate the code for pre-boot environment */
+#define STATIC static
+
+#ifdef CONFIG_KERNEL_GZIP
+#include "../../../../lib/decompress_inflate.c"
+#endif
+
+#ifdef CONFIG_KERNEL_BZIP2
+#include "../../../../lib/decompress_bunzip2.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZ4
+#include "../../../../lib/decompress_unlz4.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZMA
+#include "../../../../lib/decompress_unlzma.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZO
+#include "../../../../lib/decompress_unlzo.c"
+#endif
+
+#ifdef CONFIG_KERNEL_XZ
+#include "../../../../lib/decompress_unxz.c"
+#endif
+
+#ifdef CONFIG_KERNEL_ZSTD
+#include "../../../../lib/decompress_unzstd.c"
+#endif
+
+const unsigned long __stack_chk_guard = 0x000a0dff;
+
+void __stack_chk_fail(void)
+{
+	error("stack-protector: Kernel stack is corrupted\n");
+}
+
+void decompress_kernel(unsigned long boot_heap_start)
+{
+	unsigned long zimage_start, zimage_size;
+
+	zimage_start = (unsigned long)(__image_begin);
+	zimage_size = (unsigned long)(__image_end) -
+	    (unsigned long)(__image_begin);
+
+	puts("zimage at:     ");
+	puthex(zimage_start);
+	puts(" ");
+	puthex(zimage_size + zimage_start);
+	puts("\n");
+
+	/* This area are prepared for mallocing when decompressing */
+	free_mem_ptr = boot_heap_start;
+	free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
+
+	/* Display standard Linux/MIPS boot prompt */
+	puts("Uncompressing Linux at load address ");
+	puthex(VMLINUX_LOAD_ADDRESS_ULL);
+	puts("\n");
+
+	/* Decompress the kernel with according algorithm */
+	__decompress((char *)zimage_start, zimage_size, 0, 0,
+		   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
+
+	if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
+	    fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
+		unsigned int image_size, dtb_size;
+
+		dtb_size = fdt_totalsize((void *)&__appended_dtb);
+
+		/* last four bytes is always image size in little endian */
+		image_size = get_unaligned_le32((void *)__image_end - 4);
+
+		/* The device tree's address must be properly aligned  */
+		image_size = ALIGN(image_size, STRUCT_ALIGNMENT);
+
+		puts("Copy device tree to address  ");
+		puthex(VMLINUX_LOAD_ADDRESS_ULL + image_size);
+		puts("\n");
+
+		/* copy dtb to where the booted kernel will expect it */
+		memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
+		       __appended_dtb, dtb_size);
+	}
+
+	/* FIXME: should we flush cache here? */
+	puts("Now, booting the kernel...\n");
+}
diff --git a/arch/mips/boot/compressed/decompress.h b/arch/mips/boot/compressed/decompress.h
new file mode 100644
index 000000000..073b64593
--- /dev/null
+++ b/arch/mips/boot/compressed/decompress.h
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef _DECOMPRESSOR_H
+#define _DECOMPRESSOR_H
+
+/* The linker tells us where the image is. */
+extern unsigned char __image_begin[], __image_end[];
+
+/* debug interfaces  */
+#ifdef CONFIG_DEBUG_ZBOOT
+extern void putc(char c);
+extern void puts(const char *s);
+extern void puthex(unsigned long long val);
+#else
+#define putc(s) do {} while (0)
+#define puts(s) do {} while (0)
+#define puthex(val) do {} while (0)
+#endif
+
+extern char __appended_dtb[];
+
+void error(char *x);
+void decompress_kernel(unsigned long boot_heap_start);
+
+#endif
diff --git a/arch/mips/boot/compressed/dummy.c b/arch/mips/boot/compressed/dummy.c
new file mode 100644
index 000000000..31dbf45bf
--- /dev/null
+++ b/arch/mips/boot/compressed/dummy.c
@@ -0,0 +1,4 @@
+int main(void)
+{
+	return 0;
+}
diff --git a/arch/mips/boot/compressed/head.S b/arch/mips/boot/compressed/head.S
new file mode 100644
index 000000000..d237a834b
--- /dev/null
+++ b/arch/mips/boot/compressed/head.S
@@ -0,0 +1,52 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994, 1995 Waldorf Electronics
+ * Written by Ralf Baechle and Andreas Busse
+ * Copyright (C) 1995 - 1999 Ralf Baechle
+ * Copyright (C) 1996 Paul M. Antoine
+ * Modified for DECStation and hence R3000 support by Paul M. Antoine
+ * Further modifications by David S. Miller and Harald Koerfgen
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ */
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+
+	LEAF(start)
+	/* Save boot rom start args */
+	move	s0, a0
+	move	s1, a1
+	move	s2, a2
+	move	s3, a3
+
+	/* Clear BSS */
+	PTR_LA	a0, _edata
+	PTR_LA	a2, _end
+1:	PTR_S	zero, 0(a0)
+	PTR_ADDIU a0, a0, PTRSIZE
+	bne	a2, a0, 1b
+
+	PTR_LA	a0, (.heap)	     /* heap address */
+	PTR_LA	sp, (.stack + 8192)  /* stack address */
+
+	PTR_LA	t9, decompress_kernel
+	jalr	t9
+
+2:
+	move	a0, s0
+	move	a1, s1
+	move	a2, s2
+	move	a3, s3
+	PTR_LI	t9, KERNEL_ENTRY
+	jalr	t9
+
+3:
+	b	3b
+
+	END(start)
+
+	.comm .heap,BOOT_HEAP_SIZE,4
+	.comm .stack,4096*2,4
diff --git a/arch/mips/boot/compressed/ld.script b/arch/mips/boot/compressed/ld.script
new file mode 100644
index 000000000..0ebb66727
--- /dev/null
+++ b/arch/mips/boot/compressed/ld.script
@@ -0,0 +1,60 @@
+/*
+ * ld.script for compressed kernel support of MIPS
+ *
+ * Copyright (C) 2009 Lemote Inc.
+ * Author: Wu Zhangjin <wuzhanjing@gmail.com>
+ * Copyright (C) 2010 "Wu Zhangjin" <wuzhanjing@gmail.com>
+ */
+
+OUTPUT_ARCH(mips)
+ENTRY(start)
+PHDRS {
+	text PT_LOAD FLAGS(7); /* RWX */
+}
+SECTIONS
+{
+	/* Text and read-only data */
+	/* . = VMLINUZ_LOAD_ADDRESS; */
+	.text : {
+		*(.text)
+		*(.rodata)
+	}: text
+	/* End of text section */
+
+	/* Writable data */
+	.data : {
+		*(.data)
+		/* Put the compressed image here */
+		__image_begin = .;
+		*(.image)
+		__image_end = .;
+		CONSTRUCTORS
+		. = ALIGN(16);
+	}
+
+	.appended_dtb : {
+		__appended_dtb = .;
+		/* leave space for appended DTB */
+		. += 0x100000;
+	}
+
+	_edata = .;
+	/* End of data section */
+
+	/* BSS */
+	.bss : {
+		*(.bss)
+	}
+	. = ALIGN(16);
+	_end = .;
+
+	/* Sections to be discarded */
+	/DISCARD/ : {
+		*(.MIPS.options)
+		*(.options)
+		*(.pdr)
+		*(.reginfo)
+		*(.comment)
+		*(.note)
+	}
+}
diff --git a/arch/mips/boot/compressed/string.c b/arch/mips/boot/compressed/string.c
new file mode 100644
index 000000000..f0eb251e4
--- /dev/null
+++ b/arch/mips/boot/compressed/string.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/mips/boot/compressed/string.c
+ *
+ * Very small subset of simple string routines
+ */
+
+#include <linux/compiler_attributes.h>
+#include <linux/types.h>
+#include <asm/string.h>
+
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	int i;
+	const char *s = src;
+	char *d = dest;
+
+	for (i = 0; i < n; i++)
+		d[i] = s[i];
+	return dest;
+}
+
+void *memset(void *s, int c, size_t n)
+{
+	int i;
+	char *ss = s;
+
+	for (i = 0; i < n; i++)
+		ss[i] = c;
+	return s;
+}
+
+void * __weak memmove(void *dest, const void *src, size_t n)
+{
+	unsigned int i;
+	const char *s = src;
+	char *d = dest;
+
+	if ((uintptr_t)dest < (uintptr_t)src) {
+		for (i = 0; i < n; i++)
+			d[i] = s[i];
+	} else {
+		for (i = n; i > 0; i--)
+			d[i - 1] = s[i - 1];
+	}
+	return dest;
+}
diff --git a/arch/mips/boot/compressed/uart-16550.c b/arch/mips/boot/compressed/uart-16550.c
new file mode 100644
index 000000000..529e77a64
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-16550.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 16550 compatible uart based serial debug support for zboot
+ */
+
+#include <linux/types.h>
+#include <linux/serial_reg.h>
+
+#include <asm/addrspace.h>
+
+#include "decompress.h"
+
+#if defined(CONFIG_MACH_LOONGSON64) || defined(CONFIG_MIPS_MALTA)
+#define UART_BASE 0x1fd003f8
+#define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
+#endif
+
+#ifdef CONFIG_MACH_INGENIC
+#define INGENIC_UART_BASE_ADDR	(0x10030000 + 0x1000 * CONFIG_ZBOOT_INGENIC_UART)
+#define PORT(offset) (CKSEG1ADDR(INGENIC_UART_BASE_ADDR) + (4 * offset))
+#endif
+
+#ifdef CONFIG_ECONET
+#define EN75_UART_BASE	0x1fbf0003
+#define PORT(offset)	(CKSEG1ADDR(EN75_UART_BASE) + (4 * (offset)))
+#endif
+
+#ifndef IOTYPE
+#define IOTYPE char
+#endif
+
+#ifndef PORT
+#error please define the serial port address for your own machine
+#endif
+
+static inline unsigned int serial_in(int offset)
+{
+	return *((volatile IOTYPE *)PORT(offset)) & 0xFF;
+}
+
+static inline void serial_out(int offset, int value)
+{
+	*((volatile IOTYPE *)PORT(offset)) = value & 0xFF;
+}
+
+void putc(char c)
+{
+	int timeout = 1000000;
+
+	while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
+		;
+
+	serial_out(UART_TX, c);
+}
diff --git a/arch/mips/boot/compressed/uart-alchemy.c b/arch/mips/boot/compressed/uart-alchemy.c
new file mode 100644
index 000000000..003967c08
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-alchemy.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <asm/mach-au1x00/au1000.h>
+
+#include "decompress.h"
+
+void putc(char c)
+{
+	alchemy_uart_putchar(AU1000_UART0_PHYS_ADDR, c);
+}
diff --git a/arch/mips/boot/compressed/uart-ath79.c b/arch/mips/boot/compressed/uart-ath79.c
new file mode 100644
index 000000000..d68682092
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-ath79.c
@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "../../ath79/early_printk.c"
diff --git a/arch/mips/boot/compressed/uart-prom.c b/arch/mips/boot/compressed/uart-prom.c
new file mode 100644
index 000000000..5fa3b9945
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-prom.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <asm/setup.h>
+
+#include "decompress.h"
+
+void putc(char c)
+{
+	prom_putchar(c);
+}