4 files changed, 97 insertions, 5 deletions
diff --git a/arch/s390/boot/compressed/.gitignore b/arch/s390/boot/compressed/.gitignore
index 765a08f1bd77..01d93832cf4a 100644
--- a/arch/s390/boot/compressed/.gitignore
+++ b/arch/s390/boot/compressed/.gitignore
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 vmlinux
 vmlinux.lds
+vmlinux.syms
diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile
index b235ed95a3d8..e0502222706a 100644
--- a/arch/s390/boot/compressed/Makefile
+++ b/arch/s390/boot/compressed/Makefile
@@ -10,21 +10,39 @@ GCOV_PROFILE := n
 UBSAN_SANITIZE := n
 KASAN_SANITIZE := n
 
-obj-y	:= $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) piggy.o info.o
+obj-y	:= $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) info.o
+obj-all := $(obj-y) piggy.o syms.o
 targets	:= vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
 targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
-targets += info.bin $(obj-y)
+targets += info.bin syms.bin vmlinux.syms $(obj-all)
 
 KBUILD_AFLAGS := $(KBUILD_AFLAGS_DECOMPRESSOR)
 KBUILD_CFLAGS := $(KBUILD_CFLAGS_DECOMPRESSOR)
 OBJCOPYFLAGS :=
 
 OBJECTS := $(addprefix $(obj)/,$(obj-y))
+OBJECTS_ALL := $(addprefix $(obj)/,$(obj-all))
 
 LDFLAGS_vmlinux := --oformat $(LD_BFD) -e startup -T
-$(obj)/vmlinux: $(obj)/vmlinux.lds $(objtree)/arch/s390/boot/startup.a $(OBJECTS) FORCE
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(objtree)/arch/s390/boot/startup.a $(OBJECTS_ALL) FORCE
 	$(call if_changed,ld)
 
+LDFLAGS_vmlinux.syms := --oformat $(LD_BFD) -e startup -T
+$(obj)/vmlinux.syms: $(obj)/vmlinux.lds $(objtree)/arch/s390/boot/startup.a $(OBJECTS) FORCE
+	$(call if_changed,ld)
+
+quiet_cmd_dumpsyms = DUMPSYMS $<
+define cmd_dumpsyms
+	$(NM) -n -S --format=bsd "$<" | $(PERL) -ne '/(\w+)\s+(\w+)\s+[tT]\s+(\w+)/ and printf "%x %x %s\0",hex $$1,hex $$2,$$3' > "$@"
+endef
+
+$(obj)/syms.bin: $(obj)/vmlinux.syms FORCE
+	$(call if_changed,dumpsyms)
+
+OBJCOPYFLAGS_syms.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section .data=.decompressor.syms
+$(obj)/syms.o: $(obj)/syms.bin FORCE
+	$(call if_changed,objcopy)
+
 OBJCOPYFLAGS_info.bin := -O binary --only-section=.vmlinux.info --set-section-flags .vmlinux.info=load
 $(obj)/info.bin: vmlinux FORCE
 	$(call if_changed,objcopy)
diff --git a/arch/s390/boot/compressed/vmlinux.lds.S b/arch/s390/boot/compressed/vmlinux.lds.S
index 9427e2cd0c15..152ac6f875c0 100644
--- a/arch/s390/boot/compressed/vmlinux.lds.S
+++ b/arch/s390/boot/compressed/vmlinux.lds.S
@@ -82,6 +82,14 @@ SECTIONS
 		*(.vmlinux.info)
 	}
 
+	.decompressor.syms : {
+		. += 1; /* make sure we have \0 before the first entry */
+		. = ALIGN(2);
+		_decompressor_syms_start = .;
+		*(.decompressor.syms)
+		_decompressor_syms_end = .;
+	}
+
 #ifdef CONFIG_KERNEL_UNCOMPRESSED
 	. = 0x100000;
 #else
diff --git a/arch/s390/boot/pgm_check_info.c b/arch/s390/boot/pgm_check_info.c
index 829548c22444..8ba8136adb4d 100644
--- a/arch/s390/boot/pgm_check_info.c
+++ b/arch/s390/boot/pgm_check_info.c
@@ -19,6 +19,65 @@ static char *as_hex(char *dst, unsigned long val, int pad)
 	return end;
 }
 
+static char *symstart(char *p)
+{
+	while (*p)
+		p--;
+	return p + 1;
+}
+
+extern char _decompressor_syms_start[], _decompressor_syms_end[];
+static noinline char *findsym(unsigned long ip, unsigned short *off, unsigned short *len)
+{
+	/* symbol entries are in a form "10000 c4 startup\0" */
+	char *a = _decompressor_syms_start;
+	char *b = _decompressor_syms_end;
+	unsigned long start;
+	unsigned long size;
+	char *pivot;
+	char *endp;
+
+	while (a < b) {
+		pivot = symstart(a + (b - a) / 2);
+		start = simple_strtoull(pivot, &endp, 16);
+		size = simple_strtoull(endp + 1, &endp, 16);
+		if (ip < start) {
+			b = pivot;
+			continue;
+		}
+		if (ip > start + size) {
+			a = pivot + strlen(pivot) + 1;
+			continue;
+		}
+		*off = ip - start;
+		*len = size;
+		return endp + 1;
+	}
+	return NULL;
+}
+
+static noinline char *strsym(void *ip)
+{
+	static char buf[64];
+	unsigned short off;
+	unsigned short len;
+	char *p;
+
+	p = findsym((unsigned long)ip, &off, &len);
+	if (p) {
+		strncpy(buf, p, sizeof(buf));
+		/* reserve 15 bytes for offset/len in symbol+0x1234/0x1234 */
+		p = buf + strnlen(buf, sizeof(buf) - 15);
+		strcpy(p, "+0x");
+		p = as_hex(p + 3, off, 0);
+		strcpy(p, "/0x");
+		as_hex(p + 3, len, 0);
+	} else {
+		as_hex(buf, (unsigned long)ip, 16);
+	}
+	return buf;
+}
+
 void decompressor_printk(const char *fmt, ...)
 {
 	char buf[1024] = { 0 };
@@ -38,6 +97,11 @@ void decompressor_printk(const char *fmt, ...)
 		case 's':
 			p = buf + strlcat(buf, va_arg(args, char *), sizeof(buf));
 			break;
+		case 'p':
+			if (*++fmt != 'S')
+				goto out;
+			p = buf + strlcat(buf, strsym(va_arg(args, void *)), sizeof(buf));
+			break;
 		case 'l':
 			if (*++fmt != 'x' || end - p <= max(sizeof(long) * 2, pad))
 				goto out;
@@ -67,9 +131,10 @@ void print_pgm_check_info(void)
 			    S390_lowcore.pgm_code, S390_lowcore.pgm_ilc >> 1);
 	if (kaslr_enabled)
 		decompressor_printk("Kernel random base: %lx\n", __kaslr_offset);
-	decompressor_printk("PSW : %016lx %016lx\n",
+	decompressor_printk("PSW : %016lx %016lx (%pS)\n",
 			    S390_lowcore.psw_save_area.mask,
-			    S390_lowcore.psw_save_area.addr);
+			    S390_lowcore.psw_save_area.addr,
+			    (void *)S390_lowcore.psw_save_area.addr);
 	decompressor_printk(
 		"      R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x P:%x AS:%x CC:%x PM:%x RI:%x EA:%x\n",
 		psw->per, psw->dat, psw->io, psw->ext, psw->key, psw->mcheck,