Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 184 insertions, 0 deletions

diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
new file mode 100644
index 000000000..cc96b04cc
--- /dev/null
+++ b/arch/s390/boot/startup.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/string.h>
+#include <linux/elf.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/kexec.h>
+#include <asm/sclp.h>
+#include <asm/diag.h>
+#include <asm/uv.h>
+#include "compressed/decompressor.h"
+#include "boot.h"
+
+extern char __boot_data_start[], __boot_data_end[];
+extern char __boot_data_preserved_start[], __boot_data_preserved_end[];
+unsigned long __bootdata_preserved(__kaslr_offset);
+
+/*
+ * Some code and data needs to stay below 2 GB, even when the kernel would be
+ * relocated above 2 GB, because it has to use 31 bit addresses.
+ * Such code and data is part of the .dma section, and its location is passed
+ * over to the decompressed / relocated kernel via the .boot.preserved.data
+ * section.
+ */
+extern char _sdma[], _edma[];
+extern char _stext_dma[], _etext_dma[];
+extern struct exception_table_entry _start_dma_ex_table[];
+extern struct exception_table_entry _stop_dma_ex_table[];
+unsigned long __bootdata_preserved(__sdma) = __pa(&_sdma);
+unsigned long __bootdata_preserved(__edma) = __pa(&_edma);
+unsigned long __bootdata_preserved(__stext_dma) = __pa(&_stext_dma);
+unsigned long __bootdata_preserved(__etext_dma) = __pa(&_etext_dma);
+struct exception_table_entry *
+	__bootdata_preserved(__start_dma_ex_table) = _start_dma_ex_table;
+struct exception_table_entry *
+	__bootdata_preserved(__stop_dma_ex_table) = _stop_dma_ex_table;
+
+int _diag210_dma(struct diag210 *addr);
+int _diag26c_dma(void *req, void *resp, enum diag26c_sc subcode);
+int _diag14_dma(unsigned long rx, unsigned long ry1, unsigned long subcode);
+void _diag0c_dma(struct hypfs_diag0c_entry *entry);
+void _diag308_reset_dma(void);
+struct diag_ops __bootdata_preserved(diag_dma_ops) = {
+	.diag210 = _diag210_dma,
+	.diag26c = _diag26c_dma,
+	.diag14 = _diag14_dma,
+	.diag0c = _diag0c_dma,
+	.diag308_reset = _diag308_reset_dma
+};
+static struct diag210 _diag210_tmp_dma __section(".dma.data");
+struct diag210 *__bootdata_preserved(__diag210_tmp_dma) = &_diag210_tmp_dma;
+
+void error(char *x)
+{
+	sclp_early_printk("\n\n");
+	sclp_early_printk(x);
+	sclp_early_printk("\n\n -- System halted");
+
+	disabled_wait();
+}
+
+#ifdef CONFIG_KERNEL_UNCOMPRESSED
+unsigned long mem_safe_offset(void)
+{
+	return vmlinux.default_lma + vmlinux.image_size + vmlinux.bss_size;
+}
+#endif
+
+static void rescue_initrd(unsigned long addr)
+{
+	if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD))
+		return;
+	if (!INITRD_START || !INITRD_SIZE)
+		return;
+	if (addr <= INITRD_START)
+		return;
+	memmove((void *)addr, (void *)INITRD_START, INITRD_SIZE);
+	INITRD_START = addr;
+}
+
+static void copy_bootdata(void)
+{
+	if (__boot_data_end - __boot_data_start != vmlinux.bootdata_size)
+		error(".boot.data section size mismatch");
+	memcpy((void *)vmlinux.bootdata_off, __boot_data_start, vmlinux.bootdata_size);
+	if (__boot_data_preserved_end - __boot_data_preserved_start != vmlinux.bootdata_preserved_size)
+		error(".boot.preserved.data section size mismatch");
+	memcpy((void *)vmlinux.bootdata_preserved_off, __boot_data_preserved_start, vmlinux.bootdata_preserved_size);
+}
+
+static void handle_relocs(unsigned long offset)
+{
+	Elf64_Rela *rela_start, *rela_end, *rela;
+	int r_type, r_sym, rc;
+	Elf64_Addr loc, val;
+	Elf64_Sym *dynsym;
+
+	rela_start = (Elf64_Rela *) vmlinux.rela_dyn_start;
+	rela_end = (Elf64_Rela *) vmlinux.rela_dyn_end;
+	dynsym = (Elf64_Sym *) vmlinux.dynsym_start;
+	for (rela = rela_start; rela < rela_end; rela++) {
+		loc = rela->r_offset + offset;
+		val = rela->r_addend;
+		r_sym = ELF64_R_SYM(rela->r_info);
+		if (r_sym) {
+			if (dynsym[r_sym].st_shndx != SHN_UNDEF)
+				val += dynsym[r_sym].st_value + offset;
+		} else {
+			/*
+			 * 0 == undefined symbol table index (STN_UNDEF),
+			 * used for R_390_RELATIVE, only add KASLR offset
+			 */
+			val += offset;
+		}
+		r_type = ELF64_R_TYPE(rela->r_info);
+		rc = arch_kexec_do_relocs(r_type, (void *) loc, val, 0);
+		if (rc)
+			error("Unknown relocation type");
+	}
+}
+
+/*
+ * This function clears the BSS section of the decompressed Linux kernel and NOT the decompressor's.
+ */
+static void clear_bss_section(void)
+{
+	memset((void *)vmlinux.default_lma + vmlinux.image_size, 0, vmlinux.bss_size);
+}
+
+void startup_kernel(void)
+{
+	unsigned long random_lma;
+	unsigned long safe_addr;
+	void *img;
+
+	store_ipl_parmblock();
+	safe_addr = mem_safe_offset();
+	safe_addr = read_ipl_report(safe_addr);
+	uv_query_info();
+	rescue_initrd(safe_addr);
+	sclp_early_read_info();
+	setup_boot_command_line();
+	parse_boot_command_line();
+	setup_memory_end();
+	detect_memory();
+
+	random_lma = __kaslr_offset = 0;
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_enabled) {
+		random_lma = get_random_base(safe_addr);
+		if (random_lma) {
+			__kaslr_offset = random_lma - vmlinux.default_lma;
+			img = (void *)vmlinux.default_lma;
+			vmlinux.default_lma += __kaslr_offset;
+			vmlinux.entry += __kaslr_offset;
+			vmlinux.bootdata_off += __kaslr_offset;
+			vmlinux.bootdata_preserved_off += __kaslr_offset;
+			vmlinux.rela_dyn_start += __kaslr_offset;
+			vmlinux.rela_dyn_end += __kaslr_offset;
+			vmlinux.dynsym_start += __kaslr_offset;
+		}
+	}
+
+	if (!IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED)) {
+		img = decompress_kernel();
+		memmove((void *)vmlinux.default_lma, img, vmlinux.image_size);
+	} else if (__kaslr_offset)
+		memcpy((void *)vmlinux.default_lma, img, vmlinux.image_size);
+
+	clear_bss_section();
+	copy_bootdata();
+	if (IS_ENABLED(CONFIG_RELOCATABLE))
+		handle_relocs(__kaslr_offset);
+
+	if (__kaslr_offset) {
+		/*
+		 * Save KASLR offset for early dumps, before vmcore_info is set.
+		 * Mark as uneven to distinguish from real vmcore_info pointer.
+		 */
+		S390_lowcore.vmcore_info = __kaslr_offset | 0x1UL;
+		/* Clear non-relocated kernel */
+		if (IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED))
+			memset(img, 0, vmlinux.image_size);
+	}
+	vmlinux.entry();
+}