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authorSven Schnelle <svens@linux.ibm.com>2026-09-09 11:29:53 +0200
committerMasami Hiramatsu (Google) <mhiramat@kernel.org>2026-09-10 08:43:35 +0900
commitd22c3e0088e85be8131f7a9283f759cdbb20726d (patch)
tree9668df2aa27b26f850d3ba5ba1287e443803675c /arch/x86/boot/main.c
downloadlinux-stable-d22c3e0088e85be8131f7a9283f759cdbb20726d.tar.gz
linux-stable-d22c3e0088e85be8131f7a9283f759cdbb20726d.zip
selftests/ftrace: Fix unique symbol check in kprobe_non_uniq_symbol.tcgrafted
The current regex also matches symbols in modules, which makes the test fail on s390 where name_show is present only once in the kernel, but also multiple times in modules: 000001b1401cdc20 t name_show 000001b0c05e6c40 t name_show [mdev] 000001b0c0495f30 t name_show [i2c_core] Fix this by changing the regular expression to only match the function name. Link: https://lore.kernel.org/all/20260909092954.2200558-1-svens@linux.ibm.com/ Fixes: 03b80ff8023a ("selftests/ftrace: Add new test case which checks non unique symbol") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Diffstat (limited to 'arch/x86/boot/main.c')
-rw-r--r--arch/x86/boot/main.c179
1 files changed, 179 insertions, 0 deletions
diff --git a/arch/x86/boot/main.c b/arch/x86/boot/main.c
new file mode 100644
index 000000000..4e382d95e
--- /dev/null
+++ b/arch/x86/boot/main.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright 2007 rPath, Inc. - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * Main module for the real-mode kernel code
+ */
+#include <linux/build_bug.h>
+
+#include "boot.h"
+#include "string.h"
+
+struct boot_params boot_params __attribute__((aligned(16)));
+
+struct port_io_ops pio_ops;
+
+char *HEAP = _end;
+char *heap_end = _end; /* Default end of heap = no heap */
+
+/*
+ * Copy the header into the boot parameter block. Since this
+ * screws up the old-style command line protocol, adjust by
+ * filling in the new-style command line pointer instead.
+ */
+static void copy_boot_params(void)
+{
+ struct old_cmdline {
+ u16 cl_magic;
+ u16 cl_offset;
+ };
+ const struct old_cmdline * const oldcmd = absolute_pointer(OLD_CL_ADDRESS);
+
+ BUILD_BUG_ON(sizeof(boot_params) != 4096);
+ memcpy(&boot_params.hdr, &hdr, sizeof(hdr));
+
+ if (!boot_params.hdr.cmd_line_ptr && oldcmd->cl_magic == OLD_CL_MAGIC) {
+ /* Old-style command line protocol */
+ u16 cmdline_seg;
+
+ /*
+ * Figure out if the command line falls in the region
+ * of memory that an old kernel would have copied up
+ * to 0x90000...
+ */
+ if (oldcmd->cl_offset < boot_params.hdr.setup_move_size)
+ cmdline_seg = ds();
+ else
+ cmdline_seg = 0x9000;
+
+ boot_params.hdr.cmd_line_ptr = (cmdline_seg << 4) + oldcmd->cl_offset;
+ }
+}
+
+/*
+ * Query the keyboard lock status as given by the BIOS, and
+ * set the keyboard repeat rate to maximum. Unclear why the latter
+ * is done here; this might be possible to kill off as stale code.
+ */
+static void keyboard_init(void)
+{
+ struct biosregs ireg, oreg;
+
+ initregs(&ireg);
+
+ ireg.ah = 0x02; /* Get keyboard status */
+ intcall(0x16, &ireg, &oreg);
+ boot_params.kbd_status = oreg.al;
+
+ ireg.ax = 0x0305; /* Set keyboard repeat rate */
+ intcall(0x16, &ireg, NULL);
+}
+
+/*
+ * Get Intel SpeedStep (IST) information.
+ */
+static void query_ist(void)
+{
+ struct biosregs ireg, oreg;
+
+ /*
+ * Some older BIOSes apparently crash on this call, so filter
+ * it from machines too old to have SpeedStep at all.
+ */
+ if (cpu.level < 6)
+ return;
+
+ initregs(&ireg);
+ ireg.ax = 0xe980; /* IST Support */
+ ireg.edx = 0x47534943; /* Request value */
+ intcall(0x15, &ireg, &oreg);
+
+ boot_params.ist_info.signature = oreg.eax;
+ boot_params.ist_info.command = oreg.ebx;
+ boot_params.ist_info.event = oreg.ecx;
+ boot_params.ist_info.perf_level = oreg.edx;
+}
+
+/*
+ * Tell the BIOS what CPU mode we intend to run in.
+ */
+static void set_bios_mode(void)
+{
+#ifdef CONFIG_X86_64
+ struct biosregs ireg;
+
+ initregs(&ireg);
+ ireg.ax = 0xec00;
+ ireg.bx = 2;
+ intcall(0x15, &ireg, NULL);
+#endif
+}
+
+static void init_heap(void)
+{
+ char *stack_end;
+
+ if (boot_params.hdr.loadflags & CAN_USE_HEAP) {
+ stack_end = (char *) (current_stack_pointer - STACK_SIZE);
+ heap_end = (char *) ((size_t)boot_params.hdr.heap_end_ptr + 0x200);
+ if (heap_end > stack_end)
+ heap_end = stack_end;
+ } else {
+ /* Boot protocol 2.00 only, no heap available */
+ puts("WARNING: Ancient bootloader, some functionality may be limited!\n");
+ }
+}
+
+void main(void)
+{
+ init_default_io_ops();
+
+ /* First, copy the boot header into the "zeropage" */
+ copy_boot_params();
+
+ /* Initialize the early-boot console */
+ console_init();
+ if (cmdline_find_option_bool("debug"))
+ puts("early console in setup code\n");
+
+ /* End of heap check */
+ init_heap();
+
+ /* Make sure we have all the proper CPU support */
+ if (validate_cpu()) {
+ puts("Unable to boot - please use a kernel appropriate for your CPU.\n");
+ die();
+ }
+
+ /* Tell the BIOS what CPU mode we intend to run in */
+ set_bios_mode();
+
+ /* Detect memory layout */
+ detect_memory();
+
+ /* Set keyboard repeat rate (why?) and query the lock flags */
+ keyboard_init();
+
+ /* Query Intel SpeedStep (IST) information */
+ query_ist();
+
+ /* Query APM information */
+ if (IS_ENABLED(CONFIG_APM))
+ query_apm_bios();
+
+ /* Query EDD information */
+ if (IS_ENABLED(CONFIG_EDD))
+ query_edd();
+
+ /* Set the video mode */
+ set_video();
+
+ /* Do the last things and invoke protected mode */
+ go_to_protected_mode();
+}