Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 174 insertions, 0 deletions

diff --git a/include/linux/objtool.h b/include/linux/objtool.h
new file mode 100644
index 000000000..33212e93f
--- /dev/null
+++ b/include/linux/objtool.h
@@ -0,0 +1,174 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_OBJTOOL_H
+#define _LINUX_OBJTOOL_H
+
+#include <linux/objtool_types.h>
+
+#ifdef CONFIG_OBJTOOL
+
+#include <asm/asm.h>
+
+#ifndef __ASSEMBLY__
+
+#define UNWIND_HINT(type, sp_reg, sp_offset, signal)	\
+	"987: \n\t"						\
+	".pushsection .discard.unwind_hints\n\t"		\
+	/* struct unwind_hint */				\
+	".long 987b - .\n\t"					\
+	".short " __stringify(sp_offset) "\n\t"			\
+	".byte " __stringify(sp_reg) "\n\t"			\
+	".byte " __stringify(type) "\n\t"			\
+	".byte " __stringify(signal) "\n\t"			\
+	".balign 4 \n\t"					\
+	".popsection\n\t"
+
+/*
+ * This macro marks the given function's stack frame as "non-standard", which
+ * tells objtool to ignore the function when doing stack metadata validation.
+ * It should only be used in special cases where you're 100% sure it won't
+ * affect the reliability of frame pointers and kernel stack traces.
+ *
+ * For more information, see tools/objtool/Documentation/objtool.txt.
+ */
+#define STACK_FRAME_NON_STANDARD(func) \
+	static void __used __section(".discard.func_stack_frame_non_standard") \
+		*__func_stack_frame_non_standard_##func = func
+
+/*
+ * STACK_FRAME_NON_STANDARD_FP() is a frame-pointer-specific function ignore
+ * for the case where a function is intentionally missing frame pointer setup,
+ * but otherwise needs objtool/ORC coverage when frame pointers are disabled.
+ */
+#ifdef CONFIG_FRAME_POINTER
+#define STACK_FRAME_NON_STANDARD_FP(func) STACK_FRAME_NON_STANDARD(func)
+#else
+#define STACK_FRAME_NON_STANDARD_FP(func)
+#endif
+
+#define ANNOTATE_NOENDBR					\
+	"986: \n\t"						\
+	".pushsection .discard.noendbr\n\t"			\
+	".long 986b\n\t"					\
+	".popsection\n\t"
+
+#define ASM_REACHABLE							\
+	"998:\n\t"							\
+	".pushsection .discard.reachable\n\t"				\
+	".long 998b\n\t"						\
+	".popsection\n\t"
+
+#else /* __ASSEMBLY__ */
+
+/*
+ * This macro indicates that the following intra-function call is valid.
+ * Any non-annotated intra-function call will cause objtool to issue a warning.
+ */
+#define ANNOTATE_INTRA_FUNCTION_CALL				\
+	999:							\
+	.pushsection .discard.intra_function_calls;		\
+	.long 999b;						\
+	.popsection;
+
+/*
+ * In asm, there are two kinds of code: normal C-type callable functions and
+ * the rest.  The normal callable functions can be called by other code, and
+ * don't do anything unusual with the stack.  Such normal callable functions
+ * are annotated with the ENTRY/ENDPROC macros.  Most asm code falls in this
+ * category.  In this case, no special debugging annotations are needed because
+ * objtool can automatically generate the ORC data for the ORC unwinder to read
+ * at runtime.
+ *
+ * Anything which doesn't fall into the above category, such as syscall and
+ * interrupt handlers, tends to not be called directly by other functions, and
+ * often does unusual non-C-function-type things with the stack pointer.  Such
+ * code needs to be annotated such that objtool can understand it.  The
+ * following CFI hint macros are for this type of code.
+ *
+ * These macros provide hints to objtool about the state of the stack at each
+ * instruction.  Objtool starts from the hints and follows the code flow,
+ * making automatic CFI adjustments when it sees pushes and pops, filling out
+ * the debuginfo as necessary.  It will also warn if it sees any
+ * inconsistencies.
+ */
+.macro UNWIND_HINT type:req sp_reg=0 sp_offset=0 signal=0
+.Lhere_\@:
+	.pushsection .discard.unwind_hints
+		/* struct unwind_hint */
+		.long .Lhere_\@ - .
+		.short \sp_offset
+		.byte \sp_reg
+		.byte \type
+		.byte \signal
+		.balign 4
+	.popsection
+.endm
+
+.macro STACK_FRAME_NON_STANDARD func:req
+	.pushsection .discard.func_stack_frame_non_standard, "aw"
+	.long \func - .
+	.popsection
+.endm
+
+.macro STACK_FRAME_NON_STANDARD_FP func:req
+#ifdef CONFIG_FRAME_POINTER
+	STACK_FRAME_NON_STANDARD \func
+#endif
+.endm
+
+.macro ANNOTATE_NOENDBR
+.Lhere_\@:
+	.pushsection .discard.noendbr
+	.long	.Lhere_\@
+	.popsection
+.endm
+
+/*
+ * Use objtool to validate the entry requirement that all code paths do
+ * VALIDATE_UNRET_END before RET.
+ *
+ * NOTE: The macro must be used at the beginning of a global symbol, otherwise
+ * it will be ignored.
+ */
+.macro VALIDATE_UNRET_BEGIN
+#if defined(CONFIG_NOINSTR_VALIDATION) && \
+	(defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_SRSO))
+.Lhere_\@:
+	.pushsection .discard.validate_unret
+	.long	.Lhere_\@ - .
+	.popsection
+#endif
+.endm
+
+.macro REACHABLE
+.Lhere_\@:
+	.pushsection .discard.reachable
+	.long	.Lhere_\@
+	.popsection
+.endm
+
+#endif /* __ASSEMBLY__ */
+
+#else /* !CONFIG_OBJTOOL */
+
+#ifndef __ASSEMBLY__
+
+#define UNWIND_HINT(type, sp_reg, sp_offset, signal) "\n\t"
+#define STACK_FRAME_NON_STANDARD(func)
+#define STACK_FRAME_NON_STANDARD_FP(func)
+#define ANNOTATE_NOENDBR
+#define ASM_REACHABLE
+#else
+#define ANNOTATE_INTRA_FUNCTION_CALL
+.macro UNWIND_HINT type:req sp_reg=0 sp_offset=0 signal=0
+.endm
+.macro STACK_FRAME_NON_STANDARD func:req
+.endm
+.macro ANNOTATE_NOENDBR
+.endm
+.macro REACHABLE
+.endm
+#endif
+
+#endif /* CONFIG_OBJTOOL */
+
+#endif /* _LINUX_OBJTOOL_H */