From a257cacc38718c83cee003487e03197f237f5c3f Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 15 Feb 2022 13:41:02 +0100 Subject: asm-generic: Define CONFIG_HAVE_FUNCTION_DESCRIPTORS Replace HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR by a config option named CONFIG_HAVE_FUNCTION_DESCRIPTORS and use it instead of 'dereference_function_descriptor' macro to know whether an arch has function descriptors. To limit churn in one of the following patches, use an #ifdef/#else construct with empty first part instead of an #ifndef in asm-generic/sections.h On powerpc, make sure the config option matches the ABI used by the compiler with a BUILD_BUG_ON() and add missing _CALL_ELF=2 when calling 'sparse' so that sparse sees the same piece of code as GCC. And include a helper to check whether an arch has function descriptors or not : have_function_descriptors() Signed-off-by: Christophe Leroy Reviewed-by: Kees Cook Reviewed-by: Nicholas Piggin Acked-by: Helge Deller Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/4a0f11fb0ea74a3197bc44dd7ba25e53a24fd03d.1644928018.git.christophe.leroy@csgroup.eu --- arch/Kconfig | 3 +++ arch/ia64/Kconfig | 1 + arch/ia64/include/asm/sections.h | 2 -- arch/parisc/Kconfig | 1 + arch/parisc/include/asm/sections.h | 2 -- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/sections.h | 2 -- arch/powerpc/kernel/ptrace/ptrace.c | 6 ++++++ include/asm-generic/sections.h | 8 +++++++- include/linux/kallsyms.h | 2 +- 10 files changed, 20 insertions(+), 8 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 678a80713b21..fe24174cb63c 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -205,6 +205,9 @@ config HAVE_FUNCTION_ERROR_INJECTION config HAVE_NMI bool +config HAVE_FUNCTION_DESCRIPTORS + bool + config TRACE_IRQFLAGS_SUPPORT bool diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index a7e01573abd8..da85c3b23b16 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -35,6 +35,7 @@ config IA64 select HAVE_SETUP_PER_CPU_AREA select TTY select HAVE_ARCH_TRACEHOOK + select HAVE_FUNCTION_DESCRIPTORS select HAVE_VIRT_CPU_ACCOUNTING select HUGETLB_PAGE_SIZE_VARIABLE if HUGETLB_PAGE select VIRT_TO_BUS diff --git a/arch/ia64/include/asm/sections.h b/arch/ia64/include/asm/sections.h index 35f24e52149a..2460d365a057 100644 --- a/arch/ia64/include/asm/sections.h +++ b/arch/ia64/include/asm/sections.h @@ -27,8 +27,6 @@ extern char __start_gate_brl_fsys_bubble_down_patchlist[], __end_gate_brl_fsys_b extern char __start_unwind[], __end_unwind[]; extern char __start_ivt_text[], __end_ivt_text[]; -#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1 - #undef dereference_function_descriptor static inline void *dereference_function_descriptor(void *ptr) { diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 43c1c880def6..82e7ab1a9764 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -69,6 +69,7 @@ config PARISC select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_SOFTIRQ_ON_OWN_STACK if IRQSTACKS select TRACE_IRQFLAGS_SUPPORT + select HAVE_FUNCTION_DESCRIPTORS if 64BIT help The PA-RISC microprocessor is designed by Hewlett-Packard and used diff --git a/arch/parisc/include/asm/sections.h b/arch/parisc/include/asm/sections.h index bb52aea0cb21..c8092e4d94de 100644 --- a/arch/parisc/include/asm/sections.h +++ b/arch/parisc/include/asm/sections.h @@ -9,8 +9,6 @@ extern char __alt_instructions[], __alt_instructions_end[]; #ifdef CONFIG_64BIT -#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1 - #undef dereference_function_descriptor void *dereference_function_descriptor(void *); diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index b779603978e1..a0c9cd0bbc85 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -202,6 +202,7 @@ config PPC select HAVE_EFFICIENT_UNALIGNED_ACCESS if !(CPU_LITTLE_ENDIAN && POWER7_CPU) select HAVE_FAST_GUP select HAVE_FTRACE_MCOUNT_RECORD + select HAVE_FUNCTION_DESCRIPTORS if PPC64 && !CPU_LITTLE_ENDIAN select HAVE_FUNCTION_ERROR_INJECTION select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h index baca39f4c6d3..7728a7a146c3 100644 --- a/arch/powerpc/include/asm/sections.h +++ b/arch/powerpc/include/asm/sections.h @@ -56,8 +56,6 @@ static inline int overlaps_kernel_text(unsigned long start, unsigned long end) #ifdef PPC64_ELF_ABI_v1 -#define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1 - #undef dereference_function_descriptor static inline void *dereference_function_descriptor(void *ptr) { diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c index c43f77e2ac31..1212a812a7ab 100644 --- a/arch/powerpc/kernel/ptrace/ptrace.c +++ b/arch/powerpc/kernel/ptrace/ptrace.c @@ -445,4 +445,10 @@ void __init pt_regs_check(void) * real registers. */ BUILD_BUG_ON(PT_DSCR < sizeof(struct user_pt_regs) / sizeof(unsigned long)); + +#ifdef PPC64_ELF_ABI_v1 + BUILD_BUG_ON(!IS_ENABLED(CONFIG_HAVE_FUNCTION_DESCRIPTORS)); +#else + BUILD_BUG_ON(IS_ENABLED(CONFIG_HAVE_FUNCTION_DESCRIPTORS)); +#endif } diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h index 690f741764e1..3ef83e1aebee 100644 --- a/include/asm-generic/sections.h +++ b/include/asm-generic/sections.h @@ -59,11 +59,17 @@ extern char __noinstr_text_start[], __noinstr_text_end[]; extern __visible const void __nosave_begin, __nosave_end; /* Function descriptor handling (if any). Override in asm/sections.h */ -#ifndef dereference_function_descriptor +#ifdef CONFIG_HAVE_FUNCTION_DESCRIPTORS +#else #define dereference_function_descriptor(p) ((void *)(p)) #define dereference_kernel_function_descriptor(p) ((void *)(p)) #endif +static inline bool have_function_descriptors(void) +{ + return IS_ENABLED(CONFIG_HAVE_FUNCTION_DESCRIPTORS); +} + /** * memory_contains - checks if an object is contained within a memory region * @begin: virtual address of the beginning of the memory region diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h index 4176c7eca7b5..ce1bd2fbf23e 100644 --- a/include/linux/kallsyms.h +++ b/include/linux/kallsyms.h @@ -48,7 +48,7 @@ static inline int is_ksym_addr(unsigned long addr) static inline void *dereference_symbol_descriptor(void *ptr) { -#ifdef HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR +#ifdef CONFIG_HAVE_FUNCTION_DESCRIPTORS struct module *mod; ptr = dereference_kernel_function_descriptor(ptr); -- cgit v1.2.3-59-g8ed1b