Messages in this thread Patch in this message | | | From | Nadav Amit <> | Subject | [RFC PATCH 3/5] x86: interface for accessing indirect branch locations | Date | Wed, 17 Oct 2018 17:54:18 -0700 |
| |
Adding a C interface to access the locations of indirect branches. To be used for dynamic patching.
Signed-off-by: Nadav Amit <namit@vmware.com> --- arch/x86/include/asm/nospec-branch.h | 1 - arch/x86/include/asm/sections.h | 2 ++ include/linux/module.h | 5 +++++ kernel/module.c | 8 ++++++++ 4 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index bd2d3a41e88c..a4496c141143 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -406,7 +406,6 @@ struct relpoline_entry { u8 reg; } __packed; - /* The Intel SPEC CTRL MSR base value cache */ extern u64 x86_spec_ctrl_base; diff --git a/arch/x86/include/asm/sections.h b/arch/x86/include/asm/sections.h index 8ea1cfdbeabc..e8dd9c40ecd5 100644 --- a/arch/x86/include/asm/sections.h +++ b/arch/x86/include/asm/sections.h @@ -4,6 +4,7 @@ #include <asm-generic/sections.h> #include <asm/extable.h> +#include <asm/nospec-branch.h> extern char __brk_base[], __brk_limit[]; extern struct exception_table_entry __stop___ex_table[]; @@ -11,6 +12,7 @@ extern char __end_rodata_aligned[]; #if defined(CONFIG_X86_64) extern char __end_rodata_hpage_align[]; +extern const struct relpoline_entry __relpolines[], __relpolines_end[]; #endif #endif /* _ASM_X86_SECTIONS_H */ diff --git a/include/linux/module.h b/include/linux/module.h index f807f15bebbe..29ff390f8339 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -39,6 +39,7 @@ struct modversion_info { struct module; struct exception_table_entry; +struct relpoline_entry; struct module_kobject { struct kobject kobj; @@ -387,6 +388,10 @@ struct module { unsigned int num_exentries; struct exception_table_entry *extable; + /* Cachepolines */ + unsigned int num_relpolines; + struct relpoline_entry *relpolines; + /* Startup function. */ int (*init)(void); diff --git a/kernel/module.c b/kernel/module.c index 49a405891587..e34fc28875bd 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -64,6 +64,7 @@ #include <linux/bsearch.h> #include <linux/dynamic_debug.h> #include <linux/audit.h> +#include <asm/nospec-branch.h> #include <uapi/linux/module.h> #include "module-internal.h" @@ -256,6 +257,7 @@ static void mod_update_bounds(struct module *mod) #ifdef CONFIG_KGDB_KDB struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ #endif /* CONFIG_KGDB_KDB */ +struct list_head *cachepoline_modules = &modules; static void module_assert_mutex(void) { @@ -3125,6 +3127,12 @@ static int find_module_sections(struct module *mod, struct load_info *info) mod->extable = section_objs(info, "__ex_table", sizeof(*mod->extable), &mod->num_exentries); +#ifdef CONFIG_X86_64 + mod->relpolines = section_objs(info, "__relpolines", + sizeof(*mod->relpolines), + &mod->num_relpolines); +#endif + if (section_addr(info, "__obsparm")) pr_warn("%s: Ignoring obsolete parameters\n", mod->name); -- 2.17.1
| |