Commit 44688ffd authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'objtool-urgent-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull objtool fixes from Thomas Gleixner:

 - Handle __ubsan_handle_builtin_unreachable() correctly and treat it as
   noreturn

 - Allow architectures to select uaccess validation

 - Use the non-instrumented bit test for test_cpu_has() to prevent
   escape from non-instrumentable regions

 - Use arch_ prefixed atomics for JUMP_LABEL=n builds to prevent escape
   from non-instrumentable regions

 - Mark a few tiny inline as __always_inline to prevent GCC from
   bringing them out of line and instrumenting them

 - Mark the empty stub context_tracking_enabled() as always inline as
   GCC brings them out of line and instruments the empty shell

 - Annotate ex_handler_msr_mce() as dead end

* tag 'objtool-urgent-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/extable: Annotate ex_handler_msr_mce() as a dead end
  context_tracking: Always inline empty stubs
  x86: Always inline on_thread_stack() and current_top_of_stack()
  jump_label,noinstr: Avoid instrumentation for JUMP_LABEL=n builds
  x86/cpu: Elide KCSAN for cpu_has() and friends
  objtool: Mark __ubsan_handle_builtin_unreachable() as noreturn
  objtool: Add CONFIG_HAVE_UACCESS_VALIDATION
parents b2c9a83d 2028a255

arch/Kconfig

+4 −0
Original line number Diff line number Diff line
@@ -1048,6 +1048,10 @@ config HAVE_NOINSTR_HACK 
config HAVE_NOINSTR_VALIDATION

	bool



config HAVE_UACCESS_VALIDATION

	bool

	select OBJTOOL



config HAVE_STACK_VALIDATION

	bool

	help

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -258,6 +258,7 @@ config X86 
	select HAVE_PREEMPT_DYNAMIC_CALL

	select HAVE_RSEQ

	select HAVE_SYSCALL_TRACEPOINTS

	select HAVE_UACCESS_VALIDATION		if HAVE_OBJTOOL

	select HAVE_UNSTABLE_SCHED_CLOCK

	select HAVE_USER_RETURN_NOTIFIER

	select HAVE_GENERIC_VDSO

arch/x86/include/asm/cpufeature.h

+1 −1
Original line number Diff line number Diff line
@@ -54,7 +54,7 @@ extern const char * const x86_power_flags[32]; 
extern const char * const x86_bug_flags[NBUGINTS*32];



#define test_cpu_cap(c, bit)						\

	 test_bit(bit, (unsigned long *)((c)->x86_capability))

	 arch_test_bit(bit, (unsigned long *)((c)->x86_capability))



/*

 * There are 32 bits/features in each mask word.  The high bits

arch/x86/include/asm/extable.h

+6 −2
Original line number Diff line number Diff line
@@ -42,9 +42,13 @@ extern int ex_get_fixup_type(unsigned long ip); 
extern void early_fixup_exception(struct pt_regs *regs, int trapnr);



#ifdef CONFIG_X86_MCE

extern void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr);

extern void __noreturn ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr);

#else

static inline void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr) { }

static inline void __noreturn ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr)

{

	for (;;)

		cpu_relax();

}

#endif



#if defined(CONFIG_BPF_JIT) && defined(CONFIG_X86_64)

arch/x86/include/asm/processor.h

+2 −2
Original line number Diff line number Diff line
@@ -559,7 +559,7 @@ static __always_inline void native_swapgs(void) 
#endif

}



static inline unsigned long current_top_of_stack(void)

static __always_inline unsigned long current_top_of_stack(void)

{

	/*

	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
@@ -569,7 +569,7 @@ static inline unsigned long current_top_of_stack(void) 
	return this_cpu_read_stable(cpu_current_top_of_stack);

}



static inline bool on_thread_stack(void)

static __always_inline bool on_thread_stack(void)

{

	return (unsigned long)(current_top_of_stack() -

			       current_stack_pointer) < THREAD_SIZE;