Commit 6f612579 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'objtool-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull objtool updates from Ingo Molar:
 "Build footprint & performance improvements:

   - Reduce memory usage with CONFIG_DEBUG_INFO=y

     In the worst case of an allyesconfig+CONFIG_DEBUG_INFO=y kernel,
     DWARF creates almost 200 million relocations, ballooning objtool's
     peak heap usage to 53GB. These patches reduce that to 25GB.

     On a distro-type kernel with kernel IBT enabled, they reduce
     objtool's peak heap usage from 4.2GB to 2.8GB.

     These changes also improve the runtime significantly.

  Debuggability improvements:

   - Add the unwind_debug command-line option, for more extend unwinding
     debugging output
   - Limit unreachable warnings to once per function
   - Add verbose option for disassembling affected functions
   - Include backtrace in verbose mode
   - Detect missing __noreturn annotations
   - Ignore exc_double_fault() __noreturn warnings
   - Remove superfluous global_noreturns entries
   - Move noreturn function list to separate file
   - Add __kunit_abort() to noreturns

  Unwinder improvements:

   - Allow stack operations in UNWIND_HINT_UNDEFINED regions
   - drm/vmwgfx: Add unwind hints around RBP clobber

  Cleanups:

   - Move the x86 entry thunk restore code into thunk functions
   - x86/unwind/orc: Use swap() instead of open coding it
   - Remove unnecessary/unused variables

  Fixes for modern stack canary handling"

* tag 'objtool-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
  x86/orc: Make the is_callthunk() definition depend on CONFIG_BPF_JIT=y
  objtool: Skip reading DWARF section data
  objtool: Free insns when done
  objtool: Get rid of reloc->rel[a]
  objtool: Shrink elf hash nodes
  objtool: Shrink reloc->sym_reloc_entry
  objtool: Get rid of reloc->jump_table_start
  objtool: Get rid of reloc->addend
  objtool: Get rid of reloc->type
  objtool: Get rid of reloc->offset
  objtool: Get rid of reloc->idx
  objtool: Get rid of reloc->list
  objtool: Allocate relocs in advance for new rela sections
  objtool: Add for_each_reloc()
  objtool: Don't free memory in elf_close()
  objtool: Keep GElf_Rel[a] structs synced
  objtool: Add elf_create_section_pair()
  objtool: Add mark_sec_changed()
  objtool: Fix reloc_hash size
  objtool: Consolidate rel/rela handling
  ...
parents 4d675181 301cf77e

Documentation/admin-guide/kernel-parameters.txt

+6 −0
Original line number Diff line number Diff line
@@ -6598,6 +6598,12 @@ 
	unknown_nmi_panic

			[X86] Cause panic on unknown NMI.



	unwind_debug	[X86-64]

			Enable unwinder debug output.  This can be

			useful for debugging certain unwinder error

			conditions, including corrupt stacks and

			bad/missing unwinder metadata.



	usbcore.authorized_default=

			[USB] Default USB device authorization:

			(default -1 = authorized except for wireless USB,

arch/powerpc/kernel/smp.c

+1 −0
Original line number Diff line number Diff line
@@ -1605,6 +1605,7 @@ static void add_cpu_to_masks(int cpu) 
}



/* Activate a secondary processor. */

__no_stack_protector

void start_secondary(void *unused)

{

	unsigned int cpu = raw_smp_processor_id();

arch/x86/entry/thunk_64.S

+8 −12
Original line number Diff line number Diff line
@@ -26,17 +26,7 @@ SYM_FUNC_START(\name) 
	pushq %r11



	call \func

	jmp  __thunk_restore

SYM_FUNC_END(\name)

	_ASM_NOKPROBE(\name)

	.endm



	THUNK preempt_schedule_thunk, preempt_schedule

	THUNK preempt_schedule_notrace_thunk, preempt_schedule_notrace

	EXPORT_SYMBOL(preempt_schedule_thunk)

	EXPORT_SYMBOL(preempt_schedule_notrace_thunk)



SYM_CODE_START_LOCAL(__thunk_restore)

	popq %r11

	popq %r10

	popq %r9
@@ -48,5 +38,11 @@ SYM_CODE_START_LOCAL(__thunk_restore) 
	popq %rdi

	popq %rbp

	RET

	_ASM_NOKPROBE(__thunk_restore)

SYM_CODE_END(__thunk_restore)
 
SYM_FUNC_END(\name)

	_ASM_NOKPROBE(\name)

	.endm



THUNK preempt_schedule_thunk, preempt_schedule

THUNK preempt_schedule_notrace_thunk, preempt_schedule_notrace

EXPORT_SYMBOL(preempt_schedule_thunk)

EXPORT_SYMBOL(preempt_schedule_notrace_thunk)

arch/x86/include/asm/alternative.h

+0 −5
Original line number Diff line number Diff line
@@ -113,7 +113,6 @@ extern void callthunks_patch_builtin_calls(void); 
extern void callthunks_patch_module_calls(struct callthunk_sites *sites,

					  struct module *mod);

extern void *callthunks_translate_call_dest(void *dest);

extern bool is_callthunk(void *addr);

extern int x86_call_depth_emit_accounting(u8 **pprog, void *func);

#else

static __always_inline void callthunks_patch_builtin_calls(void) {}
@@ -124,10 +123,6 @@ static __always_inline void *callthunks_translate_call_dest(void *dest) 
{

	return dest;

}

static __always_inline bool is_callthunk(void *addr)

{

	return false;

}

static __always_inline int x86_call_depth_emit_accounting(u8 **pprog,

							  void *func)

{

arch/x86/include/asm/unwind_hints.h

+9 −0
Original line number Diff line number Diff line
@@ -76,9 +76,18 @@ 


#else



#define UNWIND_HINT_UNDEFINED \

	UNWIND_HINT(UNWIND_HINT_TYPE_UNDEFINED, 0, 0, 0)



#define UNWIND_HINT_FUNC \

	UNWIND_HINT(UNWIND_HINT_TYPE_FUNC, ORC_REG_SP, 8, 0)



#define UNWIND_HINT_SAVE \

	UNWIND_HINT(UNWIND_HINT_TYPE_SAVE, 0, 0, 0)



#define UNWIND_HINT_RESTORE \

	UNWIND_HINT(UNWIND_HINT_TYPE_RESTORE, 0, 0, 0)



#endif /* __ASSEMBLY__ */



#endif /* _ASM_X86_UNWIND_HINTS_H */