objtool/idle: Validate __cpuidle code as noinstr

Idle code is very like entry code in that RCU isn't available. As
such, add a little validation.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195540.373461409@infradead.org
This commit is contained in:
Peter Zijlstra 2023-01-12 20:43:31 +01:00 committed by Ingo Molnar
parent 00717eb8c9
commit 2b5a0e425e
32 changed files with 27 additions and 45 deletions

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@ -27,7 +27,6 @@ SECTIONS
HEAD_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
*(.fixup)
*(.gnu.warning)

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@ -85,7 +85,6 @@ SECTIONS
_stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -96,7 +96,6 @@
SOFTIRQENTRY_TEXT \
TEXT_TEXT \
SCHED_TEXT \
CPUIDLE_TEXT \
LOCK_TEXT \
KPROBES_TEXT \
ARM_STUBS_TEXT \

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@ -175,7 +175,6 @@ SECTIONS
ENTRY_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
HYPERVISOR_TEXT

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@ -34,7 +34,6 @@ SECTIONS
SOFTIRQENTRY_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
*(.fixup)

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@ -41,7 +41,6 @@ SECTIONS
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
*(.fixup)

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@ -51,7 +51,6 @@ SECTIONS {
__end_ivt_text = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -43,7 +43,6 @@ SECTIONS
.text : {
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -48,7 +48,6 @@ SECTIONS {
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
*(.fixup)
. = ALIGN(16);

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@ -19,7 +19,6 @@ SECTIONS
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
*(.fixup)
*(.gnu.warning)

View File

@ -19,7 +19,6 @@ SECTIONS
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
*(.fixup)
*(.gnu.warning)

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@ -36,7 +36,6 @@ SECTIONS {
EXIT_TEXT
EXIT_CALL
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -61,7 +61,6 @@ SECTIONS
.text : {
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -24,7 +24,6 @@ SECTIONS
.text : {
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT

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@ -52,7 +52,6 @@ SECTIONS
_stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -86,7 +86,6 @@ SECTIONS
TEXT_TEXT
LOCK_TEXT
SCHED_TEXT
CPUIDLE_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT

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@ -111,7 +111,6 @@ SECTIONS
#endif
NOINSTR_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -39,7 +39,6 @@ SECTIONS
_stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
ENTRY_TEXT

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@ -42,7 +42,6 @@ SECTIONS
_stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
ENTRY_TEXT

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@ -42,7 +42,6 @@ SECTIONS
HEAD_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -29,7 +29,6 @@ SECTIONS
HEAD_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -50,7 +50,6 @@ SECTIONS
HEAD_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT

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@ -74,7 +74,6 @@ SECTIONS
_stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT

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@ -35,7 +35,6 @@ SECTIONS
_stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT

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@ -8,9 +8,6 @@
#include <asm/nospec-branch.h>
/* Provide __cpuidle; we can't safely include <linux/cpu.h> */
#define __cpuidle __section(".cpuidle.text")
/*
* Interrupt control:
*/
@ -45,13 +42,13 @@ static __always_inline void native_irq_enable(void)
asm volatile("sti": : :"memory");
}
static inline __cpuidle void native_safe_halt(void)
static __always_inline void native_safe_halt(void)
{
mds_idle_clear_cpu_buffers();
asm volatile("sti; hlt": : :"memory");
}
static inline __cpuidle void native_halt(void)
static __always_inline void native_halt(void)
{
mds_idle_clear_cpu_buffers();
asm volatile("hlt": : :"memory");
@ -84,7 +81,7 @@ static __always_inline void arch_local_irq_enable(void)
* Used in the idle loop; sti takes one instruction cycle
* to complete:
*/
static inline __cpuidle void arch_safe_halt(void)
static __always_inline void arch_safe_halt(void)
{
native_safe_halt();
}
@ -93,7 +90,7 @@ static inline __cpuidle void arch_safe_halt(void)
* Used when interrupts are already enabled or to
* shutdown the processor:
*/
static inline __cpuidle void halt(void)
static __always_inline void halt(void)
{
native_halt();
}

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@ -105,7 +105,7 @@ static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
* New with Core Duo processors, MWAIT can take some hints based on CPU
* capability.
*/
static inline void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
static __always_inline void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
{
if (static_cpu_has_bug(X86_BUG_MONITOR) || !current_set_polling_and_test()) {
if (static_cpu_has_bug(X86_BUG_CLFLUSH_MONITOR)) {

View File

@ -129,7 +129,6 @@ SECTIONS
HEAD_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
KPROBES_TEXT
SOFTIRQENTRY_TEXT

View File

@ -125,7 +125,6 @@ SECTIONS
ENTRY_TEXT
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
LOCK_TEXT
*(.fixup)
}

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@ -558,6 +558,9 @@
ALIGN_FUNCTION(); \
__noinstr_text_start = .; \
*(.noinstr.text) \
__cpuidle_text_start = .; \
*(.cpuidle.text) \
__cpuidle_text_end = .; \
__noinstr_text_end = .;
/*
@ -598,12 +601,6 @@
*(.spinlock.text) \
__lock_text_end = .;
#define CPUIDLE_TEXT \
ALIGN_FUNCTION(); \
__cpuidle_text_start = .; \
*(.cpuidle.text) \
__cpuidle_text_end = .;
#define KPROBES_TEXT \
ALIGN_FUNCTION(); \
__kprobes_text_start = .; \

View File

@ -232,11 +232,15 @@ struct ftrace_likely_data {
#endif
/* Section for code which can't be instrumented at all */
#define noinstr \
noinline notrace __attribute((__section__(".noinstr.text"))) \
#define __noinstr_section(section) \
noinline notrace __attribute((__section__(section))) \
__no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \
__no_sanitize_memory
#define noinstr __noinstr_section(".noinstr.text")
#define __cpuidle __noinstr_section(".cpuidle.text")
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */

View File

@ -176,9 +176,6 @@ void __noreturn cpu_startup_entry(enum cpuhp_state state);
void cpu_idle_poll_ctrl(bool enable);
/* Attach to any functions which should be considered cpuidle. */
#define __cpuidle __section(".cpuidle.text")
bool cpu_in_idle(unsigned long pc);
void arch_cpu_idle(void);

View File

@ -376,6 +376,7 @@ static int decode_instructions(struct objtool_file *file)
if (!strcmp(sec->name, ".noinstr.text") ||
!strcmp(sec->name, ".entry.text") ||
!strcmp(sec->name, ".cpuidle.text") ||
!strncmp(sec->name, ".text.__x86.", 12))
sec->noinstr = true;
@ -3365,6 +3366,12 @@ static inline bool noinstr_call_dest(struct objtool_file *file,
if (func->sec->noinstr)
return true;
/*
* If the symbol is a static_call trampoline, we can't tell.
*/
if (func->static_call_tramp)
return true;
/*
* The __ubsan_handle_*() calls are like WARN(), they only happen when
* something 'BAD' happened. At the risk of taking the machine down,
@ -4162,6 +4169,12 @@ static int validate_noinstr_sections(struct objtool_file *file)
warnings += validate_unwind_hints(file, sec);
}
sec = find_section_by_name(file->elf, ".cpuidle.text");
if (sec) {
warnings += validate_section(file, sec);
warnings += validate_unwind_hints(file, sec);
}
return warnings;
}