Commit 2e21d853 authored by Will Deacon's avatar Will Deacon
Browse files

Merge branch 'for-next/stacktrace' into for-next/kasan 

Merge in stack unwinding work to cater for 8-byte aligned stack frames
which may be generated following optimisations to CONFIG_KASAN_OUTLINE.

* for-next/stacktrace:
  arm64: stacktrace: Relax frame record alignment requirement to 8 bytes
  arm64: Change the on_*stack functions to take a size argument
  arm64: Implement stack trace termination record
parents c4681547 33c222ae

arch/arm64/include/asm/processor.h

+6 −6
Original line number Diff line number Diff line
@@ -332,10 +332,10 @@ long get_tagged_addr_ctrl(struct task_struct *task); 
#define current_top_of_stack()								\

({											\

	struct stack_info _info;							\

	BUG_ON(!on_accessible_stack(current, current_stack_pointer, &_info));	\

	BUG_ON(!on_accessible_stack(current, current_stack_pointer, 1, &_info));	\

	_info.high;									\

})

#define on_thread_stack()	(on_task_stack(current, current_stack_pointer, NULL))

#define on_thread_stack()	(on_task_stack(current, current_stack_pointer, 1, NULL))



#endif /* __ASSEMBLY__ */

#endif /* __ASM_PROCESSOR_H */

arch/arm64/include/asm/sdei.h

+4 −3
Original line number Diff line number Diff line
@@ -42,8 +42,9 @@ unsigned long sdei_arch_get_entry_point(int conduit); 


struct stack_info;



bool _on_sdei_stack(unsigned long sp, struct stack_info *info);

static inline bool on_sdei_stack(unsigned long sp,

bool _on_sdei_stack(unsigned long sp, unsigned long size,

		    struct stack_info *info);

static inline bool on_sdei_stack(unsigned long sp, unsigned long size,

				struct stack_info *info)

{

	if (!IS_ENABLED(CONFIG_VMAP_STACK))
@@ -51,7 +52,7 @@ static inline bool on_sdei_stack(unsigned long sp, 
	if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE))

		return false;

	if (in_nmi())

		return _on_sdei_stack(sp, info);

		return _on_sdei_stack(sp, size, info);



	return false;

}

arch/arm64/include/asm/stacktrace.h

+16 −16
Original line number Diff line number Diff line
@@ -69,14 +69,14 @@ extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, 


DECLARE_PER_CPU(unsigned long *, irq_stack_ptr);



static inline bool on_stack(unsigned long sp, unsigned long low,

				unsigned long high, enum stack_type type,

				struct stack_info *info)

static inline bool on_stack(unsigned long sp, unsigned long size,

			    unsigned long low, unsigned long high,

			    enum stack_type type, struct stack_info *info)

{

	if (!low)

		return false;



	if (sp < low || sp >= high)

	if (sp < low || sp + size < sp || sp + size > high)

		return false;



	if (info) {
@@ -87,38 +87,38 @@ static inline bool on_stack(unsigned long sp, unsigned long low, 
	return true;

}



static inline bool on_irq_stack(unsigned long sp,

static inline bool on_irq_stack(unsigned long sp, unsigned long size,

				struct stack_info *info)

{

	unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr);

	unsigned long high = low + IRQ_STACK_SIZE;



	return on_stack(sp, low, high, STACK_TYPE_IRQ, info);

	return on_stack(sp, size, low, high, STACK_TYPE_IRQ, info);

}



static inline bool on_task_stack(const struct task_struct *tsk,

				 unsigned long sp,

				 unsigned long sp, unsigned long size,

				 struct stack_info *info)

{

	unsigned long low = (unsigned long)task_stack_page(tsk);

	unsigned long high = low + THREAD_SIZE;



	return on_stack(sp, low, high, STACK_TYPE_TASK, info);

	return on_stack(sp, size, low, high, STACK_TYPE_TASK, info);

}



#ifdef CONFIG_VMAP_STACK

DECLARE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack);



static inline bool on_overflow_stack(unsigned long sp,

static inline bool on_overflow_stack(unsigned long sp, unsigned long size,

				struct stack_info *info)

{

	unsigned long low = (unsigned long)raw_cpu_ptr(overflow_stack);

	unsigned long high = low + OVERFLOW_STACK_SIZE;



	return on_stack(sp, low, high, STACK_TYPE_OVERFLOW, info);

	return on_stack(sp, size, low, high, STACK_TYPE_OVERFLOW, info);

}

#else

static inline bool on_overflow_stack(unsigned long sp,

static inline bool on_overflow_stack(unsigned long sp, unsigned long size,

			struct stack_info *info) { return false; }

#endif
@@ -128,21 +128,21 @@ static inline bool on_overflow_stack(unsigned long sp, 
 * context.

 */

static inline bool on_accessible_stack(const struct task_struct *tsk,

				       unsigned long sp,

				       unsigned long sp, unsigned long size,

				       struct stack_info *info)

{

	if (info)

		info->type = STACK_TYPE_UNKNOWN;



	if (on_task_stack(tsk, sp, info))

	if (on_task_stack(tsk, sp, size, info))

		return true;

	if (tsk != current || preemptible())

		return false;

	if (on_irq_stack(sp, info))

	if (on_irq_stack(sp, size, info))

		return true;

	if (on_overflow_stack(sp, info))

	if (on_overflow_stack(sp, size, info))

		return true;

	if (on_sdei_stack(sp, info))

	if (on_sdei_stack(sp, size, info))

		return true;



	return false;

arch/arm64/kernel/entry.S

+1 −1
Original line number Diff line number Diff line
@@ -285,7 +285,7 @@ alternative_else_nop_endif 
	stp	lr, x21, [sp, #S_LR]



	/*

	 * For exceptions from EL0, create a terminal frame record.

	 * For exceptions from EL0, create a final frame record.

	 * For exceptions from EL1, create a synthetic frame record so the

	 * interrupted code shows up in the backtrace.

	 */

arch/arm64/kernel/head.S

+19 −6
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <asm/asm_pointer_auth.h>

#include <asm/assembler.h>

#include <asm/boot.h>

#include <asm/bug.h>

#include <asm/ptrace.h>

#include <asm/asm-offsets.h>

#include <asm/cache.h>
@@ -393,6 +394,18 @@ SYM_FUNC_START_LOCAL(__create_page_tables) 
	ret	x28

SYM_FUNC_END(__create_page_tables)



	/*

	 * Create a final frame record at task_pt_regs(current)->stackframe, so

	 * that the unwinder can identify the final frame record of any task by

	 * its location in the task stack. We reserve the entire pt_regs space

	 * for consistency with user tasks and kthreads.

	 */

	.macro setup_final_frame

	sub	sp, sp, #PT_REGS_SIZE

	stp	xzr, xzr, [sp, #S_STACKFRAME]

	add	x29, sp, #S_STACKFRAME

	.endm



/*

 * The following fragment of code is executed with the MMU enabled.

 *
@@ -447,9 +460,9 @@ SYM_FUNC_START_LOCAL(__primary_switched) 
#endif

	bl	switch_to_vhe			// Prefer VHE if possible

	add	sp, sp, #16

	mov	x29, #0

	mov	x30, #0

	b	start_kernel

	setup_final_frame

	bl	start_kernel

	ASM_BUG()

SYM_FUNC_END(__primary_switched)



	.pushsection ".rodata", "a"
@@ -639,14 +652,14 @@ SYM_FUNC_START_LOCAL(__secondary_switched) 
	cbz	x2, __secondary_too_slow

	msr	sp_el0, x2

	scs_load x2, x3

	mov	x29, #0

	mov	x30, #0

	setup_final_frame



#ifdef CONFIG_ARM64_PTR_AUTH

	ptrauth_keys_init_cpu x2, x3, x4, x5

#endif



	b	secondary_start_kernel

	bl	secondary_start_kernel

	ASM_BUG()

SYM_FUNC_END(__secondary_switched)



SYM_FUNC_START_LOCAL(__secondary_too_slow)