Merge branch 'uprobes/core' of... (d0616c17) · Commits · 方亚芬 / raspberrypi_linux

arch/x86/include/asm/processor.h

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -759,6 +759,8 @@ static inline void update_debugctlmsr(unsigned long debugctlmsr)
	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);		wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
	}		}

			extern void set_task_blockstep(struct task_struct *task, bool on);

	/*		/*
	* from system description table in BIOS. Mostly for MCA use, but		* from system description table in BIOS. Mostly for MCA use, but
	* others may find it useful:		* others may find it useful:

arch/x86/include/asm/uprobes.h

+2 −1

Original line number	Original line	Diff line number	Diff line
	@@ -42,10 +42,11 @@ struct arch_uprobe {
	};		};

	struct arch_uprobe_task {		struct arch_uprobe_task {
	unsigned long saved_trap_nr;
	#ifdef CONFIG_X86_64		#ifdef CONFIG_X86_64
	unsigned long saved_scratch_register;		unsigned long saved_scratch_register;
	#endif		#endif
			unsigned int saved_trap_nr;
			unsigned int saved_tf;
	};		};

	extern int arch_uprobe_analyze_insn(struct arch_uprobe aup, struct mm_struct mm, unsigned long addr);		extern int arch_uprobe_analyze_insn(struct arch_uprobe aup, struct mm_struct mm, unsigned long addr);

arch/x86/kernel/step.c

+33 −20

Original line number	Original line	Diff line number	Diff line
	@@ -157,6 +157,33 @@ static int enable_single_step(struct task_struct *child)
	return 1;		return 1;
	}		}

			void set_task_blockstep(struct task_struct *task, bool on)
			{
			unsigned long debugctl;

			/*
			* Ensure irq/preemption can't change debugctl in between.
			* Note also that both TIF_BLOCKSTEP and debugctl should
			* be changed atomically wrt preemption.
			* FIXME: this means that set/clear TIF_BLOCKSTEP is simply
			* wrong if task != current, SIGKILL can wakeup the stopped
			* tracee and set/clear can play with the running task, this
			* can confuse the next __switch_to_xtra().
			*/
			local_irq_disable();
			debugctl = get_debugctlmsr();
			if (on) {
			debugctl \|= DEBUGCTLMSR_BTF;
			set_tsk_thread_flag(task, TIF_BLOCKSTEP);
			} else {
			debugctl &= ~DEBUGCTLMSR_BTF;
			clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
			}
			if (task == current)
			update_debugctlmsr(debugctl);
			local_irq_enable();
			}

	/*		/*
	* Enable single or block step.		* Enable single or block step.
	*/		*/
	@@ -169,19 +196,10 @@ static void enable_step(struct task_struct *child, bool block)
	* So no one should try to use debugger block stepping in a program		* So no one should try to use debugger block stepping in a program
	* that uses user-mode single stepping itself.		* that uses user-mode single stepping itself.
	*/		*/
	if (enable_single_step(child) && block) {		if (enable_single_step(child) && block)
	unsigned long debugctl = get_debugctlmsr();		set_task_blockstep(child, true);
			else if (test_tsk_thread_flag(child, TIF_BLOCKSTEP))
	debugctl \|= DEBUGCTLMSR_BTF;		set_task_blockstep(child, false);
	update_debugctlmsr(debugctl);
	set_tsk_thread_flag(child, TIF_BLOCKSTEP);
	} else if (test_tsk_thread_flag(child, TIF_BLOCKSTEP)) {
	unsigned long debugctl = get_debugctlmsr();

	debugctl &= ~DEBUGCTLMSR_BTF;
	update_debugctlmsr(debugctl);
	clear_tsk_thread_flag(child, TIF_BLOCKSTEP);
	}
	}		}

	void user_enable_single_step(struct task_struct *child)		void user_enable_single_step(struct task_struct *child)
	@@ -199,13 +217,8 @@ void user_disable_single_step(struct task_struct *child)
	/*		/*
	* Make sure block stepping (BTF) is disabled.		* Make sure block stepping (BTF) is disabled.
	*/		*/
	if (test_tsk_thread_flag(child, TIF_BLOCKSTEP)) {		if (test_tsk_thread_flag(child, TIF_BLOCKSTEP))
	unsigned long debugctl = get_debugctlmsr();		set_task_blockstep(child, false);

	debugctl &= ~DEBUGCTLMSR_BTF;
	update_debugctlmsr(debugctl);
	clear_tsk_thread_flag(child, TIF_BLOCKSTEP);
	}

	/* Always clear TIF_SINGLESTEP... */		/* Always clear TIF_SINGLESTEP... */
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);		clear_tsk_thread_flag(child, TIF_SINGLESTEP);

arch/x86/kernel/uprobes.c

+51 −1

Original line number	Original line	Diff line number	Diff line
	@@ -41,6 +41,9 @@
	/* Adjust the return address of a call insn */		/* Adjust the return address of a call insn */
	#define UPROBE_FIX_CALL 0x2		#define UPROBE_FIX_CALL 0x2

			/* Instruction will modify TF, don't change it */
			#define UPROBE_FIX_SETF 0x4

	#define UPROBE_FIX_RIP_AX 0x8000		#define UPROBE_FIX_RIP_AX 0x8000
	#define UPROBE_FIX_RIP_CX 0x4000		#define UPROBE_FIX_RIP_CX 0x4000

	@@ -239,6 +242,10 @@ static void prepare_fixups(struct arch_uprobe auprobe, struct insn insn)
	insn_get_opcode(insn); /* should be a nop */		insn_get_opcode(insn); /* should be a nop */

	switch (OPCODE1(insn)) {		switch (OPCODE1(insn)) {
			case 0x9d:
			/* popf */
			auprobe->fixups \|= UPROBE_FIX_SETF;
			break;
	case 0xc3: /* ret/lret */		case 0xc3: /* ret/lret */
	case 0xcb:		case 0xcb:
	case 0xc2:		case 0xc2:
	@@ -646,7 +653,7 @@ void arch_uprobe_abort_xol(struct arch_uprobe auprobe, struct pt_regs regs)
	* Skip these instructions as per the currently known x86 ISA.		* Skip these instructions as per the currently known x86 ISA.
	* 0x66* { 0x90 \| 0x0f 0x1f \| 0x0f 0x19 \| 0x87 0xc0 }		* 0x66* { 0x90 \| 0x0f 0x1f \| 0x0f 0x19 \| 0x87 0xc0 }
	*/		*/
	bool arch_uprobe_skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)		static bool __skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
	{		{
	int i;		int i;

	@@ -673,3 +680,46 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
	}		}
	return false;		return false;
	}		}

			bool arch_uprobe_skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
			{
			bool ret = __skip_sstep(auprobe, regs);
			if (ret && (regs->flags & X86_EFLAGS_TF))
			send_sig(SIGTRAP, current, 0);
			return ret;
			}

			void arch_uprobe_enable_step(struct arch_uprobe *auprobe)
			{
			struct task_struct *task = current;
			struct arch_uprobe_task *autask = &task->utask->autask;
			struct pt_regs *regs = task_pt_regs(task);

			autask->saved_tf = !!(regs->flags & X86_EFLAGS_TF);

			regs->flags \|= X86_EFLAGS_TF;
			if (test_tsk_thread_flag(task, TIF_BLOCKSTEP))
			set_task_blockstep(task, false);
			}

			void arch_uprobe_disable_step(struct arch_uprobe *auprobe)
			{
			struct task_struct *task = current;
			struct arch_uprobe_task *autask = &task->utask->autask;
			bool trapped = (task->utask->state == UTASK_SSTEP_TRAPPED);
			struct pt_regs *regs = task_pt_regs(task);
			/*
			* The state of TIF_BLOCKSTEP was not saved so we can get an extra
			* SIGTRAP if we do not clear TF. We need to examine the opcode to
			* make it right.
			*/
			if (unlikely(trapped)) {
			if (!autask->saved_tf)
			regs->flags &= ~X86_EFLAGS_TF;
			} else {
			if (autask->saved_tf)
			send_sig(SIGTRAP, task, 0);
			else if (!(auprobe->fixups & UPROBE_FIX_SETF))
			regs->flags &= ~X86_EFLAGS_TF;
			}
			}

include/linux/sched.h

+2 −1

Original line number	Original line	Diff line number	Diff line
	@@ -446,7 +446,8 @@ extern int get_dumpable(struct mm_struct *mm);
	#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */		#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */
	#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */		#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */

	#define MMF_HAS_UPROBES 19 /* might have uprobes */		#define MMF_HAS_UPROBES 19 /* has uprobes */
			#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */

	#define MMF_INIT_MASK (MMF_DUMPABLE_MASK \| MMF_DUMP_FILTER_MASK)		#define MMF_INIT_MASK (MMF_DUMPABLE_MASK \| MMF_DUMP_FILTER_MASK)