csky: Fixup perf probe -x hungup (c2e59d1f) · Commits · 戴 / test

case: # perf probe -x /lib/libc-2.28.9000.so memcpy # perf record -e probe_libc:memcpy -aR sleep 1 System hangup and cpu get in trap_c loop, because our hardware singlestep state could still get interrupt signal. When we get in uprobe_xol singlestep slot, we should disable irq in pt_regs->psr. And is_swbp_insn() need a csky arch implementation with a low 16bit mask. Signed-off-by:

Guo Ren <guoren@linux.alibaba.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>

arch/csky/kernel/probes/uprobes.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -11,6 +11,11 @@

		#define UPROBE_TRAP_NR UINT_MAX

		bool is_swbp_insn(uprobe_opcode_t *insn)
		{
		return (*insn & 0xffff) == UPROBE_SWBP_INSN;
		}

		unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
		{
		return instruction_pointer(regs);

arch/csky/kernel/ptrace.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -41,6 +41,9 @@ static void singlestep_disable(struct task_struct *tsk)

		regs = task_pt_regs(tsk);
		regs->sr = (regs->sr & TRACE_MODE_MASK) \| TRACE_MODE_RUN;

		/* Enable irq */
		regs->sr \|= BIT(6);
		}

		static void singlestep_enable(struct task_struct *tsk)
		@@ -49,6 +52,9 @@ static void singlestep_enable(struct task_struct *tsk)

		regs = task_pt_regs(tsk);
		regs->sr = (regs->sr & TRACE_MODE_MASK) \| TRACE_MODE_SI;

		/* Disable irq */
		regs->sr &= ~BIT(6);
		}

		/*

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