powerpc: Add show_user_instructions() (88b0fe17) · Commits · 戴 / test

show_user_instructions() is a slightly modified version of show_instructions() that allows userspace instruction dump. This will be useful within show_signal_msg() to dump userspace instructions of the faulty location. Here is a sample of what show_user_instructions() outputs: pandafault[10850]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe pandafault[10850]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040 The current->comm and current->pid printed can serve as a glue that links the instructions dump to its originator, allowing messages to be interleaved in the logs. Signed-off-by:

Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by:

Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/stacktrace.h

0 → 100644

+13 −0

Original line number	Diff line number	Diff line
		/* SPDX-License-Identifier: GPL-2.0 */
		/*
		* Stack trace functions.
		*
		* Copyright 2018, Murilo Opsfelder Araujo, IBM Corporation.
		*/

		#ifndef _ASM_POWERPC_STACKTRACE_H
		#define _ASM_POWERPC_STACKTRACE_H

		void show_user_instructions(struct pt_regs *regs);

		#endif /* _ASM_POWERPC_STACKTRACE_H */

arch/powerpc/kernel/process.c

+32 −0

Original line number	Diff line number	Diff line
		@@ -1299,6 +1299,38 @@ static void show_instructions(struct pt_regs *regs)
		pr_cont("\n");
		}

		void show_user_instructions(struct pt_regs *regs)
		{
		unsigned long pc;
		int i;

		pc = regs->nip - (instructions_to_print * 3 / 4 * sizeof(int));

		pr_info("%s[%d]: code: ", current->comm, current->pid);

		for (i = 0; i < instructions_to_print; i++) {
		int instr;

		if (!(i % 8) && (i > 0)) {
		pr_cont("\n");
		pr_info("%s[%d]: code: ", current->comm, current->pid);
		}

		if (probe_kernel_address((unsigned int __user *)pc, instr)) {
		pr_cont("XXXXXXXX ");
		} else {
		if (regs->nip == pc)
		pr_cont("<%08x> ", instr);
		else
		pr_cont("%08x ", instr);
		}

		pc += sizeof(int);
		}

		pr_cont("\n");
		}

		struct regbit {
		unsigned long bit;
		const char *name;

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