Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3200ca80 authored by Andy Lutomirski's avatar Andy Lutomirski Committed by Ingo Molnar
Browse files

selftests/x86: Add test_vdso to test getcpu() 



I'll eventually add tests for more vDSO functions here.

Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Megha <megha.dey@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/945cd29901a62a3cc6ea7d6ee5e389ab1ec1ac0c.1479320367.git.luto@kernel.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent a582c540

tools/testing/selftests/x86/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ include ../lib.mk 


TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt ptrace_syscall test_mremap_vdso \

			check_initial_reg_state sigreturn ldt_gdt iopl \

			protection_keys

			protection_keys test_vdso

TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault test_syscall_vdso unwind_vdso \

			test_FCMOV test_FCOMI test_FISTTP \

			vdso_restorer

tools/testing/selftests/x86/test_vdso.c

0 → 100644
+123 −0
Original line number Diff line number Diff line 
/*

 * ldt_gdt.c - Test cases for LDT and GDT access

 * Copyright (c) 2011-2015 Andrew Lutomirski

 */



#define _GNU_SOURCE



#include <stdio.h>

#include <sys/time.h>

#include <time.h>

#include <stdlib.h>

#include <unistd.h>

#include <sys/syscall.h>

#include <dlfcn.h>

#include <string.h>

#include <errno.h>

#include <sched.h>

#include <stdbool.h>



#ifndef SYS_getcpu

# ifdef __x86_64__

#  define SYS_getcpu 309

# else

#  define SYS_getcpu 318

# endif

#endif



int nerrs = 0;



#ifdef __x86_64__

# define VSYS(x) (x)

#else

# define VSYS(x) 0

#endif



typedef long (*getcpu_t)(unsigned *, unsigned *, void *);



const getcpu_t vgetcpu = (getcpu_t)VSYS(0xffffffffff600800);

getcpu_t vdso_getcpu;



void fill_function_pointers()

{

	void *vdso = dlopen("linux-vdso.so.1",

			    RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);

	if (!vdso)

		vdso = dlopen("linux-gate.so.1",

			      RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);

	if (!vdso) {

		printf("[WARN]\tfailed to find vDSO\n");

		return;

	}



	vdso_getcpu = (getcpu_t)dlsym(vdso, "__vdso_getcpu");

	if (!vdso_getcpu)

		printf("Warning: failed to find getcpu in vDSO\n");

}



static long sys_getcpu(unsigned * cpu, unsigned * node,

		       void* cache)

{

	return syscall(__NR_getcpu, cpu, node, cache);

}



static void test_getcpu(void)

{

	printf("[RUN]\tTesting getcpu...\n");



	for (int cpu = 0; ; cpu++) {

		cpu_set_t cpuset;

		CPU_ZERO(&cpuset);

		CPU_SET(cpu, &cpuset);

		if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0)

			return;



		unsigned cpu_sys, cpu_vdso, cpu_vsys,

			node_sys, node_vdso, node_vsys;

		long ret_sys, ret_vdso = 1, ret_vsys = 1;

		unsigned node;



		ret_sys = sys_getcpu(&cpu_sys, &node_sys, 0);

		if (vdso_getcpu)

			ret_vdso = vdso_getcpu(&cpu_vdso, &node_vdso, 0);

		if (vgetcpu)

			ret_vsys = vgetcpu(&cpu_vsys, &node_vsys, 0);



		if (!ret_sys)

			node = node_sys;

		else if (!ret_vdso)

			node = node_vdso;

		else if (!ret_vsys)

			node = node_vsys;



		bool ok = true;

		if (!ret_sys && (cpu_sys != cpu || node_sys != node))

			ok = false;

		if (!ret_vdso && (cpu_vdso != cpu || node_vdso != node))

			ok = false;

		if (!ret_vsys && (cpu_vsys != cpu || node_vsys != node))

			ok = false;



		printf("[%s]\tCPU %u:", ok ? "OK" : "FAIL", cpu);

		if (!ret_sys)

			printf(" syscall: cpu %u, node %u", cpu_sys, node_sys);

		if (!ret_vdso)

			printf(" vdso: cpu %u, node %u", cpu_vdso, node_vdso);

		if (!ret_vsys)

			printf(" vsyscall: cpu %u, node %u", cpu_vsys,

			       node_vsys);

		printf("\n");



		if (!ok)

			nerrs++;

	}

}



int main(int argc, char **argv)

{

	fill_function_pointers();



	test_getcpu();



	return nerrs ? 1 : 0;

}