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426d1aff31
This reverts commit ed68d7e9b9.
The patch wasn't quite correct -- there are non-Intel (and hence
non-486) CPUs that we support that don't have CPUID. Since we no
longer require CPUID for sync_core(), just revert the patch.
I think the relevant CPUs are Geode and Elan, but I'm not sure.
In principle, we should try to do better at identifying CPUID-less
CPUs in early boot, but that's more complicated.
Reported-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Matthew Whitehead <tedheadster@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: xen-devel <Xen-devel@lists.xen.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/82acde18a108b8e353180dd6febcc2876df33f24.1481307769.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
101 lines
2.1 KiB
C
101 lines
2.1 KiB
C
/* -*- linux-c -*- ------------------------------------------------------- *
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright 2007-2008 rPath, Inc. - All Rights Reserved
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*
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* This file is part of the Linux kernel, and is made available under
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* the terms of the GNU General Public License version 2.
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*
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* ----------------------------------------------------------------------- */
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/*
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* arch/x86/boot/cpu.c
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*
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* Check for obligatory CPU features and abort if the features are not
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* present.
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*/
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#include "boot.h"
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#ifdef CONFIG_X86_FEATURE_NAMES
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#include "cpustr.h"
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#endif
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static char *cpu_name(int level)
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{
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static char buf[6];
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if (level == 64) {
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return "x86-64";
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} else {
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if (level == 15)
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level = 6;
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sprintf(buf, "i%d86", level);
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return buf;
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}
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}
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static void show_cap_strs(u32 *err_flags)
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{
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int i, j;
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#ifdef CONFIG_X86_FEATURE_NAMES
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const unsigned char *msg_strs = (const unsigned char *)x86_cap_strs;
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for (i = 0; i < NCAPINTS; i++) {
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u32 e = err_flags[i];
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for (j = 0; j < 32; j++) {
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if (msg_strs[0] < i ||
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(msg_strs[0] == i && msg_strs[1] < j)) {
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/* Skip to the next string */
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msg_strs += 2;
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while (*msg_strs++)
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;
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}
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if (e & 1) {
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if (msg_strs[0] == i &&
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msg_strs[1] == j &&
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msg_strs[2])
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printf("%s ", msg_strs+2);
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else
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printf("%d:%d ", i, j);
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}
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e >>= 1;
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}
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}
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#else
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for (i = 0; i < NCAPINTS; i++) {
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u32 e = err_flags[i];
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for (j = 0; j < 32; j++) {
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if (e & 1)
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printf("%d:%d ", i, j);
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e >>= 1;
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}
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}
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#endif
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}
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int validate_cpu(void)
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{
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u32 *err_flags;
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int cpu_level, req_level;
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check_cpu(&cpu_level, &req_level, &err_flags);
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if (cpu_level < req_level) {
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printf("This kernel requires an %s CPU, ",
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cpu_name(req_level));
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printf("but only detected an %s CPU.\n",
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cpu_name(cpu_level));
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return -1;
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}
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if (err_flags) {
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puts("This kernel requires the following features "
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"not present on the CPU:\n");
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show_cap_strs(err_flags);
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putchar('\n');
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return -1;
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} else if (check_knl_erratum()) {
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return -1;
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} else {
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return 0;
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}
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}
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