mirror of
https://github.com/torvalds/linux.git
synced 2024-12-30 06:41:43 +00:00
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>
102 lines
2.1 KiB
C
102 lines
2.1 KiB
C
/* -*- linux-c -*- ------------------------------------------------------- *
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
* Copyright 2007-2008 rPath, Inc. - All Rights Reserved
|
|
*
|
|
* This file is part of the Linux kernel, and is made available under
|
|
* the terms of the GNU General Public License version 2.
|
|
*
|
|
* ----------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* arch/x86/boot/cpu.c
|
|
*
|
|
* Check for obligatory CPU features and abort if the features are not
|
|
* present.
|
|
*/
|
|
|
|
#include "boot.h"
|
|
#ifdef CONFIG_X86_FEATURE_NAMES
|
|
#include "cpustr.h"
|
|
#endif
|
|
|
|
static char *cpu_name(int level)
|
|
{
|
|
static char buf[6];
|
|
|
|
if (level == 64) {
|
|
return "x86-64";
|
|
} else {
|
|
if (level == 15)
|
|
level = 6;
|
|
sprintf(buf, "i%d86", level);
|
|
return buf;
|
|
}
|
|
}
|
|
|
|
static void show_cap_strs(u32 *err_flags)
|
|
{
|
|
int i, j;
|
|
#ifdef CONFIG_X86_FEATURE_NAMES
|
|
const unsigned char *msg_strs = (const unsigned char *)x86_cap_strs;
|
|
for (i = 0; i < NCAPINTS; i++) {
|
|
u32 e = err_flags[i];
|
|
for (j = 0; j < 32; j++) {
|
|
if (msg_strs[0] < i ||
|
|
(msg_strs[0] == i && msg_strs[1] < j)) {
|
|
/* Skip to the next string */
|
|
msg_strs += 2;
|
|
while (*msg_strs++)
|
|
;
|
|
}
|
|
if (e & 1) {
|
|
if (msg_strs[0] == i &&
|
|
msg_strs[1] == j &&
|
|
msg_strs[2])
|
|
printf("%s ", msg_strs+2);
|
|
else
|
|
printf("%d:%d ", i, j);
|
|
}
|
|
e >>= 1;
|
|
}
|
|
}
|
|
#else
|
|
for (i = 0; i < NCAPINTS; i++) {
|
|
u32 e = err_flags[i];
|
|
for (j = 0; j < 32; j++) {
|
|
if (e & 1)
|
|
printf("%d:%d ", i, j);
|
|
e >>= 1;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
int validate_cpu(void)
|
|
{
|
|
u32 *err_flags;
|
|
int cpu_level, req_level;
|
|
|
|
check_cpu(&cpu_level, &req_level, &err_flags);
|
|
|
|
if (cpu_level < req_level) {
|
|
printf("This kernel requires an %s CPU, ",
|
|
cpu_name(req_level));
|
|
printf("but only detected an %s CPU.\n",
|
|
cpu_name(cpu_level));
|
|
return -1;
|
|
}
|
|
|
|
if (err_flags) {
|
|
puts("This kernel requires the following features "
|
|
"not present on the CPU:\n");
|
|
show_cap_strs(err_flags);
|
|
putchar('\n');
|
|
return -1;
|
|
} else if (check_knl_erratum()) {
|
|
return -1;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|