https://github.com/torvalds/linux
Revision b5b1404d0815894de0690de8a1ab58269e56eae6 authored by Linus Torvalds on 12 August 2018, 19:19:42 UTC, committed by Linus Torvalds on 12 August 2018, 19:19:42 UTC
This is purely a preparatory patch for upcoming changes during the 4.19 merge window. We have a function called "boot_cpu_state_init()" that isn't really about the bootup cpu state: that is done much earlier by the similarly named "boot_cpu_init()" (note lack of "state" in name). This function initializes some hotplug CPU state, and needs to run after the percpu data has been properly initialized. It even has a comment to that effect. Except it _doesn't_ actually run after the percpu data has been properly initialized. On x86 it happens to do that, but on at least arm and arm64, the percpu base pointers are initialized by the arch-specific 'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init(). This had some unexpected results, and in particular we have a patch pending for the merge window that did the obvious cleanup of using 'this_cpu_write()' in the cpu hotplug init code: - per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE; + this_cpu_write(cpuhp_state.state, CPUHP_ONLINE); which is obviously the right thing to do. Except because of the ordering issue, it actually failed miserably and unexpectedly on arm64. So this just fixes the ordering, and changes the name of the function to be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu hotplug state, because the core CPU state was supposed to have already been done earlier. Marked for stable, since the (not yet merged) patch that will show this problem is marked for stable. Reported-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent d6dd643
Tip revision: b5b1404d0815894de0690de8a1ab58269e56eae6 authored by Linus Torvalds on 12 August 2018, 19:19:42 UTC
init: rename and re-order boot_cpu_state_init()
init: rename and re-order boot_cpu_state_init()
Tip revision: b5b1404
fdtget.c
/*
* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
*
* Portions from U-Boot cmd_fdt.c (C) Copyright 2007
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
* Based on code written by:
* Pantelis Antoniou <pantelis.antoniou@gmail.com> and
* Matthew McClintock <msm@freescale.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <assert.h>
#include <ctype.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libfdt.h>
#include "util.h"
enum display_mode {
MODE_SHOW_VALUE, /* show values for node properties */
MODE_LIST_PROPS, /* list the properties for a node */
MODE_LIST_SUBNODES, /* list the subnodes of a node */
};
/* Holds information which controls our output and options */
struct display_info {
int type; /* data type (s/i/u/x or 0 for default) */
int size; /* data size (1/2/4) */
enum display_mode mode; /* display mode that we are using */
const char *default_val; /* default value if node/property not found */
};
static void report_error(const char *where, int err)
{
fprintf(stderr, "Error at '%s': %s\n", where, fdt_strerror(err));
}
/**
* Displays data of a given length according to selected options
*
* If a specific data type is provided in disp, then this is used. Otherwise
* we try to guess the data type / size from the contents.
*
* @param disp Display information / options
* @param data Data to display
* @param len Maximum length of buffer
* @return 0 if ok, -1 if data does not match format
*/
static int show_data(struct display_info *disp, const char *data, int len)
{
int i, size;
const uint8_t *p = (const uint8_t *)data;
const char *s;
int value;
int is_string;
char fmt[3];
/* no data, don't print */
if (len == 0)
return 0;
is_string = (disp->type) == 's' ||
(!disp->type && util_is_printable_string(data, len));
if (is_string) {
if (data[len - 1] != '\0') {
fprintf(stderr, "Unterminated string\n");
return -1;
}
for (s = data; s - data < len; s += strlen(s) + 1) {
if (s != data)
printf(" ");
printf("%s", (const char *)s);
}
return 0;
}
size = disp->size;
if (size == -1) {
size = (len % 4) == 0 ? 4 : 1;
} else if (len % size) {
fprintf(stderr, "Property length must be a multiple of "
"selected data size\n");
return -1;
}
fmt[0] = '%';
fmt[1] = disp->type ? disp->type : 'd';
fmt[2] = '\0';
for (i = 0; i < len; i += size, p += size) {
if (i)
printf(" ");
value = size == 4 ? fdt32_to_cpu(*(const uint32_t *)p) :
size == 2 ? (*p << 8) | p[1] : *p;
printf(fmt, value);
}
return 0;
}
/**
* List all properties in a node, one per line.
*
* @param blob FDT blob
* @param node Node to display
* @return 0 if ok, or FDT_ERR... if not.
*/
static int list_properties(const void *blob, int node)
{
const struct fdt_property *data;
const char *name;
int prop;
prop = fdt_first_property_offset(blob, node);
do {
/* Stop silently when there are no more properties */
if (prop < 0)
return prop == -FDT_ERR_NOTFOUND ? 0 : prop;
data = fdt_get_property_by_offset(blob, prop, NULL);
name = fdt_string(blob, fdt32_to_cpu(data->nameoff));
if (name)
puts(name);
prop = fdt_next_property_offset(blob, prop);
} while (1);
}
#define MAX_LEVEL 32 /* how deeply nested we will go */
/**
* List all subnodes in a node, one per line
*
* @param blob FDT blob
* @param node Node to display
* @return 0 if ok, or FDT_ERR... if not.
*/
static int list_subnodes(const void *blob, int node)
{
int nextoffset; /* next node offset from libfdt */
uint32_t tag; /* current tag */
int level = 0; /* keep track of nesting level */
const char *pathp;
int depth = 1; /* the assumed depth of this node */
while (level >= 0) {
tag = fdt_next_tag(blob, node, &nextoffset);
switch (tag) {
case FDT_BEGIN_NODE:
pathp = fdt_get_name(blob, node, NULL);
if (level <= depth) {
if (pathp == NULL)
pathp = "/* NULL pointer error */";
if (*pathp == '\0')
pathp = "/"; /* root is nameless */
if (level == 1)
puts(pathp);
}
level++;
if (level >= MAX_LEVEL) {
printf("Nested too deep, aborting.\n");
return 1;
}
break;
case FDT_END_NODE:
level--;
if (level == 0)
level = -1; /* exit the loop */
break;
case FDT_END:
return 1;
case FDT_PROP:
break;
default:
if (level <= depth)
printf("Unknown tag 0x%08X\n", tag);
return 1;
}
node = nextoffset;
}
return 0;
}
/**
* Show the data for a given node (and perhaps property) according to the
* display option provided.
*
* @param blob FDT blob
* @param disp Display information / options
* @param node Node to display
* @param property Name of property to display, or NULL if none
* @return 0 if ok, -ve on error
*/
static int show_data_for_item(const void *blob, struct display_info *disp,
int node, const char *property)
{
const void *value = NULL;
int len, err = 0;
switch (disp->mode) {
case MODE_LIST_PROPS:
err = list_properties(blob, node);
break;
case MODE_LIST_SUBNODES:
err = list_subnodes(blob, node);
break;
default:
assert(property);
value = fdt_getprop(blob, node, property, &len);
if (value) {
if (show_data(disp, value, len))
err = -1;
else
printf("\n");
} else if (disp->default_val) {
puts(disp->default_val);
} else {
report_error(property, len);
err = -1;
}
break;
}
return err;
}
/**
* Run the main fdtget operation, given a filename and valid arguments
*
* @param disp Display information / options
* @param filename Filename of blob file
* @param arg List of arguments to process
* @param arg_count Number of arguments
* @param return 0 if ok, -ve on error
*/
static int do_fdtget(struct display_info *disp, const char *filename,
char **arg, int arg_count, int args_per_step)
{
char *blob;
const char *prop;
int i, node;
blob = utilfdt_read(filename);
if (!blob)
return -1;
for (i = 0; i + args_per_step <= arg_count; i += args_per_step) {
node = fdt_path_offset(blob, arg[i]);
if (node < 0) {
if (disp->default_val) {
puts(disp->default_val);
continue;
} else {
report_error(arg[i], node);
return -1;
}
}
prop = args_per_step == 1 ? NULL : arg[i + 1];
if (show_data_for_item(blob, disp, node, prop))
return -1;
}
return 0;
}
static const char *usage_msg =
"fdtget - read values from device tree\n"
"\n"
"Each value is printed on a new line.\n\n"
"Usage:\n"
" fdtget <options> <dt file> [<node> <property>]...\n"
" fdtget -p <options> <dt file> [<node> ]...\n"
"Options:\n"
"\t-t <type>\tType of data\n"
"\t-p\t\tList properties for each node\n"
"\t-l\t\tList subnodes for each node\n"
"\t-d\t\tDefault value to display when the property is "
"missing\n"
"\t-h\t\tPrint this help\n\n"
USAGE_TYPE_MSG;
static void usage(const char *msg)
{
if (msg)
fprintf(stderr, "Error: %s\n\n", msg);
fprintf(stderr, "%s", usage_msg);
exit(2);
}
int main(int argc, char *argv[])
{
char *filename = NULL;
struct display_info disp;
int args_per_step = 2;
/* set defaults */
memset(&disp, '\0', sizeof(disp));
disp.size = -1;
disp.mode = MODE_SHOW_VALUE;
for (;;) {
int c = getopt(argc, argv, "d:hlpt:");
if (c == -1)
break;
switch (c) {
case 'h':
case '?':
usage(NULL);
case 't':
if (utilfdt_decode_type(optarg, &disp.type,
&disp.size))
usage("Invalid type string");
break;
case 'p':
disp.mode = MODE_LIST_PROPS;
args_per_step = 1;
break;
case 'l':
disp.mode = MODE_LIST_SUBNODES;
args_per_step = 1;
break;
case 'd':
disp.default_val = optarg;
break;
}
}
if (optind < argc)
filename = argv[optind++];
if (!filename)
usage("Missing filename");
argv += optind;
argc -= optind;
/* Allow no arguments, and silently succeed */
if (!argc)
return 0;
/* Check for node, property arguments */
if (args_per_step == 2 && (argc % 2))
usage("Must have an even number of arguments");
if (do_fdtget(&disp, filename, argv, argc, args_per_step))
return 1;
return 0;
}
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