https://github.com/torvalds/linux
Revision d7f06bdd6ee87fbefa05af5f57361d85e7715b11 authored by Phil Auld on 06 September 2022, 20:35:42 UTC, committed by Greg Kroah-Hartman on 22 September 2022, 11:13:12 UTC
As PAGE_SIZE is unsigned long, -1 > PAGE_SIZE when NR_CPUS <= 3. This leads to very large file sizes: topology$ ls -l total 0 -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 core_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 core_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 core_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 core_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 core_siblings_list -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 die_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 die_cpus_list -r--r--r-- 1 root root 4096 Sep 5 11:59 die_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 package_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 package_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 physical_package_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 thread_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 thread_siblings_list Adjust the inequality to catch the case when NR_CPUS is configured to a small value. Fixes: 7ee951acd31a ("drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist") Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Yury Norov <yury.norov@gmail.com> Cc: stable@vger.kernel.org Cc: feng xiangjun <fengxj325@gmail.com> Reported-by: feng xiangjun <fengxj325@gmail.com> Signed-off-by: Phil Auld <pauld@redhat.com> Signed-off-by: Yury Norov <yury.norov@gmail.com> Link: https://lore.kernel.org/r/20220906203542.1796629-1-pauld@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 parent d8ab468
Tip revision: d7f06bdd6ee87fbefa05af5f57361d85e7715b11 authored by Phil Auld on 06 September 2022, 20:35:42 UTC
drivers/base: Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES
drivers/base: Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES
Tip revision: d7f06bd
backtracetest.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Simple stack backtrace regression test module
*
* (C) Copyright 2008 Intel Corporation
* Author: Arjan van de Ven <arjan@linux.intel.com>
*/
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/stacktrace.h>
static void backtrace_test_normal(void)
{
pr_info("Testing a backtrace from process context.\n");
pr_info("The following trace is a kernel self test and not a bug!\n");
dump_stack();
}
static DECLARE_COMPLETION(backtrace_work);
static void backtrace_test_irq_callback(unsigned long data)
{
dump_stack();
complete(&backtrace_work);
}
static DECLARE_TASKLET_OLD(backtrace_tasklet, &backtrace_test_irq_callback);
static void backtrace_test_irq(void)
{
pr_info("Testing a backtrace from irq context.\n");
pr_info("The following trace is a kernel self test and not a bug!\n");
init_completion(&backtrace_work);
tasklet_schedule(&backtrace_tasklet);
wait_for_completion(&backtrace_work);
}
#ifdef CONFIG_STACKTRACE
static void backtrace_test_saved(void)
{
unsigned long entries[8];
unsigned int nr_entries;
pr_info("Testing a saved backtrace.\n");
pr_info("The following trace is a kernel self test and not a bug!\n");
nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0);
stack_trace_print(entries, nr_entries, 0);
}
#else
static void backtrace_test_saved(void)
{
pr_info("Saved backtrace test skipped.\n");
}
#endif
static int backtrace_regression_test(void)
{
pr_info("====[ backtrace testing ]===========\n");
backtrace_test_normal();
backtrace_test_irq();
backtrace_test_saved();
pr_info("====[ end of backtrace testing ]====\n");
return 0;
}
static void exitf(void)
{
}
module_init(backtrace_regression_test);
module_exit(exitf);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
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