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05 April 2024, 19:05:47 UTC
Revision 49275fef986abfb8b476e4708aaecc07e7d3e087 authored by Andy Lutomirski on 11 December 2017, 06:47:19 UTC, committed by Ingo Molnar on 22 December 2017, 19:13:01 UTC 
x86/vsyscall/64: Explicitly set _PAGE_USER in the pagetable hierarchy
 
The kernel is very erratic as to which pagetables have _PAGE_USER set.  The
vsyscall page gets lucky: it seems that all of the relevant pagetables are
among the apparently arbitrary ones that set _PAGE_USER.  Rather than
relying on chance, just explicitly set _PAGE_USER.

This will let us clean up pagetable setup to stop setting _PAGE_USER.  The
added code can also be reused by pagetable isolation to manage the
_PAGE_USER bit in the usermode tables.

[ tglx: Folded paravirt fix from Juergen Gross ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1 parent 146122e
Raw File
Tip revision: 49275fef986abfb8b476e4708aaecc07e7d3e087 authored by Andy Lutomirski on 11 December 2017, 06:47:19 UTC
x86/vsyscall/64: Explicitly set _PAGE_USER in the pagetable hierarchy
Tip revision: 49275fe
pm-notifier-error-inject.c 
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/suspend.h>

#include "notifier-error-inject.h"

static int priority;
module_param(priority, int, 0);
MODULE_PARM_DESC(priority, "specify PM notifier priority");

static struct notifier_err_inject pm_notifier_err_inject = {
	.actions = {
		{ NOTIFIER_ERR_INJECT_ACTION(PM_HIBERNATION_PREPARE) },
		{ NOTIFIER_ERR_INJECT_ACTION(PM_SUSPEND_PREPARE) },
		{ NOTIFIER_ERR_INJECT_ACTION(PM_RESTORE_PREPARE) },
		{}
	}
};

static struct dentry *dir;

static int err_inject_init(void)
{
	int err;

	dir = notifier_err_inject_init("pm", notifier_err_inject_dir,
					&pm_notifier_err_inject, priority);
	if (IS_ERR(dir))
		return PTR_ERR(dir);

	err = register_pm_notifier(&pm_notifier_err_inject.nb);
	if (err)
		debugfs_remove_recursive(dir);

	return err;
}

static void err_inject_exit(void)
{
	unregister_pm_notifier(&pm_notifier_err_inject.nb);
	debugfs_remove_recursive(dir);
}

module_init(err_inject_init);
module_exit(err_inject_exit);

MODULE_DESCRIPTION("PM notifier error injection module");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
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