https://github.com/torvalds/linux
Revision 5f32b265400de723ab0db23101a75ac073bdd980 authored by Jérôme Glisse on 31 August 2017, 21:17:38 UTC, committed by Linus Torvalds on 31 August 2017, 23:13:00 UTC
The invalidate_page callback suffered from two pitfalls. First it used to happen after the page table lock was release and thus a new page might have setup before the call to invalidate_page() happened. This is in a weird way fixed by commit c7ab0d2fdc84 ("mm: convert try_to_unmap_one() to use page_vma_mapped_walk()") that moved the callback under the page table lock but this also broke several existing users of the mmu_notifier API that assumed they could sleep inside this callback. The second pitfall was invalidate_page() being the only callback not taking a range of address in respect to invalidation but was giving an address and a page. Lots of the callback implementers assumed this could never be THP and thus failed to invalidate the appropriate range for THP. By killing this callback we unify the mmu_notifier callback API to always take a virtual address range as input. Finally this also simplifies the end user life as there is now two clear choices: - invalidate_range_start()/end() callback (which allow you to sleep) - invalidate_range() where you can not sleep but happen right after page table update under page table lock Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Bernhard Held <berny156@gmx.de> Cc: Adam Borowski <kilobyte@angband.pl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Wanpeng Li <kernellwp@gmail.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: axie <axie@amd.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent fb1522e
Tip revision: 5f32b265400de723ab0db23101a75ac073bdd980 authored by Jérôme Glisse on 31 August 2017, 21:17:38 UTC
mm/mmu_notifier: kill invalidate_page
mm/mmu_notifier: kill invalidate_page
Tip revision: 5f32b26
kmemleak-test.c
/*
* mm/kmemleak-test.c
*
* Copyright (C) 2008 ARM Limited
* Written by Catalin Marinas <catalin.marinas@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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
*/
#define pr_fmt(fmt) "kmemleak: " fmt
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/list.h>
#include <linux/percpu.h>
#include <linux/fdtable.h>
#include <linux/kmemleak.h>
struct test_node {
long header[25];
struct list_head list;
long footer[25];
};
static LIST_HEAD(test_list);
static DEFINE_PER_CPU(void *, kmemleak_test_pointer);
/*
* Some very simple testing. This function needs to be extended for
* proper testing.
*/
static int __init kmemleak_test_init(void)
{
struct test_node *elem;
int i;
pr_info("Kmemleak testing\n");
/* make some orphan objects */
pr_info("kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
pr_info("kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
pr_info("kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
pr_info("kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
pr_info("kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
pr_info("kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
pr_info("kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
pr_info("kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
#ifndef CONFIG_MODULES
pr_info("kmem_cache_alloc(files_cachep) = %p\n",
kmem_cache_alloc(files_cachep, GFP_KERNEL));
pr_info("kmem_cache_alloc(files_cachep) = %p\n",
kmem_cache_alloc(files_cachep, GFP_KERNEL));
#endif
pr_info("vmalloc(64) = %p\n", vmalloc(64));
pr_info("vmalloc(64) = %p\n", vmalloc(64));
pr_info("vmalloc(64) = %p\n", vmalloc(64));
pr_info("vmalloc(64) = %p\n", vmalloc(64));
pr_info("vmalloc(64) = %p\n", vmalloc(64));
/*
* Add elements to a list. They should only appear as orphan
* after the module is removed.
*/
for (i = 0; i < 10; i++) {
elem = kzalloc(sizeof(*elem), GFP_KERNEL);
pr_info("kzalloc(sizeof(*elem)) = %p\n", elem);
if (!elem)
return -ENOMEM;
INIT_LIST_HEAD(&elem->list);
list_add_tail(&elem->list, &test_list);
}
for_each_possible_cpu(i) {
per_cpu(kmemleak_test_pointer, i) = kmalloc(129, GFP_KERNEL);
pr_info("kmalloc(129) = %p\n",
per_cpu(kmemleak_test_pointer, i));
}
return 0;
}
module_init(kmemleak_test_init);
static void __exit kmemleak_test_exit(void)
{
struct test_node *elem, *tmp;
/*
* Remove the list elements without actually freeing the
* memory.
*/
list_for_each_entry_safe(elem, tmp, &test_list, list)
list_del(&elem->list);
}
module_exit(kmemleak_test_exit);
MODULE_LICENSE("GPL");
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