mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 02:23:16 +00:00
c2ea2181db
Fix checkpatch warning: "WARNING: debugfs_remove_recursive(NULL) is safe this check is probably not required" Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
142 lines
3.3 KiB
C
142 lines
3.3 KiB
C
/* Inject a hwpoison memory failure on a arbitrary pfn */
|
|
#include <linux/module.h>
|
|
#include <linux/debugfs.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/hugetlb.h>
|
|
#include "internal.h"
|
|
|
|
static struct dentry *hwpoison_dir;
|
|
|
|
static int hwpoison_inject(void *data, u64 val)
|
|
{
|
|
unsigned long pfn = val;
|
|
struct page *p;
|
|
struct page *hpage;
|
|
int err;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (!pfn_valid(pfn))
|
|
return -ENXIO;
|
|
|
|
p = pfn_to_page(pfn);
|
|
hpage = compound_head(p);
|
|
/*
|
|
* This implies unable to support free buddy pages.
|
|
*/
|
|
if (!get_page_unless_zero(hpage))
|
|
return 0;
|
|
|
|
if (!hwpoison_filter_enable)
|
|
goto inject;
|
|
|
|
if (!PageLRU(p) && !PageHuge(p))
|
|
shake_page(p, 0);
|
|
/*
|
|
* This implies unable to support non-LRU pages.
|
|
*/
|
|
if (!PageLRU(p) && !PageHuge(p))
|
|
return 0;
|
|
|
|
/*
|
|
* do a racy check with elevated page count, to make sure PG_hwpoison
|
|
* will only be set for the targeted owner (or on a free page).
|
|
* We temporarily take page lock for try_get_mem_cgroup_from_page().
|
|
* memory_failure() will redo the check reliably inside page lock.
|
|
*/
|
|
lock_page(hpage);
|
|
err = hwpoison_filter(hpage);
|
|
unlock_page(hpage);
|
|
if (err)
|
|
return 0;
|
|
|
|
inject:
|
|
pr_info("Injecting memory failure at pfn %#lx\n", pfn);
|
|
return memory_failure(pfn, 18, MF_COUNT_INCREASED);
|
|
}
|
|
|
|
static int hwpoison_unpoison(void *data, u64 val)
|
|
{
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
return unpoison_memory(val);
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
|
|
DEFINE_SIMPLE_ATTRIBUTE(unpoison_fops, NULL, hwpoison_unpoison, "%lli\n");
|
|
|
|
static void pfn_inject_exit(void)
|
|
{
|
|
debugfs_remove_recursive(hwpoison_dir);
|
|
}
|
|
|
|
static int pfn_inject_init(void)
|
|
{
|
|
struct dentry *dentry;
|
|
|
|
hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
|
|
if (hwpoison_dir == NULL)
|
|
return -ENOMEM;
|
|
|
|
/*
|
|
* Note that the below poison/unpoison interfaces do not involve
|
|
* hardware status change, hence do not require hardware support.
|
|
* They are mainly for testing hwpoison in software level.
|
|
*/
|
|
dentry = debugfs_create_file("corrupt-pfn", 0200, hwpoison_dir,
|
|
NULL, &hwpoison_fops);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
dentry = debugfs_create_file("unpoison-pfn", 0200, hwpoison_dir,
|
|
NULL, &unpoison_fops);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
dentry = debugfs_create_u32("corrupt-filter-enable", 0600,
|
|
hwpoison_dir, &hwpoison_filter_enable);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
dentry = debugfs_create_u32("corrupt-filter-dev-major", 0600,
|
|
hwpoison_dir, &hwpoison_filter_dev_major);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
dentry = debugfs_create_u32("corrupt-filter-dev-minor", 0600,
|
|
hwpoison_dir, &hwpoison_filter_dev_minor);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
dentry = debugfs_create_u64("corrupt-filter-flags-mask", 0600,
|
|
hwpoison_dir, &hwpoison_filter_flags_mask);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
dentry = debugfs_create_u64("corrupt-filter-flags-value", 0600,
|
|
hwpoison_dir, &hwpoison_filter_flags_value);
|
|
if (!dentry)
|
|
goto fail;
|
|
|
|
#ifdef CONFIG_MEMCG_SWAP
|
|
dentry = debugfs_create_u64("corrupt-filter-memcg", 0600,
|
|
hwpoison_dir, &hwpoison_filter_memcg);
|
|
if (!dentry)
|
|
goto fail;
|
|
#endif
|
|
|
|
return 0;
|
|
fail:
|
|
pfn_inject_exit();
|
|
return -ENOMEM;
|
|
}
|
|
|
|
module_init(pfn_inject_init);
|
|
module_exit(pfn_inject_exit);
|
|
MODULE_LICENSE("GPL");
|