diff options
| -rw-r--r-- | Documentation/vm/hwpoison.txt | 16 | ||||
| -rw-r--r-- | mm/hwpoison-inject.c | 7 | ||||
| -rw-r--r-- | mm/internal.h | 1 | ||||
| -rw-r--r-- | mm/memory-failure.c | 46 |
4 files changed, 70 insertions, 0 deletions
diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt index f454d3cd4d6..989e5afe740 100644 --- a/Documentation/vm/hwpoison.txt +++ b/Documentation/vm/hwpoison.txt @@ -123,6 +123,22 @@ Only handle memory failures to pages associated with the file system defined by block device major/minor. -1U is the wildcard value. This should be only used for testing with artificial injection. +corrupt-filter-memcg + +Limit injection to pages owned by memgroup. Specified by inode number +of the memcg. + +Example: + mkdir /cgroup/hwpoison + + usemem -m 100 -s 1000 & + echo `jobs -p` > /cgroup/hwpoison/tasks + + memcg_ino=$(ls -id /cgroup/hwpoison | cut -f1 -d' ') + echo $memcg_ino > /debug/hwpoison/corrupt-filter-memcg + + page-types -p `pidof init` --hwpoison # shall do nothing + page-types -p `pidof usemem` --hwpoison # poison its pages corrupt-filter-flags-mask corrupt-filter-flags-value diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index c4dfd89f654..c838735ac31 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -112,6 +112,13 @@ static int pfn_inject_init(void) if (!dentry) goto fail; +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_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(); diff --git a/mm/internal.h b/mm/internal.h index b2027c73119..5a6761bea6a 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -257,3 +257,4 @@ extern u32 hwpoison_filter_dev_major; extern u32 hwpoison_filter_dev_minor; extern u64 hwpoison_filter_flags_mask; extern u64 hwpoison_filter_flags_value; +extern u64 hwpoison_filter_memcg; diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 22d2b2028e5..117ef159846 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -100,6 +100,49 @@ static int hwpoison_filter_flags(struct page *p) return -EINVAL; } +/* + * This allows stress tests to limit test scope to a collection of tasks + * by putting them under some memcg. This prevents killing unrelated/important + * processes such as /sbin/init. Note that the target task may share clean + * pages with init (eg. libc text), which is harmless. If the target task + * share _dirty_ pages with another task B, the test scheme must make sure B + * is also included in the memcg. At last, due to race conditions this filter + * can only guarantee that the page either belongs to the memcg tasks, or is + * a freed page. + */ +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP +u64 hwpoison_filter_memcg; +EXPORT_SYMBOL_GPL(hwpoison_filter_memcg); +static int hwpoison_filter_task(struct page *p) +{ + struct mem_cgroup *mem; + struct cgroup_subsys_state *css; + unsigned long ino; + + if (!hwpoison_filter_memcg) + return 0; + + mem = try_get_mem_cgroup_from_page(p); + if (!mem) + return -EINVAL; + + css = mem_cgroup_css(mem); + /* root_mem_cgroup has NULL dentries */ + if (!css->cgroup->dentry) + return -EINVAL; + + ino = css->cgroup->dentry->d_inode->i_ino; + css_put(css); + + if (ino != hwpoison_filter_memcg) + return -EINVAL; + + return 0; +} +#else +static int hwpoison_filter_task(struct page *p) { return 0; } +#endif + int hwpoison_filter(struct page *p) { if (hwpoison_filter_dev(p)) @@ -108,6 +151,9 @@ int hwpoison_filter(struct page *p) if (hwpoison_filter_flags(p)) return -EINVAL; + if (hwpoison_filter_task(p)) + return -EINVAL; + return 0; } EXPORT_SYMBOL_GPL(hwpoison_filter); |