diff options
| author | Miaohe Lin <linmiaohe@huawei.com> | 2025-09-04 14:22:58 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-09-21 14:22:21 -0700 |
| commit | 5ce1dbfdd8e3d4dca2f842dd833ca7e264ace85b (patch) | |
| tree | c3ba2fef38bf2ea19a4598e9ed9b5e0d731beb76 /mm/hwpoison-inject.c | |
| parent | a488ba3124c82d704963fcd760fe653df1987b13 (diff) | |
| download | net-next-5ce1dbfdd8e3d4dca2f842dd833ca7e264ace85b.tar.gz | |
mm/hwpoison: decouple hwpoison_filter from mm/memory-failure.c
mm/memory-failure.c defines and uses hwpoison_filter_* parameters but the
values of those parameters can only be modified via mm/hwpoison-inject.c
from userspace. They have a potentially different life time. Decouple
those parameters from mm/memory-failure.c to fix this broken layering.
Link: https://lkml.kernel.org/r/20250904062258.3336092-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/hwpoison-inject.c')
| -rw-r--r-- | mm/hwpoison-inject.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index 7ecaa1900137d2..a11222572f9789 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -7,8 +7,96 @@ #include <linux/swap.h> #include <linux/pagemap.h> #include <linux/hugetlb.h> +#include <linux/page-flags.h> +#include <linux/memcontrol.h> #include "internal.h" +static u32 hwpoison_filter_enable; +static u32 hwpoison_filter_dev_major = ~0U; +static u32 hwpoison_filter_dev_minor = ~0U; +static u64 hwpoison_filter_flags_mask; +static u64 hwpoison_filter_flags_value; + +static int hwpoison_filter_dev(struct page *p) +{ + struct folio *folio = page_folio(p); + struct address_space *mapping; + dev_t dev; + + if (hwpoison_filter_dev_major == ~0U && + hwpoison_filter_dev_minor == ~0U) + return 0; + + mapping = folio_mapping(folio); + if (mapping == NULL || mapping->host == NULL) + return -EINVAL; + + dev = mapping->host->i_sb->s_dev; + if (hwpoison_filter_dev_major != ~0U && + hwpoison_filter_dev_major != MAJOR(dev)) + return -EINVAL; + if (hwpoison_filter_dev_minor != ~0U && + hwpoison_filter_dev_minor != MINOR(dev)) + return -EINVAL; + + return 0; +} + +static int hwpoison_filter_flags(struct page *p) +{ + if (!hwpoison_filter_flags_mask) + return 0; + + if ((stable_page_flags(p) & hwpoison_filter_flags_mask) == + hwpoison_filter_flags_value) + return 0; + else + 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_MEMCG +static u64 hwpoison_filter_memcg; +static int hwpoison_filter_task(struct page *p) +{ + if (!hwpoison_filter_memcg) + return 0; + + if (page_cgroup_ino(p) != hwpoison_filter_memcg) + return -EINVAL; + + return 0; +} +#else +static int hwpoison_filter_task(struct page *p) { return 0; } +#endif + +static int hwpoison_filter(struct page *p) +{ + if (!hwpoison_filter_enable) + return 0; + + if (hwpoison_filter_dev(p)) + return -EINVAL; + + if (hwpoison_filter_flags(p)) + return -EINVAL; + + if (hwpoison_filter_task(p)) + return -EINVAL; + + return 0; +} + static struct dentry *hwpoison_dir; static int hwpoison_inject(void *data, u64 val) @@ -67,6 +155,7 @@ DEFINE_DEBUGFS_ATTRIBUTE(unpoison_fops, NULL, hwpoison_unpoison, "%lli\n"); static void __exit pfn_inject_exit(void) { hwpoison_filter_enable = 0; + hwpoison_filter_unregister(); debugfs_remove_recursive(hwpoison_dir); } @@ -105,6 +194,8 @@ static int __init pfn_inject_init(void) &hwpoison_filter_memcg); #endif + hwpoison_filter_register(hwpoison_filter); + return 0; } |