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authorJames Houghton <jthoughton@google.com>2022-10-18 20:01:25 +0000
committerAndrew Morton <akpm@linux-foundation.org>2022-11-08 15:57:22 -0800
commit8625147cafaa9ba74713d682f5185eb62cb2aedb (patch)
tree185342d7d161810419b46382581893ad93e46a22 /fs
parent120b116208a0877227fc82e3f0df81e7a3ed4ab1 (diff)
hugetlbfs: don't delete error page from pagecache
This change is very similar to the change that was made for shmem [1], and it solves the same problem but for HugeTLBFS instead. Currently, when poison is found in a HugeTLB page, the page is removed from the page cache. That means that attempting to map or read that hugepage in the future will result in a new hugepage being allocated instead of notifying the user that the page was poisoned. As [1] states, this is effectively memory corruption. The fix is to leave the page in the page cache. If the user attempts to use a poisoned HugeTLB page with a syscall, the syscall will fail with EIO, the same error code that shmem uses. For attempts to map the page, the thread will get a BUS_MCEERR_AR SIGBUS. [1]: commit a76054266661 ("mm: shmem: don't truncate page if memory failure happens") Link: https://lkml.kernel.org/r/20221018200125.848471-1-jthoughton@google.com Signed-off-by: James Houghton <jthoughton@google.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Tested-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: James Houghton <jthoughton@google.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs')
-rw-r--r--fs/hugetlbfs/inode.c13
1 files changed, 6 insertions, 7 deletions
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index dd54f67e47fd..df7772335dc0 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -328,6 +328,12 @@ static ssize_t hugetlbfs_read_iter(struct kiocb *iocb, struct iov_iter *to)
} else {
unlock_page(page);
+ if (PageHWPoison(page)) {
+ put_page(page);
+ retval = -EIO;
+ break;
+ }
+
/*
* We have the page, copy it to user space buffer.
*/
@@ -1111,13 +1117,6 @@ static int hugetlbfs_migrate_folio(struct address_space *mapping,
static int hugetlbfs_error_remove_page(struct address_space *mapping,
struct page *page)
{
- struct inode *inode = mapping->host;
- pgoff_t index = page->index;
-
- hugetlb_delete_from_page_cache(page);
- if (unlikely(hugetlb_unreserve_pages(inode, index, index + 1, 1)))
- hugetlb_fix_reserve_counts(inode);
-
return 0;
}