19d3e22180
has_extra_refcount() makes the assumption that the page cache adds a ref count of 1 and subtracts this in the extra_pins case. Commit a08c7193e4f1 (mm/filemap: remove hugetlb special casing in filemap.c) modifies __filemap_add_folio() by calling folio_ref_add(folio, nr); for all cases (including hugtetlb) where nr is the number of pages in the folio. We should adjust the number of references coming from the page cache by subtracing the number of pages rather than 1. In hugetlbfs_read_iter(), folio_test_has_hwpoisoned() is testing the wrong flag as, in the hugetlb case, memory-failure code calls folio_test_set_hwpoison() to indicate poison. folio_test_hwpoison() is the correct function to test for that flag. After these fixes, the hugetlb hwpoison read selftest passes all cases. Link: https://lkml.kernel.org/r/20240112180840.367006-1-sidhartha.kumar@oracle.com Fixes: a08c7193e4f1 ("mm/filemap: remove hugetlb special casing in filemap.c") Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Closes: https://lore.kernel.org/linux-mm/20230713001833.3778937-1-jiaqiyan@google.com/T/#m8e1469119e5b831bbd05d495f96b842e4a1c5519 Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Acked-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: James Houghton <jthoughton@google.com> Cc: Jiaqi Yan <jiaqiyan@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: <stable@vger.kernel.org> [6.7+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.