9c5938694c
Unfortunately, vm_insert_page() and friends and up passing driver-allocated folios into folio_add_file_rmap_pte() using insert_page_into_pte_locked(). While these driver-allocated folios can be compound pages (large folios), they are not proper "rmappable" folios. In these VM_MIXEDMAP VMAs, there isn't really the concept of a reverse mapping, so long-term, we should clean that up and not call into rmap code. For the time being, document how we can end up in rmap code with large folios that are not marked rmappable. Link: https://lkml.kernel.org/r/793c5cee-d5fc-4eb1-86a2-39e05686233d@redhat.com Fixes: 68f0320824fa ("mm/rmap: convert folio_add_file_rmap_range() into folio_add_file_rmap_[pte|ptes|pmd]()") Reported-by: syzbot+50ef73537bbc393a25bb@syzkaller.appspotmail.com Closes: https://lkml.kernel.org/r/000000000000014174060e09316e@google.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yin Fengwei <fengwei.yin@intel.com> 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.