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Linux kernel source tree
ab73b29efd
Currently, starting a PV VM on an iomap-based filesystem with large folio support, such as XFS, will not work. We'll be stuck in unpack_one()->gmap_make_secure(), because we can't seem to make progress splitting the large folio. The problem is that we require a writable PTE but a writable PTE under such filesystems will imply a dirty folio. So whenever we have a writable PTE, we'll have a dirty folio, and dirty iomap folios cannot currently get split, because split_folio()->split_huge_page_to_list_to_order()->filemap_release_folio() will fail in iomap_release_folio(). So we will not make any progress splitting such large folios. Until dirty folios can be split more reliably, let's manually trigger writeback of the problematic folio using filemap_write_and_wait_range(), and retry the split immediately afterwards exactly once, before looking up the folio again. Should this logic be part of split_folio()? Likely not; most split users don't have to split so eagerly to make any progress. For now, this seems to affect xfs, zonefs and erofs, and this patch makes it work again (tested on xfs only). While this could be considered a fix for commit |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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 reStructuredText 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.