docs: add 0.0.26 release highlights

Signed-off-by: Omar Sandoval <osandov@osandov.com>

docs/release_highlights.rst

@@ -6,6 +6,7 @@ from the full `release notes <https://github.com/osandov/drgn/releases>`_.
 
 .. toctree::
 
+   release_highlights/0.0.26.rst
    release_highlights/0.0.25.rst
    release_highlights/0.0.24.rst
    release_highlights/0.0.23.rst

docs/release_highlights/0.0.26.rst

@@ -0,0 +1,100 @@
+0.0.26 (Released March 11th, 2024)
+====================================
+
+These are some of the highlights of drgn 0.0.26. See the `GitHub release
+<https://github.com/osandov/drgn/releases/tag/v0.0.26>`_ for the full release
+notes, including more improvements and bug fixes.
+
+.. highlight:: pycon
+
+Miscellaneous Helpers
+---------------------
+
+This release added several new Linux kernel helpers with no particular theme:
+
+- :func:`~drgn.helpers.linux.printk.print_dmesg()`, a shortcut for printing the
+  kernel log buffer.
+- :func:`~drgn.helpers.linux.idr.idr_for_each_entry()`, a shortcut for
+  iterating over an IDR and casting its entries to a specific type.
+- :func:`~drgn.helpers.linux.stackdepot.stack_depot_fetch()` for getting stack
+  traces from the storage used by KASAN and other kernel debugging tools. This
+  was contributed by Peter Collingbourne.
+- :func:`~drgn.helpers.linux.plist.plist_head_empty()`,
+  :func:`~drgn.helpers.linux.plist.plist_node_empty()`,
+  :func:`~drgn.helpers.linux.plist.plist_first_entry()`,
+  :func:`~drgn.helpers.linux.plist.plist_last_entry()`,
+  :func:`~drgn.helpers.linux.plist.plist_for_each()`, and
+  :func:`~drgn.helpers.linux.plist.plist_for_each_entry()`, helpers for working
+  with the kernel's priority-sorted lists.
+
+``fsrefs.py`` Tool
+------------------
+
+The ``fsrefs.py`` tool was added to the ``tools`` directory. It prints
+information about everything that is referencing a file or filesystem. This is
+similar to :manpage:`fuser(1)` and :manpage:`lsof(8)`, but it can find more
+since it has access to kernel internals.
+
+.. code-block:: console
+
+    $ ./tools/fsrefs.py --inode /dev/urandom
+    pid 1349 (bluetoothd) fd 16 (struct file *)0xffff8881458cf000
+    pid 1368 (udisksd) fd 15 (struct file *)0xffff888145c13100
+    ...
+    $ ./tools/fsrefs.py --super-block /run
+    mount /run (struct mount *)0xffff8881015cc140
+    pid 1 (systemd) fd 256 (struct file *)0xffff8881012f3d00 /run/initctl
+    pid 1 (systemd) fd 380 (struct file *)0xffff88810bf88800 /run/dmeventd-server
+    pid 1 (systemd) fd 385 (struct file *)0xffff88810bf88f00 /run/dmeventd-client
+    mount /run (mount namespace 4026532545) (struct mount *)0xffff8881474028c0
+    pid 2135770 (systemd-journal) vma 0x7f7d94f2a000-0x7f7d94f2b000 (struct file *)0xffff88813925bf00 /run/systemd/journal/kernel-seqnum
+    pid 2135770 (systemd-journal) vma 0x7f7d94f2b000-0x7f7d94f2c000 (struct file *)0xffff88813925a100 /run/systemd/journal/seqnum
+    ...
+
+``fsrefs.py`` currently checks:
+
+- File descriptors
+- Task working directories
+- Task root directories
+- Memory mappings
+- Filesystem mounts
+- `binfmt_misc <https://docs.kernel.org/admin-guide/binfmt-misc.html>`_
+- :manpage:`loop(4)` devices
+- Swap files
+- `uprobes <https://docs.kernel.org/trace/uprobetracer.html>`_
+
+It will be extended to check more as the need arises, so feel free to report
+anything it missed.
+
+(Note that as opposed to the ``contrib`` directory, scripts in the ``tools``
+directory are regularly maintained and tested.)
+
+DWARF Package Files
+-------------------
+
+drgn now supports split DWARF package (.dwp) files. These are generated by the
+``dwp`` and ``llvm-dwp`` tools.
+
+Linux 6.8 Support
+-----------------
+
+Linux 6.8 changed some filesystem internals in a way that broke a couple of
+drgn helpers. Here are some errors you might see with older versions of drgn
+that are fixed in this release.
+
+From :func:`~drgn.helpers.linux.fs.path_lookup()` or
+:func:`~drgn.helpers.linux.fs.for_each_mount()` (fixed by Johannes Thumshirn)::
+
+    AttributeError: 'struct mnt_namespace' has no member 'list'
+
+From :func:`~drgn.helpers.linux.fs.path_lookup()`::
+
+    AttributeError: 'struct dentry' has no member 'd_subdirs'
+
+Python 3.13 Support
+-------------------
+
+Python 3.13, currently in alpha, removed or changed some private APIs
+(``_PyDict_GetItemIdWithError()``, ``_PyDict_SetItemId()``, and
+``_PyLong_AsByteArray()``) that drgn depended on, which caused build failures.
+This was fixed by using public APIs instead.