KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 42 insertions, 0 deletions

diff --git a/Documentation/dev-tools/index.rst b/Documentation/dev-tools/index.rst
new file mode 100644
index 000000000..59cbb77b3
--- /dev/null
+++ b/Documentation/dev-tools/index.rst
@@ -0,0 +1,42 @@
+================================
+Development tools for the kernel
+================================
+
+This document is a collection of documents about development tools that can
+be used to work on the kernel. For now, the documents have been pulled
+together without any significant effort to integrate them into a coherent
+whole; patches welcome!
+
+A brief overview of testing-specific tools can be found in
+Documentation/dev-tools/testing-overview.rst
+
+Tools that are specific to debugging can be found in
+Documentation/process/debugging/index.rst
+
+.. toctree::
+   :caption: Table of contents
+   :maxdepth: 2
+
+   testing-overview
+   checkpatch
+   clang-format
+   coccinelle
+   context-analysis
+   sparse
+   kcov
+   gcov
+   kasan
+   kmsan
+   ubsan
+   kmemleak
+   kcsan
+   lkmm/index
+   kfence
+   kselftest
+   kunit/index
+   ktap
+   checkuapi
+   gpio-sloppy-logic-analyzer
+   autofdo
+   propeller
+   container