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, 23 insertions, 0 deletions

diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug
new file mode 100644
index 000000000..265c44610
--- /dev/null
+++ b/arch/arm64/Kconfig.debug
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config PID_IN_CONTEXTIDR
+	bool "Write the current PID to the CONTEXTIDR register"
+	help
+	  Enabling this option causes the kernel to write the current PID to
+	  the CONTEXTIDR register, at the expense of some additional
+	  instructions during context switch. Say Y here only if you are
+	  planning to use hardware trace tools with this kernel.
+
+config DEBUG_EFI
+	depends on EFI && DEBUG_INFO
+	bool "UEFI debugging"
+	help
+	  Enable this option to include EFI specific debugging features into
+	  the kernel that are only useful when using a debug build of the
+	  UEFI firmware
+
+config ARM64_RELOC_TEST
+	depends on m
+	tristate "Relocation testing module"
+
+source "drivers/hwtracing/coresight/Kconfig"