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, 28 insertions, 0 deletions

diff --git a/drivers/firmware/tegra/Kconfig b/drivers/firmware/tegra/Kconfig
new file mode 100644
index 000000000..3a9162706
--- /dev/null
+++ b/drivers/firmware/tegra/Kconfig
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menu "Tegra firmware driver"
+
+config TEGRA_IVC
+	bool
+	depends on ARCH_TEGRA
+	help
+	  IVC (Inter-VM Communication) protocol is part of the IPC
+	  (Inter Processor Communication) framework on Tegra. It maintains the
+	  data and the different communication channels in SysRAM or RAM and
+	  keeps the content is synchronization between host CPU and remote
+	  processors.
+
+config TEGRA_BPMP
+	bool "Tegra BPMP driver"
+	depends on ARCH_TEGRA && TEGRA_HSP_MBOX
+	depends on !CPU_BIG_ENDIAN
+	select TEGRA_IVC
+	help
+	  BPMP (Boot and Power Management Processor) is designed to off-loading
+	  the PM functions which include clock/DVFS/thermal/power from the CPU.
+	  It needs HSP as the HW synchronization and notification module and
+	  IVC module as the message communication protocol.
+
+	  This driver manages the IPC interface between host CPU and the
+	  firmware running on BPMP.
+
+endmenu