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, 57 insertions, 0 deletions

diff --git a/drivers/firmware/imx/Kconfig b/drivers/firmware/imx/Kconfig
new file mode 100644
index 000000000..127ad752a
--- /dev/null
+++ b/drivers/firmware/imx/Kconfig
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config IMX_DSP
+	tristate "IMX DSP Protocol driver"
+	depends on IMX_MBOX
+	help
+	  This enables DSP IPC protocol between host AP (Linux)
+	  and the firmware running on DSP.
+	  DSP exists on some i.MX8 processors (e.g i.MX8QM, i.MX8QXP).
+
+	  It acts like a doorbell. Client might use shared memory to
+	  exchange information with DSP side.
+
+config IMX_SCU
+	bool "IMX SCU Protocol driver"
+	depends on IMX_MBOX
+	select SOC_BUS
+	help
+	  The System Controller Firmware (SCFW) is a low-level system function
+	  which runs on a dedicated Cortex-M core to provide power, clock, and
+	  resource management. It exists on some i.MX8 processors. e.g. i.MX8QM
+	  (QM, QP), and i.MX8QX (QXP, DX).
+
+	  This driver manages the IPC interface between host CPU and the
+	  SCU firmware running on M4.
+
+config IMX_SCMI_CPU_DRV
+	tristate "IMX SCMI CPU Protocol driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	default y if ARCH_MXC
+	help
+	  The System Controller Management Interface firmware (SCMI FW) is
+	  a low-level system function which runs on a dedicated Cortex-M
+	  core that could provide cpu management features.
+
+	  This driver can also be built as a module.
+
+config IMX_SCMI_LMM_DRV
+	tristate "IMX SCMI LMM Protocol driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	default y if ARCH_MXC
+	help
+	  The System Controller Management Interface firmware (SCMI FW) is
+	  a low-level system function which runs on a dedicated Cortex-M
+	  core that could provide Logical Machine management features.
+
+	  This driver can also be built as a module.
+
+config IMX_SCMI_MISC_DRV
+	tristate "IMX SCMI MISC Protocol driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	default y if ARCH_MXC
+	help
+	  The System Controller Management Interface firmware (SCMI FW) is
+	  a low-level system function which runs on a dedicated Cortex-M
+	  core that could provide misc functions such as board control.
+
+	  This driver can also be built as a module.