From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001
From: Zeng Chi <zengchi@kylinos.cn>
Date: Mon, 21 Sep 2026 18:24:42 +0800
Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL
 attributes

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>
---
 arch/mips/mm/physaddr.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 arch/mips/mm/physaddr.c

(limited to 'arch/mips/mm/physaddr.c')

diff --git a/arch/mips/mm/physaddr.c b/arch/mips/mm/physaddr.c
new file mode 100644
index 000000000..a6b1bf820
--- /dev/null
+++ b/arch/mips/mm/physaddr.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/mmdebug.h>
+#include <linux/mm.h>
+
+#include <asm/addrspace.h>
+#include <asm/sections.h>
+#include <asm/io.h>
+#include <asm/page.h>
+#include <asm/dma.h>
+
+static inline bool __debug_virt_addr_valid(unsigned long x)
+{
+	/*
+	 * MAX_DMA_ADDRESS is a virtual address that may not correspond to an
+	 * actual physical address. Enough code relies on
+	 * virt_to_phys(MAX_DMA_ADDRESS) that we just need to work around it
+	 * and always return true.
+	 */
+	if (x == MAX_DMA_ADDRESS)
+		return true;
+
+	return x >= PAGE_OFFSET && (KSEGX(x) < KSEG2 ||
+	       IS_ENABLED(CONFIG_EVA) ||
+	       !IS_ENABLED(CONFIG_HIGHMEM));
+}
+
+phys_addr_t __virt_to_phys(volatile const void *x)
+{
+	WARN(!__debug_virt_addr_valid((unsigned long)x),
+	     "virt_to_phys used for non-linear address: %p (%pS)\n",
+	     x, x);
+
+	return __virt_to_phys_nodebug(x);
+}
+EXPORT_SYMBOL(__virt_to_phys);
+
+phys_addr_t __phys_addr_symbol(unsigned long x)
+{
+	/* This is bounds checking against the kernel image only.
+	 * __pa_symbol should only be used on kernel symbol addresses.
+	 */
+	VIRTUAL_BUG_ON(x < (unsigned long)_text ||
+		       x > (unsigned long)_end);
+
+	return __pa_symbol_nodebug(x);
+}
+EXPORT_SYMBOL(__phys_addr_symbol);
-- 
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