From:   Alexandre Ghiti <alexghiti@rivosinc.com>
To:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Mike Rapoport <rppt@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Anup Patel <anup@brainfault.org>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org, devicetree@vger.kernel.org,
        linux-mm@kvack.org
Cc:     Alexandre Ghiti <alexghiti@rivosinc.com>
Subject: [PATCH v7 3/4] arm64: Make use of memblock_isolate_memory for the linear mapping
Date:   Fri, 10 Mar 2023 10:45:38 +0100
Message-Id: <20230310094539.764357-4-alexghiti@rivosinc.com>
In-Reply-To: <20230310094539.764357-1-alexghiti@rivosinc.com>
References: <20230310094539.764357-1-alexghiti@rivosinc.com>
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In order to isolate the kernel text mapping, we used some sort of hack
to isolate the kernel text range which consisted in marking this region
as not mappable with memblock_mark_nomap. Simply use the newly introduced
memblock_isolate_memory function which does exactly the same but does not
uselessly mark the region as not mappable.

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
---
 arch/arm64/mm/mmu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 6f9d8898a025..408dc852805c 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -552,7 +552,7 @@ static void __init map_mem(pgd_t *pgdp)
 	 * So temporarily mark them as NOMAP to skip mappings in
 	 * the following for-loop
 	 */
-	memblock_mark_nomap(kernel_start, kernel_end - kernel_start);
+	memblock_isolate_memory(kernel_start, kernel_end - kernel_start);
 
 #ifdef CONFIG_KEXEC_CORE
 	if (crash_mem_map) {
@@ -568,6 +568,7 @@ static void __init map_mem(pgd_t *pgdp)
 	for_each_mem_range(i, &start, &end) {
 		if (start >= end)
 			break;
+
 		/*
 		 * The linear map must allow allocation tags reading/writing
 		 * if MTE is present. Otherwise, it has the same attributes as
@@ -589,7 +590,6 @@ static void __init map_mem(pgd_t *pgdp)
 	 */
 	__map_memblock(pgdp, kernel_start, kernel_end,
 		       PAGE_KERNEL, NO_CONT_MAPPINGS);
-	memblock_clear_nomap(kernel_start, kernel_end - kernel_start);
 
 	/*
 	 * Use page-level mappings here so that we can shrink the region
-- 
2.37.2