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Message-ID: <tencent_97F6C19BAF7C99B22BB1199FE16B266C2B07@qq.com>
From:   Woody Zhang <woodylab@foxmail.com>
To:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Alexandre Ghiti <alexghiti@rivosinc.com>,
        Conor Dooley <conor.dooley@microchip.com>
Cc:     linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        Woody Zhang <woodylab@foxmail.com>
Subject: [PATCH v2] riscv: move memblock_allow_resize() after linear mapping is ready
Date:   Mon, 12 Jun 2023 17:37:38 +0800
MIME-Version: 1.0
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The initial memblock metadata is accessed from kernel image mapping. The
regions arrays need to "reallocated" from memblock and accessed through
linear mapping to cover more memblock regions. So the resizing should
not be allowed until linear mapping is ready. Note that there are
memblock allocations when building linear mapping.

This patch is similar to 24cc61d8cb5a ("arm64: memblock: don't permit
memblock resizing until linear mapping is up").

Fixes: 671f9a3e2e24 ("RISC-V: Setup initial page tables in two stages")
Signed-off-by: Woody Zhang <woodylab@foxmail.com>
---
Changes in v2:
 - Refine commit log

---
 arch/riscv/mm/init.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 4fa420faa780..57874f89dce2 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -267,7 +267,6 @@ static void __init setup_bootmem(void)
 	dma_contiguous_reserve(dma32_phys_limit);
 	if (IS_ENABLED(CONFIG_64BIT))
 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
-	memblock_allow_resize();
 }
 
 #ifdef CONFIG_MMU
@@ -1284,6 +1283,9 @@ static void __init setup_vm_final(void)
 	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
 	local_flush_tlb_all();
 
+	/* Depend on that Linear Mapping is ready */
+	memblock_allow_resize();
+
 	pt_ops_set_late();
 }
 #else
-- 
2.39.2