[RFC PATCH 5/7] riscv: Align the sv39 linear map to 16 GiB
From: Samuel Holland <samuel.holland@sifive.com>
Date: 2024-08-14 08:56:29
Also in:
linux-riscv, lkml, llvm
Subsystem:
documentation, risc-v architecture, the rest · Maintainers:
Jonathan Corbet, Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
The KASAN implementation on RISC-V requires the shadow memory for the vmemmap and linear map regions to be aligned to a PMD boundary (1 GiB). For KASAN_GENERIC (KASAN_SHADOW_SCALE_SHIFT == 3), this enforces 8 GiB alignment for the memory regions themselves. KASAN_SW_TAGS uses 16-byte granules (KASAN_SHADOW_SCALE_SHIFT == 4), so now the memory regions must be aligned to a 16 GiB boundary. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> --- Documentation/arch/riscv/vm-layout.rst | 10 +++++----- arch/riscv/include/asm/page.h | 2 +- 2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/Documentation/arch/riscv/vm-layout.rst b/Documentation/arch/riscv/vm-layout.rst
index 077b968dcc81..ed71b3b1b784 100644
--- a/Documentation/arch/riscv/vm-layout.rst
+++ b/Documentation/arch/riscv/vm-layout.rst@@ -47,11 +47,11 @@ RISC-V Linux Kernel SV39 | Kernel-space virtual memory, shared between all processes: ____________________________________________________________|___________________________________________________________ | | | | - ffffffc4fea00000 | -236 GB | ffffffc4feffffff | 6 MB | fixmap - ffffffc4ff000000 | -236 GB | ffffffc4ffffffff | 16 MB | PCI io - ffffffc500000000 | -236 GB | ffffffc5ffffffff | 4 GB | vmemmap - ffffffc600000000 | -232 GB | ffffffd5ffffffff | 64 GB | vmalloc/ioremap space - ffffffd600000000 | -168 GB | fffffff5ffffffff | 128 GB | direct mapping of all physical memory + ffffffc2fea00000 | -244 GB | ffffffc2feffffff | 6 MB | fixmap + ffffffc2ff000000 | -244 GB | ffffffc2ffffffff | 16 MB | PCI io + ffffffc300000000 | -244 GB | ffffffc3ffffffff | 4 GB | vmemmap + ffffffc400000000 | -240 GB | ffffffd3ffffffff | 64 GB | vmalloc/ioremap space + ffffffd400000000 | -176 GB | fffffff3ffffffff | 128 GB | direct mapping of all physical memory | | | | fffffff700000000 | -36 GB | fffffffeffffffff | 32 GB | kasan __________________|____________|__________________|_________|____________________________________________________________
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
index 7ede2111c591..09d15567b0b8 100644
--- a/arch/riscv/include/asm/page.h
+++ b/arch/riscv/include/asm/page.h@@ -37,7 +37,7 @@ * define the PAGE_OFFSET value for SV48 and SV39. */ #define PAGE_OFFSET_L4 _AC(0xffffaf8000000000, UL) -#define PAGE_OFFSET_L3 _AC(0xffffffd600000000, UL) +#define PAGE_OFFSET_L3 _AC(0xffffffd400000000, UL) #else #define PAGE_OFFSET _AC(CONFIG_PAGE_OFFSET, UL) #endif /* CONFIG_64BIT */
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2.45.1