RISC-V: ACPI: fix early_ioremap to early_memremap

When SVPBMT is enabled, __acpi_map_table() will directly access the
data in DDR through the IO attribute, rather than through hardware
cache consistency, resulting in incorrect data in the obtained ACPI
table.

The log: ACPI: [ACPI:0x18] Invalid zero length.

We do not assume whether the bootloader flushes or not. We should
access in a cacheable way instead of maintaining cache consistency
by software.

Fixes: 3b426d4b5b14 ("RISC-V: ACPI : Fix for usage of pointers in different address space")
Cc: stable@vger.kernel.org
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
Link: https://lore.kernel.org/r/20241014130141.86426-1-cuiyunhui@bytedance.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/arch/riscv/kernel/acpi.c b/arch/riscv/kernel/acpi.c
index 6e0d333f57e556912742e4282a6dcb03674ebb2d..2fd29695a788f25fe7392be5b4e844c223a0ba68 100644 (file)
--- a/arch/riscv/kernel/acpi.c
+++ b/arch/riscv/kernel/acpi.c
@@ -210,7 +210,7 @@ void __init __iomem *__acpi_map_table(unsigned long phys, unsigned long size)
        if (!size)
                return NULL;
 
-       return early_ioremap(phys, size);
+       return early_memremap(phys, size);
 }
 
 void __init __acpi_unmap_table(void __iomem *map, unsigned long size)
@@ -218,7 +218,7 @@ void __init __acpi_unmap_table(void __iomem *map, unsigned long size)
        if (!map || !size)
                return;
 
-       early_iounmap(map, size);
+       early_memunmap(map, size);
 }
 
 void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size)