Re: [PATCH] riscv: mm: fix wrong phys_ram_base value for RV64

From: Alexandre ghiti
Date: Thu Dec 02 2021 - 10:52:19 EST


On 12/2/21 16:36, Jisheng Zhang wrote:
Currently, if 64BIT and !XIP_KERNEL, the phys_ram_base is always 0,
no matter the real start of dram reported by memblock is. The original
patch[1] is correct, I believe it's not corrected merged due to lots
of #ifdef in arch/riscv/mm/init.c, I plan to send a clean up series
soon.

[1] http://lists.infradead.org/pipermail/linux-riscv/2021-July/007650.html

Fixes: 6d7f91d914bc ("riscv: Get rid of CONFIG_PHYS_RAM_BASE in kernel physical address conversion")
Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
---
arch/riscv/mm/init.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 24b2b8044602..3c0649dba4ff 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -187,10 +187,10 @@ static void __init setup_bootmem(void)
phys_ram_end = memblock_end_of_DRAM();
-#ifndef CONFIG_64BIT
#ifndef CONFIG_XIP_KERNEL
phys_ram_base = memblock_start_of_DRAM();
#endif
+#ifndef CONFIG_64BIT
/*
* memblock allocator is not aware of the fact that last 4K bytes of
* the addressable memory can not be mapped because of IS_ERR_VALUE


Good catch, you can add:

Reviewed-by: Alexandre Ghiti <alex@xxxxxxxx>

And looking forward to your cleanup patch ;)

Thanks,

Alex