[External] Re: [PATCH] riscv: add a warning when physical memory address overflows

[Palmer Dabbelt]

On Wed, 23 Oct 2024 07:25:22 PDT (-0700), punit.agrawal at bytedance.com wrote:
> Hi Palmer,
>
> [...]
>
>>> On 14/08/2024 08:26, Yunhui Cui wrote:
>>> > The part of physical memory that exceeds the size of the linear mapping
>>> > will be discarded. When the system starts up normally, a warning message
>>> > will be printed to prevent confusion caused by the mismatch between the
>>> > system memory and the actual physical memory.
>>> >
>>> > Signed-off-by: Yunhui Cui <cuiyunhui at bytedance.com>
>>> > ---
>>> >   arch/riscv/mm/init.c | 8 ++++++--
>>> >   1 file changed, 6 insertions(+), 2 deletions(-)
>>> >
>>> > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
>>> > index 52290c9bd04bd..c93164dc51658 100644
>>> > --- a/arch/riscv/mm/init.c
>>> > +++ b/arch/riscv/mm/init.c
>>> > @@ -236,8 +236,12 @@ static void __init setup_bootmem(void)
>>> >        */
>>> >       if (IS_ENABLED(CONFIG_64BIT)) {
>>> >               max_mapped_addr = __pa(PAGE_OFFSET) + KERN_VIRT_SIZE;
>>> > -             memblock_cap_memory_range(phys_ram_base,
>>> > -                                       max_mapped_addr - phys_ram_base);
>>> > +             if (memblock_end_of_DRAM() > max_mapped_addr) {
>>> > +                     memblock_cap_memory_range(phys_ram_base,
>>> > +                                               max_mapped_addr - phys_ram_base);
>>> > +                     pr_warn("Physical memory overflows the linear mapping size: region above 0x%llx removed",
>>> > +                             max_mapped_addr);
>>> > +             }
>>> >       }
>>> >
>>> >
>>>
>>>
>>> A bit weird to review and test my own patch, but here it is anyway :)
>>>
>>> Reviewed-by: Alexandre Ghiti <alexghiti at rivosinc.com>
>>>
>>> Tested-by: Alexandre Ghiti <alexghiti at rivosinc.com>
>
> Looks like the patch has been ready for a while now. If there are no
> further problems, can it be merged please?

It didn't build, I squashed in a 

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 8f8b76aaf99a..9641e4ad387f 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -259,8 +259,8 @@ static void __init setup_bootmem(void)
 		if (memblock_end_of_DRAM() > max_mapped_addr) {
 			memblock_cap_memory_range(phys_ram_base,
 						  max_mapped_addr - phys_ram_base);
-			pr_warn("Physical memory overflows the linear mapping size: region above 0x%llx removed",
-				max_mapped_addr);
+			pr_warn("Physical memory overflows the linear mapping size: region above %pa removed",
+				&max_mapped_addr);
 		}
 	}

to fix it.


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