Re: [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@xxxxxxxxxxxxx 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@xxxxxxxxxxxxx>
> > > > ---
> > > >   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@xxxxxxxxxxxx>
> > >
> > > Tested-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>
>
> 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.


> [...]