Re: [PATCH v2 1/3] riscv: Add support for mem=

[Nikolay Borisov]

On 15.02.20 Ð. 13:49 Ñ., Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> 
> This sets a memory limit provided via mem=3D on the command line,
> analogously to many other architectures.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> =2D--
>  arch/riscv/mm/init.c | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 965a8cf4829c..aec39a56d6cf 100644
> =2D-- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -118,6 +118,23 @@ static void __init setup_initrd(void)
>  }
>  #endif /* CONFIG_BLK_DEV_INITRD */
> 
> +static phys_addr_t memory_limit =3D PHYS_ADDR_MAX;

3d is the ascii code for =, meaning your client is somehow br0ken?
> +
> +/*
> + * Limit the memory size that was specified via FDT.
> + */
> +static int __init early_mem(char *p)
> +{
> +	if (!p)
> +		return 1;
> +
> +	memory_limit =3D memparse(p, &p) & PAGE_MASK;

ditto

> +	pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
> +
> +	return 0;
> +}
> +early_param("mem", early_mem);
> +
>  static phys_addr_t dtb_early_pa __initdata;
> 
>  void __init setup_bootmem(void)
> @@ -127,6 +144,8 @@ void __init setup_bootmem(void)
>  	phys_addr_t vmlinux_end =3D __pa_symbol(&_end);
>  	phys_addr_t vmlinux_start =3D __pa_symbol(&_start);
> 
> +	memblock_enforce_memory_limit(memory_limit);
> +
>  	/* Find the memory region containing the kernel */
>  	for_each_memblock(memory, reg) {
>  		phys_addr_t end =3D reg->base + reg->size;
> =2D-
> 2.16.4
> 
>