On 2024-04-16 Björn Töpel wrote: > Nam Cao <namcao@xxxxxxxxxxxxx> writes: > > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > > index fa34cf55037b..f600cfee0aef 100644 > > --- a/arch/riscv/mm/init.c > > +++ b/arch/riscv/mm/init.c > > @@ -197,7 +197,6 @@ early_param("mem", early_mem); > > static void __init setup_bootmem(void) > > { > > phys_addr_t vmlinux_end = __pa_symbol(&_end); > > - phys_addr_t max_mapped_addr; > > phys_addr_t phys_ram_end, vmlinux_start; > > > > if (IS_ENABLED(CONFIG_XIP_KERNEL)) > > @@ -238,17 +237,9 @@ static void __init setup_bootmem(void) > > /* > > * 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 > > - * macro. Make sure that last 4k bytes are not usable by memblock > > - * if end of dram is equal to maximum addressable memory. For 64-bit > > - * kernel, this problem can't happen here as the end of the virtual > > - * address space is occupied by the kernel mapping then this check must > > - * be done as soon as the kernel mapping base address is determined. > > + * macro. Make sure that last 4k bytes are not usable by memblock. > > */ > > - if (!IS_ENABLED(CONFIG_64BIT)) { > > - max_mapped_addr = __pa(~(ulong)0); > > - if (max_mapped_addr == (phys_ram_end - 1)) > > - memblock_set_current_limit(max_mapped_addr - 4096); > > - } > > + memblock_reserve(__pa(-PAGE_SIZE), PAGE_SIZE); > > > > min_low_pfn = PFN_UP(phys_ram_base); > > max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); > > Nice! Would you mind submitting this as a proper fix (unless there's a > way to do it non-arch specific like Matthew pointed out). I don't mind, but I am waiting for the discussion on the non-arch solution. Best regards, Nam