diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 71d05f481727669ce88a517a3cd631988fd9c32b..766abdab94e70b939233f2fdc62be70275a9f3de 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1363,6 +1363,11 @@ running once the system is up. reserve= [KNL,BUGS] Force the kernel to ignore some iomem area + reservetop= [IA-32] + Format: nn[KMG] + Reserves a hole at the top of the kernel virtual + address space. + resume= [SWSUSP] Specify the partition device for software suspend diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c index 060c68004bec876c4f249292b93ebcc21f1caaf0..16d99444cf66653c446e59534cc9f8e9f704643a 100644 --- a/arch/i386/kernel/setup.c +++ b/arch/i386/kernel/setup.c @@ -934,6 +934,24 @@ static void __init parse_cmdline_early (char ** cmdline_p) } } +/* + * reservetop=size reserves a hole at the top of the kernel address space which + * a hypervisor can load into later. Needed for dynamically loaded hypervisors, + * so relocating the fixmap can be done before paging initialization. + */ +static int __init parse_reservetop(char *arg) +{ + unsigned long address; + + if (!arg) + return -EINVAL; + + address = memparse(arg, &arg); + reserve_top_address(address); + return 0; +} +early_param("reservetop", parse_reservetop); + /* * Callback for efi_memory_walk. */