Commit 6083fe74 authored by Mark Rutland's avatar Mark Rutland Committed by Catalin Marinas

arm64: respect mem= for EFI

When booting with EFI, we acquire the EFI memory map after parsing the
early params. This unfortuantely renders the option useless as we call
memblock_enforce_memory_limit (which uses memblock_remove_range behind
the scenes) before we've added any memblocks. We end up removing
nothing, then adding all of memory later when efi_init calls
reserve_regions.

Instead, we can log the limit and apply this later when we do the rest
of the memblock work in memblock_init, which should work regardless of
the presence of EFI. At the same time we may as well move the early
parameter into arm64's mm/init.c, close to arm64_memblock_init.

Any memory which must be mapped (e.g. for use by EFI runtime services)
must be mapped explicitly reather than relying on the linear mapping,
which may be truncated as a result of a mem= option passed on the kernel
command line.
Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Acked-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 7fe5d2b1
......@@ -322,25 +322,6 @@ static void __init setup_machine_fdt(phys_addr_t dt_phys)
dump_stack_set_arch_desc("%s (DT)", of_flat_dt_get_machine_name());
}
/*
* Limit the memory size that was specified via FDT.
*/
static int __init early_mem(char *p)
{
phys_addr_t limit;
if (!p)
return 1;
limit = memparse(p, &p) & PAGE_MASK;
pr_notice("Memory limited to %lldMB\n", limit >> 20);
memblock_enforce_memory_limit(limit);
return 0;
}
early_param("mem", early_mem);
static void __init request_standard_resources(void)
{
struct memblock_region *region;
......
......@@ -136,10 +136,29 @@ static void arm64_memory_present(void)
}
#endif
static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX;
/*
* Limit the memory size that was specified via FDT.
*/
static int __init early_mem(char *p)
{
if (!p)
return 1;
memory_limit = memparse(p, &p) & PAGE_MASK;
pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
return 0;
}
early_param("mem", early_mem);
void __init arm64_memblock_init(void)
{
phys_addr_t dma_phys_limit = 0;
memblock_enforce_memory_limit(memory_limit);
/*
* Register the kernel text, kernel data, initrd, and initial
* pagetables with memblock.
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment