From 6083fe74b7bfffc2c7be8c711596608bda0cda6e Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 15 Jan 2015 16:42:14 +0000 Subject: [PATCH] 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: Mark Rutland Acked-by: Catalin Marinas Acked-by: Ard Biesheuvel Tested-by: Ard Biesheuvel Cc: Leif Lindholm Cc: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kernel/setup.c | 19 ------------------- arch/arm64/mm/init.c | 19 +++++++++++++++++++ 2 files changed, 19 insertions(+), 19 deletions(-) diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 199d1b7809d7..207413fe08a0 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -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; diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index bac492c12fcc..11c7b701b681 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -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. -- 2.20.1