Commit-ID: 24d7c494ce46d5bb6c8fd03e88a48ae249ec1492 Gitweb: http://git.kernel.org/tip/24d7c494ce46d5bb6c8fd03e88a48ae249ec1492 Author: Ard Biesheuvel <ard.biesheu...@linaro.org> AuthorDate: Tue, 4 Apr 2017 17:02:39 +0100 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Wed, 5 Apr 2017 12:27:24 +0200
efi/arm-stub: Round up FDT allocation to mapping size The FDT is mapped via a fixmap entry that is at least 2 MB in size and 2 MB aligned on 4 KB page size kernels. On UEFI systems, the FDT allocation may share this 2 MB mapping with a reserved region (or another memory region that we should never map), unless we account for this in the size of the allocation (the alignment is already 2 MB) So instead of taking guesses at the needed space, simply allocate 2 MB immediately. The allocation will be recorded as EFI_LOADER_DATA, and the kernel only memblock_reserve()'s the actual size of the FDT, so the unused space will be released back to the kernel. Reviewed-By: Jeffrey Hugo <jh...@codeaurora.org> Tested-by: Richard Ruigrok <rruig...@codeaurora.org> Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Matt Fleming <m...@codeblueprint.co.uk> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: linux-...@vger.kernel.org Link: http://lkml.kernel.org/r/20170404160245.27812-6-ard.biesheu...@linaro.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/arm64/include/asm/efi.h | 1 + drivers/firmware/efi/libstub/fdt.c | 57 ++++++++++++++++---------------------- 2 files changed, 25 insertions(+), 33 deletions(-) diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index 083a52d3..8f3043a 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -1,6 +1,7 @@ #ifndef _ASM_EFI_H #define _ASM_EFI_H +#include <asm/boot.h> #include <asm/cpufeature.h> #include <asm/io.h> #include <asm/mmu_context.h> diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c index 260c4b4..41f457b 100644 --- a/drivers/firmware/efi/libstub/fdt.c +++ b/drivers/firmware/efi/libstub/fdt.c @@ -206,6 +206,10 @@ static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg, return update_fdt_memmap(p->new_fdt_addr, map); } +#ifndef MAX_FDT_SIZE +#define MAX_FDT_SIZE SZ_2M +#endif + /* * Allocate memory for a new FDT, then add EFI, commandline, and * initrd related fields to the FDT. This routine increases the @@ -233,7 +237,6 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table, u32 desc_ver; unsigned long mmap_key; efi_memory_desc_t *memory_map, *runtime_map; - unsigned long new_fdt_size; efi_status_t status; int runtime_entry_count = 0; struct efi_boot_memmap map; @@ -262,41 +265,29 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table, "Exiting boot services and installing virtual address map...\n"); map.map = &memory_map; + status = efi_high_alloc(sys_table, MAX_FDT_SIZE, EFI_FDT_ALIGN, + new_fdt_addr, max_addr); + if (status != EFI_SUCCESS) { + pr_efi_err(sys_table, + "Unable to allocate memory for new device tree.\n"); + goto fail; + } + /* - * Estimate size of new FDT, and allocate memory for it. We - * will allocate a bigger buffer if this ends up being too - * small, so a rough guess is OK here. + * Now that we have done our final memory allocation (and free) + * we can get the memory map key needed for exit_boot_services(). */ - new_fdt_size = fdt_size + EFI_PAGE_SIZE; - while (1) { - status = efi_high_alloc(sys_table, new_fdt_size, EFI_FDT_ALIGN, - new_fdt_addr, max_addr); - if (status != EFI_SUCCESS) { - pr_efi_err(sys_table, "Unable to allocate memory for new device tree.\n"); - goto fail; - } - - status = update_fdt(sys_table, - (void *)fdt_addr, fdt_size, - (void *)*new_fdt_addr, new_fdt_size, - cmdline_ptr, initrd_addr, initrd_size); + status = efi_get_memory_map(sys_table, &map); + if (status != EFI_SUCCESS) + goto fail_free_new_fdt; - /* Succeeding the first time is the expected case. */ - if (status == EFI_SUCCESS) - break; + status = update_fdt(sys_table, (void *)fdt_addr, fdt_size, + (void *)*new_fdt_addr, MAX_FDT_SIZE, cmdline_ptr, + initrd_addr, initrd_size); - if (status == EFI_BUFFER_TOO_SMALL) { - /* - * We need to allocate more space for the new - * device tree, so free existing buffer that is - * too small. - */ - efi_free(sys_table, new_fdt_size, *new_fdt_addr); - new_fdt_size += EFI_PAGE_SIZE; - } else { - pr_efi_err(sys_table, "Unable to construct new device tree.\n"); - goto fail_free_new_fdt; - } + if (status != EFI_SUCCESS) { + pr_efi_err(sys_table, "Unable to construct new device tree.\n"); + goto fail_free_new_fdt; } priv.runtime_map = runtime_map; @@ -340,7 +331,7 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table, pr_efi_err(sys_table, "Exit boot services failed.\n"); fail_free_new_fdt: - efi_free(sys_table, new_fdt_size, *new_fdt_addr); + efi_free(sys_table, MAX_FDT_SIZE, *new_fdt_addr); fail: sys_table->boottime->free_pool(runtime_map);
