From 108bdff84a0b9104f05cb04a41bdd14f67f0d4c6 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Mon, 12 Nov 2018 18:55:24 +0100 Subject: [PATCH] efi_loader: correct efi_add_known_memory() If a memory bank is not EFI_PAGE_SIZE aligned efi_add_known_memory() the number of memory pages may be incorrectly calculated. We have to round up the start address and to round down the end address to determine which complete pages are provided by the memory bank. Signed-off-by: Heinrich Schuchardt Signed-off-by: Alexander Graf --- lib/efi_loader/efi_memory.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c index 1ffcf92eb2..f225a9028c 100644 --- a/lib/efi_loader/efi_memory.c +++ b/lib/efi_loader/efi_memory.c @@ -555,13 +555,21 @@ __weak void efi_add_known_memory(void) /* Add RAM */ for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) { - u64 ram_start = gd->bd->bi_dram[i].start; - u64 ram_size = gd->bd->bi_dram[i].size; - u64 start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK; - u64 pages = (ram_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT; + u64 ram_end, ram_start, pages; - efi_add_memory_map(start, pages, EFI_CONVENTIONAL_MEMORY, - false); + ram_start = gd->bd->bi_dram[i].start; + ram_end = ram_start + gd->bd->bi_dram[i].size; + + /* Remove partial pages */ + ram_end &= ~EFI_PAGE_MASK; + ram_start = (ram_start + EFI_PAGE_MASK) & ~EFI_PAGE_MASK; + + if (ram_end > ram_start) { + pages = (ram_end - ram_start) >> EFI_PAGE_SHIFT; + + efi_add_memory_map(ram_start, pages, + EFI_CONVENTIONAL_MEMORY, false); + } } } -- 2.39.5