This issue can be seen on 32bit operation when one of E820_RAM type entries is greater than 4GB memory space.
The efi_alloc() finds a free memory in the conventional memory which is greater than 4GB. But, it does type cast to 32bit address space and eventually returns invalid address.
Signed-off-by: Aiden Park aiden.park@intel.com --- arch/x86/lib/e820.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/arch/x86/lib/e820.c b/arch/x86/lib/e820.c index d6ae2c4e9d..3e93931231 100644 --- a/arch/x86/lib/e820.c +++ b/arch/x86/lib/e820.c @@ -41,11 +41,15 @@ void efi_add_known_memory(void) { struct e820_entry e820[E820MAX]; unsigned int i, num; - u64 start, pages; + u64 start, pages, ram_top; int type;
num = install_e820_map(ARRAY_SIZE(e820), e820);
+ ram_top = (u64)gd->ram_top & ~EFI_PAGE_MASK; + if (!ram_top) + ram_top = 0x100000000ULL; + for (i = 0; i < num; ++i) { start = e820[i].addr; pages = ALIGN(e820[i].size, EFI_PAGE_SIZE) >> EFI_PAGE_SHIFT; @@ -70,6 +74,22 @@ void efi_add_known_memory(void) }
efi_add_memory_map(start, pages, type, false); + + if (type == EFI_CONVENTIONAL_MEMORY) { + u64 end = start + (pages << EFI_PAGE_SHIFT); + + /* reserve the memory region greater than ram_top */ + if (ram_top < start) { + efi_add_memory_map(start, pages, + EFI_BOOT_SERVICES_DATA, + true); + } else if (start < ram_top && ram_top < end) { + pages = (end - ram_top) >> EFI_PAGE_SHIFT; + efi_add_memory_map(ram_top, pages, + EFI_BOOT_SERVICES_DATA, + true); + } + } } } #endif /* CONFIG_IS_ENABLED(EFI_LOADER) */