Re: [PATCH] arm64/efi: fix grub_efi_get_ram_base()

[Steve McIntyre]

On Thu, Feb 21, 2019 at 10:15:08AM +0000, Leif Lindholm wrote:
>grub_efi_get_ram_base() looks for the lowest available RAM address by
>traversing the memory map, comparing lowest address found so far.
>Due to a brain glitch, that "so far" was initialized to GRUB_UINT_MAX -
>completely preventing boot on systems without RAM below 4GB.
>
>Change the initial value to GRUB_EFI_MAX_USABLE_ADDRESS, as originally
>intended.
>
>Reported-by: Steve McIntyre <address@hidden>
>Signed-off-by: Leif Lindholm <address@hidden>

Tested-by: Steve McIntyre <address@hidden>

>---
> grub-core/kern/efi/mm.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/grub-core/kern/efi/mm.c b/grub-core/kern/efi/mm.c
>index 42ad7c570..cfe9764b7 100644
>--- a/grub-core/kern/efi/mm.c
>+++ b/grub-core/kern/efi/mm.c
>@@ -653,7 +653,7 @@ grub_efi_get_ram_base(grub_addr_t *base_addr)
>   if (ret < 1)
>     return GRUB_ERR_BUG;
> 
>-  for (desc = memory_map, *base_addr = GRUB_UINT_MAX;
>+  for (desc = memory_map, *base_addr = GRUB_EFI_MAX_USABLE_ADDRESS;
>        (grub_addr_t) desc < ((grub_addr_t) memory_map + memory_map_size);
>        desc = NEXT_MEMORY_DESCRIPTOR (desc, desc_size))
>     if (desc->attribute & GRUB_EFI_MEMORY_WB)
>-- 
>2.11.0
>
>
-- 
Steve McIntyre, Cambridge, UK.                                address@hidden
"I've only once written 'SQL is my bitch' in a comment. But that code 
 is in use on a military site..." -- Simon Booth