From 1f88e9c8eaef91db510739b451a6837102a87f60 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Wed, 25 Jul 2012 14:32:37 +0100 Subject: [PATCH] [romprefix] Round up PMM allocation sizes to nearest 4kB Some AMI BIOSes apparently break in exciting ways when asked for PMM allocations for sizes that are not multiples of 4kB. Fix by rounding up the image source area to the nearest 4kB. (The temporary decompression area is already rounded up to the nearest 128kB, to facilitate sharing between multiple iPXE ROMs.) Reported-by: Itay Gazit Signed-off-by: Michael Brown --- src/arch/i386/prefix/romprefix.S | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/arch/i386/prefix/romprefix.S b/src/arch/i386/prefix/romprefix.S index 2b4c20b8..35d037ef 100644 --- a/src/arch/i386/prefix/romprefix.S +++ b/src/arch/i386/prefix/romprefix.S @@ -352,9 +352,13 @@ pmm_scan: call print_message /* We have PMM and so a 1kB stack: preserve whole registers */ pushal - /* Allocate image source PMM block */ + /* Allocate image source PMM block. Round up the size to the + * nearest 4kB (8 512-byte sectors) to work around AMI BIOS bugs. + */ movzbl romheader_size, %ecx addw extra_size, %cx + addw $0x0007, %cx /* Round up to multiple of 8 512-byte sectors */ + andw $0xfff8, %cx shll $5, %ecx movl $PMM_HANDLE_BASE_IMAGE_SOURCE, %ebx movw $get_pmm_image_source, %bp