[syslinux] [PATCH 9/9] Workaround for a buggy get info BIOS

[H. Peter Anvin]

Details on the affected machine?

Frediano Ziglio <frediano.ziglio at citrix.com> wrote:

>This issue drive parameters only one time to avoid to have disk read
>failure.
>This happened just on a specific machine, probably the BIOS is buggy
>but
>the fix didn't have any regression.
>
>Signed-off-by: Frediano Ziglio <frediano.ziglio at citrix.com>
>---
> core/adv.inc |   35 ++++++++++++++++++-----------------
> 1 files changed, 18 insertions(+), 17 deletions(-)
>
>diff --git a/core/adv.inc b/core/adv.inc
>index a714800..ab29fde 100644
>--- a/core/adv.inc
>+++ b/core/adv.inc
>@@ -351,6 +351,23 @@ adv_read_write:
> 		jne .noedd
> 		test cl,1
> 		jz .noedd
>+
>+		push 512
>+		sub sp, 14h
>+		push 0
>+		push 1ah
>+		mov si,sp
>+		mov ah,48h			; EDD get drive parameters
>+		mov dl,[ADVDrive]
>+		push ds
>+		push ss
>+		pop ds
>+		int 13h
>+		pop ds
>+		add sp,18h
>+		pop ax
>+		mov [ADVSsz], ax
>+
> 		mov si,.ebios
> .noedd:
> 
>@@ -375,23 +392,6 @@ adv_read_write:
> 
> 		extern xfer_buf_seg
> .ebios:
>-		pusha
>-		sub sp,1ch
>-		push 1eh
>-		mov si,sp
>-		mov ah,48h			; EDD get drive parameters
>-		mov dl,[ADVDrive]
>-		push ds
>-		push ss
>-		pop ds
>-		mov word [si+18h], 512
>-		int 13h
>-		mov ax, [si+18h]
>-		pop ds
>-		mov [ADVSsz], ax
>-		add sp,1eh
>-		popa
>-
> 		mov cx,adv_retries
> .eb_retry:
> 		; Form DAPA on stack
>@@ -450,6 +450,7 @@ adv_read_write:
> 		; copy it back
> 		pusha
> 		push ds
>+		cld
> 		mov si, di
> 		mov di, bx
> 		push xfer_buf_seg

-- 
Sent from my mobile phone. Please excuse brevity and lack of formatting.