Attachment 195991 Details for Bug 239585 – Proposed patch for testing

[patch] Proposed patch for testing

edd-maxdrive.patch (text/plain), 1.04 KB, created by H. Peter Anvin on 2007-09-14 16:01:38 UTC

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Creator: H. Peter Anvin

Created: 2007-09-14 16:01:38 UTC

Size: 1.04 KB

patch

obsolete

>diff --git a/arch/i386/boot/edd.c b/arch/i386/boot/edd.c
>index bd138e4..fad5f6b 100644
>--- a/arch/i386/boot/edd.c
>+++ b/arch/i386/boot/edd.c
>@@ -129,7 +129,7 @@ void query_edd(void)
> 	char eddarg[8];
> 	int do_mbr = 1;
> 	int do_edd = 1;
>-	int devno;
>+	int devno, maxdrive;
> 	struct edd_info ei, *edp;
> 	u32 *mbrptr;
> 
>@@ -145,8 +145,22 @@ void query_edd(void)
> 
> 	if (!do_edd)
> 		return;
>-
>-	for (devno = 0x80; devno < 0x80+EDD_MBR_SIG_MAX; devno++) {
>+	
>+	/* Query the number of drives.  This prevents the probe
>+	   from wandering into CD-ROMs and nonexistent devices;
>+	   some machines have been known to hang if nonexistent
>+	   devices are probed.
>+
>+	   Ralf Brown (inter61) seems to imply that BIOS location
>+	   40:75 is more reliable than the return value from INT 13h,
>+	   AH=08h, so go with that. */
>+
>+	set_fs(0);
>+	maxdrive = rdfs8(0x475)|0x80;
>+	if (maxdrive > 0x80+EDD_MBR_SIG_MAX)
>+		maxdrive = 0x80+EDD_MBR_SIG_MAX;
>+
>+	for (devno = 0x80; devno < maxdrive; devno++) {
> 		/*
> 		 * Scan the BIOS-supported hard disks and query EDD
> 		 * information...

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Attachments on bug 239585: 195991 | 200511 | 200531