Re: Regression in 2.6.23-pre Was: Problems with 2.6.23-rc6 on AMDGeode LX800

[H. Peter Anvin]

Jordan Crouse wrote:
> 
> Its the latter - max_pfn as read by find_max_pfn() in arch/i386/e820.c
> is being set to 9F (640k) in the broken case, this due to the
> the e820 map looking something like this:
> 
> Address   Size      Type
> 00000000  0009FC00  1
> 0009FC00  00000400  2
> 000E0000  00002000  2
> 
> (Yep, thats it - thats the list.  e820.nr_map is indeed 3). 
> 
> Long story short, bdata->node_low_pfn gets set to 9F, and When we 
> try to allocate the bootmem bitmap (at _pa_symbol(_text), which is 
> page 0x100), then the system gets appropriately angry.
> 
> As background, I'm using syslinux 3.36 as my loader here - I've used this
> exact same version for a very long time, so I don't blame it in the least.
> Something is getting confused in the early kernel, and whatever that
> something is, a still unknown change in a newer version of the BIOS
> fixed it.  The search goes on.
> 

Please try the following debug patch to let us know what is going on.

	-hpa
diff --git a/arch/i386/boot/memory.c b/arch/i386/boot/memory.c
index 1a2e62d..a0ccf29 100644
--- a/arch/i386/boot/memory.c
+++ b/arch/i386/boot/memory.c
@@ -33,6 +33,12 @@ static int detect_memory_e820(void)
 		      "=m" (*desc)
 		    : "D" (desc), "a" (0xe820));
 
+		printf("e820: err %d id 0x%08x next %u %08x:%08x %u\n",
+		       err, id, next,
+		       (unsigned int)desc->addr,
+		       (unsigned int)desc->size,
+		       desc->type);
+
 		if (err || id != SMAP)
 			break;