Re: 2.6.0-test4: Unable to handle kernel NULL pointer dereference

[Andrew Morton]

Christopher Swingley <cswingle@xxxxxxxxxxxx> wrote:
>
> kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000
> ...
> kernel: EIP is at find_inode_fast+0x1a/0x60
> ...
> model name	: AMD Athlon(tm) XP 1800+
> ...

You've been bitten by the athlon-prefetch(0)-goes-oops problem.

Nobody seems to be working this, so I'll be sending the below in to Linus.

--- 25/include/asm-i386/processor.h~disable-athlon-prefetch	2003-08-23 13:48:16.000000000 -0700
+++ 25-akpm/include/asm-i386/processor.h	2003-08-23 13:48:16.000000000 -0700
@@ -578,6 +578,8 @@ static inline void rep_nop(void)
 #define ARCH_HAS_PREFETCH
 extern inline void prefetch(const void *x)
 {
+	if (cpu_data[0].x86_vendor == X86_VENDOR_AMD)
+		return;
 	alternative_input(ASM_NOP4,
 			  "prefetchnta (%1)",
 			  X86_FEATURE_XMM,

_

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