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From: Dave Peterson <dsp@llnl.gov>
To: linux-kernel@vger.kernel.org
Subject: [PATCH] fix bug in x86_64 csum_partial_copy_generic()
Date: Fri, 29 Jul 2005 16:32:19 -0700
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I was observing reproducible crashes on the "movw %bx,(%rsi)" instruction
below while a process in a recvfrom() system call was copying packet data
to user space.  The patch below fixes the exception table and causes the
crash to no longer reproduce.  Please apply.

Thanks,
Dave Peterson
<dsp@llnl.gov> <dave_peterson@pobox.com>

diff -urNp -X dontdiff linux-2.6.12.3/arch/x86_64/lib/csum-copy.S linux-2.6.12.3-bugfix/arch/x86_64/lib/csum-copy.S
--- linux-2.6.12.3/arch/x86_64/lib/csum-copy.S	2005-07-15 14:18:57.000000000 -0700
+++ linux-2.6.12.3-bugfix/arch/x86_64/lib/csum-copy.S	2005-07-29 16:06:47.000000000 -0700
@@ -188,8 +188,8 @@ csum_partial_copy_generic:
 	source
 	movw (%rdi),%bx
 	adcl %ebx,%eax
-	dest
 	decl %ecx
+	dest
 	movw %bx,(%rsi)
 	leaq 2(%rdi),%rdi
 	leaq 2(%rsi),%rsi