From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: qemu-kvm-1.1.0 crashing with kernel 3.5.0-rc6
Date: Sun, 29 Jul 2012 19:34:50 +0300
Message-ID: <5015662A.2000006@redhat.com>
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Cc: Eric Northup <digitaleric@google.com>, kvm@vger.kernel.org,
	Gleb Natapov <gleb@redhat.com>,
	Jan Kiszka <jan.kiszka@siemens.com>
To: Chris Clayton <chris2553@googlemail.com>
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On 07/29/2012 06:47 PM, Avi Kivity wrote:
>> What might have happened is that the movdqu instruction faulted (as it's
>> an fpu instruction), and on the way back from the fault, ds and es
>> didn't get restored correctly.
>> 
>> You can test this by writing a trivial version of g_str_equal()
>> somewhere in the qemu source code and rebuilding it.
>> 
>> 
> 
> from entry_32.S:
> 
> .macro RESTORE_REGS pop=0
> 	RESTORE_INT_REGS
> 1:	popl_cfi %ds
> 	/*CFI_RESTORE ds;*/
> 2:	popl_cfi %es
> 	/*CFI_RESTORE es;*/
> 3:	popl_cfi %fs
> 	/*CFI_RESTORE fs;*/
> 	POP_GS \pop
> .pushsection .fixup, "ax"
> 4:	movl $0, (%esp)
> 	jmp 1b
> 5:	movl $0, (%esp)
> 	jmp 2b
> 6:	movl $0, (%esp)
> 	jmp 3b
> .popsection
> 
> this piece of code tries to restore %ds, and if it fails, zeros it,
> which is consistent with the core dump.
> 
> This could happen if kvm is failing to restore GDT correctly.
> 

Possible culprit: b2da15ac26a0c00.


-- 
error compiling committee.c: too many arguments to function