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Date: Tue, 19 Jun 2012 16:52:56 -0500
From: Scott Wood <scottwood@freescale.com>
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Subject: Re: [Qemu-devel] [PATCH] tci: don't write zero for reloc in
	tci_out_label
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To: Stefan Weil <sw@weilnetz.de>
Cc: Blue Swirl <blauwirbel@gmail.com>, qemu-devel@nongnu.org

On 06/19/2012 12:53 AM, Stefan Weil wrote:
> Am 19.06.2012 04:31, schrieb Scott Wood:
>> If tci_out_label is called in the context of tcg_gen_code_search_pc, we
>> could be overwriting an already patched relocation with zero -- and not
>> repatch it because the set_label is past search_pc, causing a QEMU crash
>> when it tries to branch to a zero label.
>>
>> Not writing anything to the relocation area seems to be in line with what
>> other backends do from the couple I looked at (x86, ppc).
> 
> Thanks, this might fix a crash which I have seen from time to time.
> I'll run tests as soon as possible.
> 
> Could you please also look at the other backends?
> 
> I saw from git history that ppc once had the same bug.
> The sparc backend (and maybe others) might still have it.

SPARC looks wrong; the others look OK as far as I can tell from a quick
glance, without being familiar with all of the architectures.

-Scott