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Date: Mon, 27 Oct 2014 14:30:36 -0400
From: John Snow <jsnow@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 5/6] ide: Correct handling of
	malformed/short PRDTs
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To: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org
Cc: kwolf@redhat.com, armbru@redhat.com, stefanha@redhat.com, mst@redhat.com



On 10/27/2014 06:06 AM, Paolo Bonzini wrote:
>
>
> On 10/02/2014 12:55 AM, John Snow wrote:
>> +    /* If this is true, you're leaking memory. */
>
> ... or qsg is uninitialized, which would work because qemu_sglist_init
> initializes all fields.
>
> This is the only comment I have on the series. :)
>
> Paolo
>
>> +    assert(qsg->sg == NULL);
>> +
>>       qsg->sg = g_malloc(alloc_hint * sizeof(ScatterGatherEntry));
>
>>
>> @@ -1147,7 +1147,7 @@ static int ahci_dma_prepare_buf(IDEDMA *dma, int is_write)
>>       s->io_buffer_size = s->sg.size;
>>
>>       DPRINTF(ad->port_no, "len=%#x\n", s->io_buffer_size);
>> -    return s->io_buffer_size != 0;
>> +    return s->io_buffer_size / 512 != 0;
>>   }

oh, yeah :\

I really did want to guard against re-initialization, but if it's 
expected that this structure may have completely anything in it at init 
time, I don't really have a way to do that, do I.

I guess I'll just delete the assertion, unless you have a very simple 
idea to help guard against double-inits.

--j