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Date: Fri, 11 Sep 2015 11:11:41 +0800
From: Fam Zheng <famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 1/1] atapi: abort transfers with 0 byte
 limits
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To: John Snow <jsnow@redhat.com>
Cc: kwolf@redhat.com, armbru@redhat.com, qemu-block@nongnu.org, qemu-devel@nongnu.org

On Thu, 09/10 19:20, John Snow wrote:
>  
> +    /* Nondata commands permit the byte_count_limit to be 0.
> +     * If this is a data-transferring PIO command and BCL is 0,
> +     * we abort at the /ATA/ level, not the ATAPI level.
> +     * See ATA8 ACS3 section 7.17.6.49 and 7.21.5 */
> +    if (!(atapi_cmd_table[s->io_buffer[0]].flags & NONDATA)) {
> +        /* TODO: Check IDENTIFY data word 125 for default BCL (currently 0) */
> +        uint16_t byte_count_limit = s->lcyl | (s->hcyl << 8);
> +        if !(byte_count_limit || s->atapi_dma) {

!( ?

Fam