| Re: [hatari-devel] Disk driver memory access checks |
[ Thread Index |
Date Index
| More lists.tuxfamily.org/hatari-devel Archives
]
- To: hatari-devel@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [hatari-devel] Disk driver memory access checks
- From: Uwe Seimet <Uwe.Seimet@xxxxxxxxx>
- Date: Sun, 14 Oct 2018 10:48:16 +0200
- Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1539506896; s=strato-dkim-0002; d=seimet.de; h=In-Reply-To:References:Message-ID:Subject:To:From:Date: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=hXp072MgCRXhBkanVC+zLg2e2DDVNuhoyXc2zOOu9Ug=; b=TvTd4dszU4ZTwSx/0ZJrBiH9YxPHPfSrxWRBoodoJjnloUVRH/oUvkFcwehNjW3fFK kJxn0ht7kW6lOaaejBqhv5Melq1EYfN+O5KRjUVZLRl5QQFOx8hn8MppfP/sCGvNCjfr xRQlX9yIF9vIsIysn5tCpNdNA+oDc5aTvR5CRlKZKjG4SMwzMBFcu5UOQsrWQ9WgbrAQ E80nfso9tzKwtnTZk3c/4DudZY3pyW1FHX/oNle596CW8wqQZZjnZEtVBouVXnvFtfG1 eDDQ/br6JceAKeV132bAZ7k/hB/bRcbAfgReMojruXLtDX9pJv2/yiAYSPpw8/lX/qKP ozng==
Thank you!
> Hi,
>
> Thanks! Pushed.
>
>
> - Eero
>
> On 10/13/18 11:30 PM, Uwe Seimet wrote:
> > Hi,
> >
> >> The main thing is to protect the emulation process i.e. prevent
> >> Hatari itself doing invalid memory access.
> >>
> >> What else driver does in such a corner case is less of a concern
> >> from my point of view. For now, you could log an error and
> >> later once it's checked on real HW, add proper error response.
> >
> > Thinking more about this, even with real hardware there is no
> > well-defined behavior. Even with SCSI/ACSI DMA you often also need PIO,
> > or data transferred via DMA have to be copied to their final address, e.g.
> > for SCSI transfers to/from ST-RAM and for transfers to/from odd addresses.
> > Only for IDE it's always PIO, at least on original Atari machines. The
> > Milan supports IDE DMAE, but there is no DMA-capable IDE driver for it.
> >
> > The attached patch allows writes from RAM and ROM and reads to RAM only.
> > This should be fine, at least it does not contract any documented behavior.
> >
> > Best regards
> >
> > Uwe
> >
>
>