Re: [Qemu-devel] [PATCH] ide: remove hardcoded 2GiB transactional limit

[Stefan Hajnoczi]

On Mon, Oct 26, 2015 at 07:38:02PM -0400, John Snow wrote:
> Not that you can request a >2GiB transaction, but that's why checking
> for it makes no sense anymore.
> 
> With the newer 'limit' parameter to prepare_buf, we no longer need a
> static limit. The maximum limit is still 2GiB, but the limit parameter
> is set to the current transaction size, which cannot surpass 32MiB
> (512 * 65536). If the PRDT surpasses the transactional size, then,
> we'll just carry out the normative underflow handling pathways instead
> of needing an extra, strange pathway that worries about hitting some
> logistical cap for the largest sglist we can support -- we'll never
> even attempt to build one that big anymore.
> 
> Reported-by: Kevin Wolf <address@hidden>
> Signed-off-by: John Snow <address@hidden>
> ---
>  hw/ide/ahci.c     | 30 ++++++++++++++----------------
>  hw/ide/internal.h |  2 +-
>  hw/ide/pci.c      |  7 -------
>  3 files changed, 15 insertions(+), 24 deletions(-)

Acked-by: Stefan Hajnoczi <address@hidden>