Re: [Qemu-devel] [PATCH 09/26] ide: Set BSY bit during FLUSH

[Alex Williamson]

On Wed, 2013-06-12 at 16:41 -0500, Michael Roth wrote:
> From: Andreas Färber <address@hidden>
> 
> The implementation of the ATA FLUSH command invokes a flush at the block
> layer, which may on raw files on POSIX entail a synchronous fdatasync().
> This may in some cases take so long that the SLES 11 SP1 guest driver
> reports I/O errors and filesystems get corrupted or remounted read-only.
> 
> Avoid this by setting BUSY_STAT, so that the guest is made aware we are
> in the middle of an operation and no ATA commands are attempted to be
> processed concurrently.
> 
> Addresses BNC#637297.
> 
> Suggested-by: Gonglei (Arei) <address@hidden>
> Signed-off-by: Andreas Färber <address@hidden>
> Signed-off-by: Kevin Wolf <address@hidden>
> Signed-off-by: Stefan Hajnoczi <address@hidden>
> (cherry picked from commit f68ec8379e88502b4841a110c070e9b118d3151c)
> 
> Signed-off-by: Michael Roth <address@hidden>
> ---
>  hw/ide/core.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/ide/core.c b/hw/ide/core.c
> index c7a8041..9926d92 100644
> --- a/hw/ide/core.c
> +++ b/hw/ide/core.c
> @@ -814,6 +814,7 @@ void ide_flush_cache(IDEState *s)
>          return;
>      }
>  
> +    s->status |= BUSY_STAT;
>      bdrv_acct_start(s->bs, &s->acct, 0, BDRV_ACCT_FLUSH);
>      bdrv_aio_flush(s->bs, ide_flush_cb, s);
>  }

This caused a regression for me from 1.5.0->1.5.1.  Windows 7 x64 no
longer boots on q35 IDE with this change.  Thanks,

Alex