Re: [fix] Too async libata breakage

["Justin P. Mattock" <justinmattock@gmail.com>]

Arjan van de Ven wrote:
>>> Additional async_synchronize_full() helps and box boot to the end.
>>>       
>
> Hi Linus,
>
> can you add the patch below to your tree? This makes the
> async_synchronize_full() a real absolute async barrier, rather than
> just synchronizing the work scheduled upto the starting point.
> It's a bit too much for some cases (so later on I might introduce the
> softer synchronization again) but it solves some real problems
> for people so this should go into -rc1 please...
>
> >From ca1827b142e41b54c612026b3c0b5d239f21a715 Mon Sep 17 00:00:00 2001
> From: Arjan van de Ven <arjan@linux.intel.com>
> Date: Thu, 8 Jan 2009 12:35:11 -0800
> Subject: [PATCH] async: make async_synchronize_full() more serializing
>
> turns out that there are real problems with allowing async
> tasks that are scheduled from async tasks to run after
> the async_synchronize_full() returns.
>
> This patch makes the _full more strict and a complete
> synchronization. Later I might need to add back a lighter
> form of synchronization for other uses.. but not right now.
>
> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
> ---
>  kernel/async.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/kernel/async.c b/kernel/async.c
> index 9737338..64cc916 100644
> --- a/kernel/async.c
> +++ b/kernel/async.c
> @@ -206,7 +206,9 @@ EXPORT_SYMBOL_GPL(async_schedule_special);
>  
>  void async_synchronize_full(void)
>  {
> -	async_synchronize_cookie(next_cookie);
> +	do {
> +		async_synchronize_cookie(next_cookie);
> +	} while (!list_empty(&async_running) || !list_empty(&async_pending));
>  }
>  EXPORT_SYMBOL_GPL(async_synchronize_full);
>  
>   
I'm getting this as well,
happens three to two times in a row,
then I'll get a good bootup.
going to try and see if I can grab a log
with ohci1394

regards;

Justin P. Mattock