Re: Testing 5.17 bugfix material

[Jarkko Sakkinen <jarkko.sakkinen@iki.fi>]

On Mon, Jan 24, 2022 at 05:44:43PM +0000, Accardi, Kristen C wrote:
> On Fri, 2022-01-21 at 11:57 -0800, Dave Hansen wrote:
> > Hi Everyone,
> > 
> > There are a few SGX fixes that have showed up in the last week or so,
> > mostly around RAS and fixing the backing storage issues.  Could folks
> > please give this branch a good thrashing?
> > 
> > > https://git.kernel.org/pub/scm/linux/kernel/git/daveh/devel.git/log/?h=x86/sgx
> > 
> > I'm planning to send this bunch up to Linus after 5.17-rc1 comes out.
> > 
> > Kristen, I really dug into the changelogs of your two patches to make
> > it
> > more clear that they are bugfix and stable@ material.  I'd appreciate
> > some additional eyeballs there.
> 
> There's a bug in the calculation for the available backing bytes,
> pointed out by Haitao and team. Here's a fix applied to your tree.
> 
> From 2ebcf0e70b1235224410e08c983e357d5ac3c435 Mon Sep 17 00:00:00 2001
> From: Kristen Carlson Accardi <kristen@linux.intel.com>
> Date: Mon, 24 Jan 2022 09:28:56 -0800
> Subject: [PATCH] x86/sgx: fixup for available backing pages calculation
> 
> Remove improper parentheses from calculation for available backing
> bytes. Without this fix, the result will be incorrect due to
> rounding.
> 
> Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
> ---
>  arch/x86/kernel/cpu/sgx/main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
> index 7ed6a1b10c21..10a6af89bf64 100644
> --- a/arch/x86/kernel/cpu/sgx/main.c
> +++ b/arch/x86/kernel/cpu/sgx/main.c
> @@ -922,7 +922,7 @@ static bool __init sgx_page_cache_init(void)
>  		return false;
>  	}
>  
> -	available_backing_bytes = total_epc_bytes * (sgx_overcommit_percent / 100);
> +	available_backing_bytes = total_epc_bytes * sgx_overcommit_percent / 100;
>  	atomic_long_set(&sgx_nr_available_backing_pages, available_backing_bytes >> PAGE_SHIFT);
>  
>  	return true;
> -- 
> 2.20.1
> 

So what about sgx_reclaim_pages() having no return value that Haitao
pointed out?

Acked-by: Jarkko Sakkinen <jarkko@kernel.org>

/Jarkko