Re: Testing 5.17 bugfix material

["Accardi, Kristen C" <kristen.c.accardi@intel.com>]

On Mon, 2022-01-24 at 19:56 +0200, Jarkko Sakkinen wrote:
> 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?

I'm taking a look at that, and testing, and will send a separate fix.