Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Mon, 30 Apr 2018 09:28:23 -0700
From:   Ram Pai <linuxram@us.ibm.com>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Ingo Molnar <mingo@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        tglx@linutronix.de, mpe@ellerman.id.au, akpm@linux-foundation.org,
        shuah@kernel.org, shakeelb@google.com
Subject: Re: [PATCH 0/9] [v3] x86, pkeys: two protection keys bug fixes
Reply-To: Ram Pai <linuxram@us.ibm.com>
References: <20180427174527.0031016C@viggo.jf.intel.com>
 <20180428070553.yjlt22sb6ntcaqnc@gmail.com>
 <a176ae33-eb01-d275-f372-a33829e865a7@intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <a176ae33-eb01-d275-f372-a33829e865a7@intel.com>
User-Agent: Mutt/1.5.20 (2009-12-10)
Message-Id: <20180430162823.GB5666@ram.oc3035372033.ibm.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Apr 30, 2018 at 08:30:43AM -0700, Dave Hansen wrote:
> On 04/28/2018 12:05 AM, Ingo Molnar wrote:
> > In the above kernel that was missing the PROT_EXEC fix I was repeatedly running 
> > the 64-bit and 32-bit testcases as non-root and as root as well, until I got a 
> > hang in the middle of a 32-bit test running as root:
> > 
> >   test  7 PASSED (iteration 19)
> >   test  8 PASSED (iteration 19)
> >   test  9 PASSED (iteration 19)
> > 
> >   < test just hangs here >
> 
> For the hang, there is a known issue with the use of printf() in the
> signal handler and a resulting deadlock.  I *thought* there was a patch
> merged to fix this from Ram Pai or one of the other IBM folks.

Yes. there is a patch. unfortunately that patch assumes the selftest has
been moved into selftests/vm directory.  One option is --  I merge your
changes in my selftest patchset, and send the entire series for upstream
merge.

Or you can manually massage-in the specific fix.
The patch is "selftests/vm: Fix deadlock in protection_keys.c"
https://patchwork.ozlabs.org/patch/864394/

Let me know,
-- 
Ram Pai