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Date:   Thu, 1 Dec 2022 16:48:20 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Bernd Edlinger <bernd.edlinger@hotmail.de>, ebiederm@xmission.com
Cc:     limin <limin100@huawei.com>, shuah@kernel.org,
        ebiederm@xmission.com, linux-kselftest@vger.kernel.org,
        linux-kernel@vger.kernel.org, songmuchun@bytedance.com,
        lizefan.x@bytedance.com
Subject: Re: [PATCH -next] selftests/ptrace: Fix Test terminated by timeout
 in ptrace_attach
Message-ID: <202212011638.31BBB562B@keescook>
References: <20221128070454.1850273-1-limin100@huawei.com>
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On Mon, Nov 28, 2022 at 08:56:09AM +0100, Bernd Edlinger wrote:
> thanks for cleaning this up.

Oh, hm, I never saw the original email -- I'll check my Spam folder, it
gets overly excited sometimes.

> Just for completenes:
> 
> I have actually two patches submitted a while ago, but did not get any response so far,
> one that would make the test case work as it is:
> 
> [PATCH v10] exec: Fix dead-lock in de_thread with ptrace_attach
> https://lore.kernel.org/lkml/AM8PR10MB470801D01A0CF24BC32C25E7E40E9@AM8PR10MB4708.EURPRD10.PROD.OUTLOOK.COM/
> 
> and my favorite one, that would fix the dead-lock altogether (and adjust the test case accordingly):
> 
> [PATCH v11] exec: Fix dead-lock in de_thread with ptrace_attach
> https://lore.kernel.org/lkml/AM8PR10MB470875B22B4C08BEAEC3F77FE4169@AM8PR10MB4708.EURPRD10.PROD.OUTLOOK.COM/

This fell off my radar, but let's look at it again. Is this still an
existing race after Eric's various refactorings? I assume so. Eric, can
you looked at this case?

-- 
Kees Cook