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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Shuah Khan , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Jann Horn , linux-kselftest@vger.kernel.org, kernel-team@android.com, Lokesh Gidra , bpf@vger.kernel.org, netdev@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, Peter Xu Subject: Re: [PATCH v3] selftests/mm: Fix ARM related issue with fork after pthread_create Message-Id: <20240325130426.fba5287fcc437475123e76cc@linux-foundation.org> In-Reply-To: <20240325194100.775052-1-edliaw@google.com> References: <20240325194100.775052-1-edliaw@google.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 1452D14000D X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 15jp4yyxqm3r8c1konp6y6bmx33sf3mb X-HE-Tag: 1711397071-795565 X-HE-Meta: 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 MS0gCNdW K79woj2Rv2VakQb9cr4XjhV+2GZyTYz8LyUpYVDcinWbtVsz3BPVJ5MPKfM/5KHobG9sBzNLcCCpJ1ydoWlRK/5ntawwP9tiMhviU8n/l8jUkeY2vBpcFu0x6U/eA+OoqdLtO0x1ppVdiYSjct9LEOSPbGIjTpeIy7WxsqM8Ime3MJgzQVzeBqsvXlnpllw9hUO0e9O3iLhIXcJXZ7WLSn3N0Et6NIrejCEB6M6/66qmMuBQqHgqvR/qMSwSTyAxmzi0jTL/jf5+rkHRJVZcJKYC6WAn9RUs2wgOB++qal8Fr3g6IlJ4/U3uLCbgXIM2hxf3DichSBdUx0UYQZGKEUXgUQ/+gvvAswJMAM1dyqYSznIHC55jWfaLh5A== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, 25 Mar 2024 19:40:52 +0000 Edward Liaw wrote: > Following issue was observed while running the uffd-unit-tests selftest > on ARM devices. On x86_64 no issues were detected: > > pthread_create followed by fork caused deadlock in certain cases > wherein fork required some work to be completed by the created thread. > Used synchronization to ensure that created thread's start function has > started before invoking fork. hm, you cc'ed the whole world apart from peterx. Fixed. > Signed-off-by: Lokesh Gidra > [edliaw: Refactored to use atomic_bool] > Signed-off-by: Edward Liaw I'll add cc:stable. For which a Fixes: is desirable. I used 760aee0b71e3 ("selftests/mm: add tests for RO pinning vs fork()"), please check that.