From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6292128851F for ; Wed, 8 Jul 2026 15:44:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783525471; cv=none; b=OmdIbESYK2xRw8S4IQ2pkXqrAG5Zlnf/O2PdyKyZ7YcFA8I8GrKB/Ig4cd2MjsdjeOgGGPTcAO3MinWJNGOhILn/JqyjIPC6Y4PJYkutNA3yO2LnVwR13fVQ60ONqq5HtD0fkKAe5GatumfloQQNF2AfZ2VX1NmuS4Omx9CSW8Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783525471; c=relaxed/simple; bh=UKbqtZSVOmyDH06qoHbHTdJbY8TD+eB3KEsU9YQEXAc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uo4ZkX/zjsnEs+XoOVammHxfgQWWbZv3PdHjaK1czMYwGMa9U3LADVUzx8a4L27Fg/U4wAl8RkpZ6GXc1LrG3W4rUoDzJz39tOdambMPS7+dR5w4AVpBM/m2CQA0r95km4Uem6mFUyfSqFRXAVT6Vsz8m5vraiPwkiPKjQr4TmY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=gD2LbyFU; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="gD2LbyFU" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-ID:Content-Description; bh=GSWfbulqSrBo9Aqd7HgrfFBKoFGaoPICpJEsQJ+UIgU=; b=gD2LbyFUU/rJB39UftdTVK1Cja q3sdym9kOxqYAMbmfziKPav4nzPT4JSbMtHvxwQeDx3ytcuTJBwFJwBc97zAzeMlCXiyDisguVtvt wyyHy1z2GcCskAoHo8RDzXAAOtQGKLCIPaOdRkr7eDMZuk8+fUGnMHJ7MvXRLpHfoEu7OEL1wLRy5 lN667xO9g6OfNMUUIz8zasgC9pjdLWLb3eK88bAJv7suItiY5MbVfWXiaLSaTz/OaVAHgDn39nxQ1 xg2Ys7XLRA8p1v3s/W22OY8/VYkESKQVa9/sGygnZW9/agP95YNlCUtukBVeY81mBjinJDsZo1Rs5 vyyWo6tg==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1whURh-0033JE-0q; Wed, 08 Jul 2026 15:44:21 +0000 Date: Wed, 8 Jul 2026 08:44:17 -0700 From: Breno Leitao To: "Liam R. Howlett (Oracle)" Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, maple-tree@lists.infradead.org Subject: Re: [PATCH v2 03/19] maple_tree: Add write lock checking with lockdep sequence numbers Message-ID: References: <20260630190843.3563858-1-liam@infradead.org> <20260630190843.3563858-4-liam@infradead.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260630190843.3563858-4-liam@infradead.org> X-Debian-User: leitao Hello Liam, On Tue, Jun 30, 2026 at 03:08:27PM -0400, Liam R. Howlett (Oracle) wrote: > +#ifdef CONFIG_RCU_STRICT_GRACE_PERIOD > if (!mt_locked(mas->tree)) { > if (mt_in_rcu(mas->tree)) > WARN_ON_ONCE(poll_state_synchronize_rcu(mas->rcu_gp)); Testing next-20260706 on arm64 under a stress-ng + fork/exit/mprotect workload, I'm hitting the new maple_tree write-lock sequence check: WARNING: lib/maple_tree.c:1188 at mas_store_prealloc+0x2a8/0xac0 It fires from several core mm paths — fork (dup_mmap), exit (exit_mmap), and mprotect (__split_vma) — across multiple processes. The two cleanest traces are both in the mprotect path: WARNING: lib/maple_tree.c:1188 at mas_store_prealloc+0x2a8/0xac0, CPU#67 Call trace: mas_store_prealloc+0x2a8/0xac0 (P) vma_iter_store_new+0x2b4/0x3c8 vma_complete+0x258/0x7c0 __split_vma+0x64c/0x770 vma_modify+0x11fc/0x1808 vma_modify_flags+0x18c/0x220 mprotect_fixup+0x22c/0x4e8 do_mprotect_pkey+0x558/0x720 __arm64_sys_mprotect+0x88/0xa8 WARNING: lib/maple_tree.c:1188 at mas_prev+0x160/0x1a8, CPU#67 Call trace: mas_prev+0x160/0x1a8 (P) __split_vma+0x658/0x770 vma_modify+0x11fc/0x1808 vma_modify_flags+0x18c/0x220 mprotect_fixup+0x22c/0x4e8 do_mprotect_pkey+0x558/0x720 __arm64_sys_mprotect+0x88/0xa8 Is this a known issue?