From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f176.google.com (mail-pl1-f176.google.com [209.85.214.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 67743175A9D for ; Tue, 23 Jun 2026 14:32:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782225149; cv=none; b=pamLHZ0szq9FQs5GdPqRhFk/Tbrr451hF62IZM0FUQorhzMU8LS6kbKU3umtUWcS8Zn/+A1113kjfIblyPz2/MYkQp75f9SPQqyup+7KGu9zdT7UtKbnjC20PRynkWjHmO39CosI2U7FZ5Ybe8lvTxdhUnwTWQp32b/uxedimxo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782225149; c=relaxed/simple; bh=3mG39iHCZNsXxuzctgS4ljx3FJbNgfE7+EfdkoW77lE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YY6OVllhDrMQG3yD231mb/bWxcYtTv2ITx01Dl1c2ewn1pqGFJ5gqD1MAitcyvqzqP0y6e6JRQ7noY28PxCYNk6ciKXzcPBI4kxenxGY3mT5Ks1cLMZSWGVevRMK710i5MjN092UyyXUXsuZytNQtha12zP88xxM/Vs6kOjYo2E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=GV4a1JDP; arc=none smtp.client-ip=209.85.214.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="GV4a1JDP" Received: by mail-pl1-f176.google.com with SMTP id d9443c01a7336-2c6b3f71648so62687045ad.2 for ; Tue, 23 Jun 2026 07:32:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782225148; x=1782829948; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=wcdDEOHP11KOemg3W2Imt3ngTY3JQturNvk8u+a077k=; b=GV4a1JDPloALdbNmfqbyXdbISVi1RYNJxzBL2a/hzXEWWxxIC2DtFTB9qZempgODSJ KS331OA4mjKrfuy6L4tnash8CuCHB1+xIgWoQmieGwHzwC8+Q3nON9Hm/xDIqinR/tQ3 HsVIqut2tB3V/pjn6zwOKj+wrM4pnVwsXIVCOp6qWVJApF7rMoxqIkXR6W05fNDRuA0M Jg/B6WTH6+XcjWtxzIg/DMyqh1bCrQgddMgmFxQVGlLhsxGgoKIZ2ZFcwS19MUfbgLLk NlM5IcU3zOD0AuGDE14gtp7d4/PC8Xvrs2Ek6UfI5LAVkc4s4LK4JfWoq8P7z3pD8FE8 FA4g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782225148; x=1782829948; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=wcdDEOHP11KOemg3W2Imt3ngTY3JQturNvk8u+a077k=; b=mGHixq8GWX4Q8lM2SeXWSoLS/pvajxVWRhWuHXwSu38QUgBon8NNwNJwhPQul48wKF PvJ416l04x4G/1G3L91uAZXxg/5Yp57UXS2DZeNIWFTCyzy3AyfJbUJjf/5kkms8+IRW 7gafbRQlntWVHl80vjAKNVyFBlEY9hNPCLOR8h+4mcXXngpyltUt/v12csBO+j3V34bg t6riGtAXWWESa/TqICfMjtYcjkWgdM+WnctufZAphrnyZuV3Nipe5r0n9XvTcryjUgz8 A3fwd0jPNdIP2P75/hyr3ArHB8uqfrI+LuBkvGK1hDTiS4oqXxpGoIlTS7Mm9PRnD8OZ c/7A== X-Forwarded-Encrypted: i=1; AHgh+RrAe/M1ax3QzFhXqUxKuOCxk6dbQHwwyKz94aVB9RJwfGMN1NK8MI/9DFaPRYWqrdsnx8m0DJFhZcu6TPs=@vger.kernel.org X-Gm-Message-State: AOJu0Yz3jxwbeek+V+4xjEM5aRpw2XOAFgasT36cHHRGo1Z4bHo6TZam nYMWkKTe35wP4eiSfHIQF1nNc0aKKWbLy2ZHUH9ipLX7y1bWBrMmfvOt X-Gm-Gg: AfdE7clBnqRz8NATtLOHgg64SWUEgfKZ67DHhlnyzjNWN1OnW5LkWHTUXZ2AMmW3sjs 4qscG8o4ccUn4OrspEDeMJ7PFq9U+OLm8mBj7SbtI3qbHZXmG4W+8zbgWdhC0zhm5bX6yOHVZUg c4P+6YwcStWZ646Q+HdGUYTfqA5GmSFfE864ZAmpkcuH6S/MV+wLfcdpH/8BcapaXHY46M59kP9 q9k9T3xVhy2SI8gmEKHcw4mhiL1aEo1M0GAlcEfKCwP2SBk3YQahT2nlxOcaw9ZMNhgYliOK8YA I6iGKLU+nXTuNUu1572iYXSymk4PmrjTaqS46+9rZOb5rtaZdIGhUYnWvSg8cbcO4zQpZAP9EJ2 nwzIY0DHgbsZ2RNGxG4ePpoWIwGo8/3J+D3kU0pOd0y2Za1iKqRybQjM+FMbNZ+q01eufhDt2TL xdRhyoAq7TSkKpD2pKZw== X-Received: by 2002:a17:903:2f87:b0:2c0:c262:b91f with SMTP id d9443c01a7336-2c718cb08b0mr212161755ad.8.1782225147522; Tue, 23 Jun 2026 07:32:27 -0700 (PDT) Received: from ubuntu.. ([138.199.21.246]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2c743bfe8aasm104014885ad.68.2026.06.23.07.32.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jun 2026 07:32:26 -0700 (PDT) From: Jing Wu To: gregkh@linuxfoundation.org Cc: jirislaby@kernel.org, avorontsov@ru.mvista.com, alan@redhat.com, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, wangzhaolong@fnnas.com Subject: Re: [PATCH v4] serial: 8250: fix use-after-free in IRQ chain handling Date: Tue, 23 Jun 2026 22:32:20 +0800 Message-ID: <20260623143220.432877-1-realwujing@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <2026061213-blinker-portable-a198@gregkh> References: <20260529-bug-221579-8250-shared-irq-race-v4-1-cfda63b4420f@gmail.com> <2026061213-blinker-portable-a198@gregkh> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Qiliang Yuan On Fri, Jun 12, 2026 at 11:49:51AM +0200, Greg Kroah-Hartman wrote: > What real systems causes this to happen? How are you triggering this > warning to happen? How was this tested? The original report is Bugzilla #221579 from Wang Zhaolong. The bug triggers on systems with multiple 8250 serial ports sharing an IRQ (e.g. NAS-like devices). It can be reproduced by probing/removing 8250 serial ports that share an IRQ. Wang confirmed off-list that v3 fixes the reproducer on his setup. > Shouldn't the function be marked as requiring this lock to be held? > Just putting in this lockdep_assert will not catch the static analysis > tools :( Agreed, will add __must_hold(&hash_mutex) in v5. Thanks, Qiliang