From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A43661C68AE; Tue, 27 Aug 2024 14:48:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724770110; cv=none; b=TuJmO8hXJlm/A92yYmK2tFO6x4TmeOudlMgZV4aXJiaY5Grd3sErrBFS1CeNsnInrEBL+rztg8ZJdVSnuWZ+a24lJnbFJXi9ZF1lnEppICdiqolnLwS4MqLNB8gIhAuT8WW0lju6guux+zYqz4Hq3cqHySKluKoU+fri3XK5abI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724770110; c=relaxed/simple; bh=SMT3xHBrSIRblYImAMh12G/OzNy6T39+exZcJ7Kc59g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=koiCRKWtVyLASdW/VkzJOwiDIAZyRayPjkI6kY+71/tvr9M4pfocdu1P9l/NyEUwq71zSrlAhX3NywUkULxbR8jC1jCJH8xRw82dgjUOyLgSD62D3cOAYr47Nm2HBKlPMVvzAtl88HauOfDJMr7VBPqRkncRAFllFT+V35sb8j4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qL/kUERa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="qL/kUERa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13C9AC4AF14; Tue, 27 Aug 2024 14:48:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1724770110; bh=SMT3xHBrSIRblYImAMh12G/OzNy6T39+exZcJ7Kc59g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qL/kUERan9zFVb3QrWH6YbUGnylKMT12p+YQToRB9WO9uRDRjro2xYmnmG5umZhL4 0rqHdklwUJEH5AIbghOcZcCSzH3Ghh+jUz31Y1YI63Q1DqSDffzbbMB7jNwmyeDlkp MaWx7kpqPaciO2HjbeiL9c4TwHIFNhZfj+UXrnL0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chengfeng Ye , Dennis Dalessandro , Leon Romanovsky , Sasha Levin Subject: [PATCH 6.6 131/341] IB/hfi1: Fix potential deadlock on &irq_src_lock and &dd->uctxt_lock Date: Tue, 27 Aug 2024 16:36:02 +0200 Message-ID: <20240827143848.402150006@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240827143843.399359062@linuxfoundation.org> References: <20240827143843.399359062@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chengfeng Ye [ Upstream commit 2f19c4b8395ccb6eb25ccafee883c8cfbe3fc193 ] handle_receive_interrupt_napi_sp() running inside interrupt handler could introduce inverse lock ordering between &dd->irq_src_lock and &dd->uctxt_lock, if read_mod_write() is preempted by the isr. [CPU0] | [CPU1] hfi1_ipoib_dev_open() | --> hfi1_netdev_enable_queues() | --> enable_queues(rx) | --> hfi1_rcvctrl() | --> set_intr_bits() | --> read_mod_write() | --> spin_lock(&dd->irq_src_lock) | | hfi1_poll() | --> poll_next() | --> spin_lock_irq(&dd->uctxt_lock) | | --> hfi1_rcvctrl() | --> set_intr_bits() | --> read_mod_write() | --> spin_lock(&dd->irq_src_lock) | --> handle_receive_interrupt_napi_sp() | --> set_all_fastpath() | --> hfi1_rcd_get_by_index() | --> spin_lock_irqsave(&dd->uctxt_lock) | This flaw was found by an experimental static analysis tool I am developing for irq-related deadlock. To prevent the potential deadlock, the patch use spin_lock_irqsave() on &dd->irq_src_lock inside read_mod_write() to prevent the possible deadlock scenario. Signed-off-by: Chengfeng Ye Link: https://lore.kernel.org/r/20230926101116.2797-1-dg573847474@gmail.com Acked-by: Dennis Dalessandro Signed-off-by: Leon Romanovsky Signed-off-by: Sasha Levin --- drivers/infiniband/hw/hfi1/chip.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c index 0814291a04120..9b542f7c6c115 100644 --- a/drivers/infiniband/hw/hfi1/chip.c +++ b/drivers/infiniband/hw/hfi1/chip.c @@ -13185,15 +13185,16 @@ static void read_mod_write(struct hfi1_devdata *dd, u16 src, u64 bits, { u64 reg; u16 idx = src / BITS_PER_REGISTER; + unsigned long flags; - spin_lock(&dd->irq_src_lock); + spin_lock_irqsave(&dd->irq_src_lock, flags); reg = read_csr(dd, CCE_INT_MASK + (8 * idx)); if (set) reg |= bits; else reg &= ~bits; write_csr(dd, CCE_INT_MASK + (8 * idx), reg); - spin_unlock(&dd->irq_src_lock); + spin_unlock_irqrestore(&dd->irq_src_lock, flags); } /** -- 2.43.0