From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792584942; b=KY9PPGfC4ShlSMfBYpUFwg9GnMVVEkfsmSbD872IJ+p/7lKkvGekERHpjtq4sABi488h wmh6S7X59OMxWADQ7qvOt8Q91inem7caIqF6EmqKTVh2IjE/Xme+AZpQa/VXXYHwbG6/S oxXZRIWgkKYWdSvAltxd1s/+xIyxOp8+VUxBSce3r8m6fumsmZHntgesD4/RlVXi/Yly+ 9ley3nWVgyKjLv24g3MVW8Ca94p1ZBNCMGqUe61FUJW3mHuRKfxHu10WN4SMzWfnZUMeY /m5gi6+/ygNpWMc5bHv/AvXn5TL5h59/jTPyvXDTbnK0tJOXZnQ4mzl91St/nGZo+iA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792584942; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=QUsgGgZf6OKiFgye8YnCV2MQ6FxlmV1JYer/VdbmAtE=; b=r/viQQQW9YGbRa9Jy9xfCMwfNGO79WhH/m2iBJTsIVT9UPOZR2ZgKzcqpOV7gpHjDg2d +SNMRN9bzrJMIJcwsNTajghgkrWFYb0WUYGQeKXL/T4i0Dwk8vLt/eHj+T423RHR5fV+2 EDwgdXRSFuISyuuTi/n3gzmBiDvVxQOnGoDOEDYn9XEJmGoSMW42nStzdexzz29VdfKuq XYWQF0ubzEkYEjkvbvuuPO2yrY8LRJhHxMzFdEAJd1TTaB36OXDb3ABiPOOuVZXfvizC4 fl2fr3O/eqttqMkumDmfgYn+7ylO/TO8+TOFJoCeUFy7heu/5K7nHydJw0kzJKYsCww== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ALkRgYOS; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9825760A382F; Wed, 21 Oct 2026 12:15:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ALkRgYOS Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9EEE1F000C5; Wed, 21 Oct 2026 12:15:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792584942; bh=QUsgGgZf6OKiFgye8YnCV2MQ6FxlmV1JYer/VdbmAtE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ALkRgYOSOKObTXXyQsuGTQgv+LjV+bcSIidAea6KikNC6myOCM668wlHozP1QIcRX 3OGxJG+gE/gp7HQvJwvquMaoEMWQiDwyi4LoQOo9BBVEsfSVEm5l6yVgm0Z+X6KgOU FvLeBwfrzxG1V9wmTHh4o2HXOPn3w6gbivJzTkLGzVTnficzQiMT3P1h+BjyZwSGZ0 bLUc6+AF8E26lCDImnoBVg1/+Xg9G+pKp+1EN15unra3K+FLEFj5QUXQ8PYpSSwsK6 ANKvj5eSSuMR1l0dfL/LKVN98oWzgjaplYJ5Ed65fkYWpM8knZVVjuWcnbd4Bc8td5 1wUkERrtrWDRA== From: Lee Jones To: lee@kernel.org, Qunqin Zhao , Yinggang Gu , Huacai Chen , linux-crypto@vger.kernel.org, mfd@lists.linux.dev, linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Subject: [PATCH 17/28] mfd: loongson-se: Reinitialise completions and wait uninterruptibly for commands Date: Wed, 21 Oct 2026 12:09:39 +0000 Message-ID: <20261021121245.3111563-17-lee@kernel.org> X-Mailer: git-send-email 2.56.0.218.g1ec904b173-goog In-Reply-To: <20261021121245.3111563-1-lee@kernel.org> References: <20261021121245.3111563-1-lee@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit loongson_se_send_controller_cmd() and loongson_se_send_engine_cmd() wait on se->cmd_completion and engine->completion using wait_for_completion_interruptible() without reinitialising the completion before issuing a new command. Because the hardware has no mechanism to abort an in-flight command once accepted by loongson_se_poll(), returning early on a signal leaves the controller or engine actively processing the shared command registers and DMA buffers in the background, and its subsequent completion interrupt leaves a stale completion token that causes the next command to return prematurely. Clear any stale pending interrupt status and reinitialise the target completion inside loongson_se_poll() while holding se->dev_lock immediately before notifying the controller, and wait uninterruptibly via wait_for_completion() once loongson_se_poll() confirms the command has been accepted by the hardware. Fixes: e551fa3159e3 ("mfd: Add support for Loongson Security Engine chip controller") Closes: https://sashiko.dev/#/bug/linux-4661fb0d-d936-4168-89cd-2f6dec31a7b5 Cc: stable@vger.kernel.org Signed-off-by: Lee Jones --- drivers/mfd/loongson-se.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/mfd/loongson-se.c b/drivers/mfd/loongson-se.c index 485ee4a6ca5e..9b531e62fb85 100644 --- a/drivers/mfd/loongson-se.c +++ b/drivers/mfd/loongson-se.c @@ -37,13 +37,17 @@ struct loongson_se_controller_cmd { u32 info[7]; }; -static int loongson_se_poll(struct loongson_se *se, u32 int_bit) +static int loongson_se_poll(struct loongson_se *se, u32 int_bit, + struct completion *completion) { u32 status; int err; spin_lock_irq(&se->dev_lock); + writel(int_bit, se->base + SE_S2LINT_CL); + reinit_completion(completion); + /* Notify the controller that the engine needs to be started */ writel(int_bit, se->base + SE_L2SINT_SET); @@ -66,11 +70,13 @@ static int loongson_se_send_controller_cmd(struct loongson_se *se, for (i = 0; i < SE_SEND_CMD_REG_LEN; i++) writel(send_cmd[i], se->base + SE_SEND_CMD_REG + i * 4); - err = loongson_se_poll(se, SE_INT_CONTROLLER); + err = loongson_se_poll(se, SE_INT_CONTROLLER, &se->cmd_completion); if (err) return err; - return wait_for_completion_interruptible(&se->cmd_completion); + wait_for_completion(&se->cmd_completion); + + return 0; } int loongson_se_send_engine_cmd(struct loongson_se_engine *engine) @@ -80,12 +86,15 @@ int loongson_se_send_engine_cmd(struct loongson_se_engine *engine) * where to obtain engine commands from. Now all we need to * do is notify the controller that the engine needs to be started. */ - int err = loongson_se_poll(engine->se, BIT(engine->id)); + int err = loongson_se_poll(engine->se, BIT(engine->id), + &engine->completion); if (err) return err; - return wait_for_completion_interruptible(&engine->completion); + wait_for_completion(&engine->completion); + + return 0; } EXPORT_SYMBOL_GPL(loongson_se_send_engine_cmd); -- 2.56.0.218.g1ec904b173-goog