From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f44.google.com (mail-wm1-f44.google.com [209.85.128.44]) (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 816EBF9E2 for ; Mon, 15 Jan 2024 08:50:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="Z3QVAqah" Received: by mail-wm1-f44.google.com with SMTP id 5b1f17b1804b1-40e69b3149fso26489455e9.3 for ; Mon, 15 Jan 2024 00:50:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1705308657; x=1705913457; darn=vger.kernel.org; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=2910EaSJimoxj7S9UbVP581OYEFXh/5jg4WfdJzrEAM=; b=Z3QVAqahulMokf5w2z1so3pibsXYsDo4PUK49nrXz9ohevq2tMEI8OVzg1P3Il8HSQ 8BWHcAhITQnsf4djFeTIVbNi/WjlwmTh/8Mlvj+KUWg1gr45d4s7UvywHUWhL1X0bNVF NCeY2ltF2br49YHWDPypd8ACap0OUUl5jsK7Z5RetE79DfHUAczyyvK4o4sSgsOiQcIl EsLfrXd2hDvPqHjW+QofYEULc3sA8iuvTJp4UOP6IbvOnYDVxNgTGFpCZ02w/UvvGqBl LSeBEJeAGvEscCVj2rxaGD1tRoMF58ILKvP2qkBZYPFnz7+p3ji5T1/wib/doi33slMM eKlQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705308657; x=1705913457; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=2910EaSJimoxj7S9UbVP581OYEFXh/5jg4WfdJzrEAM=; b=k+xON0u3HtqZzjwcLiS+9hGb9HqJJVwQh0r8CHjksealJzYK/6X/LeRjCHAfPjwRuj 5Y/DEcC9YRyPsLW5oIx13PXERksAbkKGbla5THmXnN8CghRMY83gMhWCK26ONxkMPHa+ WdD2mkmH0EQCpjt8NCSnzVuRhmpKSq5gN+zJhFL2doP0ocsAnU743DuIFNzyFT4QI9vQ DNNCveVJ8wVfE7K/cYmdTv2qZQ9ulIXDIFY3U22Q43I1dG8eHwo1OyxW5iC5XFxN2nX3 rdAr4e+zAVeEwBTbHFenCQJllps4UVkhxKSnRhWkqlpZSzc99Bf4K2TY+wv7iQwMeI/H EHXA== X-Gm-Message-State: AOJu0YyM+mKkwjLpMPt5bM2eHc3843fB1K5ZjMh+zfwaFoZLoHF+xr4R u9KqKYbU132fmoU5N5hbFf//6pZskOxsNQ== X-Google-Smtp-Source: AGHT+IHMUgFzEwrbsH/HJYEzpeov6g2IZYbrbOHGNw3QDftCCRh8iuDQuKAS+QoP2LSbXn/T7pQ5gg== X-Received: by 2002:a05:600c:35d1:b0:40e:55b0:64df with SMTP id r17-20020a05600c35d100b0040e55b064dfmr2801729wmq.101.1705308656641; Mon, 15 Jan 2024 00:50:56 -0800 (PST) Received: from localhost ([102.140.209.237]) by smtp.gmail.com with ESMTPSA id f18-20020a05600c155200b0040d87100733sm15182436wmg.39.2024.01.15.00.50.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Jan 2024 00:50:56 -0800 (PST) Date: Mon, 15 Jan 2024 11:50:52 +0300 From: Dan Carpenter To: bartosz.golaszewski@linaro.org Cc: linux-wireless@vger.kernel.org, linux-input@vger.kernel.org Subject: [bug report] gpiolib: use a mutex to protect the list of GPIO devices Message-ID: Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hello Bartosz Golaszewski, The patch 65a828bab158: "gpiolib: use a mutex to protect the list of GPIO devices" from Dec 15, 2023 (linux-next), leads to the following Smatch static checker warning: drivers/net/wireless/ath/ath9k/hw.c:2836 ath9k_hw_gpio_get() warn: sleeping in atomic context drivers/net/wireless/ath/ath9k/hw.c 2826 val = MS_REG_READ(AR9285, gpio); 2827 else if (AR_SREV_9280(ah)) 2828 val = MS_REG_READ(AR928X, gpio); 2829 else if (AR_DEVID_7010(ah)) 2830 val = REG_READ(ah, AR7010_GPIO_IN) & BIT(gpio); 2831 else if (AR_SREV_9300_20_OR_LATER(ah)) 2832 val = REG_READ(ah, AR_GPIO_IN(ah)) & BIT(gpio); 2833 else 2834 val = MS_REG_READ(AR, gpio); 2835 } else if (BIT(gpio) & ah->caps.gpio_requested) { --> 2836 val = gpio_get_value(gpio) & BIT(gpio); ^^^^^^^^^^^^^^ 2837 } else { 2838 WARN_ON(1); 2839 } 2840 2841 return !!val; 2842 } Before gpio_get_value() took a spinlock but now it takes a mutex (actually a rw semaphor now). The call tree where we are in atomic context is: ath_btcoex_period_timer() <- disables preempt -> ath_detect_bt_priority() -> ath9k_hw_gpio_get() Another warning this change causes is: drivers/input/keyboard/matrix_keypad.c:95 enable_row_irqs() warn: sleeping in atomic context matrix_keypad_scan() <- disables preempt -> enable_row_irqs() drivers/input/keyboard/matrix_keypad.c:108 disable_row_irqs() warn: sleeping in atomic context matrix_keypad_interrupt() <- disables preempt -> disable_row_irqs() regards, dan carpenter