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 0FFE712D1F1; Tue, 30 Apr 2024 11:14:52 +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=1714475692; cv=none; b=sQ7Ma3sbOEG1G7FxjUwfP0nUA2WhT/J7vEEBjwdjCn4Ny3wu3XpzcPNy+hxnwk9FM7ZGtk46bS2NJg1vw0eTuClvBocYUKAP7oWHRWtbSNvBvrGMsJZTQ+MRf/zkpNt2ko/IlRunyhYsXEgXgfEK2/FdwbKLFjeqz71Vqz1t2II= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714475692; c=relaxed/simple; bh=BdTnfoBHYFgKskadaMz6MLOHDhH/Mx9y3N7AZXhWWvA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MRX2tnPVDvjzYjfP4q2//ivyPAx7ikIfl+2BdNW1WINDXemQCHEcZ6/Z+AESF+OZeR5FLfcgGpu/djcvCedQ8q81MxuNa2GY4f9ccp+v68TFgJonnvwEr/aw3ZLxXc79TFyDqTbmQ/p1vQrWI/iXZE5pMHHkcmo55V1fZrTRKLg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xDn97EMO; 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="xDn97EMO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A5F6C2BBFC; Tue, 30 Apr 2024 11:14:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1714475691; bh=BdTnfoBHYFgKskadaMz6MLOHDhH/Mx9y3N7AZXhWWvA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xDn97EMOu+Tpc7evygWVKHdbDGaiP99qw0hmfFKYGppbM0i71rea5t12/GjyZIccc xI5kNS4BXgxV0fx7aXmutkXq55Rk0zg0eC6ijz2n1isJRcK5MEFNlEON+hR9GWULBz iaWifSgkgadfupfagmiStgVC+5iSlqwD3N+s6+2M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hans de Goede , Vinod Koul , Sasha Levin Subject: [PATCH 6.6 175/186] phy: ti: tusb1210: Resolve charger-det crash if charger psy is unregistered Date: Tue, 30 Apr 2024 12:40:27 +0200 Message-ID: <20240430103103.111764084@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240430103058.010791820@linuxfoundation.org> References: <20240430103058.010791820@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev 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: Hans de Goede [ Upstream commit bf6e4ee5c43690e4c5a8a057bbcd4ff986bed052 ] The power_supply frame-work is not really designed for there to be long living in kernel references to power_supply devices. Specifically unregistering a power_supply while some other code has a reference to it triggers a WARN in power_supply_unregister(): WARN_ON(atomic_dec_return(&psy->use_cnt)); Folllowed by the power_supply still getting removed and the backing data freed anyway, leaving the tusb1210 charger-detect code with a dangling reference, resulting in a crash the next time tusb1210_get_online() is called. Fix this by only holding the reference in tusb1210_get_online() freeing it at the end of the function. Note this still leaves a theoretical race window, but it avoids the issue when manually rmmod-ing the charger chip driver during development. Fixes: 48969a5623ed ("phy: ti: tusb1210: Add charger detection") Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20240406140821.18624-1-hdegoede@redhat.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/phy/ti/phy-tusb1210.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/phy/ti/phy-tusb1210.c b/drivers/phy/ti/phy-tusb1210.c index b4881cb344759..c23eecc7d1800 100644 --- a/drivers/phy/ti/phy-tusb1210.c +++ b/drivers/phy/ti/phy-tusb1210.c @@ -65,7 +65,6 @@ struct tusb1210 { struct delayed_work chg_det_work; struct notifier_block psy_nb; struct power_supply *psy; - struct power_supply *charger; #endif }; @@ -231,19 +230,24 @@ static const char * const tusb1210_chargers[] = { static bool tusb1210_get_online(struct tusb1210 *tusb) { + struct power_supply *charger = NULL; union power_supply_propval val; - int i; + bool online = false; + int i, ret; - for (i = 0; i < ARRAY_SIZE(tusb1210_chargers) && !tusb->charger; i++) - tusb->charger = power_supply_get_by_name(tusb1210_chargers[i]); + for (i = 0; i < ARRAY_SIZE(tusb1210_chargers) && !charger; i++) + charger = power_supply_get_by_name(tusb1210_chargers[i]); - if (!tusb->charger) + if (!charger) return false; - if (power_supply_get_property(tusb->charger, POWER_SUPPLY_PROP_ONLINE, &val)) - return false; + ret = power_supply_get_property(charger, POWER_SUPPLY_PROP_ONLINE, &val); + if (ret == 0) + online = val.intval; + + power_supply_put(charger); - return val.intval; + return online; } static void tusb1210_chg_det_work(struct work_struct *work) @@ -467,9 +471,6 @@ static void tusb1210_remove_charger_detect(struct tusb1210 *tusb) cancel_delayed_work_sync(&tusb->chg_det_work); power_supply_unregister(tusb->psy); } - - if (tusb->charger) - power_supply_put(tusb->charger); } #else static void tusb1210_probe_charger_detect(struct tusb1210 *tusb) { } -- 2.43.0