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 07E6122ACF2; Thu, 3 Apr 2025 19:18:45 +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=1743707926; cv=none; b=C2Itbhr0I5+Hh86D5GVP5P9unHwmhlCT6SQWKTzV/b2sXzAi89rS50fKazMpKXaLjlQd3Tr5YBCU2dBhDn5/XOPTPidAwx8tV1zmbPhkk0oLY+F+C+4tAbAhYH8efQSUCsyQ1aZ0qDa9vvhuOjdiwaCzMKeYAWrewj9QFpeZJLw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743707926; c=relaxed/simple; bh=M5lvlBDnklOV6b79U716TEv+nYlJaQwiJHtLbD2K4mo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=NsQGJeT1+Sx8f/HNeiagHtxGirGPxN72K5uFTmhXvv2J3GoAnM9olAvhP9ydToeD4RDe9VW+jpMYQpgHpyyWvLEQDNiNDbfwwuCSzUY5d0lgoZnai6oS7+1DZgky1Q6FXVShtJBo+9unkpGaMJ1UF4KzG9DIW+aW4E7IpljUBQA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=B0ugh2/Y; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="B0ugh2/Y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95819C4AF0F; Thu, 3 Apr 2025 19:18:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743707925; bh=M5lvlBDnklOV6b79U716TEv+nYlJaQwiJHtLbD2K4mo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B0ugh2/YyYxCzf/5jShxHLAGsE7DoJD/jM9cUnDEELU+Ji2GUSL6ok98+RQf8mw5i 5MnFZ18+NR/QpsciaCIb6ZBXvKNTkW8XsvCZLKOUM2fc3BBtDx688RaxgQ5dQTjizr qwppGUX6NoSqeJ8uulfT/uzkCVQgS93xS3axu4lt3dKMnC1tovFx38ZVs35m+52lyf AvQPkVDOu3Uik//uJih3JNYTLQCc6eAH5MBDJxcuwBt1NF0Un2tjAdyoFjVyT1/OHB BJzf0KWJAQkDGedJvAdb7M8H1u44TBIyIB0TNSi61l0tSxitowcnlWpxyiQ3ymI2QX Qigj8sWbZcmRw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Lucas De Marchi , Greg Kroah-Hartman , Rodrigo Vivi , Sasha Levin , rafael@kernel.org, dakr@kernel.org Subject: [PATCH AUTOSEL 6.6 10/23] drivers: base: devres: Allow to release group on device release Date: Thu, 3 Apr 2025 15:18:03 -0400 Message-Id: <20250403191816.2681439-10-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250403191816.2681439-1-sashal@kernel.org> References: <20250403191816.2681439-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.85 Content-Transfer-Encoding: 8bit From: Lucas De Marchi [ Upstream commit 8e1ddfada4530939a8cb64ee9251aef780474274 ] When releasing a device, if the release action causes a group to be released, a warning is emitted because it can't find the group. This happens because devres_release_all() moves the entire list to a todo list and also move the group markers. Considering r* normal resource nodes and g1 a group resource node: g1 -----------. v v r1 -> r2 -> g1[0] -> r3-> g[1] -> r4 After devres_release_all(), dev->devres_head becomes empty and the todo list it iterates on becomes: g1 v r1 -> r2 -> r3-> r4 -> g1[0] When a call to component_del() is made and takes down the aggregate device, a warning like this happen: RIP: 0010:devres_release_group+0x362/0x530 ... Call Trace: component_unbind+0x156/0x380 component_unbind_all+0x1d0/0x270 mei_component_master_unbind+0x28/0x80 [mei_hdcp] take_down_aggregate_device+0xc1/0x160 component_del+0x1c6/0x3e0 intel_hdcp_component_fini+0xf1/0x170 [xe] xe_display_fini+0x1e/0x40 [xe] Because the devres group corresponding to the hdcp component cannot be found. Just ignore this corner case: if the dev->devres_head is empty and the caller is trying to remove a group, it's likely in the process of device cleanup so just ignore it instead of warning. Acked-by: Greg Kroah-Hartman Reviewed-by: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/20250222001051.3012936-2-lucas.demarchi@intel.com Signed-off-by: Lucas De Marchi Signed-off-by: Sasha Levin --- drivers/base/devres.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/base/devres.c b/drivers/base/devres.c index e9b0d94aeabd9..8a0f000221271 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -687,6 +687,13 @@ int devres_release_group(struct device *dev, void *id) spin_unlock_irqrestore(&dev->devres_lock, flags); release_nodes(dev, &todo); + } else if (list_empty(&dev->devres_head)) { + /* + * dev is probably dying via devres_release_all(): groups + * have already been removed and are on the process of + * being released - don't touch and don't warn. + */ + spin_unlock_irqrestore(&dev->devres_lock, flags); } else { WARN_ON(1); spin_unlock_irqrestore(&dev->devres_lock, flags); -- 2.39.5