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 7AD721C5ABE; Sun, 24 Mar 2024 22:46:02 +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=1711320362; cv=none; b=jBJnTor2HxagB9BVJ0wfr002LUtt0CRhJUCWnV8iiTjeopFo5PdQmUKMZwSvQqwFM+5H66Mtm7FsCSIJR6Gixh0WTwsmr878d8fOhEZKVf07WwAJ4351JJKjpDLpSUa3qdJAUyoWHcqNtUg/8rMVQFguD5O/TATcj6IJ8f9wPh0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711320362; c=relaxed/simple; bh=HF7/g01MyF5usS4jtmaXCrXMB/637THnKn0KAttJEFY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PkXxWtolMRI+oICOyD5xR718TCX+QA+Lyh3RYBkSQ6gmXdhAZGgB6V+j7G3lDmEvFqRJP+TxzRYyb8+E04vPoUcBkgkcBFsC5/zpxAIVDfKnhQMWm2ZlV1UaUtfNX1MM8/LFnvSy8Eni/f3EFH7gJuIsca8MuioRfxsAHFP81X8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WoPsTdSG; 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="WoPsTdSG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2154C433A6; Sun, 24 Mar 2024 22:46:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711320362; bh=HF7/g01MyF5usS4jtmaXCrXMB/637THnKn0KAttJEFY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WoPsTdSGDp34Q/xZG7Z9UL33va0i+/nDc1cO+YFpwaKXKa18BdOMIkbH+6JQqsprY IAmBK3m+9AVAGLlNL/4Wo/iAhRx0nVZq4AzBhSG44/diPUO57Q84LMuyrxZt/wN3wF SiU0NRAGaAPYunxlMrk6YgCBJlcZzT9GE8OKSq3kWFXuZwLv5G58Jaaeg7Nr1+bX8+ 48SeAjJHAKezet2Byoqhd7qIJ8e5Bpd+AwGNcBBSkHjMdPrUWOP/e7KVZlRJGv8BAU vjjmHf3u2D8OEEGO+hA5WH9DOQwgY8cebutlb47+vHYbin+N1x8uBup+PU0CSZtZWH NsIgXXIrxb73w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Juergen Gross , Demi Marie Obenour , Oleksandr Tyshchenko , Sasha Levin Subject: [PATCH 6.8 669/715] xen/evtchn: avoid WARN() when unbinding an event channel Date: Sun, 24 Mar 2024 18:34:08 -0400 Message-ID: <20240324223455.1342824-670-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324223455.1342824-1-sashal@kernel.org> References: <20240324223455.1342824-1-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 Content-Transfer-Encoding: 8bit From: Juergen Gross [ Upstream commit 51c23bd691c0f1fb95b29731c356c6fd69925d17 ] When unbinding a user event channel, the related handler might be called a last time in case the kernel was built with CONFIG_DEBUG_SHIRQ. This might cause a WARN() in the handler. Avoid that by adding an "unbinding" flag to struct user_event which will short circuit the handler. Fixes: 9e90e58c11b7 ("xen: evtchn: Allow shared registration of IRQ handers") Reported-by: Demi Marie Obenour Tested-by: Demi Marie Obenour Signed-off-by: Juergen Gross Reviewed-by: Oleksandr Tyshchenko Link: https://lore.kernel.org/r/20240313071409.25913-2-jgross@suse.com Signed-off-by: Juergen Gross Signed-off-by: Sasha Levin --- drivers/xen/evtchn.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c index 59717628ca42b..f6a2216c2c870 100644 --- a/drivers/xen/evtchn.c +++ b/drivers/xen/evtchn.c @@ -85,6 +85,7 @@ struct user_evtchn { struct per_user_data *user; evtchn_port_t port; bool enabled; + bool unbinding; }; static void evtchn_free_ring(evtchn_port_t *ring) @@ -164,6 +165,10 @@ static irqreturn_t evtchn_interrupt(int irq, void *data) struct per_user_data *u = evtchn->user; unsigned int prod, cons; + /* Handler might be called when tearing down the IRQ. */ + if (evtchn->unbinding) + return IRQ_HANDLED; + WARN(!evtchn->enabled, "Interrupt for port %u, but apparently not enabled; per-user %p\n", evtchn->port, u); @@ -421,6 +426,7 @@ static void evtchn_unbind_from_user(struct per_user_data *u, BUG_ON(irq < 0); + evtchn->unbinding = true; unbind_from_irqhandler(irq, evtchn); del_evtchn(u, evtchn); -- 2.43.0