From nobody Fri Dec 19 22:02:05 2025 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 0847E1F10D9; Sun, 24 Mar 2024 23:11:10 +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=1711321871; cv=none; b=hEGCs8gKfhSKjJdL6aIbY8Jn2PgXE70ZZDF6dZvvwkpbH68CO6DFW9WuvLmBQl3iio3rXfIrHfO9ijBCqu7egwTjwcWQnaOyDVOdQszOH4kBcy38JnB7gqv3dhqY2SvZKx11NiCPFO+mN/tUytUSsK0l1BEQPkeYIBjnldecPjA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711321871; c=relaxed/simple; bh=HF7/g01MyF5usS4jtmaXCrXMB/637THnKn0KAttJEFY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=taveYn8xUjhDT2cxpzShyN5Zrek0iIA756BWbP2oW5jbgxGFOvecifUUK/psMXyxUuH/4bUbqjY4vy0EJB3dAH08INV2TbUw1/3UmpaU9TQ2HGefe5FU5sJ5+lPIhZgBu9eZBWSpTO0ZtrJWWpYL+YKsHndpw0GO6nRIN4OcGR0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=o3M5xjxk; 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="o3M5xjxk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 309BBC433C7; Sun, 24 Mar 2024 23:11:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711321869; bh=HF7/g01MyF5usS4jtmaXCrXMB/637THnKn0KAttJEFY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=o3M5xjxk190ydVUUHx2XzsGiCM3Du8sOGkwORMiXWX5ikubqQQgla3czgj4gRdPNx fXErHd7Aj+oz5Se7nMMhtn6bYR1eK8dJYU9y1LcjaUir2t4RAoECYLhLmSx36I38vI ufe8zxGsUUDM/aEnnLfdAeH0DKmoMhSpKJOPHnQhjqn6pxn0BKCSx331IDAbk0tYbS CfMI4j1IwdhE2pdDxXZW8rjr/xUoQcc5MhBoqmL/KpCbBYYnYb6b8FNciQaXXQx0y+ 4Eshmn5s7rdl2oBT1N08iv4iY+a6M1AHL1O+chyXvRAQ35IGQwF58dVpNFe8Kd0gH7 3E6FgnW5YKhJQ== 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 6.6 598/638] xen/evtchn: avoid WARN() when unbinding an event channel Date: Sun, 24 Mar 2024 19:00:35 -0400 Message-ID: <20240324230116.1348576-599-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324230116.1348576-1-sashal@kernel.org> References: <20240324230116.1348576-1-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: quoted-printable Content-Type: text/plain; charset="utf-8" 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; }; =20 static void evtchn_free_ring(evtchn_port_t *ring) @@ -164,6 +165,10 @@ static irqreturn_t evtchn_interrupt(int irq, void *dat= a) struct per_user_data *u =3D evtchn->user; unsigned int prod, cons; =20 + /* 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_dat= a *u, =20 BUG_ON(irq < 0); =20 + evtchn->unbinding =3D true; unbind_from_irqhandler(irq, evtchn); =20 del_evtchn(u, evtchn); --=20 2.43.0