From nobody Fri Dec 19 06:58:53 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 07C781F23FA; Sun, 24 Mar 2024 22:58:27 +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=1711321108; cv=none; b=trtPgwda58/MF9MYcmA3kPL+1DwTvRRm0V5TkSywHKreLxkPUKNdBChbqruxOTSaW+9ptYuAchrmrz93/oqZEmTE7h+kCV+levlsNlDaKBNB5Nzkol+fyNXS8vJD6cpSgUFTp7PEjDMs6naBkwKj9pFmtNzfzTgQWNoFlO6nCh4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711321108; c=relaxed/simple; bh=HF7/g01MyF5usS4jtmaXCrXMB/637THnKn0KAttJEFY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CD6r74XjCc/tpWeIKNuMo+7uxwAxD4IX1jTaa9DwJ2JA9d3y1Nw9kwgQbKRe+1eVyR1hw+Vk9uxTMJR6+ha8/z2lnPM3/Ey62QagOel43YTuAyUc9zWjMCeOwoKLMEpyWWHUDxsAsu4eSof4f8lBVrlDUSimVyCFmB4dvhuPgwM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=J1v77yAS; 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="J1v77yAS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C4BBC43390; Sun, 24 Mar 2024 22:58:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711321106; bh=HF7/g01MyF5usS4jtmaXCrXMB/637THnKn0KAttJEFY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J1v77yASM7g7c/v2nLvAx+6IdkKTUe/1v/vDlWcc9eKERChh9bXg2nXyu9W8URety 5DFDo+OqHfSu8gYUcFOUINLkyESQrlqSZqC0mSR8bvk7MaQjZh6QxXNZag8YQhAU4f GcmzfGx3zFQwtlViSZESmOaBTCV1OtuBGRiPmPhexV4dD0IGoHKDTHU2PEEXiBMGPF F8oOrcWW8o8zxdqtJ48wE1PWJI4bcvFsS+VsZtRSUJSn2a+9t/t52aRtr6tzftLnV3 sTaDyRKwWnEDr2sbt/8dB54METDphwMC0hmE0yJCmOO1TIUyuI2pit540XhVrUYuOO Zfj4HmCEUtxvA== 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 6.7 669/713] xen/evtchn: avoid WARN() when unbinding an event channel Date: Sun, 24 Mar 2024 18:46:35 -0400 Message-ID: <20240324224720.1345309-670-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324224720.1345309-1-sashal@kernel.org> References: <20240324224720.1345309-1-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