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 7361511706 for ; Mon, 11 Sep 2023 14:45:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EB93EC433C8; Mon, 11 Sep 2023 14:45:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694443548; bh=rwsAi/4lJgletn2hMJ9P43Qxh8Eau3ojl4dLI7kvBP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sxUw+fgAvjeTLdB3Z3V+YCc6rfm5rN6ZGXhb4+iWJhEdLPhFoh/ceJmGK+h7TkwpH z1fxoqwOYeCPM7QZWlJeu1fxhYpK8Nul6RisJryDozKAL1qIyvqQYr59rCa7SsJ77v 6WEcRukPd42NBm0PIPRhtUXZs4Z5IqXP3CEBfOyo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sven Peter , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Marc Zyngier , Alyssa Rosenzweig , Eric Curtin , Sasha Levin Subject: [PATCH 6.4 416/737] PCI: apple: Initialize pcie->nvecs before use Date: Mon, 11 Sep 2023 15:44:35 +0200 Message-ID: <20230911134702.233184689@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230911134650.286315610@linuxfoundation.org> References: <20230911134650.286315610@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Peter [ Upstream commit d8650c0c2aa2e413594e4cb0faafa9958c1d7782 ] The apple_pcie_setup_port() function computes ilog2(pcie->nvecs) to set up the number of MSIs available for each port. However, it's called before apple_msi_init(), which initializes pcie->nvecs. Luckily, pcie->nvecs is part of kzalloc()-ed structure and, as such, initialized as zero. ilog2(0) happens to be 0xffffffff which then simply configures more MSIs in hardware than we have. This doesn't break anything because we never hand out those vectors. Thus, swap the order of the two calls so that the correctly initialized value is then used. [kwilczynski: commit log] Link: https://lore.kernel.org/linux-pci/20230311133453.63246-1-sven@svenpeter.dev Fixes: 476c41ed4597 ("PCI: apple: Implement MSI support") Signed-off-by: Sven Peter Signed-off-by: Krzysztof Wilczyński Reviewed-by: Marc Zyngier Reviewed-by: Alyssa Rosenzweig Reviewed-by: Eric Curtin Signed-off-by: Sasha Levin --- drivers/pci/controller/pcie-apple.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c index 66f37e403a09c..2340dab6cd5bd 100644 --- a/drivers/pci/controller/pcie-apple.c +++ b/drivers/pci/controller/pcie-apple.c @@ -783,6 +783,10 @@ static int apple_pcie_init(struct pci_config_window *cfg) cfg->priv = pcie; INIT_LIST_HEAD(&pcie->ports); + ret = apple_msi_init(pcie); + if (ret) + return ret; + for_each_child_of_node(dev->of_node, of_port) { ret = apple_pcie_setup_port(pcie, of_port); if (ret) { @@ -792,7 +796,7 @@ static int apple_pcie_init(struct pci_config_window *cfg) } } - return apple_msi_init(pcie); + return 0; } static int apple_pcie_probe(struct platform_device *pdev) -- 2.40.1