From: Anatolij Gustschin <agust@denx.de>
Date: Wed, 7 Nov 2018 17:51:45 +0000 (-0600)
Subject: fpga: altera-cvp: fix 'bad IO access' on x86_64
X-Git-Tag: v4.20.8~307
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=8c5d16583a2a5062113f9ae132449391c1b99314;p=users%2Fdwmw2%2Flinux.git

fpga: altera-cvp: fix 'bad IO access' on x86_64

[ Upstream commit 187fade88ca0ff2df9d360ca751d948d73db7095 ]

If mapping the CvP BAR fails, we still can configure the FPGA via
PCI config space access. In this case the iomap pointer is NULL.
On x86_64, passing NULL address to pci_iounmap() generates
"Bad IO access at port 0x0" output with stack call trace. Fix it.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
index 36d79b039c57d..35c3aa5792e26 100644
--- a/drivers/fpga/altera-cvp.c
+++ b/drivers/fpga/altera-cvp.c
@@ -478,7 +478,8 @@ static int altera_cvp_probe(struct pci_dev *pdev,
 	return 0;
 
 err_unmap:
-	pci_iounmap(pdev, conf->map);
+	if (conf->map)
+		pci_iounmap(pdev, conf->map);
 	pci_release_region(pdev, CVP_BAR);
 err_disable:
 	cmd &= ~PCI_COMMAND_MEMORY;
@@ -493,7 +494,8 @@ static void altera_cvp_remove(struct pci_dev *pdev)
 	u16 cmd;
 
 	fpga_mgr_unregister(mgr);
-	pci_iounmap(pdev, conf->map);
+	if (conf->map)
+		pci_iounmap(pdev, conf->map);
 	pci_release_region(pdev, CVP_BAR);
 	pci_read_config_word(pdev, PCI_COMMAND, &cmd);
 	cmd &= ~PCI_COMMAND_MEMORY;