From 187fade88ca0ff2df9d360ca751d948d73db7095 Mon Sep 17 00:00:00 2001 From: Anatolij Gustschin Date: Wed, 7 Nov 2018 11:51:45 -0600 Subject: [PATCH] fpga: altera-cvp: fix 'bad IO access' on x86_64 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 Acked-by: Alan Tull Signed-off-by: Greg Kroah-Hartman --- drivers/fpga/altera-cvp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c index 610a1558e0ed..144fa2a4d4cc 100644 --- a/drivers/fpga/altera-cvp.c +++ b/drivers/fpga/altera-cvp.c @@ -477,7 +477,8 @@ 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) driver_remove_file(&altera_cvp_driver.driver, &driver_attr_chkcfg); 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;