From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: From: Alan Tull Subject: [PATCH 1/4] fpga: altera-cvp: fix 'bad IO access' on x86_64 Date: Wed, 7 Nov 2018 11:51:45 -0600 Message-Id: <1541613108-29660-2-git-send-email-atull@kernel.org> In-Reply-To: <1541613108-29660-1-git-send-email-atull@kernel.org> References: <1541613108-29660-1-git-send-email-atull@kernel.org> To: Greg Kroah-Hartman Cc: Moritz Fischer , Alan Tull , linux-kernel@vger.kernel.org, linux-fpga@vger.kernel.org, Anatolij Gustschin List-ID: From: Anatolij Gustschin 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 --- 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 610a155..144fa2a 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; -- 2.7.4