4.20-stable review patch. If anyone has any objections, please let me know.
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[ 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 --- 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 36d79b039c57..35c3aa5792e2 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;