From 18aacd95fed8f3f7c54cb39bb8d0cf6d66fdf996 Mon Sep 17 00:00:00 2001 From: Niklas Schnelle Date: Thu, 27 Feb 2020 12:17:18 +0100 Subject: [PATCH] s390/pci: Fix unexpected write combine on resource In the initial MIO support introduced in commit b5837ab9558d ("s390/pci: provide support for MIO instructions") zpci_map_resource() and zpci_setup_resources() default to using the mio_wb address as the resource's start address. This means users of the mapping, which includes most drivers, will get write combining on PCI Stores. This may lead to problems when drivers expect write through behavior when not using an explicit ioremap_wc(). Cc: stable@vger.kernel.org Fixes: b5837ab9558d ("s390/pci: provide support for MIO instructions") Signed-off-by: Niklas Schnelle Reviewed-by: Pierre Morel Signed-off-by: Vasily Gorbik --- arch/s390/pci/pci.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c index bc61ea18e88d9..60716d18ce5af 100644 --- a/arch/s390/pci/pci.c +++ b/arch/s390/pci/pci.c @@ -424,7 +424,7 @@ static void zpci_map_resources(struct pci_dev *pdev) if (zpci_use_mio(zdev)) pdev->resource[i].start = - (resource_size_t __force) zdev->bars[i].mio_wb; + (resource_size_t __force) zdev->bars[i].mio_wt; else pdev->resource[i].start = (resource_size_t __force) pci_iomap_range_fh(pdev, i, 0, 0); @@ -531,7 +531,7 @@ static int zpci_setup_bus_resources(struct zpci_dev *zdev, flags |= IORESOURCE_MEM_64; if (zpci_use_mio(zdev)) - addr = (unsigned long) zdev->bars[i].mio_wb; + addr = (unsigned long) zdev->bars[i].mio_wt; else addr = ZPCI_ADDR(entry); size = 1UL << zdev->bars[i].size; -- 2.39.5