From aa8604fe63d1441eb49ead16d7e87ee03e4b1ece Mon Sep 17 00:00:00 2001 From: Moritz Fischer Date: Thu, 21 Jan 2021 17:24:19 -0800 Subject: [PATCH] ACPI/IORT: Do not blindly trust DMA masks from firmware [ Upstream commit a1df829ead5877d4a1061e976a50e2e665a16f24 ] Address issue observed on real world system with suboptimal IORT table where DMA masks of PCI devices would get set to 0 as result. iort_dma_setup() would query the root complex'/named component IORT entry for a DMA mask, and use that over the one the device has been configured with earlier. Ideally we want to use the minimum mask of what the IORT contains for the root complex and what the device was configured with. Fixes: 5ac65e8c8941 ("ACPI/IORT: Support address size limit for root complexes") Signed-off-by: Moritz Fischer Reviewed-by: Robin Murphy Acked-by: Lorenzo Pieralisi Link: https://lore.kernel.org/r/20210122012419.95010-1-mdf@kernel.org Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin --- drivers/acpi/arm64/iort.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 770d84071a32..94f34109695c 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -1107,6 +1107,11 @@ static int nc_dma_get_range(struct device *dev, u64 *size) ncomp = (struct acpi_iort_named_component *)node->node_data; + if (!ncomp->memory_address_limit) { + pr_warn(FW_BUG "Named component missing memory address limit\n"); + return -EINVAL; + } + *size = ncomp->memory_address_limit >= 64 ? U64_MAX : 1ULL<memory_address_limit; @@ -1126,6 +1131,11 @@ static int rc_dma_get_range(struct device *dev, u64 *size) rc = (struct acpi_iort_root_complex *)node->node_data; + if (!rc->memory_address_limit) { + pr_warn(FW_BUG "Root complex missing memory address limit\n"); + return -EINVAL; + } + *size = rc->memory_address_limit >= 64 ? U64_MAX : 1ULL<memory_address_limit; @@ -1173,8 +1183,8 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) end = dmaaddr + size - 1; mask = DMA_BIT_MASK(ilog2(end) + 1); dev->bus_dma_limit = end; - dev->coherent_dma_mask = mask; - *dev->dma_mask = mask; + dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask); + *dev->dma_mask = min(*dev->dma_mask, mask); } *dma_addr = dmaaddr;