<div dir="ltr">FYI The DTS failure for this series on patchwork for the MTU testsuite is coming from a different patch than this one. Once I have that resolved, I will put in a retest for this series which will clear up that MTU testsuite failure.</div> <div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Mon, Sep 8, 2025 at 12:35 PM Shani Peretz <<a href="mailto:shperetz@nvidia.com">shperetz@nvidia.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">When --iova-mode is explicitly specified in command line, DMA mask constraints were not being validated, leading to potential runtime failures when device DMA capabilities are exceeded. The issue occurred because rte_bus_get_iommu_class() was only called during IOVA mode auto-detection, but this function has the important side effect of triggering DMA mask detection (e.g., Intel IOMMU address width checking via pci_device_iommu_support_va()). This created an inconsistency, when choosing explicit mode, the DMA checks are bypassed, but when choosing auto-detection mode, the constraints are checked and enforced. The fix moves rte_bus_get_iommu_class() outside the conditional logic to ensure it's always called during EAL initialization. Fixes: 4374ebc24bc1 ("malloc: modify error message for DMA mask check") Cc: <a href="mailto:stable@dpdk.org" target="_blank">stable@dpdk.org</a> Signed-off-by: Shani Peretz <<a href="mailto:shperetz@nvidia.com" target="_blank">shperetz@nvidia.com</a>> --- lib/eal/freebsd/eal.c | 6 +++++- lib/eal/linux/eal.c | 5 ++++- lib/eal/windows/eal.c | 5 ++++- 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/lib/eal/freebsd/eal.c b/lib/eal/freebsd/eal.c index c1ab8d86d2..0f957919d3 100644 --- a/lib/eal/freebsd/eal.c +++ b/lib/eal/freebsd/eal.c @@ -670,12 +670,16 @@ rte_eal_init(int argc, char **argv) * with a message describing the cause. */ has_phys_addr = internal_conf->no_hugetlbfs == 0; + + /* Always call rte_bus_get_iommu_class() to trigger DMA mask detection and validation */ + enum rte_iova_mode bus_iova_mode = rte_bus_get_iommu_class(); + iova_mode = internal_conf->iova_mode; if (iova_mode == RTE_IOVA_DC) { EAL_LOG(DEBUG, "Specific IOVA mode is not requested, autodetecting"); if (has_phys_addr) { EAL_LOG(DEBUG, "Selecting IOVA mode according to bus requests"); - iova_mode = rte_bus_get_iommu_class(); + iova_mode = bus_iova_mode; if (iova_mode == RTE_IOVA_DC) { if (!RTE_IOVA_IN_MBUF) { iova_mode = RTE_IOVA_VA; diff --git a/lib/eal/linux/eal.c b/lib/eal/linux/eal.c index 52efb8626b..3a0c9c9db6 100644 --- a/lib/eal/linux/eal.c +++ b/lib/eal/linux/eal.c @@ -1042,10 +1042,13 @@ rte_eal_init(int argc, char **argv) phys_addrs = rte_eal_using_phys_addrs() != 0; + /* Always call rte_bus_get_iommu_class() to trigger DMA mask detection and validation */ + enum rte_iova_mode bus_iova_mode = rte_bus_get_iommu_class(); + /* if no EAL option "--iova-mode=<pa|va>", use bus IOVA scheme */ if (internal_conf->iova_mode == RTE_IOVA_DC) { /* autodetect the IOVA mapping mode */ - enum rte_iova_mode iova_mode = rte_bus_get_iommu_class(); + enum rte_iova_mode iova_mode = bus_iova_mode; if (iova_mode == RTE_IOVA_DC) { EAL_LOG(DEBUG, "Buses did not request a specific IOVA mode."); diff --git a/lib/eal/windows/eal.c b/lib/eal/windows/eal.c index 4f0a164d9b..2502ec3c3d 100644 --- a/lib/eal/windows/eal.c +++ b/lib/eal/windows/eal.c @@ -348,12 +348,15 @@ rte_eal_init(int argc, char **argv) has_phys_addr = false; } + /* Always call rte_bus_get_iommu_class() to trigger DMA mask detection and validation */ + enum rte_iova_mode bus_iova_mode = rte_bus_get_iommu_class(); + iova_mode = internal_conf->iova_mode; if (iova_mode == RTE_IOVA_DC) { EAL_LOG(DEBUG, "Specific IOVA mode is not requested, autodetecting"); if (has_phys_addr) { EAL_LOG(DEBUG, "Selecting IOVA mode according to bus requests"); - iova_mode = rte_bus_get_iommu_class(); + iova_mode = bus_iova_mode; if (iova_mode == RTE_IOVA_DC) { if (!RTE_IOVA_IN_MBUF) { iova_mode = RTE_IOVA_VA; -- 2.34.1 </blockquote></div>