> -----Original Message----- > From: Shani Peretz <[email protected]> > Sent: Thursday, 18 September 2025 9:48 > To: [email protected] > Cc: NBU-Contact-Thomas Monjalon (EXTERNAL) <[email protected]>; > Shani Peretz <[email protected]>; [email protected]; Bruce Richardson > <[email protected]>; Dmitry Kozlyuk <[email protected]>; > Tyler Retzlaff <[email protected]>; Alejandro Lucero > <[email protected]> > Subject: [PATCH v2] eal: fix DMA mask validation inconsistency in IOVA VA > > 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: [email protected] > > Signed-off-by: Shani Peretz <[email protected]> > --- > 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
Rebased on latest main. Patch was already acked Acked-by: Anatoly Burakov <[email protected]>
