From 951ebc18d181af1d90deddbc0ef3269061d6e03c Mon Sep 17 00:00:00 2001 From: Matt Evans Date: Thu, 23 Apr 2026 10:30:51 -0700 Subject: [PATCH 1/2] PCI/P2PDMA: Avoid returning a provider for non_mappable_bars Extend the checks in pcim_p2pdma_init() and pcim_p2pdma_provider() to exclude functions that have pdev->non_mappable_bars set. Consumers such as VFIO were previously able to map these for access by the CPU or P2P. Update the comment on non_mappable_bars to show it refers to any access, not just userspace CPU access. Fixes: 372d6d1b8ae3c ("PCI/P2PDMA: Refactor to separate core P2P functionality from memory allocation") Suggested-by: Alex Williamson Signed-off-by: Matt Evans Signed-off-by: Bjorn Helgaas Reviewed-by: Niklas Schnelle Reviewed-by: Alex Williamson Link: https://patch.msgid.link/20260423173051.1999679-1-mattev@meta.com --- drivers/pci/p2pdma.c | 6 +++++- include/linux/pci.h | 2 +- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 7c898542af8d..adb17a4f6939 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -262,6 +262,9 @@ int pcim_p2pdma_init(struct pci_dev *pdev) struct pci_p2pdma *p2p; int i, ret; + if (pdev->non_mappable_bars) + return -EOPNOTSUPP; + p2p = rcu_dereference_protected(pdev->p2pdma, 1); if (p2p) return 0; @@ -318,7 +321,8 @@ struct p2pdma_provider *pcim_p2pdma_provider(struct pci_dev *pdev, int bar) { struct pci_p2pdma *p2p; - if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) + if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM) || + pdev->non_mappable_bars) return NULL; p2p = rcu_dereference_protected(pdev->p2pdma, 1); diff --git a/include/linux/pci.h b/include/linux/pci.h index 2c4454583c11..1e6802017d6b 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -508,7 +508,7 @@ struct pci_dev { unsigned int no_command_memory:1; /* No PCI_COMMAND_MEMORY */ unsigned int rom_bar_overlap:1; /* ROM BAR disable broken */ unsigned int rom_attr_enabled:1; /* Display of ROM attribute enabled? */ - unsigned int non_mappable_bars:1; /* BARs can't be mapped to user-space */ + unsigned int non_mappable_bars:1; /* BARs can't be mapped by CPU or peers */ pci_dev_flags_t dev_flags; atomic_t enable_cnt; /* pci_enable_device has been called */ From 0ba76b19fd4c7256787eab0283c759b18eb76876 Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Thu, 4 Jun 2026 17:12:08 +0200 Subject: [PATCH 2/2] PCI/P2PDMA: Add Intel QAT, DSA, IAA devices to whitelist The first device on a PCI root bus determines whether the host bridge is whitelisted for P2PDMA. All Intel Xeon chips since Ice Lake (ICX, 2021) expose a device with ID 0x09a2 as first device. It is loosely associated with the IOMMU. All these Xeon chips support P2PDMA, so since the addition of the device with commit feaea1fe8b36 ("PCI/P2PDMA: Add Intel 3rd Gen Intel Xeon Scalable Processors to whitelist"), P2PDMA has been allowed on all new Xeons without the need to amend the whitelist: Xeons with Performance Cores: Sapphire Rapids (SPR, 2023) Emerald Rapids (EMR, 2023) Granite Rapids (GNR, 2024) Diamond Rapids (DMR, 2026) Xeons with Efficiency Cores: Sierra Forest (SRF, 2024) Clearwater Forest (CWF, 2026) However these Xeons also expose accelerators as first device on a root bus of its own: QuickAssist Technology (QAT, crypto & compression accelerator) Data Streaming Accelerator (DSA, dma engine) In-Memory Analytics Accelerator (IAA, compression accelerator) Whitelist them for P2PDMA as well. Move their Device ID macros from the accelerator drivers to for reuse by P2PDMA code. Unfortunately the Device IDs vary across Xeon generations as additional features were added to the accelerators. This currently necessitates an amendment for each new Xeon chip. For future chips, this need shall be avoided by an ongoing effort to extend ACPI HMAT with PCIe P2PDMA characteristics (latency, bandwidth, ordering constraints). The PCI core will be able look up in this BIOS-provided ACPI table whether P2PDMA is supported, instead of relying on a whitelist that needs to be amended continuously. Signed-off-by: Lukas Wunner Signed-off-by: Bjorn Helgaas Acked-by: Vinicius Costa Gomes Acked-by: Giovanni Cabiddu # QAT Cc: stable@vger.kernel.org Link: https://patch.msgid.link/6aac4922b5fe7070b11874427a9285e42ddd05a4.1780585518.git.lukas@wunner.de --- .../crypto/intel/qat/qat_common/adf_accel_devices.h | 5 ----- drivers/dma/idxd/registers.h | 3 --- drivers/pci/p2pdma.c | 10 ++++++++++ include/linux/pci_ids.h | 8 ++++++++ 4 files changed, 18 insertions(+), 8 deletions(-) diff --git a/drivers/crypto/intel/qat/qat_common/adf_accel_devices.h b/drivers/crypto/intel/qat/qat_common/adf_accel_devices.h index 03a4e9690208..cbd1d1eda5a3 100644 --- a/drivers/crypto/intel/qat/qat_common/adf_accel_devices.h +++ b/drivers/crypto/intel/qat/qat_common/adf_accel_devices.h @@ -28,15 +28,10 @@ #define ADF_4XXX_DEVICE_NAME "4xxx" #define ADF_420XX_DEVICE_NAME "420xx" #define ADF_6XXX_DEVICE_NAME "6xxx" -#define PCI_DEVICE_ID_INTEL_QAT_4XXX 0x4940 #define PCI_DEVICE_ID_INTEL_QAT_4XXXIOV 0x4941 -#define PCI_DEVICE_ID_INTEL_QAT_401XX 0x4942 #define PCI_DEVICE_ID_INTEL_QAT_401XXIOV 0x4943 -#define PCI_DEVICE_ID_INTEL_QAT_402XX 0x4944 #define PCI_DEVICE_ID_INTEL_QAT_402XXIOV 0x4945 -#define PCI_DEVICE_ID_INTEL_QAT_420XX 0x4946 #define PCI_DEVICE_ID_INTEL_QAT_420XXIOV 0x4947 -#define PCI_DEVICE_ID_INTEL_QAT_6XXX 0x4948 #define PCI_DEVICE_ID_INTEL_QAT_6XXX_IOV 0x4949 #define ADF_DEVICE_FUSECTL_OFFSET 0x40 diff --git a/drivers/dma/idxd/registers.h b/drivers/dma/idxd/registers.h index f95411363ea9..1dce26d4da83 100644 --- a/drivers/dma/idxd/registers.h +++ b/drivers/dma/idxd/registers.h @@ -10,9 +10,6 @@ #endif /* PCI Config */ -#define PCI_DEVICE_ID_INTEL_DSA_GNRD 0x11fb -#define PCI_DEVICE_ID_INTEL_DSA_DMR 0x1212 -#define PCI_DEVICE_ID_INTEL_IAA_DMR 0x1216 #define PCI_DEVICE_ID_INTEL_IAA_PTL 0xb02d #define PCI_DEVICE_ID_INTEL_IAA_WCL 0xfd2d diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index adb17a4f6939..b2d5266f8653 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -552,6 +552,16 @@ static const struct pci_p2pdma_whitelist_entry { {PCI_VENDOR_ID_INTEL, 0x2033, 0}, {PCI_VENDOR_ID_INTEL, 0x2020, 0}, {PCI_VENDOR_ID_INTEL, 0x09a2, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DSA_SPR0, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IAX_SPR0, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DSA_GNRD, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DSA_DMR, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IAA_DMR, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_QAT_4XXX, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_QAT_401XX, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_QAT_402XX, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_QAT_420XX, 0}, + {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_QAT_6XXX, 0}, /* Google SoCs. */ {PCI_VENDOR_ID_GOOGLE, PCI_ANY_ID, 0}, {} diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h index 24cb42f66e4b..1c9d40e09107 100644 --- a/include/linux/pci_ids.h +++ b/include/linux/pci_ids.h @@ -2732,6 +2732,9 @@ #define PCI_DEVICE_ID_INTEL_82815_MC 0x1130 #define PCI_DEVICE_ID_INTEL_82815_CGC 0x1132 #define PCI_DEVICE_ID_INTEL_SST_TNG 0x119a +#define PCI_DEVICE_ID_INTEL_DSA_GNRD 0x11fb +#define PCI_DEVICE_ID_INTEL_DSA_DMR 0x1212 +#define PCI_DEVICE_ID_INTEL_IAA_DMR 0x1216 #define PCI_DEVICE_ID_INTEL_82092AA_0 0x1221 #define PCI_DEVICE_ID_INTEL_82437 0x122d #define PCI_DEVICE_ID_INTEL_82371FB_0 0x122e @@ -3052,6 +3055,11 @@ #define PCI_DEVICE_ID_INTEL_5400_FBD1 0x4036 #define PCI_DEVICE_ID_INTEL_HDA_TGL_H 0x43c8 #define PCI_DEVICE_ID_INTEL_HDA_DG1 0x490d +#define PCI_DEVICE_ID_INTEL_QAT_4XXX 0x4940 +#define PCI_DEVICE_ID_INTEL_QAT_401XX 0x4942 +#define PCI_DEVICE_ID_INTEL_QAT_402XX 0x4944 +#define PCI_DEVICE_ID_INTEL_QAT_420XX 0x4946 +#define PCI_DEVICE_ID_INTEL_QAT_6XXX 0x4948 #define PCI_DEVICE_ID_INTEL_HDA_EHL_0 0x4b55 #define PCI_DEVICE_ID_INTEL_HDA_EHL_3 0x4b58 #define PCI_DEVICE_ID_INTEL_HDA_WCL 0x4d28