Hi Jacob, On 9/21/18 12:06 AM, Jacob Pan wrote: > On Tue, 18 Sep 2018 16:24:51 +0200 > Eric Auger <eric.auger@xxxxxxxxxx> wrote: > >> From: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> >> >> Device faults detected by IOMMU can be reported outside IOMMU >> subsystem for further processing. This patch intends to provide >> a generic device fault data such that device drivers can be >> communicated with IOMMU faults without model specific knowledge. >> >> The proposed format is the result of discussion at: >> https://lkml.org/lkml/2017/11/10/291 >> Part of the code is based on Jean-Philippe Brucker's patchset >> (https://patchwork.kernel.org/patch/9989315/). >> >> The assumption is that model specific IOMMU driver can filter and >> handle most of the internal faults if the cause is within IOMMU driver >> control. Therefore, the fault reasons can be reported are grouped >> and generalized based common specifications such as PCI ATS. >> >> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> >> Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx> >> Signed-off-by: Liu, Yi L <yi.l.liu@xxxxxxxxxxxxxxx> >> Signed-off-by: Ashok Raj <ashok.raj@xxxxxxxxx> >> Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> >> [moved part of the iommu_fault_event struct in the uapi, enriched >> the fault reasons to be able to map unrecoverable SMMUv3 errors] > Sounds good to me. > There are also other "enrichment" we need to do to support mdev or > finer granularity fault reporting below physical device. e.g. PASID > level. > > The current scheme works for PCIe physical device level, where each > device registers a single handler only once. When device fault is > detected by the IOMMU, it will find the matching handler and private > data to report back. However, for devices partitioned by PASID and > represented by mdev this may not work. Since IOMMU is not mdev aware > and only works at physical device level. > So I am thinking we should allow multiple registration of fault handler > with different data and ID. i.e. > > int iommu_register_device_fault_handler(struct device *dev, > iommu_dev_fault_handler_t handler, > int id, > void *data) > > where the new "id field" is > * @id: Identification of the handler private data, will be used by fault > * reporting code to match the handler data to be returned. For page > * request, this can be the PASID. ID must be unique per device, i.e. > * each ID can only be registered once per device. > * - IOMMU_DEV_FAULT_ID_UNRECOVERY (~0U) is reserved for fault reporting > * w/o ID. e.g. unrecoverable faults. > > I am still testing, but just wanted to have feedback on this idea. I am currently respinning this series. Do you have a respin for this patch including iommu_register_device_fault_handler with the @id param as you suggested above? Otherwise 2 solutions: I keep the code as is or I do the modification myself implementing a list of fault_params? Besides do you plans for "[PATCH v5 00/23] IOMMU and VT-d driver support for Shared Virtual Address (SVA)" respin - hope I didn't miss anything? - ? Thanks Eric > > Thanks, > > Jacob > > >> --- >> include/linux/iommu.h | 55 ++++++++++++++++++++++++- >> include/uapi/linux/iommu.h | 83 >> ++++++++++++++++++++++++++++++++++++++ 2 files changed, 136 >> insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/iommu.h b/include/linux/iommu.h >> index 9bd3e63d562b..7529c14ff506 100644 >> --- a/include/linux/iommu.h >> +++ b/include/linux/iommu.h >> @@ -49,13 +49,17 @@ struct bus_type; >> struct device; >> struct iommu_domain; >> struct notifier_block; >> +struct iommu_fault_event; >> >> /* iommu fault flags */ >> -#define IOMMU_FAULT_READ 0x0 >> -#define IOMMU_FAULT_WRITE 0x1 >> +#define IOMMU_FAULT_READ (1 << 0) >> +#define IOMMU_FAULT_WRITE (1 << 1) >> +#define IOMMU_FAULT_EXEC (1 << 2) >> +#define IOMMU_FAULT_PRIV (1 << 3) >> >> typedef int (*iommu_fault_handler_t)(struct iommu_domain *, >> struct device *, unsigned long, int, void *); >> +typedef int (*iommu_dev_fault_handler_t)(struct iommu_fault_event *, >> void *); >> struct iommu_domain_geometry { >> dma_addr_t aperture_start; /* First address that can be >> mapped */ @@ -262,6 +266,52 @@ struct iommu_device { >> struct device *dev; >> }; >> >> +/** >> + * struct iommu_fault_event - Generic per device fault data >> + * >> + * - PCI and non-PCI devices >> + * - Recoverable faults (e.g. page request), information based on >> PCI ATS >> + * and PASID spec. >> + * - Un-recoverable faults of device interest >> + * - DMA remapping and IRQ remapping faults >> + * >> + * @fault: fault descriptor >> + * @device_private: if present, uniquely identify device-specific >> + * private data for an individual page request. >> + * @iommu_private: used by the IOMMU driver for storing >> fault-specific >> + * data. Users should not modify this field before >> + * sending the fault response. >> + */ >> +struct iommu_fault_event { >> + struct iommu_fault fault; >> + u64 device_private; >> + u64 iommu_private; >> +}; >> + >> +/** >> + * struct iommu_fault_param - per-device IOMMU fault data >> + * @dev_fault_handler: Callback function to handle IOMMU faults at >> device level >> + * @data: handler private data >> + * >> + */ >> +struct iommu_fault_param { >> + iommu_dev_fault_handler_t handler; >> + void *data; >> +}; >> + >> +/** >> + * struct iommu_param - collection of per-device IOMMU data >> + * >> + * @fault_param: IOMMU detected device fault reporting data >> + * >> + * TODO: migrate other per device data pointers under >> iommu_dev_data, e.g. >> + * struct iommu_group *iommu_group; >> + * struct iommu_fwspec *iommu_fwspec; >> + */ >> +struct iommu_param { >> + struct iommu_fault_param *fault_param; >> +}; >> + >> int iommu_device_register(struct iommu_device *iommu); >> void iommu_device_unregister(struct iommu_device *iommu); >> int iommu_device_sysfs_add(struct iommu_device *iommu, >> @@ -429,6 +479,7 @@ struct iommu_ops {}; >> struct iommu_group {}; >> struct iommu_fwspec {}; >> struct iommu_device {}; >> +struct iommu_fault_param {}; >> >> static inline bool iommu_present(struct bus_type *bus) >> { >> diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h >> index 21adb2a964e5..a0fe5c2fb236 100644 >> --- a/include/uapi/linux/iommu.h >> +++ b/include/uapi/linux/iommu.h >> @@ -150,5 +150,88 @@ struct iommu_guest_msi_binding { >> __u64 gpa; >> __u32 granule; >> }; >> + >> +/* Generic fault types, can be expanded IRQ remapping fault */ >> +enum iommu_fault_type { >> + IOMMU_FAULT_DMA_UNRECOV = 1, /* unrecoverable fault */ >> + IOMMU_FAULT_PAGE_REQ, /* page request fault */ >> +}; >> + >> +enum iommu_fault_reason { >> + IOMMU_FAULT_REASON_UNKNOWN = 0, >> + >> + /* IOMMU internal error, no specific reason to report out */ >> + IOMMU_FAULT_REASON_INTERNAL, >> + >> + /* Could not access the PASID table (fetch caused external >> abort) */ >> + IOMMU_FAULT_REASON_PASID_FETCH, >> + >> + /* could not access the device context (fetch caused >> external abort) */ >> + IOMMU_FAULT_REASON_DEVICE_CONTEXT_FETCH, >> + >> + /* pasid entry is invalid or has configuration errors */ >> + IOMMU_FAULT_REASON_BAD_PASID_ENTRY, >> + >> + /* device context entry is invalid or has configuration >> errors */ >> + IOMMU_FAULT_REASON_BAD_DEVICE_CONTEXT_ENTRY, >> + /* >> + * PASID is out of range (e.g. exceeds the maximum PASID >> + * supported by the IOMMU) or disabled. >> + */ >> + IOMMU_FAULT_REASON_PASID_INVALID, >> + >> + /* source id is out of range */ >> + IOMMU_FAULT_REASON_SOURCEID_INVALID, >> + >> + /* >> + * An external abort occurred fetching (or updating) a >> translation >> + * table descriptor >> + */ >> + IOMMU_FAULT_REASON_WALK_EABT, >> + >> + /* >> + * Could not access the page table entry (Bad address), >> + * actual translation fault >> + */ >> + IOMMU_FAULT_REASON_PTE_FETCH, >> + >> + /* Protection flag check failed */ >> + IOMMU_FAULT_REASON_PERMISSION, >> + >> + /* access flag check failed */ >> + IOMMU_FAULT_REASON_ACCESS, >> + >> + /* Output address of a translation stage caused Address Size >> fault */ >> + IOMMU_FAULT_REASON_OOR_ADDRESS >> +}; >> + >> +/** >> + * struct iommu_fault - Generic fault data >> + * >> + * @type contains fault type >> + * @reason fault reasons if relevant outside IOMMU driver. >> + * IOMMU driver internal faults are not reported. >> + * @addr: tells the offending page address >> + * @fetch_addr: tells the address that caused an abort, if any >> + * @pasid: contains process address space ID, used in shared virtual >> memory >> + * @page_req_group_id: page request group index >> + * @last_req: last request in a page request group >> + * @pasid_valid: indicates if the PRQ has a valid PASID >> + * @prot: page access protection flag: >> + * IOMMU_FAULT_READ, IOMMU_FAULT_WRITE >> + */ >> + >> +struct iommu_fault { >> + __u32 type; /* enum iommu_fault_type */ >> + __u32 reason; /* enum iommu_fault_reason */ >> + __u64 addr; >> + __u64 fetch_addr; >> + __u32 pasid; >> + __u32 page_req_group_id; >> + __u32 last_req; >> + __u32 pasid_valid; >> + __u32 prot; >> + __u32 access; >> +}; >> #endif /* _UAPI_IOMMU_H */ >> > > [Jacob Pan] >
