Messages in this thread | | | Subject | Re: [PATCH 0/2] iommu/dmar: expose fault counters via sysfs | From | Lu Baolu <> | Date | Wed, 16 Oct 2019 08:45:55 +0800 |
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Hi,
On 10/15/19 11:11 PM, Yuri Volchkov wrote: > For health monitoring, it can be useful to know if iommu is behaving as > expected. DMAR faults can be an indicator that a device: > - has been misconfigured, or > - has experienced a hardware hiccup and replacement should > be considered, or > - has been issuing faults due to malicious activity > > Currently the only way to check if there were any DMAR faults on the > host is to scan the dmesg output. However this approach is not very > elegant. The information we are looking for can be wrapped out of the > buffer, or masked (since it is a rate-limited print) by another > device. > > The series adds counters for DMAR faults and exposes them via sysfs. >
We now have an iommu API named iommu_register_fault_handler() to register callbacks for dmar faults. How about monitoring the dmar fault through this api so that your code could be generic and vendor agnostic?
Best regards, Baolu
> Yuri Volchkov (2): > iommu/dmar: collect fault statistics > iommu/dmar: catch early fault occurrences > > drivers/iommu/dmar.c | 182 ++++++++++++++++++++++++++++++++---- > drivers/iommu/intel-iommu.c | 1 + > drivers/pci/pci-sysfs.c | 20 ++++ > include/linux/intel-iommu.h | 4 + > include/linux/pci.h | 11 +++ > 5 files changed, 201 insertions(+), 17 deletions(-) >
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