[PATCH v2 4/5] iommu/amd: Rate limit INVALID_PPR_REQUEST error logging
Vasant Hegde <[email protected]>
| Newsgroups | dev.linux.lists.iommu |
|---|---|
| Message-ID | <[email protected]> |
The amd_iommu_report_ppr_err() function logs an error message for every INVALID_PPR_REQUEST event. Under certain fault conditions, a misbehaving or malicious device can flood the IOMMU event log with PPR faults, causing the kernel log to be overwhelmed with repeated error messages. Switch from dev_err() to dev_err_ratelimited() to suppress duplicate messages when INVALID_PPR_REQUEST events occur at a high rate. Signed-off-by: Vasant Hegde <[email protected]> Reviewed-by: Ankit Soni <[email protected]> --- drivers/iommu/amd/iommu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 4372d3908e67..17df9b28ebaf 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -913,9 +913,10 @@ static void amd_iommu_report_ppr_err(struct amd_iommu *iommu, volatile u32 *even u32 pasid = PPR_PASID(*((u64 *)event)); int tag = event[1] & 0x03FF; - dev_err(dev, "Event logged [INVALID_PPR_REQUEST device=%04x:%02x:%02x.%x pasid=0x%05x address=0x%llx flags=0x%04x tag=0x%03x]\n", - iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid), - pasid, address, flags, tag); + dev_err_ratelimited(dev, "Event logged [INVALID_PPR_REQUEST device=%04x:%02x:%02x.%x " + "pasid=0x%05x address=0x%llx flags=0x%04x tag=0x%03x]\n", + iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), + PCI_FUNC(devid), pasid, address, flags, tag); /* Skip COMPLETE_PPR_REQUEST response if RX=1 */ if (flags & EVENT_FLAG_PPR_RX) -- 2.31.1