Re: [PATCH v6 14/16] PCI/AER: Introduce ratelimit for error logs

On Mon, May 19, 2025 at 09:59:29PM -0700, Sathyanarayanan Kuppuswamy wrote:

On 5/19/25 2:35 PM, Bjorn Helgaas wrote:

quoted

From: Jon Pan-Doh <redacted>

Spammy devices can flood kernel logs with AER errors and slow/stall
execution. Add per-device ratelimits for AER correctable and uncorrectable
errors that use the kernel defaults (10 per 5s).

There are two AER logging entry points:

   - aer_print_error() is used by DPC and native AER

   - pci_print_aer() is used by GHES and CXL

The native AER aer_print_error() case includes a loop that may log details
from multiple devices.  This is ratelimited by the union of ratelimits for
these devices, set by add_error_device(), which collects the devices.  If
no such device is found, the Error Source message is ratelimited by the
Root Port or RCEC that received the ERR_* message.

The DPC aer_print_error() case is currently not ratelimited.

Can we also not rate limit fatal errors in AER driver?

In other words, only rate limit AER_CORRECTABLE and AER_NONFATAL for
AER?  Seems plausible to me.