Re: Instability in ALL stable and LTS distro kernels (IRQ #16 being disabled, PCIe bus errors, ath10k_pci) in Dell Inspiron 5567

[Bjorn Helgaas <helgaas@kernel.org>]

On Sat, Jul 05, 2025 at 01:00:23AM +0530, Bandhan Pramanik wrote:
> Hi everyone,
> 
> Here after a week. I did my research.
> 
> I talked to some folks on IRC and the glaring issue was basically this: 
> 
> > [ 1146.810055] pcieport 0000:00:1c.0: AER: Uncorrectable (Fatal) error message received from 0000:01:00.0

Where is the complete dmesg log from which this is extracted?

> This basically means that the root port (that 1c thing written with
> colons) of PCIe is the main problem here. 
> 
> One particular note: this issue can be reproduced on the models of
> this same laptop. Therefore, this happens in most if not all of the
> laptops of the same model.
> 
> For starters, the root port basically manages the communication
> between the CPU and the device. Now, this root port itself is
> reporting fatal errors.
> 
> This is not a Wi-Fi error, but something deeper. 

Devices that support AER have extra log registers to capture details
about an error.  A device that detects an error sends a PCIe Error
Message upstream to a Root Port.  The Root Port generates an
interrupt, which is handled by the aer driver.  In this case, the
01:00.0 device detected an error and sent an ERR_FATAL message
upstream, and the 00:1c.0 Root Port received it and generated an
interrupt.  The ERR_FATAL message doesn't contain any details about
the error itself, so the aer driver looks for the AER registers in the
01:00.0 device and logs those details to the dmesg log.  Normally
there would be a few lines after the one you quoted that would include
those details.

Bjorn