Re: [PATCH 1/2] PCI/AER: Make aer_mask_override effective for injected errors

[sashiko-bot@kernel.org]

> The aer_mask_override module parameter of aer_inject is meant to allow
> injecting errors that the device masks in PCI_ERR_COR_MASK or
> PCI_ERR_UNCOR_MASK.  It does not work for Correctable or Non-Fatal
> errors, nor for Fatal errors on Root Ports and Downstream Ports,
> because the modified masks are restored before the AER driver reads
> them.
> 
> aer_inject() writes the modified masks to hardware and restores them
> from cor_mask_orig/uncor_mask_orig right after inject_lock is released,
> before irq_inject_interrupt() is even called.  The injected error is
> consumed asynchronously by the threaded handler aer_isr(), whose
> helpers is_error_source(), aer_get_device_error_info() and
> aer_get_anfe_status() read the Mask registers.  Those reads go through
> the emulated config space, but find_pci_config_dword() does not
> intercept PCI_ERR_COR_MASK/PCI_ERR_UNCOR_MASK, so they return the
> [ ... ]
> masked in PCI_ERR_UNCOR_MASK after aer_inject has been unloaded; with
> the read-side emulation alone it ended up unmasked.
> 
> Fixes: 457d9d088b02 ("PCI: aer-inject: Override PCIe AER Mask Registers")
> Signed-off-by: Priyank Rathod <rathodpriyank@google.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20261012-fix-aer-mask-override-v1-0-49a0d7aeaea0@google.com?part=1