Re: [PATCH v5 03/18] PCI: Propagate FLR return values to callers

[Nicolin Chen <nicolinc@nvidia.com>]

On Thu, Aug 27, 2026 at 05:31:31PM -0300, Jason Gunthorpe wrote:
> > [ ... 24 lines skipped ... ]
> > Since these quirks have always returned success, escalating
> > would be a new and harmful behavior: the next method is typically the plain
> > "flr" method, which would re-run the same FLR without the extra steps the
> > quirk wraps around its pcie_flr() call. Add quirk_flr_err() converting that
> > -ENOTTY to -ETIMEDOUT, so the cascade still stops at the quirk as before.
> > The early "not applicable" -ENOTTY returns are left intact, and they still
> > ask the caller to try the next method.
> 
> This seems like a very suspect AI conclusion to me.
> 
> I think I'd drop this patch
> 
> > Convert it at the quirk level rather than in pcie_flr() or pci_dev_wait(),
> > because those also serve the native "flr"/"af_flr"/"pm" methods, where the
> > -ENOTTY on timeout is deliberate per commit 91295d79d658 ("PCI: Handle FLR
> > failure and allow other reset types"): a timed-out native FLR escalates to
> > a stronger reset (e.g. bus reset), which skips no workaround there and may
> > recover the device. Converting in the core would also change the value seen
> > by every direct pcie_flr() caller.
> > 
> > This is not a bug fix, since these functions have always returned success
> > and the propagated values are only consumed by incoming work.
> 
> In what way? The quirks flows always succeed and it can keep always
> succeeding. If anyone finds this problematic they can properly
> propogate the error.
> 
> Squashing the error just for quirks makes little sense.

PATCH-5 forwards the return values to pci_dev_reset_iommu_done(),
so IOMMU can keep a device blocked on a nonzero result. Dropping
this patch would leave the three VF quirks here always reporting
success, reopening the stale-ATC issue this series is fixing for
them.

Or do you think it's okay?

Thanks
Nicolin