[+cc Florian, sorry, I hadn't seen your ack when I sent the below]
On Tue, Nov 10, 2020 at 03:21:36PM -0600, Bjorn Helgaas wrote:
> [+cc Nicolas, Jingoo, Gustavo, Toan]
>
> On Sun, Nov 08, 2020 at 08:11:40PM +0100, Martin Kaiser wrote:
> > Replace the two separate calls for removing the irq handler and data with a
> > single irq_set_chained_handler_and_data() call.
>
> This is similar to these:
>
> 36f024ed8fc9 ("PCI/MSI: pci-xgene-msi: Consolidate chained IRQ handler install/remove")
> 5168a73ce32d ("PCI/keystone: Consolidate chained IRQ handler install/remove")
> 2cf5a03cb29d ("PCI/keystone: Fix race in installing chained IRQ handler")
>
> and it seems potentially important that this removes the IRQ handler
> and data *atomically*, i.e., both are done while holding
> irq_get_desc_buslock().
>
> So I would use this:
>
> PCI: altera-msi: Fix race in installing chained IRQ handler
>
> Fix a race where a pending interrupt could be received and the handler
> called before the handler's data has been setup by converting to
> irq_set_chained_handler_and_data().
>
> See also 2cf5a03cb29d ("PCI/keystone: Fix race in installing chained
> IRQ handler").
>
> to make it clear that this is actually a bug fix, not just a cleanup.
>
> Looks like this should also be done in dw_pcie_free_msi() and
> xgene_msi_hwirq_alloc() at the same time?
>
> > Signed-off-by: Martin Kaiser <martin@xxxxxxxxx>
> > ---
> > drivers/pci/controller/pcie-altera-msi.c | 3 +--
> > 1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/pci/controller/pcie-altera-msi.c b/drivers/pci/controller/pcie-altera-msi.c
> > index e1636f7714ca..42691dd8ebef 100644
> > --- a/drivers/pci/controller/pcie-altera-msi.c
> > +++ b/drivers/pci/controller/pcie-altera-msi.c
> > @@ -204,8 +204,7 @@ static int altera_msi_remove(struct platform_device *pdev)
> > struct altera_msi *msi = platform_get_drvdata(pdev);
> >
> > msi_writel(msi, 0, MSI_INTMASK);
> > - irq_set_chained_handler(msi->irq, NULL);
> > - irq_set_handler_data(msi->irq, NULL);
> > + irq_set_chained_handler_and_data(msi->irq, NULL, NULL);
> >
> > altera_free_domains(msi);
> >
> > --
> > 2.20.1
> >
