On 13/11/2018 22:57, Marc Zyngier wrote: > It recently came to light that the Designware PCIe driver is rather > broken in the way it handles MSI[1]: > > - It masks interrupt by disabling them, meaning that MSIs generated > during the masked window are simply lost. Oops. > > - Acking of the currently pending MSI is done outside of the interrupt > flow, getting moved around randomly and ultimately breaking the > driver. Not great. > > This series attempts to address this by switching to using the MASK > register for masking interrupts (!), and move the ack into the > appropriate callback, giving it a fixed place in the MSI handling > flow. > > Note that this is only compile-tested on my arm64 laptop, as I'm > travelling and do not have the required HW to test it anyway. I'd > welcome both review and testing by the interested parties (dwc > maintainer and users affected by existing bugs). As we spoke on the conference, as soon as I get back and I've the necessary conditions I'll test the discussed modifications on my HW. > > Thanks, > > M. > > [1] https://urldefense.proofpoint.com/v2/url?u=https-3A__patchwork.kernel.org_patch_10657987_&d=DwIDAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=bkWxpLoW-f-E3EdiDCCa0_h0PicsViasSlvIpzZvPxs&m=ksl4uVn2tYUOeqywcyeYHziG6ejYHFeq-Cm4p8q7amU&s=WILOPbhOsYjM3XNhZwxGb2T6069LtLL1aqf9hbS-ajg&e= > > Marc Zyngier (3): > PCI: designware: Use interrupt masking instead of disabling > PCI: designware: Take lock when ACKing an interrupt > PCI: designware: Move interrupt acking into the proper callback > > .../pci/controller/dwc/pcie-designware-host.c | 22 ++++++++++++------- > 1 file changed, 14 insertions(+), 8 deletions(-) >
