On Tue, Nov 13, 2018 at 10:57:31PM +0000, 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). > > Thanks, > > M. > > [1] https://patchwork.kernel.org/patch/10657987/ > > 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(-) Applied to pci/dwc-msi for v4.21 with tags and minor log updates. All, please have a look and possibly keep testing it, I will ask Bjorn to move it into -next shortly. Thanks, Lorenzo