[PATCH 5.15 119/177] PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error

Greg Kroah-Hartman
2021-12-20T15:14:12Z

From: Thomas Gleixner <tglx@linutronix.de>

commit 94185adbfad56815c2c8401e16d81bdb74a79201 upstream.

PCI_MSIX_FLAGS_MASKALL is set in the MSI-X control register at MSI-X
interrupt setup time. It's cleared on success, but the error handling path
only clears the PCI_MSIX_FLAGS_ENABLE bit.

That's incorrect as the reset state of the PCI_MSIX_FLAGS_MASKALL bit is
zero. That can be observed via lspci:

Capabilities: [b0] MSI-X: Enable- Count=67 Masked+

Clear the bit in the error path to restore the reset state.

Fixes: 438553958ba1 ("PCI/MSI: Enable and mask MSI-X early")
Reported-by: Stefan Roese <sr@denx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Stefan Roese <sr@denx.de>
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Marek Vasut <marex@denx.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87tufevoqx.ffs@tglx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/pci/msi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -776,7 +776,7 @@ out_free:
free_msi_irqs(dev);

out_disable:
- pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
+ pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE, 0);

return ret;
}