This is a note to let you know that I've just added the patch titled
PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-msi-clear-pci_msix_flags_maskall-on-error.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 94185adbfad56815c2c8401e16d81bdb74a79201 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Date: Tue, 14 Dec 2021 12:42:14 +0100
Subject: PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error
From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
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@xxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Tested-by: Stefan Roese <sr@xxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Michal Simek <michal.simek@xxxxxxxxxx>
Cc: Marek Vasut <marex@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/87tufevoqx.ffs@tglx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;
}
Patches currently in stable-queue which might be from tglx@xxxxxxxxxxxxx are
queue-5.15/pci-msi-mask-msi-x-vectors-only-on-success.patch
queue-5.15/locking-rtmutex-fix-incorrect-condition-in-rtmutex_spin_on_owner.patch
queue-5.15/timekeeping-really-make-sure-wall_to_monotonic-isn-t-positive.patch
queue-5.15/pci-msi-clear-pci_msix_flags_maskall-on-error.patch
