The following commit has been merged into the irq/urgent branch of tip: Commit-ID: 83dbf898a2d45289be875deb580e93050ba67529 Gitweb: https://git.kernel.org/tip/83dbf898a2d45289be875deb580e93050ba67529 Author: Stefan Roese <sr@xxxxxxx> AuthorDate: Tue, 14 Dec 2021 12:49:32 +01:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Tue, 14 Dec 2021 13:23:32 +01:00 PCI/MSI: Mask MSI-X vectors only on success Masking all unused MSI-X entries is done to ensure that a crash kernel starts from a clean slate, which correponds to the reset state of the device as defined in the PCI-E specificion 3.0 and later: Vector Control for MSI-X Table Entries -------------------------------------- "00: Mask bit: When this bit is set, the function is prohibited from sending a message using this MSI-X Table entry. ... This bit’s state after reset is 1 (entry is masked)." A Marvell NVME device fails to deliver MSI interrupts after trying to enable MSI-X interrupts due to that masking. It seems to take the MSI-X mask bits into account even when MSI-X is disabled. While not specification compliant, this can be cured by moving the masking into the success path, so that the MSI-X table entries stay in device reset state when the MSI-X setup fails. [ tglx: Move it into the success path, add comment and amend changelog ] Fixes: aa8092c1d1f1 ("PCI/MSI: Mask all unused MSI-X entries") Signed-off-by: Stefan Roese <sr@xxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> 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/20211210161025.3287927-1-sr@xxxxxxx --- drivers/pci/msi.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 48e3f4e..6748cf9 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -722,9 +722,6 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, goto out_disable; } - /* Ensure that all table entries are masked. */ - msix_mask_all(base, tsize); - ret = msix_setup_entries(dev, base, entries, nvec, affd); if (ret) goto out_disable; @@ -751,6 +748,16 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, /* Set MSI-X enabled bits and unmask the function */ pci_intx_for_msi(dev, 0); dev->msix_enabled = 1; + + /* + * Ensure that all table entries are masked to prevent + * stale entries from firing in a crash kernel. + * + * Done late to deal with a broken Marvell NVME device + * which takes the MSI-X mask bits into account even + * when MSI-X is disabled, which prevents MSI delivery. + */ + msix_mask_all(base, tsize); pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0); pcibios_free_irq(dev);
