This is a note to let you know that I've just added the patch titled PCI/MSI: Fix incorrect MSI-X masking on resume to the 4.4-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-fix-incorrect-msi-x-masking-on-resume.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From e045fa29e89383c717e308609edd19d2fd29e1be Mon Sep 17 00:00:00 2001 From: Jian-Hong Pan <jian-hong@xxxxxxxxxxxx> Date: Tue, 8 Oct 2019 11:42:39 +0800 Subject: PCI/MSI: Fix incorrect MSI-X masking on resume From: Jian-Hong Pan <jian-hong@xxxxxxxxxxxx> commit e045fa29e89383c717e308609edd19d2fd29e1be upstream. When a driver enables MSI-X, msix_program_entries() reads the MSI-X Vector Control register for each vector and saves it in desc->masked. Each register is 32 bits and bit 0 is the actual Mask bit. When we restored these registers during resume, we previously set the Mask bit if *any* bit in desc->masked was set instead of when the Mask bit itself was set: pci_restore_state pci_restore_msi_state __pci_restore_msix_state for_each_pci_msi_entry msix_mask_irq(entry, entry->masked) <-- entire u32 word __pci_msix_desc_mask_irq(desc, flag) mask_bits = desc->masked & ~PCI_MSIX_ENTRY_CTRL_MASKBIT if (flag) <-- testing entire u32, not just bit 0 mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT writel(mask_bits, desc_addr + PCI_MSIX_ENTRY_VECTOR_CTRL) This means that after resume, MSI-X vectors were masked when they shouldn't be, which leads to timeouts like this: nvme nvme0: I/O 978 QID 3 timeout, completion polled On resume, set the Mask bit only when the saved Mask bit from suspend was set. This should remove the need for 19ea025e1d28 ("nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T"). [bhelgaas: commit log, move fix to __pci_msix_desc_mask_irq()] Link: https://bugzilla.kernel.org/show_bug.cgi?id=204887 Link: https://lore.kernel.org/r/20191008034238.2503-1-jian-hong@xxxxxxxxxxxx Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code") Signed-off-by: Jian-Hong Pan <jian-hong@xxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx 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 @@ -224,7 +224,7 @@ u32 __pci_msix_desc_mask_irq(struct msi_ return 0; mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; - if (flag) + if (flag & PCI_MSIX_ENTRY_CTRL_MASKBIT) mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT; writel(mask_bits, desc->mask_base + offset); Patches currently in stable-queue which might be from jian-hong@xxxxxxxxxxxx are queue-4.4/pci-msi-fix-incorrect-msi-x-masking-on-resume.patch