Re: [PATCH 4.4 009/134] PCI/MSI: Stop disabling MSI/MSI-X in pci_device_shutdown()

[Ben Hutchings]

On Mon, 2018-03-19 at 19:04 +0100, Greg Kroah-Hartman wrote:
> 4.4-stable review patch.ÂÂIf anyone has any objections, please let me know.
> 
> ------------------
> 
> From: Prarit Bhargava <prarit@xxxxxxxxxx>
> 
> 
> [ Upstream commit fda78d7a0ead144f4b2cdb582dcba47911f4952c ]
[...]
> The MSI disabling code was added by d52877c7b1af ("pci/irq: let
> pci_device_shutdown to call pci_msi_shutdown v2") because a driver left MSI
> enabled and kdump failed because the kexeced kernel wasn't prepared to
> receive the MSI interrupts.
> 
> Subsequent commits 1851617cd2da ("PCI/MSI: Disable MSI at enumeration even
> if kernel doesn't support MSI")

This went into 4.2 and hasn't been backported.

> andÂÂe80e7edc55ba ("PCI/MSI: Initialize MSI capability for all
> architectures")

This went into 4.5 and hasn't been backported.

> changed the kexeced kernel to disable all MSIs itself so it no longer
> depends on the crashed kernel to clean upÂafter itself.
[...]

So I think 3.18-stable and 4.4-stable will need backports of the later
changes in order for this to work properly.

Ben.

-- 
Ben Hutchings
Software Developer, Codethink Ltd.