PCI/MSI: Decouple MSI[-X] disable from pcim_release()

The MSI core will introduce runtime allocation of MSI related data. This
data will be devres managed and has to be set up before enabling
PCI/MSI[-X]. This would introduce an ordering issue vs. pcim_release().

The setup order is:

   pcim_enable_device()
	devres_alloc(pcim_release...);
	...
	pci_irq_alloc()
	  msi_setup_device_data()
	     devres_alloc(msi_device_data_release, ...)

and once the device is released these release functions are invoked in the
opposite order:

    msi_device_data_release()
    ...
    pcim_release()
       pci_disable_msi[x]()

which is obviously wrong, because pci_disable_msi[x]() requires the MSI
data to be available to tear down the MSI[-X] interrupts.

Remove the MSI[-X] teardown from pcim_release() and add an explicit action
to be installed on the attempt of enabling PCI/MSI[-X].

This allows the MSI core data allocation to be ordered correctly in a
subsequent step.

Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/87tuf9rdoj.ffs@tglx

1 files changed, 2 insertions, 1 deletions

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 5cc46baef519..a09736d3e05e 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -425,7 +425,8 @@ struct pci_dev {
 	unsigned int	ats_enabled:1;		/* Address Translation Svc */
 	unsigned int	pasid_enabled:1;	/* Process Address Space ID */
 	unsigned int	pri_enabled:1;		/* Page Request Interface */
-	unsigned int	is_managed:1;
+	unsigned int	is_managed:1;		/* Managed via devres */
+	unsigned int	is_msi_managed:1;	/* MSI release via devres installed */
 	unsigned int	needs_freset:1;		/* Requires fundamental reset */
 	unsigned int	state_saved:1;
 	unsigned int	is_physfn:1;