[patch V2 00/19] PCI/MSI, x86: Cure a couple of inconsistencies

From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Alex Williamson <alex.williamson@redhat.com>,
	"Raj, Ashok" <ashok.raj@intel.com>,
	"David S. Miller" <davem@davemloft.net>,
	Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci@vger.kernel.org, Kevin Tian <kevin.tian@intel.com>,
	Marc Zyngier <maz@kernel.org>, Ingo Molnar <mingo@kernel.org>,
	x86@kernel.org, linux-s390@vger.kernel.org,
	Niklas Schnelle <schnelle@linux.ibm.com>,
	Gerald Schaefer <gerald.schaefer@linux.ibm.com>,
	Heiko Carstens <hca@linux.ibm.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>
Subject: [patch V2 00/19] PCI/MSI, x86: Cure a couple of inconsistencies
Date: Thu, 29 Jul 2021 23:51:39 +0200	[thread overview]
Message-ID: <20210729215139.889204656@linutronix.de> (raw)

A recent discussion about the PCI/MSI management for virtio unearthed a
violation of the MSI-X specification vs. writing the MSI-X message: under
certain circumstances the entry is written without being masked.

While looking at that and the related violation of the x86 non-remapped
interrupt affinity mechanism a few other issues were discovered by
inspection.

The following series addresses these.

Note this does not fix the virtio issue, but while staring at the above
problems I came up with a plan to address this. I'm still trying to
convince myself that I can get away without sprinkling locking all over the
place, so don't hold your breath that this will materialize tomorrow.

The series is also available from git:

    git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git irq/msi

V1 can be found here:

   https://lore.kernel.org/r/20210721191126.274946280@linutronix.de

Changes vs. V1:

  - Identified and addressed more inconsistencies, especially the lack of
    serialization for multi-MSI masking

  - Removed the extra vector masking in S390 

  - Addressed review comments and picked up tags where applicable

  - Clean up of the naming of msi_desc::masked as discussed in the V1
    thread

  - Consolidation of the mask/unmask functions

Thanks,

	tglx
---
 arch/s390/pci/pci_irq.c        |    4 
 arch/x86/kernel/apic/io_apic.c |    6 
 arch/x86/kernel/apic/msi.c     |   11 +
 arch/x86/kernel/hpet.c         |    2 
 drivers/base/core.c            |    1 
 drivers/pci/msi.c              |  274 ++++++++++++++++++++++-------------------
 include/linux/device.h         |    1 
 include/linux/irq.h            |    2 
 include/linux/msi.h            |   10 -
 kernel/irq/chip.c              |    5 
 10 files changed, 178 insertions(+), 138 deletions(-)