Blame SOURCES/kvm-vfio-pci-do-not-set-the-PCIDevice-has_rom-attribute.patch

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From 3483f36dbf965a4ca01c4a2d3bce1132340596d1 Mon Sep 17 00:00:00 2001
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From: "plai@redhat.com" <plai@redhat.com>
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Date: Fri, 31 Aug 2018 16:25:52 +0200
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Subject: [PATCH 10/29] vfio/pci: do not set the PCIDevice 'has_rom' attribute
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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RH-Author: plai@redhat.com
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Message-id: <1535732759-22481-3-git-send-email-plai@redhat.com>
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Patchwork-id: 82004
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O-Subject: [RHEL7.6 PATCH BZ 1539280 2/9] vfio/pci: do not set the PCIDevice 'has_rom' attribute
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Bugzilla: 1539280
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RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>
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RH-Acked-by: Pankaj Gupta <pagupta@redhat.com>
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RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
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From: Cédric Le Goater <clg@kaod.org>
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PCI devices needing a ROM allocate an optional MemoryRegion with
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pci_add_option_rom(). pci_del_option_rom() does the cleanup when the
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device is destroyed. The only action taken by this routine is to call
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vmstate_unregister_ram() which clears the id string of the optional
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ROM RAMBlock and now, also flags the RAMBlock as non-migratable. This
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was recently added by commit b895de502717 ("migration: discard
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non-migratable RAMBlocks"), .
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VFIO devices do their own loading of the PCI option ROM in
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vfio_pci_size_rom(). The memory region is switched to an I/O region
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and the PCI attribute 'has_rom' is set but the RAMBlock of the ROM
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region is not allocated. When the associated PCI device is deleted,
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pci_del_option_rom() calls vmstate_unregister_ram() which tries to
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flag a NULL RAMBlock, leading to a SEGV.
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It seems that 'has_rom' was set to have memory_region_destroy()
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called, but since commit 469b046ead06 ("memory: remove
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memory_region_destroy") this is not necessary anymore as the
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MemoryRegion is freed automagically.
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Remove the PCIDevice 'has_rom' attribute setting in vfio.
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Fixes: b895de502717 ("migration: discard non-migratable RAMBlocks")
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Signed-off-by: Cédric Le Goater <clg@kaod.org>
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Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
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Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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(cherry picked from commit 26c0ae56386edacc8b0da40264748f59afedb1bb)
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Signed-off-by: Paul Lai <plai@redhat.com>
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 hw/vfio/pci.c | 1 -
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 1 file changed, 1 deletion(-)
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diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
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index 4683eb4..c00b91c 100644
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--- a/hw/vfio/pci.c
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+++ b/hw/vfio/pci.c
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@@ -990,7 +990,6 @@ static void vfio_pci_size_rom(VFIOPCIDevice *vdev)
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     pci_register_bar(&vdev->pdev, PCI_ROM_SLOT,
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                      PCI_BASE_ADDRESS_SPACE_MEMORY, &vdev->pdev.rom);
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-    vdev->pdev.has_rom = true;
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     vdev->rom_read_failed = false;
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 }
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-- 
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1.8.3.1
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