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