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pci: Fix the update of interrupt disable bit in PCI_COMMAND register

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The PCI_COMMAND register is located at offset 4 within
the PCI configuration space and occupies 2 bytes. The
interrupt disable bit is at the 10th bit, which corresponds
to the byte at offset 5 in the PCI configuration space.

In our testing environment, the guest driver may directly
updates the byte at offset 5 in the PCI configuration space.
The backtrace looks like as following:
    at hw/pci/pci.c:1442
    at hw/virtio/virtio-pci.c:605
    val=5, len=1) at hw/pci/pci_host.c:81

In this situation, the range_covers_byte function called
by the pci_default_write_config function will return false,
resulting in the inability to handle the interrupt disable
update event.

To fix this issue, we can use the ranges_overlap function
instead of range_covers_byte to determine whether the interrupt
bit has been updated.

Signed-off-by: Guoyi Tu <tugy@chinatelecom.cn>
Signed-off-by: yuanminghao <yuanmh12@chinatelecom.cn>
Message-Id: <ce2d0437-8faa-4d61-b536-4668f645a959@chinatelecom.cn>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes: b6981cb57b ("pci: interrupt disable bit support")
This commit is contained in:
Guoyi Tu 2023-08-11 22:46:51 +08:00 committed by Michael S. Tsirkin
parent 3d449bc603
commit 0f936247e8
1 changed files with 1 additions and 1 deletions
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2
hw/pci/pci.c
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@ -1613,7 +1613,7 @@ void pci_default_write_config(PCIDevice *d, uint32_t addr, uint32_t val_in, int
range_covers_byte(addr, l, PCI_COMMAND))
pci_update_mappings(d);
if (range_covers_byte(addr, l, PCI_COMMAND)) {
if (ranges_overlap(addr, l, PCI_COMMAND, 2)) {
pci_update_irq_disabled(d, was_irq_disabled);
memory_region_set_enabled(&d->bus_master_enable_region,
(pci_get_word(d->config + PCI_COMMAND)