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pci: Fix the update of interrupt disable bit in PCI_COMMAND register
From: |
Guoyi Tu |
Subject: |
pci: Fix the update of interrupt disable bit in PCI_COMMAND register |
Date: |
Fri, 11 Aug 2023 22:46:51 +0800 |
User-agent: |
Mozilla Thunderbird |
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:
#0 pci_default_write_config (d=0x5580bbfc6230, addr=5, val_in=5, l=1)
at hw/pci/pci.c:1442
#1 0x00005580b8f3156a in virtio_write_config (pci_dev=0x5580bbfc6230,
address=5, val=5, len=1)
at hw/virtio/virtio-pci.c:605
#2 0x00005580b8ed2f3b in pci_host_config_write_common
(pci_dev=0x5580bbfc6230, addr=5, limit=256,
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>
---
hw/pci/pci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index b8d22e2e74..881d774fb6 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -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)
--
2.27.0
--
Guoyi
- pci: Fix the update of interrupt disable bit in PCI_COMMAND register,
Guoyi Tu <=