On 2014-07-01 15:02, Le Tan wrote: > 2014-07-01 20:56 GMT+08:00 Jan Kiszka <jan.kis...@web.de>: >> On 2014-07-01 14:55, Le Tan wrote: >>> 2014-07-01 20:52 GMT+08:00 Le Tan <tamlokv...@gmail.com>: >>>> Hi Jan, >>>> >>>> 2014-07-01 15:34 GMT+08:00 Jan Kiszka <jan.kis...@web.de>: >>>>> Hi Le, >>>>> >>>>> On 2014-07-01 04:34, Le Tan wrote: >>>>>> Hi Jan, >>>>>> I use pci_setup_iommu() to setup a PCIIOMMUFunc for the q35 pci bus. >>>>>> In the iommu_fn, I print out the devfn parameter and find out that it >>>>>> sometimes will be -1. So what does it mean? >>>>>> The detail code is here: >>>>>> >>>>>> In mch_init() function, I write like this: >>>>>> PCIBus *pci_bus = PCI_BUS(qdev_get_parent_bus(DEVICE(mch))); >>>>>> pci_setup_iommu(pci_bus, q35_host_dma_iommu, mch->iommu); >>>>>> >>>>>> And in q35_host_dma_iommu(PCIBus *bus, void *opaque, int devfn), I >>>>>> print out the devfn parameter, sometimes it will be -1. >>>>> >>>>> Hmm, I have no idea about the reason and would suggest to set a >>>>> conditional breakpoint on this function, then print the backtrace to see >>>>> where this comes from and analyze the device structure from where that >>>>> -1 was most probably taken. >>> >>> I think maybe this is a bug? In the function do_pci_register_device(), >>> maybe these two sentence should be reorder? >>> dma_as = pci_device_iommu_address_space(pci_dev); >>> pci_dev->devfn = devfn; >> >> Looks like. Give it a try, then possibly send a patch :) > I reorder these two sentences and get the print log like this: > vtd bus 0 slot 31 func 0 devfn 248 > vtd bus 0 slot 31 func 2 devfn 250 > vtd bus 0 slot 31 func 3 devfn 251 > vtd bus 0 slot 1 func 0 devfn 8 > vtd bus 0 slot 2 func 0 devfn 16 > > The "info pci" output is here: > (qemu) info pci > Bus 0, device 0, function 0: > Host bridge: PCI device 8086:29c0 > id "" > Bus 0, device 1, function 0: > VGA controller: PCI device 1013:00b8 > BAR0: 32 bit prefetchable memory at 0xfc000000 [0xfdffffff]. > BAR1: 32 bit memory at 0xfebf0000 [0xfebf0fff]. > BAR6: 32 bit memory at 0xffffffffffffffff [0x0000fffe]. > id "" > Bus 0, device 2, function 0: > Ethernet controller: PCI device 8086:100e > IRQ 11. > BAR0: 32 bit memory at 0xfebc0000 [0xfebdffff]. > BAR1: I/O at 0xc000 [0xc03f]. > BAR6: 32 bit memory at 0xffffffffffffffff [0x0003fffe]. > id "" > Bus 0, device 31, function 0: > ISA bridge: PCI device 8086:2918 > id "" > Bus 0, device 31, function 2: > SATA controller: PCI device 8086:2922 > IRQ 10. > BAR4: I/O at 0xc080 [0xc09f]. > BAR5: 32 bit memory at 0xfebf1000 [0xfebf1fff]. > id "" > Bus 0, device 31, function 3: > SMBus: PCI device 8086:2930 > IRQ 10. > BAR4: I/O at 0x0700 [0x073f]. > id "" > > So maybe it is all right now? And I will go on the vtd emulation.:) > Thanks very much!
Looks better :). Don't forget to send the patch against pci.c! Jan
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