On 20.06.2024 11:40, Chen, Jiqian wrote: > On 2024/6/18 17:23, Jan Beulich wrote: >> On 18.06.2024 10:23, Chen, Jiqian wrote: >>> On 2024/6/17 23:32, Jan Beulich wrote: >>>> On 17.06.2024 11:00, Jiqian Chen wrote: >>>>> @@ -1516,14 +1519,39 @@ static void pci_add_dm_done(libxl__egc *egc, >>>>> rc = ERROR_FAIL; >>>>> goto out; >>>>> } >>>>> - r = xc_domain_irq_permission(ctx->xch, domid, irq, 1); >>>>> +#ifdef CONFIG_X86 >>>>> + /* If dom0 doesn't have PIRQs, need to use >>>>> xc_domain_gsi_permission */ >>>>> + r = xc_domain_getinfo_single(ctx->xch, 0, &info); >>>> >>>> Hard-coded 0 is imposing limitations. Ideally you would use DOMID_SELF, but >>>> I didn't check if that can be used with the underlying hypercall(s). >>>> Otherwise > From the commit 10ef7a91b5a8cb8c58903c60e2dd16ed490b3bcf, DOMID_SELF is not > allowed for XEN_DOMCTL_getdomaininfo. > And now XEN_DOMCTL_getdomaininfo gets domain through rcu_lock_domain_by_id. > >>>> you want to pass the actual domid of the local domain here. > What is the local domain here?
The domain your code is running in. > What is method for me to get its domid? I hope there's an available function in one of the libraries to do that. But I wouldn't even know what to look for; that's a question to (primarily) Anthony then, who sadly continues to be our only tool stack maintainer. Alternatively we could maybe enable XEN_DOMCTL_getdomaininfo to permit DOMID_SELF. >>> But the action of granting permission is from dom0 to domU, what I need to >>> get is the infomation of dom0, >>> The actual domid here is domU's id I think, it is not useful. >> >> Note how I said DOMID_SELF and "local domain". There's no talk of using the >> DomU's domid. But what you apparently neglect is the fact that the hardware >> domain isn't necessarily Dom0 (see CONFIG_LATE_HWDOM in the hypervisor). >> While benign in most cases, this is relevant when it comes to referencing >> the hardware domain by domid. And it is the hardware domain which is going >> to drive the device re-assignment, as that domain is who's in possession of >> all the devices not yet assigned to any DomU. > OK, I need to get the information of hardware domain here? Right, with (for this purpose) "hardware domain" == "local domain". Jan
