On Gen2 VMs, Hyper-V provides mmio space for framebuffer.
This mmio address range is not useable for other PCI devices.
Currently only efifb driver is using this range without reserving
it from system.
Therefore, vmbus driver reserves it before any other PCI device
drivers start to request mmio addresses.
PR: 222996
Submitted by: weh@microsoft.com
Reported by: dmitry_kuleshov@ukr.net
Reviewed by: decui@microsoft.com
Sponsored by: Microsoft
This change adds Hyper-V socket feature in FreeBSD. New socket address
family AF_HYPERV and its kernel support are added.
Submitted by: Wei Hu <weh@microsoft.com>
Reviewed by: Dexuan Cui <decui@microsoft.com>
Relnotes: yes
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D24061
Add VMBus protocol version 4.0. and 5.0 to support Windows 10 and newer HyperV hosts.
For VMBus 4.0 and newer HyperV, the netvsc gpadl teardown must be done after vmbus close.
Submitted by: whu
MFC after: 2 weeks
Sponsored by: Microsoft
The implementation of the Kernel Page Table Isolation (KPTI) for
amd64, first version. It provides a workaround for the 'meltdown'
vulnerability. PTI is turned off by default for now, enable with the
loader tunable vm.pmap.pti=1.
The pmap page table is split into kernel-mode table and user-mode
table. Kernel-mode table is identical to the non-PTI table, while
usermode table is obtained from kernel table by leaving userspace
mappings intact, but only leaving the following parts of the kernel
mapped:
kernel text (but not modules text)
PCPU
GDT/IDT/user LDT/task structures
IST stacks for NMI and doublefault handlers.
Kernel switches to user page table before returning to usermode, and
restores full kernel page table on the entry. Initial kernel-mode
stack for PTI trampoline is allocated in PCPU, it is only 16
qwords. Kernel entry trampoline switches page tables. then the
hardware trap frame is copied to the normal kstack, and execution
continues.
IST stacks are kept mapped and no trampoline is needed for
NMI/doublefault, but of course page table switch is performed.
On return to usermode, the trampoline is used again, iret frame is
copied to the trampoline stack, page tables are switched and iretq is
executed. The case of iretq faulting due to the invalid usermode
context is tricky, since the frame for fault is appended to the
trampoline frame. Besides copying the fault frame and original
(corrupted) frame to kstack, the fault frame must be patched to make
it look as if the fault occured on the kstack, see the comment in
doret_iret detection code in trap().
Currently kernel pages which are mapped during trampoline operation
are identical for all pmaps. They are registered using
pmap_pti_add_kva(). Besides initial registrations done during boot,
LDT and non-common TSS segments are registered if user requested their
use. In principle, they can be installed into kernel page table per
pmap with some work. Similarly, PCPU can be hidden from userspace
mapping using trampoline PCPU page, but again I do not see much
benefits besides complexity.
PDPE pages for the kernel half of the user page tables are
pre-allocated during boot because we need to know pml4 entries which
are copied to the top-level paging structure page, in advance on a new
pmap creation. I enforce this to avoid iterating over the all
existing pmaps if a new PDPE page is needed for PTI kernel mappings.
The iteration is a known problematic operation on i386.
The need to flush hidden kernel translations on the switch to user
mode make global tables (PG_G) meaningless and even harming, so PG_G
use is disabled for PTI case. Our existing use of PCID is
incompatible with PTI and is automatically disabled if PTI is
enabled. PCID can be forced on only for developer's benefit.
MCE is known to be broken, it requires IST stack to operate completely
correctly even for non-PTI case, and absolutely needs dedicated IST
stack because MCE delivery while trampoline did not switched from PTI
stack is fatal. The fix is pending.
Reviewed by: markj (partially)
Tested by: pho (previous version)
Discussed with: jeff, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Event tasks are pinned to their respective CPU by default, in the same
fashion as they were.
Unpin the event tasks by setting hw.vmbus.pin_evttask to 0, if certain
CPUs serve special purpose.
MFC after: 3 days
Sponsored by: Microsoft
For GEN1 Hyper-V, vmbus is attached to pcib0, which contains the
resources for PCI passthrough and SR-IOV. There is no
acpi_syscontainer0 on GEN1 Hyper-V.
For GEN2 Hyper-V, vmbus is attached to acpi_syscontainer0, which
contains the resources for PCI passthrough and SR-IOV. There is
no pcib0 on GEN2 Hyper-V.
The ACPI VMBUS device now only holds its _CRS, which is empty as
of this commit; its existence is mainly for upward compatibility.
Device tree structure is suggested by jhb@.
Tested-by: dexuan@
Collabrated-wth: dexuan@
MFC after: 1 week
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D10565
vmbus_pcib requires NEW_PCIB, but in case that's not defined, we at
least shouldn't break build.
Reviewed by: sephe
Approved by: sephe (mentor)
MFC after: 3 days
Sponsored by: Microsoft
We'd better add this dependency explicitly, though usually the pci
driver is built into the kernel by default.
Reviewed by: sephe
Approved by: sephe (mentor)
MFC after: 1 week
Sponsored by: Microsoft
The new methods will be used by the coming pcib driver.
Reviewed by: sephe
Approved by: sephe (mentor)
MFC after: 1 week
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8409
vcpu_id is host's representation of guest CPU.
We get the mapping between vcpu_id and FreeBSD kernel's cpu id when VMBus
driver is loaded. Later, when a driver, like the coming pcib driver, talks
to the host and needs to refer to a guest CPU, the driver must use the
vcpu_id.
Reviewed by: jhb, sephe
Approved by: sephe (mentor)
MFC after: 1 week
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8410
Just as most of other drivers do. And move sysinit function close
to its SYSINIT.
MFC after: 1 week
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D7347
It only contains bufring related bits for a while.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7281
Mainly for compatibility. While I'm here, rename cpuid related
fields in hv_vmbus_channel.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7141
Device detach method may sleep.
While I'm here, rename the function, fix indentation and function
comment.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7110
This paves way for the further cleanup/disentangle.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7092
This paves way to nuke the hv_device, which is actually an unncessary
indirection.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7032
This makes life easier during the transition period to nuke the hv_device.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7026
This prepares to remove the unnecessary offer message embedding in
hv_vmbus_channel.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D7020
Instead of global variable, vmbus version is accessed through
a vmbus DEVMETHOD now.
MFC after: 1 week
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D6953
