David Woodhouse [Mon, 23 Jan 2023 15:33:08 +0000 (16:33 +0100)]
Fix BE watch firing
We can't do this recursively from *within* the node walk. The callers
don't expect that, and we end up calling them with an invalid tree —
we glibly declared "we hold the lock so we can steal children from the
tree while we go down it, and nobody can notice", and that becomes untrue
if we then call *back* into the backends which then call into the XS code
again while it's in that state.
Defer the watch firing until the main loop goes idle again, which is how
it would happen for real Xen watches (which trigger via a pollable file
descriptor in the main loop).
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Sun, 22 Jan 2023 22:59:49 +0000 (22:59 +0000)]
hw/xen: Watches on XenStore transactions
Firing watches on the nodes that still exist is relatively easy; just
walk the tree and look at the nodes with refcount of one.
Firing watches on *deleted* nodes is more fun. We add 'modified_in_tx'
and 'deleted_in_tx' flags to each node. Nodes with those flags cannot
be shared, as they will always be unique to the transaction in which
they were created.
When xs_node_walk would need to *create* a node as scaffolding and it
encounters a deleted_in_tx node, it can resurrect it simply by clearing
its deleted_in_tx flag. If that node originally had any *data*, they're
gone, and the modified_in_tx flag will have been set when it was first
deleted.
We then attempt to send appropriate watches when the transaction is
committed, properly delete the deleted_in_tx nodes, and remove the
modified_in_tx flag from the others.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Sun, 22 Jan 2023 22:05:37 +0000 (22:05 +0000)]
hw/xen: Implement XenStore transactions
Given that the whole thing supported copy on write from the beginning,
transactions end up being fairly simple. On starting a transaction, just
take a ref of the existing root; swap it back in on a successful commit.
The main tree has a transaction ID too, and we keep a record of the last
transaction ID given out. if the main tree is ever modified when it isn't
the latest, it gets a new transaction ID.
A commit can only succeed if the main tree hasn't moved on since it was
forked. Strictly speaking, the XenStore protocol allows a transaction to
succeed as long as nothing *it* read or wrote has changed in the interim,
but no implementations do that; *any* change is sufficient to abort a
transaction.
This does not yet fire watches on the changed nodes on a commit. That bit
is more fun and will come in a follow-on commit.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Sun, 22 Jan 2023 18:38:23 +0000 (18:38 +0000)]
hw/xen: Implement XenStore watches
Starts out fairly simple: a hash table of watches based on the path.
Except there can be multiple watches on the same path, so the watch ends
up being a simple linked list, and the head of that list is in the hash
table. Which makes removal a bit of a PITA but it's not so bad; we just
special-case "I had to remove the head of the list and now I have to
replace it in / remove it from the hash table". And if we don't remove
the head, it's a simple linked-list operation.
We do need to fire watches on *deleted* nodes, so instead of just a simple
xs_node_unref() on the topmost victim, we need to recurse down and fire
watches on them all.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Fri, 20 Jan 2023 01:36:38 +0000 (01:36 +0000)]
hw/xen: Add basic XenStore tree walk and write/read/directory support
This is a fairly simple implementation of a copy-on-write tree.
The node walk function starts off at the root, with 'inplace == true'.
If it ever encounters a node with a refcount greater than one (including
the root node), then that node is shared with other trees, and cannot
be modified in place, so the inplace flag is cleared and we copy on
write from there on down.
Xenstore write has 'mkdir -p' semantics and will create the intermediate
nodes if they don't already exist, so in that case we flip the inplace
flag back to true as as populated the newly-created nodes.
We put a copy of the absolute path into the buffer in the struct walk_op,
with *two* NUL terminators at the end. As xs_node_walk() goes down the
tree, it replaces the next '/' separator with a NUL so that it can use
the 'child name' in place. The next recursion down then puts the '/'
back and repeats the exercise for the next path element... if it doesn't
hit that *second* NUL termination which indicates the true end of the
path.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Thu, 19 Jan 2023 00:04:31 +0000 (00:04 +0000)]
hw/xen: Add stubs for XenStore backend implementation
We can actually initiaize xenbus now too; it's unhappy that everything
(except xs_open) fails, but at least it doesn't abort. OTOH, we *might*
not want to just yet, since we might start to see other failure modes
when we exercise my completely untested grant table code and other
stuff :)
We can probably implement serialize/deserialize by letting me worry about
that in the xen_xenstore.c side and just calling an impl function to
populate or consume a GByteArray. It can hand you the list of pending
(already fired, not yet delivered) watch events too, or append them after.
You can probably ditch the -kernel and -append if your disk image is set
up for serial bootloader and console. Or if you want to drop -display none
and actually deal with windows popping up :)
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Wed, 18 Jan 2023 18:55:47 +0000 (18:55 +0000)]
hw/xen: Add xenstore wire implementation and implementation stubs
This implements the basic wire protocol for the XenStore commands, punting
all the actual implementation to xs_impl_* functions which all just return
errors for now.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Tue, 10 Jan 2023 08:01:47 +0000 (08:01 +0000)]
i386/xen: Initialize XenBus and legacy backends from pc_init1()
Now that we're close to being able to use the PV backends without actual
Xen, move the bus instantiation out from xen_hvm_init_pc() to pc_init1().
However, still only do it for (xen_mode == XEN_ATTACH) (i.e. when running
on true Xen) because we don't have XenStore ops for emulation yet, and
the XenBus instantiation failure is fatal. Once we have a functional
XenStore for emulated mode, this will become (xen_mode != XEN_DISABLED).
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Tue, 10 Jan 2023 01:35:33 +0000 (01:35 +0000)]
hw/xen: Remove old version of Xen headers
For Xen emulation support, a full set of Xen headers was imported to
include/standard-headers/xen. This renders the original partial set in
include/hw/xen/interface redundant.
Now that the header ordering and handling of __XEN_INTERFACE_VERSION__
vs. __XEN_TOOLS__ is all untangled, remove the old set of headers and
use only the new ones.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Tue, 10 Jan 2023 01:09:04 +0000 (01:09 +0000)]
hw/xen: Implement soft reset for emulated gnttab
This is only part of it; we will also need to get the PV back end drivers
to tear down their own mappings (or do it for them, but they kind of need
to stop using the pointers too).
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Fri, 6 Jan 2023 09:59:28 +0000 (09:59 +0000)]
hw/xen: Add backend implementation of grant table operations
This is limited to mapping a single grant at a time, because under Xen the
pages are mapped *contiguously* into qemu's address space, and that's very
hard to do when those pages actually come from anonymous mappings in qemu
in the first place.
Eventually perhaps we can look at using shared mappings of actual objects
for system RAM, and then we can make new mappings of the same backing
store (be it deleted files, shmem, whatever). But for now let's stuck to
a page at a time.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Mon, 2 Jan 2023 00:39:13 +0000 (00:39 +0000)]
hw/xen: Rename xen_common.h to xen_native.h
This header is now only for native Xen code, not PV backends that may be
used in Xen emulation. Since the toolstack libraries may depend on the
specific version of Xen headers that they pull in (and will set the
__XEN_TOOLS__ macro to enable internal definitions that they depend on),
the rule is that xen_native.h (and thus the toolstack library headers)
must be included *before* any of the headers in standard-headers/xen.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Sat, 7 Jan 2023 16:47:43 +0000 (16:47 +0000)]
hw/xen: Use XEN_PAGE_SIZE in PV backend drivers
XC_PAGE_SIZE comes from the actual Xen libraries, while XEN_PAGE_SIZE is
provided by QEMU itself in xen_backend_ops.h. For backends which may be
built for emulation mode, use the latter.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Sat, 7 Jan 2023 16:17:51 +0000 (16:17 +0000)]
hw/xen: Move xenstore_store_pv_console_info to xen_console.c
There's no need for this to be in the Xen accel code, and as we want to
use the Xen console support with KVM-emulated Xen we'll want to have a
platform-agnostic version of it. Make it use GString to build up the
path while we're at it.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Sun, 1 Jan 2023 21:31:37 +0000 (21:31 +0000)]
hw/xen: Add gnttab operations to allow redirection to internal emulation
In emulation, mapping more than one grant ref to be virtually contiguous
would be fairly difficult. The best way to do it might be to make the
ram_block mappings actually backed by a file (shmem or a deleted file,
perhaps) so that we can have multiple *shared* mappings of it. But that
would be fairly intrusive.
Making the backend drivers cope with page *lists* instead of expecting
the mapping to be contiguous is also non-trivial, since some structures
would actually *cross* page boundaries (e.g. the 32-bit blkif responses
which are 12 bytes).
So for now, we'll support only single-page mappings in emulation.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Paul Durrant <pdurrant@amazon.com>
David Woodhouse [Fri, 13 Jan 2023 23:35:46 +0000 (23:35 +0000)]
hw/xen: Support MSI mapping to PIRQ
The way that Xen handles MSI PIRQs is kind of awful.
There is a special MSI message which targets a PIRQ. The vector in the
low bits of data must be zero. The low 8 bits of the PIRQ# are in the
destination ID field, the extended destination ID field is unused, and
instead the high bits of the PIRQ# are in the high 32 bits of the address.
Using the high bits of the address means that we can't intercept and
translate these messages in kvm_send_msi(), because they won't be caught
by the APIC — addresses like 0x1000fee46000 aren't in the APIC's range.
So we catch them in pci_msi_trigger() instead, and deliver the event
channel directly.
That isn't even the worst part. The worst part is that Xen snoops on
writes to devices' MSI vectors while they are *masked*. When a MSI
message is written which looks like it targets a PIRQ, it remembers
the device and vector for later.
When the guest makes a hypercall to bind that PIRQ# (snooped from a
marked MSI vector) to an event channel port, Xen *unmasks* that MSI
vector on the device. Xen guests using PIRQ delivery of MSI don't
ever actually unmask the MSI for themselves.
Now that this is working we can finally enable XENFEAT_hvm_pirqs and
let the guest use it all.
Tested with passthrough igb and emulated e1000e + AHCI.
David Woodhouse [Tue, 17 Jan 2023 13:51:22 +0000 (13:51 +0000)]
hw/xen: Automatically add xen-platform PCI device for emulated Xen guests
It isn't strictly mandatory but Linux guests at least will only map their
grant tables over the dummy BAR that it provides, and don't sufficient wit
to map them in any other unused part of their guest address space. So
include it by default for minimal surprise factor.
As I come to document "how to run a Xen guest in QEMU", this means one
fewer thing to tell the user about, according to the mantra of "if it
needs documenting, fix it first, then document what remains".
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Wed, 28 Dec 2022 10:06:49 +0000 (10:06 +0000)]
hw/xen: Add basic ring handling to xenstore
Extract requests, return ENOSYS to all of them. This is enough to allow
older Linux guests to boot, as they need *something* back but it doesn't
matter much what.
In the first instance we're likely to wire this up over a UNIX socket to
an actual xenstored implementation, but in the fullness of time it would
be nice to have a fully single-tenant "virtual" xenstore within qemu.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Tue, 27 Dec 2022 21:20:07 +0000 (21:20 +0000)]
hw/xen: Add backend implementation of interdomain event channel support
The provides the QEMU side of interdomain event channels, allowing events
to be sent to/from the guest.
The API mirrors libxenevtchn, and in time both this and the real Xen one
will be available through ops structures so that the PV backend drivers
can use the correct one as appropriate.
For now, this implementation can be used directly by our XenStore which
will be for emulated mode only.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Which is used to fetch xenstore PFN and port to be used
by the guest. This is preallocated by the toolstack when
guest will just read those and use it straight away.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Introduce support for one shot and periodic mode of Xen PV timers,
whereby timer interrupts come through a special virq event channel
with deadlines being set through:
David Woodhouse [Fri, 16 Dec 2022 00:03:21 +0000 (00:03 +0000)]
hw/xen: Support HVM_PARAM_CALLBACK_TYPE_PCI_INTX callback
The guest is permitted to specify an arbitrary domain/bus/device/function
and INTX pin from which the callback IRQ shall appear to have come.
In QEMU we can only easily do this for devices that actually exist, and
even that requires us "knowing" that it's a PCMachine in order to find
the PCI root bus — although that's OK really because it's always true.
We also don't get to get notified of INTX routing changes, because we
can't do that as a passive observer; if we try to register a notifier
it will overwrite any existing notifier callback on the device.
But in practice, guests using PCI_INTX will only ever use pin A on the
Xen platform device, and won't swizzle the INTX routing after they set
it up. So this is just fine.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Thu, 15 Dec 2022 20:35:24 +0000 (20:35 +0000)]
hw/xen: Support HVM_PARAM_CALLBACK_TYPE_GSI callback
The GSI callback (and later PCI_INTX) is a level triggered interrupt. It
is asserted when an event channel is delivered to vCPU0, and is supposed
to be cleared when the vcpu_info->evtchn_upcall_pending field for vCPU0
is cleared again.
Thankfully, Xen does *not* assert the GSI if the guest sets its own
evtchn_upcall_pending field; we only need to assert the GSI when we
have delivered an event for ourselves. So that's the easy part, kind of.
There's a slight complexity in that we need to hold the BQL before we
can call qemu_set_irq(), and we definitely can't do that while holding
our own port_lock (because we'll need to take that from the qemu-side
functions that the PV backend drivers will call). So if we end up
wanting to set the IRQ in a context where we *don't* already hold the
BQL, defer to a BH.
However, we *do* need to poll for the evtchn_upcall_pending flag being
cleared. In an ideal world we would poll that when the EOI happens on
the PIC/IOAPIC. That's how it works in the kernel with the VFIO eventfd
pairs — one is used to trigger the interrupt, and the other works in the
other direction to 'resample' on EOI, and trigger the first eventfd
again if the line is still active.
However, QEMU doesn't seem to do that. Even VFIO level interrupts seem
to be supported by temporarily unmapping the device's BARs from the
guest when an interrupt happens, then trapping *all* MMIO to the device
and sending the 'resample' event on *every* MMIO access until the IRQ
is cleared! Maybe in future we'll plumb the 'resample' concept through
QEMU's irq framework but for now we'll do what Xen itself does: just
check the flag on every vmexit if the upcall GSI is known to be
asserted.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Joao Martins [Tue, 21 Aug 2018 16:16:19 +0000 (12:16 -0400)]
i386/xen: add monitor commands to test event injection
Specifically add listing, injection of event channels.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
David Woodhouse [Tue, 13 Dec 2022 22:40:56 +0000 (22:40 +0000)]
hw/xen: Implement EVTCHNOP_bind_virq
Add the array of virq ports to each vCPU so that we can deliver timers,
debug ports, etc. Global virqs are allocated against vCPU 0 initially,
but can be migrated to other vCPUs (when we implement that).
The kernel needs to know about VIRQ_TIMER in order to accelerate timers,
so tell it via KVM_XEN_VCPU_ATTR_TYPE_TIMER. Also save/restore the value
of the singleshot timer across migration, as the kernel will handle the
hypercalls automatically now.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Tue, 13 Dec 2022 17:20:46 +0000 (17:20 +0000)]
hw/xen: Implement EVTCHNOP_unmask
This finally comes with a mechanism for actually injecting events into
the guest vCPU, with all the atomic-test-and-set that's involved in
setting the bit in the shinfo, then the index in the vcpu_info, and
injecting either the lapic vector as MSI, or letting KVM inject the
bare vector.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Tue, 13 Dec 2022 13:57:44 +0000 (13:57 +0000)]
hw/xen: Implement EVTCHNOP_close
It calls an internal close_port() helper which will also be used from
EVTCHNOP_reset and will actually do the work to disconnect/unbind a port
once any of that is actually implemented in the first place.
That in turn calls a free_port() internal function which will be in
error paths after allocation.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
David Woodhouse [Fri, 16 Dec 2022 14:32:25 +0000 (14:32 +0000)]
i386/xen: Add support for Xen event channel delivery to vCPU
The kvm_xen_inject_vcpu_callback_vector() function will either deliver
the per-vCPU local APIC vector (as an MSI), or just kick the vCPU out
of the kernel to trigger KVM's automatic delivery of the global vector.
Support for asserting the GSI/PCI_INTX callbacks will come later.
Also add kvm_xen_get_vcpu_info_hva() which returns the vcpu_info of
a given vCPU.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Fri, 16 Dec 2022 14:02:29 +0000 (14:02 +0000)]
hw/xen: Add xen_evtchn device for event channel emulation
Include basic support for setting HVM_PARAM_CALLBACK_IRQ to the global
vector method HVM_PARAM_CALLBACK_TYPE_VECTOR, which is handled in-kernel
by raising the vector whenever the vCPU's vcpu_info->evtchn_upcall_pending
flag is set.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Ankur Arora [Tue, 6 Dec 2022 11:14:07 +0000 (11:14 +0000)]
i386/xen: implement HVMOP_set_param
This is the hook for adding the HVM_PARAM_CALLBACK_IRQ parameter in a
subsequent commit.
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Split out from another commit] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
The HVMOP_set_evtchn_upcall_vector hypercall sets the per-vCPU upcall
vector, to be delivered to the local APIC just like an MSI (with an EOI).
This takes precedence over the system-wide delivery method set by the
HVMOP_set_param hypercall with HVM_PARAM_CALLBACK_IRQ. It's used by
Windows and Xen (PV shim) guests but normally not by Linux.
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Rework for upstream kernel changes and split from HVMOP_set_param] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Thu, 28 Jun 2018 16:36:19 +0000 (12:36 -0400)]
i386/xen: implement HYPERVISOR_event_channel_op
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Ditch event_channel_op_compat which was never available to HVM guests] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Mon, 18 Jun 2018 16:26:44 +0000 (12:26 -0400)]
i386/xen: implement HYPERVISOR_vcpu_op
This is simply when guest tries to register a vcpu_info
and since vcpu_info placement is optional in the minimum ABI
therefore we can just fail with -ENOSYS
Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Mon, 18 Jun 2018 16:17:42 +0000 (12:17 -0400)]
i386/xen: implement HYPERVISOR_memory_op
Specifically XENMEM_add_to_physmap with space XENMAPSPACE_shared_info to
allow the guest to set its shared_info page.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Use the xen_overlay device, add compat support] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Mon, 12 Dec 2022 14:03:41 +0000 (14:03 +0000)]
i386/xen: manage and save/restore Xen guest long_mode setting
Xen will "latch" the guest's 32-bit or 64-bit ("long mode") setting when
the guest writes the MSR to fill in the hypercall page, or when the guest
sets the event channel callback in HVM_PARAM_CALLBACK_IRQ.
KVM handles the former and sets the kernel's long_mode flag accordingly.
The latter will be handled in userspace. Keep them in sync by noticing
when a hypercall is made in a mode that doesn't match qemu's idea of
the guest mode, and resyncing from the kernel. Do that same sync right
before serialization too, in case the guest has set the hypercall page
but hasn't yet made a system call.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Mon, 12 Dec 2022 23:40:45 +0000 (23:40 +0000)]
i386/xen: add pc_machine_kvm_type to initialize XEN_EMULATE mode
The xen_overlay device (and later similar devices for event channels and
grant tables) need to be instantiated. Do this from a kvm_type method on
the PC machine derivatives, since KVM is only way to support Xen emulation
for now.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Wed, 7 Dec 2022 09:19:31 +0000 (09:19 +0000)]
hw/xen: Add xen_overlay device for emulating shared xenheap pages
For the shared info page and for grant tables, Xen shares its own pages
from the "Xen heap" to the guest. The guest requests that a given page
from a certain address space (XENMAPSPACE_shared_info, etc.) be mapped
to a given GPA using the XENMEM_add_to_physmap hypercall.
To support that in qemu when *emulating* Xen, create a memory region
(migratable) and allow it to be mapped as an overlay when requested.
Xen theoretically allows the same page to be mapped multiple times
into the guest, but that's hard to track and reinstate over migration,
so we automatically *unmap* any previous mapping when creating a new
one. This approach has been used in production with.... a non-trivial
number of guests expecting true Xen, without any problems yet being
noticed.
This adds just the shared info page for now. The grant tables will be
a larger region, and will need to be overlaid one page at a time. I
think that means I need to create separate aliases for each page of
the overall grant_frames region, so that they can be mapped individually.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Wed, 14 Dec 2022 21:50:41 +0000 (21:50 +0000)]
i386/xen: Implement SCHEDOP_poll and SCHEDOP_yield
They both do the same thing and just call sched_yield. This is enough to
stop the Linux guest panicking when running on a host kernel which doesn't
intercept SCHEDOP_poll and lets it reach userspace.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
It allows to shutdown itself via hypercall with any of the 3 reasons:
1) self-reboot
2) shutdown
3) crash
Implementing SCHEDOP_shutdown sub op let us handle crashes gracefully rather
than leading to triple faults if it remains unimplemented.
In addition, the SHUTDOWN_soft_reset reason is used for kexec, to reset
Xen shared pages and other enlightenments and leave a clean slate for the
new kernel without the hypervisor helpfully writing information at
unexpected addresses.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Ditch sched_op_compat which was never available for HVM guests,
Add SCHEDOP_soft_reset] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Thu, 14 Jun 2018 12:29:45 +0000 (08:29 -0400)]
i386/xen: implement HYPERVISOR_xen_version
This is just meant to serve as an example on how we can implement
hypercalls. xen_version specifically since Qemu does all kind of
feature controllability. So handling that here seems appropriate.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Implement kvm_gva_rw() safely] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Wed, 13 Jun 2018 14:14:31 +0000 (10:14 -0400)]
i386/xen: handle guest hypercalls
This means handling the new exit reason for Xen but still
crashing on purpose. As we implement each of the hypercalls
we will then return the right return code.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Add CPL to hypercall tracing, disallow hypercalls from CPL > 0] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Joao Martins [Tue, 19 Jun 2018 10:44:46 +0000 (06:44 -0400)]
xen-platform: allow its creation with XEN_EMULATE mode
The only thing we need to fix to make this build is the PIO hack which
sets the BIOS memory areas to R/W v.s. R/O. Theoretically we could hook
that up to the PAM registers on the emulated PIIX, but in practice
nobody cares, so just leave it doing nothing.
Now it builds without actual Xen, move it to CONFIG_XEN_BUS to include it
in the KVM-only builds.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Fri, 16 Dec 2022 11:05:29 +0000 (11:05 +0000)]
i386/hvm: Set Xen vCPU ID in KVM
There are (at least) three different vCPU ID number spaces. One is the
internal KVM vCPU index, based purely on which vCPU was chronologically
created in the kernel first. If userspace threads are all spawned and
create their KVM vCPUs in essentially random order, then the KVM indices
are basically random too.
The second number space is the APIC ID space, which is consistent and
useful for referencing vCPUs. MSIs will specify the target vCPU using
the APIC ID, for example, and the KVM Xen APIs also take an APIC ID
from userspace whenever a vCPU needs to be specified (as opposed to
just using the appropriate vCPU fd).
The third number space is not normally relevant to the kernel, and is
the ACPI/MADT/Xen CPU number which corresponds to cs->cpu_index. But
Xen timer hypercalls use it, and Xen timer hypercalls *really* want
to be accelerated in the kernel rather than handled in userspace, so
the kernel needs to be told.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Tue, 6 Dec 2022 10:48:53 +0000 (10:48 +0000)]
i386/kvm: handle Xen HVM cpuid leaves
Introduce support for emulating CPUID for Xen HVM guests. It doesn't make
sense to advertise the KVM leaves to a Xen guest, so do Xen unconditionally
when the xen-version machine property is set.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Obtain xen_version from KVM property, make it automatic] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Sat, 3 Dec 2022 17:51:13 +0000 (09:51 -0800)]
i386/kvm: Add xen-version KVM accelerator property and init KVM Xen support
This just initializes the basic Xen support in KVM for now. Only permitted
on TYPE_PC_MACHINE because that's where the sysbus devices for Xen heap
overlay, event channel, grant tables and other stuff will exist. There's
no point having the basic hypercall support if nothing else works.
Provide sysemu/kvm_xen.h and a kvm_xen_get_caps() which will be used
later by support devices.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
David Woodhouse [Tue, 6 Dec 2022 09:03:48 +0000 (09:03 +0000)]
xen: add CONFIG_XEN_BUS and CONFIG_XEN_EMU options for Xen emulation
The XEN_EMU option will cover core Xen support in target/, which exists
only for x86 with KVM today but could theoretically also be implemented
on Arm/Aarch64 and with TCG or other accelerators (if anyone wants to
run the gauntlet of struct layout compatibility, errno mapping, and the
rest of that fui).
It will also cover the support for architecture-independent grant table
and event channel support which will be added in hw/i386/kvm/ (on the
basis that the non-KVM support is very theoretical and making it not use
KVM directly seems like gratuitous overengineering at this point).
The XEN_BUS option is for the xenfv platform support, which will now be
used both by XEN_EMU and by real Xen.
The XEN option remains dependent on the Xen runtime libraries, and covers
support for real Xen. Some code which currently resides under CONFIG_XEN
will be moving to CONFIG_XEN_BUS over time as the direct dependencies on
Xen runtime libraries are eliminated. The Xen PCI platform device will
also reside under CONFIG_XEN_BUS.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
Joao Martins [Wed, 13 Feb 2019 17:29:47 +0000 (12:29 -0500)]
include: import Xen public headers to include/standard-headers/
There are already some partial headers in include/hw/xen/interface/
which will be removed once we migrate users to the new location.
To start with, define __XEN_TOOLS__ in hw/xen/xen.h to ensure that any
internal definitions needed by Xen toolstack libraries are present
regardless of the order in which the headers are included. A reckoning
will come later, once we make the PV backends work in emulation and
untangle the headers for Xen-native vs. generic parts.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
[dwmw2: Update to Xen public headers from 4.16.2 release, add some in io/,
define __XEN_TOOLS__ in hw/xen/xen.h] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org>
* tag 'trivial-branch-for-8.0-pull-request' of https://gitlab.com/laurent_vivier/qemu:
hw/ssi/sifive_spi.c: spelling: reigster
hw/cxl/cxl-host: Fix an error message typo
hw/cxl/cxl-cdat.c: spelling: missmatch
hw/pvrdma: Protect against buggy or malicious guest driver
ccid-card-emulated: fix cast warning/error
hw/i386/pc: Remove unused 'owner' argument from pc_pci_as_mapping_init
tests/qtest/test-hmp: Improve the check for verbose mode
hw/usb: Mark the XLNX_VERSAL-related files as target-independent
hw/intc: Mark more interrupt-controller files as target independent
hw/cpu: Mark arm11 and realview mpcore as target-independent code
hw/arm: Move various units to softmmu_ss[]
hw/tpm: Move tpm_ppi.c out of target-specific source set
hw/intc: Move some files out of the target-specific source set
hw/display: Move omap_lcdc.c out of target-specific source set
Call qemu_socketpair() instead of socketpair() when possible
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Peter Maydell [Wed, 18 Jan 2023 19:09:21 +0000 (19:09 +0000)]
Merge tag 'pull-request-2023-01-18' of https://gitlab.com/thuth/qemu into staging
* Fix the FreeBSD CI jobs in Gitlab by upgrading the packages in the beginning
* Fix the Haiku VM test by updating it to r1beta4
* Allow "make uninstall"
* Rename TARGET_FMT_plx to HWADDR_FMT_plx
* Some small qtest fixes/improvements
* Check for valid amount of CPUs before starting a secure execution s390x guest
* tag 'pull-request-2023-01-18' of https://gitlab.com/thuth/qemu:
s390x/pv: Implement a CGS check helper
tests/vm/haiku.x86_64: Update the Haiku VM to Beta 4
tests/qtest/libqos/e1000e: Remove duplicate register definitions
tests/qtest/e1000e-test: Fix the code style
tests/qtest: Restrict bcm2835-dma-test to CONFIG_RASPI
MAINTAINERS: Remove bouncing mail address from Kamil Rytarowski
bulk: Rename TARGET_FMT_plx -> HWADDR_FMT_plx
Makefile: allow 'make uninstall'
Upgrade all packages in the FreeBSD VMs to ensure the freshness
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Cédric Le Goater [Mon, 16 Jan 2023 17:46:05 +0000 (18:46 +0100)]
s390x/pv: Implement a CGS check helper
When a protected VM is started with the maximum number of CPUs (248),
the service call providing information on the CPUs requires more
buffer space than allocated and QEMU disgracefully aborts :
LOADPARM=[........]
Using virtio-blk.
Using SCSI scheme.
...................................................................................
qemu-system-s390x: KVM_S390_MEM_OP failed: Argument list too long
When protected virtualization is initialized, compute the maximum
number of vCPUs supported by the machine and return useful information
to the user before the machine starts in case of error.
Suggested-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-Id: <20230116174607.2459498-2-clg@kaod.org> Signed-off-by: Thomas Huth <thuth@redhat.com>
Thomas Huth [Mon, 16 Jan 2023 08:30:14 +0000 (09:30 +0100)]
tests/vm/haiku.x86_64: Update the Haiku VM to Beta 4
The old Haiku VM based on Beta 3 does not work anymore since it
fails to install the additional packages now that Beta 4 has been
released. Thanks to Alexander von Gluck IV for providing a new
image based on Beta 4, we can now upgrade the test image in our
QEMU CI, too, to get this working again.
Note that Haiku Beta 4 apparently finally fixed the issue with
the enumeration of the virtio-block devices (see the ticket at
https://dev.haiku-os.org/ticket/16512 ) - the tarball disk can
now be found at index 1 instead of index 0.
Message-Id: <20230116083014.55647-1-thuth@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Thomas Huth <thuth@redhat.com>
The register definitions in tests/qtest/libqos/e1000e.h had names
different from hw/net/e1000_regs.h, which made it hard to understand
what test codes corresponds to the implementation. Use
hw/net/e1000_regs.h from tests/qtest/libqos/e1000e.c to remove
these duplications.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230114035919.35251-20-akihiko.odaki@daynix.com> Signed-off-by: Thomas Huth <thuth@redhat.com>
Fabiano Rosas [Fri, 13 Jan 2023 14:04:13 +0000 (11:04 -0300)]
tests/qtest: Restrict bcm2835-dma-test to CONFIG_RASPI
We will soon enable the build without TCG, which does not support many
machines, so only run the bcm2835-dma-test when the corresponding
machine is present.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Message-Id: <20230113140419.4013-23-farosas@suse.de> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Thomas Huth <thuth@redhat.com>
Thomas Huth [Fri, 13 Jan 2023 08:17:35 +0000 (09:17 +0100)]
MAINTAINERS: Remove bouncing mail address from Kamil Rytarowski
When sending mail to Kamil's address, it's bouncing with a message
that the mailbox is full. This already happens since summer 2022,
and the last message that Kamil sent to the qemu-devel mailing list
is from November 2021 (as far as I can see), so we unfortunately
have to assume that this e-mail address is not valid anymore.
Message-Id: <20230113081735.1148057-1-thuth@redhat.com> Signed-off-by: Thomas Huth <thuth@redhat.com>
Since hwaddr's size can be *different* from target_ulong, it is
very confusing to read one of its format using the 'TARGET_FMT_'
prefix, normally used for the target_long / target_ulong types:
Apparently this format was missed during commit a8170e5e97
("Rename target_phys_addr_t to hwaddr"), so complete it by
doing a bulk-rename with:
$ sed -i -e s/TARGET_FMT_plx/HWADDR_FMT_plx/g $(git grep -l TARGET_FMT_plx)
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230110212947.34557-1-philmd@linaro.org>
[thuth: Fix some warnings from checkpatch.pl along the way] Signed-off-by: Thomas Huth <thuth@redhat.com>