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3 years agoIOMMU/PCI: don't let domain cleanup continue when device de-assignment failed
Jan Beulich [Fri, 25 Jun 2021 12:06:55 +0000 (14:06 +0200)]
IOMMU/PCI: don't let domain cleanup continue when device de-assignment failed

Failure here could in principle mean the device may still be issuing DMA
requests, which would continue to be translated by the page tables the
device entry currently points at. With this we cannot allow the
subsequent cleanup step of freeing the page tables to occur, to prevent
use-after-free issues. We would need to accept, for the time being, that
in such a case the remaining domain resources will all be leaked, and
the domain will continue to exist as a zombie.

However, with flushes no longer timing out (and with proper timeout
detection for device I/O TLB flushing yet to be implemented), there's no
way anymore for failures to occur, except due to bugs elsewhere. Hence
the change here is merely a "just in case" one.

In order to continue the loop in spite of an error, we can't use
pci_get_pdev_by_domain() anymore. I have no idea why it was used here in
the first place, instead of the cheaper list iteration.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
3 years agolibxencall: Bump SONAME following new functionality
Andrew Cooper [Thu, 24 Jun 2021 17:49:14 +0000 (18:49 +0100)]
libxencall: Bump SONAME following new functionality

Fixes: bef64f2c00 ("libxencall: introduce variant of xencall2() returning long")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
3 years agotools/xenstored: Correctly read the requests header from the stream
Julien Grall [Fri, 25 Jun 2021 06:45:22 +0000 (07:45 +0100)]
tools/xenstored: Correctly read the requests header from the stream

Commit c0fe360f42 ("tools/xenstored: Extend restore code to handle
multiple input buffer") extend the read_buffered_state() to support
multiple input buffers. Unfortunately, the commit didn't go far
enough and still used sc->data (start of the buffers) for retrieving
the header. This would lead to read the wrong headers for second and
follow-up commands.

Use data in place for sc->data for the source of the memcpy()s.

Fixes: c0fe360f42 ("tools/xenstored: Extend restore code to handle multiple input buffer")
Reported-by: Raphael Ning <raphning@amazon.com>
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: Remove redundant check in socket_can_process()
Julien Grall [Thu, 24 Jun 2021 14:55:03 +0000 (15:55 +0100)]
tools/xenstored: Remove redundant check in socket_can_process()

Commit 3adfb50315d9 ("tools/xenstored: Introduce a wrapper for
conn->funcs->can_{read, write}") consolidated the check
!conn->is_ignored in two new wrappers.

This means the check in socket_can_process() is now redundant. In
fact it should have been removed in orignal commit (as it was done
for the domain helpers).

Reported-by: Raphael Ning <raphning@amazon.com
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agolibxc: make xc_domain_maximum_gpfn() endianness-agnostic
Jan Beulich [Thu, 24 Jun 2021 14:40:57 +0000 (16:40 +0200)]
libxc: make xc_domain_maximum_gpfn() endianness-agnostic

libxc generally uses uint32_t to represent domain IDs. This is fine as
long as addresses of such variables aren't taken, to then pass into
hypercalls: To the hypervisor, a domain ID is a 16-bit value. Introduce
a wrapper struct to deal with the issue. (On architectures with
arguments passed in registers, an intermediate variable would have been
created by the compiler already anyway, just one of the wrong type.)

The public interface change is both source and binary compatible for
the architectures we currently support.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agolibxencall: drop bogus mentioning of xencall6()
Jan Beulich [Thu, 24 Jun 2021 14:39:55 +0000 (16:39 +0200)]
libxencall: drop bogus mentioning of xencall6()

There's no xencall6(), so the version script also shouldn't mention it.
If such a function would ever appear, it shouldn't land in version 1.0.

No change to the generated binary, nor abi-dumper's view of the object.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agolibxc: use multicall for memory-op on Linux (and Solaris)
Jan Beulich [Thu, 24 Jun 2021 14:39:26 +0000 (16:39 +0200)]
libxc: use multicall for memory-op on Linux (and Solaris)

Some sub-functions, XENMEM_maximum_gpfn and XENMEM_maximum_ram_page in
particular, can return values requiring more than 31 bits to represent.
Hence we cannot issue the hypercall directly when the return value of
ioctl() is used to propagate this value. This is the case for Linux
and Solaris (and hence needs changing), while the BSDs avoid using the
return value for dual purposes altogether, and MiniOS already wraps all
hypercalls in a multicall.

Suggested-by: Jürgen Groß <jgross@suse.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agolibxencall: introduce variant of xencall2() returning long
Jan Beulich [Thu, 24 Jun 2021 14:39:02 +0000 (16:39 +0200)]
libxencall: introduce variant of xencall2() returning long

Some hypercalls, memory-op in particular, can return values requiring
more than 31 bits to represent. Hence the underlying layers need to make
sure they won't truncate such values.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agolibxencall: osdep_hypercall() should return long
Jan Beulich [Thu, 24 Jun 2021 14:38:37 +0000 (16:38 +0200)]
libxencall: osdep_hypercall() should return long

Some hypercalls, memory-op in particular, can return values requiring
more than 31 bits to represent. Hence the underlying layers need to make
sure they won't truncate such values. (Note that for Solaris the
function also gets renamed, to match the other OSes.)

Due to them merely propagating ioctl()'s return value, this change is
benign on Linux and Solaris. IOW there's an actual effect here only for
the BSDs and MiniOS, but even then further adjustments are needed at the
xencall<N>() level.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
3 years agox86/HVM: wire up multicalls
Jan Beulich [Thu, 24 Jun 2021 14:35:39 +0000 (16:35 +0200)]
x86/HVM: wire up multicalls

To be able to use them from, in particular, the tool stack, they need to
be supported for all guest types. Note that xc_resource_op() already
does, so would not work without this on PVH Dom0.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Begrudingly acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
3 years agoVT-d: drop/move a few QI related constants
Jan Beulich [Thu, 24 Jun 2021 14:30:51 +0000 (16:30 +0200)]
VT-d: drop/move a few QI related constants

Replace uses of QINVAL_ENTRY_ORDER and QINVAL_INDEX_SHIFT, such that
the constants can be dropped. Move the remaining QINVAL_* ones to the
single source file using them.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agoVT-d: centralize mapping of QI entries
Jan Beulich [Thu, 24 Jun 2021 14:30:32 +0000 (16:30 +0200)]
VT-d: centralize mapping of QI entries

Introduce a helper function to reduce redundancy. Take the opportunity
to express the logic without using the somewhat odd QINVAL_ENTRY_ORDER.
Also take the opportunity to uniformly unmap after updating queue tail
and dropping the lock (like was done so far only by
queue_invalidate_context_sync()).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agoVT-d: don't lose errors when flushing TLBs on multiple IOMMUs
Jan Beulich [Thu, 24 Jun 2021 14:30:06 +0000 (16:30 +0200)]
VT-d: don't lose errors when flushing TLBs on multiple IOMMUs

While no longer an immediate problem with flushes no longer timing out,
errors (if any) get properly reported by iommu_flush_iotlb_{dsi,psi}().
Overwriting such an error with, perhaps, a success indicator received
from another IOMMU will misguide callers. Record the first error, but
don't bail from the loop (such that further necessary invalidation gets
carried out on a best effort basis).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agoVT-d: clear_fault_bits() should clear all fault bits
Jan Beulich [Thu, 24 Jun 2021 14:29:42 +0000 (16:29 +0200)]
VT-d: clear_fault_bits() should clear all fault bits

If there is any way for one fault to be left set in the recording
registers, there's no reason there couldn't also be multiple ones. If
PPF set set (being the OR or all F fields), simply loop over the entire
range of fault recording registers, clearing F everywhere.

Since PPF is a r/o bit, also remove it from DMA_FSTS_FAULTS (arguably
the constant's name is ambiguous as well).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agoVT-d: adjust domid map updating when unmapping context
Jan Beulich [Thu, 24 Jun 2021 14:29:13 +0000 (16:29 +0200)]
VT-d: adjust domid map updating when unmapping context

When an earlier error occurred, cleaning up the domid mapping data is
wrong, as references likely still exist. The only exception to this is
when the actual unmapping worked, but some flush failed (supposedly
impossible after XSA-373). The guest will get crashed in such a case
though, so add fallback cleanup to domain destruction to cover this
case. This in turn makes it desirable to silence the dprintk() in
domain_iommu_domid().

Note that no error will be returned anymore when the lookup fails - in
the common case lookup failure would already have caused
domain_context_unmap_one() to fail, yet even from a more general
perspective it doesn't look right to fail domain_context_unmap() in such
a case when this was the last device, but not when any earlier unmap was
otherwise successful.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agoVT-d: undo device mappings upon error
Jan Beulich [Thu, 24 Jun 2021 14:28:25 +0000 (16:28 +0200)]
VT-d: undo device mappings upon error

When
 - flushes (supposedly not possible anymore after XSA-373),
 - secondary mappings for legacy PCI devices behind bridges,
 - secondary mappings for chipset quirks, or
 - find_upstream_bridge() invocations
fail, the successfully established device mappings should not be left
around.

Further, when (parts of) unmapping fail, simply returning an error is
typically not enough. Crash the domain instead in such cases, arranging
for domain cleanup to continue in a best effort manner despite such
failures.

Finally make domain_context_unmap()'s error behavior consistent in the
legacy PCI device case: Don't bail from the function in one special
case, but always just exit the switch statement.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agotools/xenstored: Don't crash xenstored when Live-Update is cancelled
Julien GralL [Thu, 24 Jun 2021 11:15:49 +0000 (12:15 +0100)]
tools/xenstored: Don't crash xenstored when Live-Update is cancelled

As Live-Update is asynchronous, it is possible to receive a request to
cancel it (either on the same connection or from a different one).

Currently, this will crash xenstored because do_lu_start() assumes
lu_status will be valid. This is not the case when Live-Update has been
cancelled. This will result to dereference a NULL pointer and
crash Xenstored.

Rework do_lu_start() to check if lu_status is NULL and return an
error in this case.

Fixes: af216a99fb ("tools/xenstore: add the basic framework for doing the live update")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: Delay new transaction while Live-Update is pending
Julien Grall [Thu, 24 Jun 2021 11:14:56 +0000 (12:14 +0100)]
tools/xenstored: Delay new transaction while Live-Update is pending

At the moment, Live-Update will, by default, not proceed if there are
in-flight transactions. It is possible force it by passing -F but this
will break any connection with in-flight transactions.

There are PV drivers out that may never terminate some transaction. On
host running such guest, we would need to use -F. Unfortunately, this
also risks to break well-behaving guests (and even dom0) because
Live-Update will happen as soon as the timeout is hit.

Ideally, we would want to preserve transactions but this requires
some work and a lot of testing to be able to use it in production.

As a stop gap, we want to limit the damage of -F. This patch will delay
any transactions that are started after Live-Update has been requested.

If the request cannot be delayed, the connection will be stalled to
avoid loosing requests.

If the connection has already a pending transaction before Live-Update,
then new transaction will not be delayed. This is to avoid the connection
to stall.

With this stop gap in place, domains with long running transactions will
still break when using -F, but other domains which starts a transaction
in the middle of Live-Update will continue to work.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: Dump delayed requests
Julien Grall [Thu, 24 Jun 2021 11:12:54 +0000 (12:12 +0100)]
tools/xenstored: Dump delayed requests

Currently, only Live-Update request can be delayed. In a follow-up,
we will want to delay more requests (e.g. transaction start).
Therefore we want to preserve delayed requests across Live-Update.

Delayed requests are just complete "in" buffer. So the code is
refactored to allow sharing the code to dump "in" buffer.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agomaintainers: adding new reviewer for xsm
Daniel P. Smith [Thu, 17 Jun 2021 23:49:55 +0000 (19:49 -0400)]
maintainers: adding new reviewer for xsm

Would like to add myself as a reviewer for XSM.

Signed-off-by: Daniel P. Smith <dpsmith@apertussolutions.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agoiommu/arm: ipmmu-vmsa: Add compatible for Renesas R-Car M3-W+ SoC
Oleksandr Tyshchenko [Mon, 14 Jun 2021 19:18:12 +0000 (22:18 +0300)]
iommu/arm: ipmmu-vmsa: Add compatible for Renesas R-Car M3-W+ SoC

The "renesas,r8a77961" string identifies M3-W+ (aka M3-W ES3.0)
instead of "renesas,r8a7796" since Linux commit:
"9c9f7891093b02eb64ca4e1c7ab776a4296c058f soc: renesas: Identify R-Car M3-W+".
Add new compatible to the Xen driver.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Julien Grall <jgrall@amazon.com>
3 years agotools/xenstored: Extend restore code to handle multiple input buffer
Julien Grall [Thu, 24 Jun 2021 10:41:00 +0000 (11:41 +0100)]
tools/xenstored: Extend restore code to handle multiple input buffer

Currently, the restore code is considering the stream will contain at
most one in-flight request per connection. In a follow-up changes, we
will want to transfer multiple in-flight requests.

The function read_state_buffered() is now extended to restore multiple
in-flight request. Complete requests will be queued as delayed
requests, if there a partial request (only the last one can) then it
will used as the current in-flight request.

Note that we want to bypass the quota check for delayed requests as
the new Xenstore may have a lower limit.

Lastly, there is no need to change the specification as there was
no restriction on the number of in-flight requests preserved.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: delay_request: don't assume conn->in == in
Julien Grall [Thu, 24 Jun 2021 08:08:56 +0000 (09:08 +0100)]
tools/xenstored: delay_request: don't assume conn->in == in

delay_request() is currently assuming that the request delayed is
always conn->in. This is currently correct, but it is a call for
a latent bug as the function allows the caller to specify any request.

To prevent any future surprise, check if the request delayed is the
current one.

Fixes: c5ca1404b4 ("tools/xenstore: add support for delaying execution of a xenstore request")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: Introduce a wrapper for conn->funcs->can_{read, write}
Julien Grall [Thu, 24 Jun 2021 08:08:42 +0000 (09:08 +0100)]
tools/xenstored: Introduce a wrapper for conn->funcs->can_{read, write}

Currently, the callbacks can_read and can_write are called directly. This
doesn't allow us to add generic check and therefore requires duplication.

At the moment, one check that could benefit to be common is whether the
connection should ignored. The position is slightly different between
domain and socket because for the latter we want to check the state of
the file descriptor first.

In follow-up patches, there will be more potential generic checks.

This patch provides wrappers to read/write a connection and move
the check ->is_ignored after the callback for everyone.

This also requires to replace the direct call to domain_can_read()
and domain_can_write() with the new wrapper. At the same time,
both functions can now be static. Note that the implementations need
to be moved earlier in the file xenstored_domain.c to avoid
declaring the prototype.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: xenstored_core.h should include fcntl.h
Julien Grall [Thu, 24 Jun 2021 08:07:52 +0000 (09:07 +0100)]
tools/xenstored: xenstored_core.h should include fcntl.h

xenstored_core.h will consider live-udpate is not supported if
O_CLOEXEC doesn't exist. However, the header doesn't include the one
defining O_CLOEXEC (i.e. fcntl.h). This means that depending on
the header included, some source file will think Live-Update is not
supported.

I am not aware of any issue with the existing. Therefore this is just
a latent bug so far.

Prevent any potential issue by including fcntl.h in xenstored_core.h

Fixes: cd831ee438 ("tools/xenstore: handle CLOEXEC flag for local files and pipes")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: Limit the number of requests a connection can delay
Julien Grall [Thu, 24 Jun 2021 08:07:30 +0000 (09:07 +0100)]
tools/xenstored: Limit the number of requests a connection can delay

Currently, only liveupdate request can be delayed. The request can only
be performed by a privileged connection (e.g. dom0). So it is fine to
have no limits.

In a follow-up patch we will want to delay request for unprivileged
connection as well. So it is best to apply a limit.

For now and for simplicity, only a single request can be delayed
for a given unprivileged connection.

Take the opportunity to tweak the prototype and provide a way to
bypass the quota check. This would be useful when the function
is called from the restore code.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstore: Don't assume conn->in points to the LU request
Julien Grall [Thu, 24 Jun 2021 08:06:58 +0000 (09:06 +0100)]
tools/xenstore: Don't assume conn->in points to the LU request

call_delayed() is currently assuming that conn->in is NULL when
handling delayed request. However, the connection is not paused.
Therefore new request can be processed and conn->in may be non-NULL
if we have only received a partial request.

Furthermore, as we overwrite conn->in, the current partial request
will not be transferred. This will result to corrupt the connection.

Rather than updating conn->in, stash the LU request in lu_status and
let each callback for delayed request to update conn->in when
necessary.

To keep a sane interface, the code to write the "OK" response the
LU request is moved in xenstored_core.c.

Fixes: c5ca1404b4 ("tools/xenstore: add support for delaying execution of a xenstore request")
Fixes: ed6eebf17d ("tools/xenstore: dump the xenstore state for live update")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agotools/xenstored: Introduce lu_get_connection() and use it
Julien Grall [Thu, 24 Jun 2021 08:02:59 +0000 (09:02 +0100)]
tools/xenstored: Introduce lu_get_connection() and use it

At the moment, dump_state_buffered_data() is taking two connections
in parameters (one is the connection to dump, the other is the
connection used to request LU). The naming doesn't help to
distinguish (c vs conn) them and this already lead to several mistake
while modifying the function.

To remove the confusion, introduce an help lu_get_connection() that
will return the connection used to request LU and use it
in place of the existing parameter.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
3 years agoMAINTAINERS: Add myself as reviewers for tools/xenstore
Julien Grall [Thu, 24 Jun 2021 08:02:56 +0000 (09:02 +0100)]
MAINTAINERS: Add myself as reviewers for tools/xenstore

I would like to help reviewing Xenstored patches. It is more convenient
to find them if I am CCed.

Signed-off-by: Julien Grall <julien@xen.org>
Acked-by: Juergen Gross <jgross@suse.com>
3 years agoRevert "tools/firmware/ovmf: Use OvmfXen platform file is exist"
Andrew Cooper [Tue, 22 Jun 2021 15:14:53 +0000 (16:14 +0100)]
Revert "tools/firmware/ovmf: Use OvmfXen platform file is exist"

This reverts commit aad7b5c11d51d57659978e04702ac970906894e8.

The change from OvmfX64 to OvmfXen causes a change in behaviour, whereby
OvmfXen maps its shared info page at the top of address space.  When trying to
migrate such a domain, XENMEM_maximum_gpfn returns a very large value.  This
has uncovered multiple issues:

 1) The userspace hypercall wrappers truncate all return values to int on
    Linux and Solaris, even on 64bit.  This needs fixing in libxenctrl.
 2) 32bit toolstacks can't migrate any domain with RAM above the 2^40 mark,
    because of virtual address constraints.  This needs fixing in OVMF.

Fixes for both of these aren't completely trivial.  Revert the change to
unblock staging in the meantime.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
3 years agogolang/xenlight: do not negate ret when converting to Error
Nick Rosbrook [Mon, 24 May 2021 20:36:52 +0000 (16:36 -0400)]
golang/xenlight: do not negate ret when converting to Error

Commit 871e51d2d4 changed the sign on the xenlight error types (making
the values negative, same as the C-generated constants), but failed to
remove the code changing the sign before casting to Error().  This
results in error strings like "libxl error: <x>", rather than the
correct message. Fix all occurrances of this by running:

  gofmt -w -r 'Error(-ret) -> Error(ret)' xenlight.go

from tools/golang/xenlight.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: add SendTrigger wrapper
Nick Rosbrook [Mon, 24 May 2021 20:36:51 +0000 (16:36 -0400)]
golang/xenlight: add SendTrigger wrapper

Add a warpper around libxl_send_trigger.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: add DomainDestroy wrapper
Nick Rosbrook [Mon, 24 May 2021 20:36:50 +0000 (16:36 -0400)]
golang/xenlight: add DomainDestroy wrapper

Add a wrapper around libxl_domain_destroy.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: rename Ctx receivers to ctx
Nick Rosbrook [Mon, 24 May 2021 20:36:47 +0000 (16:36 -0400)]
golang/xenlight: rename Ctx receivers to ctx

As a matter of style, it is strange to see capitalized receiver names,
due to the significance of capitalized symbols in Go (although there is
in fact nothing special about a capitalized receiver name). Fix this in
xenlight.go by running:

  gofmt -w -r 'Ctx -> ctx' xenlight.go

from tools/golang/xenlight. There is no functional change.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: use struct pointers in keyed union fields
Nick Rosbrook [Mon, 24 May 2021 20:36:46 +0000 (16:36 -0400)]
golang/xenlight: use struct pointers in keyed union fields

Currently, when marshalig Go types with keyed union fields, we assign the
value of the struct (e.g. DomainBuildInfoTypeUnionHvm) which implements the
interface of the keyed union field (e.g. DomainBuildInfoTypeUnion).
As-is, this means that if a populated DomainBuildInfo is marshaled to
e.g. JSON, unmarshaling back to DomainBuildInfo will fail.

When the encoding/json is unmarshaling data into a Go type, and
encounters a JSON object, it basically can either marshal the data into
an empty interface, a map, or a struct. It cannot, however, marshal data
into an interface with at least one method defined on it (e.g.
DomainBuildInfoTypeUnion). Before this check is done, however, the
decoder will check if the Go type is a pointer, and dereference it if
so. It will then use the type of this value as the "target" type.

This means that if the TypeUnion field is populated with a
DomainBuildInfoTypeUnion, the decoder will see a non-empty interface and
fail. If the TypeUnion field is populated with a
*DomainBuildInfoTypeUnionHvm, it dereferences the pointer and sees a
struct instead, allowing decoding to continue normally.

Since there does not appear to be a strict need for NOT using pointers
in these fields, update code generation to set keyed union fields to
pointers of their implementing structs.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: export keyed union interface types
Nick Rosbrook [Mon, 24 May 2021 20:36:45 +0000 (16:36 -0400)]
golang/xenlight: export keyed union interface types

For structs that have a keyed union, e.g. DomainBuildInfo, the TypeUnion
field must be exported so that package users can get/set the fields
within. This means that users are aware of the existence of the
interface type used in those fields (see [1]), so it is awkward that the
interface itself is not exported. However, the single method within the
interface must remain unexported so that users cannot mistakenly "implement"
those interfaces.

Since there seems to be no reason to do otherwise, export the keyed
union interface types.

[1] https://pkg.go.dev/xenbits.xenproject.org/git-http/xen.git/tools/golang/xenlight?tab=doc#DeviceUsbdev

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: fix StringList toC conversion
Nick Rosbrook [Mon, 24 May 2021 20:36:43 +0000 (16:36 -0400)]
golang/xenlight: fix StringList toC conversion

The current implementation of StringList.toC does not correctly account
for how libxl_string_list is expected to be laid out in C, which is clear
when one looks at libxl_string_list_length in libxl.c. In particular,
StringList.toC does not account for the extra memory that should be
allocated for the "sentinel" entry. And, when using the "slice trick" to
create a slice that can address C memory, the unsafe.Pointer conversion
should be on a C.libxl_string_list, not *C.libxl_string_list.

Fix these problems by (1) allocating an extra slot in the slice used to
address the C memory, and explicity set the last entry to nil so the C
memory will be zeroed out, and (2) dereferencing csl in the
unsafe.Pointer conversion.

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agogolang/xenlight: update generated code
Nick Rosbrook [Mon, 24 May 2021 20:36:42 +0000 (16:36 -0400)]
golang/xenlight: update generated code

Re-generate code to reflect changes to libxl_types.idl from the
following commits:

0570d7f276 x86/msr: introduce an option for compatible MSR behavior selection
7e5cffcd1e viridian: allow vCPU hotplug for Windows VMs
9835246710 viridian: remove implicit limit of 64 VPs per partition

Signed-off-by: Nick Rosbrook <rosbrookn@ainfosec.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agox86/ept: force WB cache attributes for grant and foreign maps
Roger Pau Monné [Thu, 17 Jun 2021 16:00:57 +0000 (18:00 +0200)]
x86/ept: force WB cache attributes for grant and foreign maps

Force WB type for grants and foreign pages. Those are usually mapped
over unpopulated physical ranges in the p2m, and those ranges would
usually be UC in the MTRR state, which is unlikely to be the correct
cache attribute. It's also cumbersome (or even impossible) for the
guest to be setting the MTRR type for all those mappings as WB, as
MTRR ranges are finite.

Note that this is not an issue on AMD because WB cache attribute is
already set on grants and foreign mappings in the p2m and MTRR types
are ignored. Also on AMD Xen cannot force a cache attribute because of
the lack of ignore PAT equivalent, so the behavior here slightly
diverges between AMD and Intel (or EPT vs NPT/shadow).

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agox86/mtrr: move epte_get_entry_emt to p2m-ept.c
Roger Pau Monné [Thu, 17 Jun 2021 15:58:11 +0000 (17:58 +0200)]
x86/mtrr: move epte_get_entry_emt to p2m-ept.c

This is an EPT specific function, so it shouldn't live in the generic
mtrr file. Such movement is also needed for future work that will
require passing a p2m_type_t parameter to epte_get_entry_emt, and
making that type visible to the mtrr users is cumbersome and
unneeded.

Moving epte_get_entry_emt out of mtrr.c requires making the helper to
get the MTRR type of an address from the mtrr state public. While
there rename the function to start with the mtrr prefix, like other
mtrr related functions.

While there fix some of the types of the function parameters.

No functional change intended.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
3 years agotests: Introduce a TSX test
Andrew Cooper [Thu, 10 Jun 2021 11:34:45 +0000 (12:34 +0100)]
tests: Introduce a TSX test

See the comment at the top of test-tsx.c for details.

This covers various complexities encountered while trying to address the
recent TSX deprecation on client parts.

A sample run on KabyLake with latest microcode and default tsx= looks like
this:

  root@host# ./test-tsx
  TSX tests
    Got 8 CPUs
  Testing MSR_TSX_FORCE_ABORT consistency
    CPU0 val 0x3
  Testing MSR_TSX_CTRL consistency
  Testing RTM behaviour
    Got Abort
  Testing PV default/max policies
    Max: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
    Def: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
  Testing HVM default/max policies
    Max: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
    Def: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
  Testing PV guest
    Created d7
    Cur: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
    Cur: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
  Testing HVM guest
    Created d8
    Cur: RTM 0, HLE 0, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0
    Cur: RTM 1, HLE 1, TSX_FORCE_ABORT 0, RTM_ALWAYS_ABORT 0, TSX_CTRL 0

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
3 years agolibs/guest: Move struct xc_cpu_policy into xg_private.h
Andrew Cooper [Thu, 10 Jun 2021 11:57:42 +0000 (12:57 +0100)]
libs/guest: Move struct xc_cpu_policy into xg_private.h

... so tests can peek at the internals, without the structure being generally
available to users of the library.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/msr: Expose MSR_ARCH_CAPS in the raw and host policies
Andrew Cooper [Fri, 11 Jun 2021 10:37:53 +0000 (11:37 +0100)]
x86/msr: Expose MSR_ARCH_CAPS in the raw and host policies

MSR_ARCH_CAPS is still not supported for guests yet (other than the hardware
domain), until the toolstack learns how to construct an MSR policy.

However, we want access to the host ARCH_CAPS_TSX_CTRL value in particular for
testing purposes.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/platform: Permit reading the TSX control MSRs via XENPF_resource_op
Andrew Cooper [Thu, 10 Jun 2021 10:02:47 +0000 (11:02 +0100)]
x86/platform: Permit reading the TSX control MSRs via XENPF_resource_op

We are going to want this to write some tests with.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/platform: Improve MSR permission handling for XENPF_resource_op
Andrew Cooper [Thu, 10 Jun 2021 10:01:06 +0000 (11:01 +0100)]
x86/platform: Improve MSR permission handling for XENPF_resource_op

The logic to disallow writes to the TSC is out-of-place, and should be in
check_resource_access() rather than in resource_access().

Split the existing allow_access_msr() into two - msr_{read,write}_allowed() -
and move all permissions checks here.

Furthermore, guard access to MSR_IA32_CMT_{EVTSEL,CTR} to prohibit their use
on hardware which is lacking the QoS Monitoring feature.  Introduce
cpu_has_pqe to help with the logic.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agolibs/foreignmemory: Fix osdep_xenforeignmemory_map prototype
Anthony PERARD [Tue, 1 Jun 2021 15:41:47 +0000 (16:41 +0100)]
libs/foreignmemory: Fix osdep_xenforeignmemory_map prototype

Commit cf8c4d3d13b8 made some preparation to have one day
variable-length-array argument, but didn't declare the array in the
function prototype the same way as in the function definition. And now
GCC 11 complains about it.

Fixes: cf8c4d3d13b8 ("tools/libs/foreignmemory: pull array length argument to map forward")
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agox86: move .altinstr_replacement past _einittext
Jan Beulich [Tue, 15 Jun 2021 13:15:26 +0000 (15:15 +0200)]
x86: move .altinstr_replacement past _einittext

This section's contents do not represent part of actual hypervisor text,
so shouldn't be included in what is_kernel_inittext() or (while still
booting) is_active_kernel_text() report "true" for. Keep them in
.init.text though, as there's no real reason to have a separate section
for this in the final binary.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agox86/vpt: fully init timers before putting onto list
Jan Beulich [Tue, 15 Jun 2021 13:14:20 +0000 (15:14 +0200)]
x86/vpt: fully init timers before putting onto list

With pt_vcpu_lock() no longer acquiring the pt_migrate lock, parties
iterating the list and acting on the timers of the list entries will no
longer be kept from entering their loops by create_periodic_time()'s
holding of that lock. Therefore at least init_timer() needs calling
ahead of list insertion, but keep this and set_timer() together.

Fixes: 8113b02f0bf8 ("x86/vpt: do not take pt_migrate rwlock in some cases")
Reported-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
3 years agolibxl: Replace QMP command "change" by "blockdev-change-media"
Anthony PERARD [Tue, 11 May 2021 09:28:10 +0000 (10:28 +0100)]
libxl: Replace QMP command "change" by "blockdev-change-media"

"change" command as been removed in QEMU 6.0. We can use
"blockdev-change-medium" instead.

Using `id` with "blockdev-change-medium" requires a change to the QEMU
command line, introduced by:
    "libxl: Use -device for cd-rom drives"

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Use `id` with the "eject" QMP command
Anthony PERARD [Tue, 11 May 2021 09:28:09 +0000 (10:28 +0100)]
libxl: Use `id` with the "eject" QMP command

`device` parameter is deprecated since QEMU 2.8.

This requires changes to the command line introduced by:
    "libxl: Use -device for cd-rom drives"

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Export libxl__qmp_ev_qemu_compare_version
Anthony PERARD [Tue, 11 May 2021 09:28:08 +0000 (10:28 +0100)]
libxl: Export libxl__qmp_ev_qemu_compare_version

We are going to want to check QEMU's version in other places where we
can use libxl__ev_qmp_send.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Assert qmp_ev's state in qmp_ev_qemu_compare_version
Anthony PERARD [Tue, 11 May 2021 09:28:07 +0000 (10:28 +0100)]
libxl: Assert qmp_ev's state in qmp_ev_qemu_compare_version

We are supposed to read the version information only when qmp_ev is in
state "Connected" (that correspond to state==qmp_state_connected),
assert it so that the function isn't used too early.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Use -device for cd-rom drives
Anthony PERARD [Tue, 11 May 2021 09:28:06 +0000 (10:28 +0100)]
libxl: Use -device for cd-rom drives

This allows to set an `id` on the device instead of only the drive. We
are going to need the `id` with the "eject" and
"blockdev-change-media" QMP command as using `device` parameter on
those is deprecated. (`device` is the `id` of the `-drive` on the
command line).

We set the same `id` on both -device and -drive as QEMU doesn't
complain and we can then either do "eject id=$id" or "eject
device=$id".

Using "-drive + -device" instead of only "-drive" has been
available since at least QEMU 0.15, and seems to be the preferred way as it
separates the host part (-drive which describe the disk image location
and format) from the guest part (-device which describe the emulated
device). More information in qemu.git/docs/qdev-device-use.txt .

Changing the command line during migration for the cdrom seems fine.
Also the documentation about migration in QEMU explains that the device
state ID is "been formed from a bus name and device address", so
second IDE bus and first device address on bus is still thus and
doesn't matter if written "-drive if=ide,index=2" or "-drive
ide-cd,bus=ide.1,unit=0".
See qemu.git/docs/devel/migration.rst .

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Replace deprecated "cpu-add" QMP command by "device_add"
Anthony PERARD [Tue, 11 May 2021 09:28:05 +0000 (10:28 +0100)]
libxl: Replace deprecated "cpu-add" QMP command by "device_add"

The command "cpu-add" for CPU hotplug is deprecated and has been
removed from QEMU 6.0 (April 2021). We need to add cpus with the
command "device_add" now.

In order to find out which parameters to pass to "device_add" we first
make a call to "query-hotpluggable-cpus" which list the cpus drivers
and properties.

The algorithm to figure out which CPU to add, and by extension if any
CPU needs to be hotplugged, is in the function that adds the cpus.
Because of that, the command "query-hotpluggable-cpus" is always
called, even when not needed.

In case we are using a version of QEMU older than 2.7 (Sept 2016)
which don't have "query-hotpluggable-cpus", we fallback to using
"cpu-add".

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Replace QEMU's command line short-form boolean option
Anthony PERARD [Tue, 11 May 2021 09:28:04 +0000 (10:28 +0100)]
libxl: Replace QEMU's command line short-form boolean option

Short-form boolean options are deprecated in QEMU 6.0.
Upstream commit that deprecate those: ccd3b3b8112b ("qemu-option: warn
for short-form boolean options").

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agolibxl: Replace deprecated QMP command by "query-cpus-fast"
Anthony PERARD [Tue, 11 May 2021 09:28:03 +0000 (10:28 +0100)]
libxl: Replace deprecated QMP command by "query-cpus-fast"

We use the deprecated QMP command "query-cpus" which is removed in the
QEMU 6.0 release. There's a replacement which is "query-cpus-fast",
and have been available since QEMU 2.12 (April 2018).

This patch try the new command first and when the command isn't
available, it fall back to the deprecated one so libxl still works
with older QEMU versions.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
3 years agoArm: avoid .init.data to be marked as executable
Jan Beulich [Mon, 14 Jun 2021 13:52:36 +0000 (15:52 +0200)]
Arm: avoid .init.data to be marked as executable

This confuses disassemblers, at the very least. Move
.altinstr_replacement to .init.text. The previously redundant ALIGN()
now gets converted to page alignment, such that the hypervisor mapping
won't have this as executable (it'll instead get mapped r/w, which I'm
told is intended to be adjusted at some point).

Note that for the actual patching logic's purposes this part of
.init.text _has_ to live after _einittext (or before _sinittext), or
else branch_insn_requires_update() would produce wrong results.

Also, to have .altinstr_replacement have consistent attributes in the
object files, add "x" to the one instance where it was missing.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
3 years agoxen/arm32: avoid .rodata to be marked as executable
Jan Beulich [Fri, 11 Jun 2021 09:19:15 +0000 (11:19 +0200)]
xen/arm32: avoid .rodata to be marked as executable

The section .proc.info lives in .rodata as it doesn't contain any
executable code. However, the section is still marked as executable
as the consequence .rodata will also be marked executable.

Xen doesn't use the ELF permissions to decide the page-table mapping
permission. However, this will confuse disassemblers.

'#execinstr' is now removed on all the pushsection dealing with
.proc.info

Signed-off-by: Jan Beulich <jbeulich@suse.com>
[julieng: Rework the commit message]
Acked-by: Julien Grall <jgrall@amazon.com>
3 years agoMAINTAINERS: add myself as tools/libs reviewer
Juergen Gross [Mon, 14 Jun 2021 12:40:19 +0000 (14:40 +0200)]
MAINTAINERS: add myself as tools/libs reviewer

I have touched most of the Xen libraries in the past, and there is a
clear lack of reviewer band width in the tools area.

Add myself as a tools/libs reviewer for that reason.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
3 years agorevert "tools/libs/guest: fix max_pfn setting in map_p2m()"
Juergen Gross [Mon, 14 Jun 2021 12:39:52 +0000 (14:39 +0200)]
revert "tools/libs/guest: fix max_pfn setting in map_p2m()"

The reasoning for commit 7bd8989ab77b6a ("tools/libs/guest: fix max_pfn
setting in map_p2m()") was wrong.

The max_pfn field in shared_info is misnamed, it has the semantics of
num_pfns, which is hidden at least partially in Linux, as the kernel is
(wrongly) treating it like the highest used pfn in some places.

So revert above commit.

Fixes: 7bd8989ab77b6a ("tools/libs/guest: fix max_pfn setting in map_p2m()")
Signed-off-by: Juergen Gross <jgross@suse.com>
3 years agoxen/grant-table: Simplify the update to the per-vCPU maptrack freelist
Julien Grall [Mon, 14 Jun 2021 10:08:30 +0000 (11:08 +0100)]
xen/grant-table: Simplify the update to the per-vCPU maptrack freelist

Since XSA-228 (commit 02cbeeb62075 "gnttab: split maptrack lock
to make it fulfill its purpose again"), v->maptrack_head,
v->maptrack_tail and the content of the freelist are accessed with
the lock v->maptrack_freelist_lock held.

Therefore it is not necessary to update the fields using cmpxchg()
and also read them atomically.

Note that there are two cases where v->maptrack_tail is accessed without
the lock. They both happen in get_maptrack_handle() when initializing
the free list of the current vCPU. Therefore there is no possible race.

The code is now reworked to remove any use of cmpxch() and read_atomic()
when accessing the fields v->maptrack_{head, tail} as wel as the
freelist.

Take the opportunity to add a comment on top of the lock definition
and explain what it protects.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agoArm32: MSR to SPSR needs qualification
Jan Beulich [Fri, 11 Jun 2021 13:04:24 +0000 (15:04 +0200)]
Arm32: MSR to SPSR needs qualification

The Arm ARM's description of MSR (ARM DDI 0406C.d section B9.3.12)
doesn't even allow for plain "SPSR" here, and while gas accepts this, it
takes it to mean SPSR_cf. Yet surely all of SPSR wants updating on this
path, not just the lowest and highest 8 bits.

Fixes: dfcffb128be4 ("xen/arm32: SPSR_hyp/SPSR")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
3 years agotools/libs/store: cleanup libxenstore interface
Juergen Gross [Wed, 12 May 2021 14:48:32 +0000 (16:48 +0200)]
tools/libs/store: cleanup libxenstore interface

There are some internals in the libxenstore interface which should be
removed.

Move those functions into xs_lib.c and the related definitions into
xs_lib.h. Remove the functions from the mapfile. Add xs_lib.o to
xenstore_client as some of the internal functions are needed there.

Bump the libxenstore version to 4.0 as the change is incompatible.
Note that the removed functions should not result in any problem as
they ought to be used by xenstored or xenstore_client only.

Avoid an enum as part of a structure as the size of an enum is
compiler implementation dependent.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
3 years agox86: please Clang in arch_set_info_guest()
Jan Beulich [Thu, 10 Jun 2021 14:56:24 +0000 (16:56 +0200)]
x86: please Clang in arch_set_info_guest()

Clang 10 reports

domain.c:1328:10: error: variable 'cr3_mfn' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
    if ( !compat )
         ^~~~~~~
domain.c:1334:34: note: uninitialized use occurs here
    cr3_page = get_page_from_mfn(cr3_mfn, d);
                                 ^~~~~~~
domain.c:1328:5: note: remove the 'if' if its condition is always true
    if ( !compat )
    ^~~~~~~~~~~~~~
domain.c:1042:18: note: initialize the variable 'cr3_mfn' to silence this warning
    mfn_t cr3_mfn;
                 ^
                  = 0
domain.c:1189:14: error: variable 'fail' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
        if ( !compat )
             ^~~~~~~
domain.c:1211:9: note: uninitialized use occurs here
        fail |= v->arch.pv.gdt_ents != c(gdt_ents);
        ^~~~
domain.c:1189:9: note: remove the 'if' if its condition is always true
        if ( !compat )
        ^~~~~~~~~~~~~~
domain.c:1187:18: note: initialize the variable 'fail' to silence this warning
        bool fail;
                 ^
                  = false

despite this being a build with -O2 in effect, and despite "compat"
being constant "false" when CONFIG_COMPAT (and hence CONFIG_PV32) is not
defined, as it gets set at the top of the function from the result of
is_pv_32bit_domain().

Re-arrange the two "offending" if()s such that when COMPAT=n the
respective variables will be seen as unconditionally initialized. The
original aim was to have the !compat cases first, though.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agoxen/arm32: SPSR_hyp/SPSR
Stefano Stabellini [Wed, 9 Jun 2021 17:37:59 +0000 (10:37 -0700)]
xen/arm32: SPSR_hyp/SPSR

SPSR_hyp is not meant to be accessed from Hyp mode (EL2); accesses
trigger UNPREDICTABLE behaviour. Xen should read/write SPSR instead.
See: ARM DDI 0487D.b page G8-5993.

This fixes booting Xen/arm32 on QEMU.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
3 years agox86/tsx: Cope with TSX deprecation on SKL/KBL/CFL/WHL
Andrew Cooper [Wed, 16 Sep 2020 15:15:52 +0000 (16:15 +0100)]
x86/tsx: Cope with TSX deprecation on SKL/KBL/CFL/WHL

The June 2021 microcode is formally de-featuring TSX on the older Skylake
client CPUs.  The workaround from the March 2019 microcode is being dropped,
and replaced with additions to MSR_TSX_FORCE_ABORT to hide the HLE/RTM CPUID
bits.

With this microcode in place, TSX is disabled by default on these CPUs.
Backwards compatibility is provided in the same way as for TAA - RTM force
aborts, rather than suffering #UD, and the CPUID bits can be hidden to recover
performance.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agoxen: add files needed for minimal riscv build
Connor Davis [Wed, 9 Jun 2021 10:45:38 +0000 (12:45 +0200)]
xen: add files needed for minimal riscv build

Add arch-specific makefiles and configs needed to build for
riscv. Also add a minimal head.S that is a simple infinite loop.
head.o can be built with

$ make XEN_TARGET_ARCH=riscv64 SUBSYSTEMS=xen -C xen tiny64_defconfig
$ make XEN_TARGET_ARCH=riscv64 SUBSYSTEMS=xen -C xen TARGET=riscv64/head.o

No other TARGET is supported at the moment.

Signed-off-by: Connor Davis <connojdavis@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Acked-by: Bobby Eshleman <bobbyeshleman@gmail.com>
3 years agoxen/char: default HAS_NS16550 to y only for X86 and ARM
Connor Davis [Wed, 9 Jun 2021 10:43:45 +0000 (12:43 +0200)]
xen/char: default HAS_NS16550 to y only for X86 and ARM

Defaulting to yes only for X86 and ARM reduces the requirements
for a minimal build when porting new architectures.

Signed-off-by: Connor Davis <connojdavis@gmail.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
3 years agoMAINTAINERS: adjust x86/mm/shadow maintainers
Tim Deegan [Wed, 9 Jun 2021 10:43:25 +0000 (12:43 +0200)]
MAINTAINERS: adjust x86/mm/shadow maintainers

Better reflect reality: Andrew and Jan are active maintainers
and I review patches.  Keep myself as a reviewer so I can help
with historical context &c.

Signed-off-by: Tim Deegan <tim@xen.org>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agoAMD/IOMMU: drop command completion timeout
Jan Beulich [Tue, 8 Jun 2021 17:29:42 +0000 (18:29 +0100)]
AMD/IOMMU: drop command completion timeout

First and foremost - such timeouts were not signaled to callers, making
them believe they're fine to e.g. free previously unmapped pages.

Mirror VT-d's behavior: A fixed number of loop iterations is not a
suitable way to detect timeouts in an environment (CPU and bus speeds)
independent manner anyway. Furthermore, leaving an in-progress operation
pending when it appears to take too long is problematic: If a command
completed later, the signaling of its completion may instead be
understood to signal a subsequently started command's completion.

Log excessively long processing times (with a progressive threshold) to
have some indication of problems in this area. Allow callers to specify
a non-default timeout bias for this logging, using the same values as
VT-d does, which in particular means a (by default) much larger value
for device IO TLB invalidation.

This is part of XSA-373 / CVE-2021-28692.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
3 years agoAMD/IOMMU: wait for command slot to be available
Jan Beulich [Tue, 8 Jun 2021 17:29:40 +0000 (18:29 +0100)]
AMD/IOMMU: wait for command slot to be available

No caller cared about send_iommu_command() indicating unavailability of
a slot. Hence if a sufficient number prior commands timed out, we did
blindly assume that the requested command was submitted to the IOMMU
when really it wasn't. This could mean both a hanging system (waiting
for a command to complete that was never seen by the IOMMU) or blindly
propagating success back to callers, making them believe they're fine
to e.g. free previously unmapped pages.

Fold the three involved functions into one, add spin waiting for an
available slot along the lines of VT-d's qinval_next_index(), and as a
consequence drop all error indicator return types/values.

This is part of XSA-373 / CVE-2021-28692.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
3 years agox86/spec-ctrl: Mitigate TAA after S3 resume
Andrew Cooper [Thu, 20 May 2021 00:21:39 +0000 (01:21 +0100)]
x86/spec-ctrl: Mitigate TAA after S3 resume

The user chosen setting for MSR_TSX_CTRL needs restoring after S3.

All APs get the correct setting via start_secondary(), but the BSP was missed
out.

This is XSA-377 / CVE-2021-28690.

Fixes: 8c4330818f6 ("x86/spec-ctrl: Mitigate the TSX Asynchronous Abort sidechannel")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/spec-ctrl: Protect against Speculative Code Store Bypass
Andrew Cooper [Thu, 11 Mar 2021 14:39:11 +0000 (14:39 +0000)]
x86/spec-ctrl: Protect against Speculative Code Store Bypass

Modern x86 processors have far-better-than-architecturally-guaranteed self
modifying code detection.  Typically, when a write hits an instruction in
flight, a Machine Clear occurs to flush stale content in the frontend and
backend.

For self modifying code, before a write which hits an instruction in flight
retires, the frontend can speculatively decode and execute the old instruction
stream.  Speculation of this form can suffer from type confusion in registers,
and potentially leak data.

Furthermore, updates are typically byte-wise, rather than atomic.  Depending
on timing, speculation can race ahead multiple times between individual
writes, and execute the transiently-malformed instruction stream.

Xen has stubs which are used in certain cases for emulation purposes.  Inhibit
speculation between updating the stub and executing it.

This is XSA-375 / CVE-2021-0089.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agoVT-d: eliminate flush related timeouts
Jan Beulich [Tue, 8 Jun 2021 16:38:55 +0000 (17:38 +0100)]
VT-d: eliminate flush related timeouts

Leaving an in-progress operation pending when it appears to take too
long is problematic: If e.g. a QI command completed later, the write to
the "poll slot" may instead be understood to signal a subsequently
started command's completion. Also our accounting of the timeout period
was actually wrong: We included the time it took for the command to
actually make it to the front of the queue, which could be heavily
affected by guests other than the one for which the flush is being
performed.

Do away with all timeout detection on all flush related code paths.
Log excessively long processing times (with a progressive threshold) to
have some indication of problems in this area.

Additionally log (once) if qinval_next_index() didn't immediately find
an available slot. Together with the earlier change sizing the queue(s)
dynamically, we should now have a guarantee that with our fully
synchronous model any demand for slots can actually be satisfied.

This is part of XSA-373 / CVE-2021-28692.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
3 years agoAMD/IOMMU: size command buffer dynamically
Jan Beulich [Tue, 8 Jun 2021 16:38:55 +0000 (17:38 +0100)]
AMD/IOMMU: size command buffer dynamically

With the present synchronous model, we need two slots for every
operation (the operation itself and a wait command).  There can be one
such pair of commands pending per CPU. To ensure that under all normal
circumstances a slot is always available when one is requested, size the
command ring according to the number of present CPUs.

This is part of XSA-373 / CVE-2021-28692.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
3 years agoVT-d: size qinval queue dynamically
Jan Beulich [Tue, 8 Jun 2021 16:38:55 +0000 (17:38 +0100)]
VT-d: size qinval queue dynamically

With the present synchronous model, we need two slots for every
operation (the operation itself and a wait descriptor).  There can be
one such pair of requests pending per CPU. To ensure that under all
normal circumstances a slot is always available when one is requested,
size the queue ring according to the number of present CPUs.

This is part of XSA-373 / CVE-2021-28692.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
3 years agoxen/arm: Boot modules should always be scrubbed if bootscrub={on, idle}
Julien Grall [Sat, 17 Apr 2021 16:38:28 +0000 (17:38 +0100)]
xen/arm: Boot modules should always be scrubbed if bootscrub={on, idle}

The function to initialize the pages (see init_heap_pages()) will request
scrub when the admin request idle bootscrub (default) and state ==
SYS_STATE_active. When bootscrub=on, Xen will scrub any free pages in
heap_init_late().

Currently, the boot modules (e.g. kernels, initramfs) will be discarded/
freed after heap_init_late() is called and system_state switched to
SYS_STATE_active. This means the pages associated with the boot modules
will not get scrubbed before getting re-purposed.

If the memory is assigned to an untrusted domU, it may be able to
retrieve secrets from the modules.

This is part of XSA-372 / CVE-2021-28693.

Fixes: 1774e9b1df27 ("xen/arm: introduce create_domUs")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
3 years agoxen/arm: Create dom0less domUs earlier
Julien Grall [Mon, 17 May 2021 16:47:13 +0000 (17:47 +0100)]
xen/arm: Create dom0less domUs earlier

In a follow-up patch we will need to unallocate the boot modules
before heap_init_late() is called.

The modules will contain the domUs kernel and initramfs. Therefore Xen
will need to create extra domUs (used by dom0less) before heap_init_late().

This has two consequences on dom0less:
    1) Domains will not be unpaused as soon as they are created but
    once all have been created. However, Xen doesn't guarantee an order
    to unpause, so this is not something one could rely on.

    2) The memory allocated for a domU will not be scrubbed anymore when an
    admin select bootscrub=on. This is not something we advertised, but if
    this is a concern we can introduce either force scrub for all domUs or
    a per-domain flag in the DT. The behavior for bootscrub=off and
    bootscrub=idle (default) has not changed.

This is part of XSA-372 / CVE-2021-28693.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
3 years agox86/cpuid: Half revert "x86/cpuid: Drop special_features[]"
Andrew Cooper [Tue, 8 Jun 2021 16:13:59 +0000 (17:13 +0100)]
x86/cpuid: Half revert "x86/cpuid: Drop special_features[]"

xen-cpuid does print out the list of special features, and this is helpful to
keep.

Fixes: ba6950fb070 ("x86/cpuid: Drop special_features[]")
Reported-by: Jan Beulich <JBeulich@suse.com>
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
3 years agoevtchn: type adjustments
Jan Beulich [Tue, 8 Jun 2021 12:47:47 +0000 (14:47 +0200)]
evtchn: type adjustments

First of all avoid "long" when "int" suffices, i.e. in particular when
merely conveying error codes. 32-bit values are slightly cheaper to
deal with on x86, and their processing is at least no more expensive on
Arm. Where possible use evtchn_port_t for port numbers and unsigned int
for other unsigned quantities in adjacent code. In evtchn_set_priority()
eliminate a local variable altogether instead of changing its type.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
3 years agoevtchn: add helper for port_is_valid() + evtchn_from_port()
Jan Beulich [Tue, 8 Jun 2021 12:47:14 +0000 (14:47 +0200)]
evtchn: add helper for port_is_valid() + evtchn_from_port()

The combination is pretty common, so adding a simple local helper seems
worthwhile. Make it const- and type-correct, in turn requiring the
two called function to also be const-correct (and at this occasion also
make them type-correct).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
3 years agoevtchn: slightly defer lock acquire where possible
Jan Beulich [Tue, 8 Jun 2021 12:46:06 +0000 (14:46 +0200)]
evtchn: slightly defer lock acquire where possible

port_is_valid() and evtchn_from_port() are fine to use without holding
any locks. Accordingly acquire the per-domain lock slightly later in
evtchn_close() and evtchn_bind_vcpu(). Especially for the use by the
former (but there are pre-existing uses) add a comment about
port_is_valid()'s guarantees.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Julien Grall <julien@xen.org>
3 years agotools/firmware/ovmf: Use OvmfXen platform file is exist
Anthony PERARD [Tue, 1 Jun 2021 10:28:03 +0000 (11:28 +0100)]
tools/firmware/ovmf: Use OvmfXen platform file is exist

A platform introduced in EDK II named OvmfXen is now the one to use for
Xen instead of OvmfX64. It comes with PVH support.

Also, the Xen support in OvmfX64 is deprecated,
    "deprecation notice: *dynamic* multi-VMM (QEMU vs. Xen) support in OvmfPkg"
    https://edk2.groups.io/g/devel/message/75498

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
3 years agotools/libs/guest: fix save and restore of pv domains after 32-bit de-support
Juergen Gross [Mon, 7 Jun 2021 13:00:05 +0000 (15:00 +0200)]
tools/libs/guest: fix save and restore of pv domains after 32-bit de-support

After 32-bit PV-guests have been security de-supported when not running
under PV-shim, the hypervisor will no longer be configured to support
those domains per default when not being built as PV-shim.

Unfortunately libxenguest will fail saving or restoring a PV domain
due to this restriction, as it is trying to get the compat MFN list
even for 64 bit guests.

Fix that by obtaining the compat MFN list only for 32-bit PV guests.

Fixes: 1a0f2fe2297d122a08fe ("SUPPORT.md: Un-shimmed 32-bit PV guests are no longer supported")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
3 years agox86/cpuid: Drop special_features[]
Andrew Cooper [Mon, 7 Jun 2021 12:38:53 +0000 (13:38 +0100)]
x86/cpuid: Drop special_features[]

While the ! annotation is useful to indicate that something special is
happening, an array of bits is not.  Drop it, to prevent mistakes.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/cpuid: Fix HLE and RTM handling (again)
Andrew Cooper [Mon, 7 Jun 2021 12:25:09 +0000 (13:25 +0100)]
x86/cpuid: Fix HLE and RTM handling (again)

For reasons which are my fault, but I don't recall why, the
FDP_EXCP_ONLY/NO_FPU_SEL adjustment uses the whole special_features[] array
element, not the two relevant bits.

HLE and RTM were recently added to the list of special features, causing them
to be always set in guest view, irrespective of the toolstacks choice on the
matter.

Rewrite the logic to refer to the features specifically, rather than relying
on the contents of the special_features[] array.

Fixes: 8fe24090d9 ("x86/cpuid: Rework HLE and RTM handling")
Reported-by: Edwin Török <edvin.torok@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agodocs: release-technician-checklist: update to leaf tree version pinning
Jan Beulich [Mon, 7 Jun 2021 13:40:55 +0000 (15:40 +0200)]
docs: release-technician-checklist: update to leaf tree version pinning

Our releases look to flip-flop between keeping or discarding the date
and title of the referenced qemu-trad commit. I think with the hash
replaced by a tag, the commit's date and title would better also be
purged.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
3 years agoxen: credit2: fix per-entity load tracking when continuing running
Dario Faggioli [Fri, 19 Mar 2021 12:14:17 +0000 (12:14 +0000)]
xen: credit2: fix per-entity load tracking when continuing running

If we schedule, and the current vCPU continues to run, its statistical
load is not properly updated, resulting in something like this, even if
all the 8 vCPUs are 100% busy:

(XEN) Runqueue 0:
(XEN) [...]
(XEN)   aveload            = 2097152 (~800%)
(XEN) [...]
(XEN)   Domain: 0 w 256 c 0 v 8
(XEN)     1: [0.0] flags=2 cpu=4 credit=9996885 [w=256] load=35 (~0%)
(XEN)     2: [0.1] flags=2 cpu=2 credit=9993725 [w=256] load=796 (~0%)
(XEN)     3: [0.2] flags=2 cpu=1 credit=9995885 [w=256] load=883 (~0%)
(XEN)     4: [0.3] flags=2 cpu=5 credit=9998833 [w=256] load=487 (~0%)
(XEN)     5: [0.4] flags=2 cpu=6 credit=9998942 [w=256] load=1595 (~0%)
(XEN)     6: [0.5] flags=2 cpu=0 credit=9994669 [w=256] load=22 (~0%)
(XEN)     7: [0.6] flags=2 cpu=7 credit=9997706 [w=256] load=0 (~0%)
(XEN)     8: [0.7] flags=2 cpu=3 credit=9992440 [w=256] load=0 (~0%)

As we can see, the average load of the runqueue as a whole is, instead,
computed properly.

This issue would, in theory, potentially affect Credit2 load balancing
logic. In practice, however, the problem only manifests (at least with
these characteristics) when there is only 1 runqueue active in the
cpupool, which also means there is no need to do any load-balancing.

Hence its real impact is pretty much limited to wrong per-vCPU load
percentages, when looking at the output of the 'r' debug-key.

With this patch, the load is updated and displayed correctly:

(XEN) Runqueue 0:
(XEN) [...]
(XEN)   aveload            = 2097152 (~800%)
(XEN) [...]
(XEN) Domain info:
(XEN)   Domain: 0 w 256 c 0 v 8
(XEN)     1: [0.0] flags=2 cpu=4 credit=9995584 [w=256] load=262144 (~100%)
(XEN)     2: [0.1] flags=2 cpu=6 credit=9992992 [w=256] load=262144 (~100%)
(XEN)     3: [0.2] flags=2 cpu=3 credit=9998918 [w=256] load=262118 (~99%)
(XEN)     4: [0.3] flags=2 cpu=5 credit=9996867 [w=256] load=262144 (~100%)
(XEN)     5: [0.4] flags=2 cpu=1 credit=9998912 [w=256] load=262144 (~100%)
(XEN)     6: [0.5] flags=2 cpu=2 credit=9997842 [w=256] load=262144 (~100%)
(XEN)     7: [0.6] flags=2 cpu=7 credit=9994623 [w=256] load=262144 (~100%)
(XEN)     8: [0.7] flags=2 cpu=0 credit=9991815 [w=256] load=262144 (~100%)

Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agocredit2: make sure we pick a runnable unit from the runq if there is one
Dario Faggioli [Fri, 28 May 2021 15:12:48 +0000 (17:12 +0200)]
credit2: make sure we pick a runnable unit from the runq if there is one

A !runnable unit (temporarily) present in the runq may cause us to
stop scanning the runq itself too early. Of course, we don't run any
non-runnable vCPUs, but we end the scan and we fallback to picking
the idle unit. In other word, this prevent us to find there and pick
the actual unit that we're meant to start running (which might be
further ahead in the runq).

Depending on the vCPU pinning configuration, this may lead to such
unit to be stuck in the runq for long time, causing malfunctioning
inside the guest.

Fix this by checking runnable/non-runnable status up-front, in the runq
scanning function.

Reported-by: Michał Leszczyński <michal.leszczynski@cert.pl>
Reported-by: Dion Kant <g.w.kant@hunenet.nl>
Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
3 years agotools/libs/guest: make some definitions private to libxenguest
Juergen Gross [Fri, 4 Jun 2021 06:02:14 +0000 (08:02 +0200)]
tools/libs/guest: make some definitions private to libxenguest

There are some definitions which are used in libxenguest only now.
Move them from libxenctrl over to libxenguest.

Remove an unused macro.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
3 years agotools/libs: move xc_core* from libxenctrl to libxenguest
Juergen Gross [Fri, 4 Jun 2021 06:02:13 +0000 (08:02 +0200)]
tools/libs: move xc_core* from libxenctrl to libxenguest

The functionality in xc_core* should be part of libxenguest instead
of libxenctrl. Users are already either in libxenguest, or in xl.
There is one single exception: xc_core_arch_auto_translated_physmap()
is being used by xc_domain_memory_mapping(), which is used by qemu.
So leave the xc_core_arch_auto_translated_physmap() functionality in
libxenctrl.

This will make it easier to merge common functionality of xc_core*
and xg_sr_save*.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
3 years agotools/libs: move xc_resume.c to libxenguest
Juergen Gross [Fri, 4 Jun 2021 06:02:12 +0000 (08:02 +0200)]
tools/libs: move xc_resume.c to libxenguest

The guest suspend functionality is already part of libxenguest. Move
the resume functionality from libxenctrl to libxenguest, too.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
3 years agotools/libs/ctrl: use common p2m mapping code in xc_domain_resume_any()
Juergen Gross [Fri, 4 Jun 2021 06:02:11 +0000 (08:02 +0200)]
tools/libs/ctrl: use common p2m mapping code in xc_domain_resume_any()

Instead of open coding the mapping of the p2m list use the already
existing xc_core_arch_map_p2m() call, especially as the current code
does not support guests with the linear p2m map. It should be noted
that this code is needed for colo/remus only.

Switching to xc_core_arch_map_p2m() drops the need to bail out for
bitness of tool stack and guest differing.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
3 years agotools/libs/ctrl: fix xc_core_arch_map_p2m() to support linear p2m table
Juergen Gross [Fri, 4 Jun 2021 06:02:10 +0000 (08:02 +0200)]
tools/libs/ctrl: fix xc_core_arch_map_p2m() to support linear p2m table

The core of a pv linux guest produced via "xl dump-core" is nor usable
as since kernel 4.14 only the linear p2m table is kept if Xen indicates
it is supporting that. Unfortunately xc_core_arch_map_p2m() is still
supporting the 3-level p2m tree only.

Fix that by copying the functionality of map_p2m() from libxenguest to
libxenctrl.

Additionally the mapped p2m isn't of a fixed length now, so the
interface to the mapping functions needs to be adapted. In order not to
add even more parameters, expand struct domain_info_context and use a
pointer to that as a parameter.

Fixes: dc6d60937121 ("libxc: set flag for support of linear p2m list in domain builder")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
3 years agotools/libs/guest: fix max_pfn setting in map_p2m()
Juergen Gross [Fri, 4 Jun 2021 06:02:09 +0000 (08:02 +0200)]
tools/libs/guest: fix max_pfn setting in map_p2m()

When setting the highest pfn used in the guest, don't subtract 1 from
the value read from the shared_info data. The value read already is
the correct pfn.

Fixes: 91e204d37f449 ("libxc: try to find last used pfn when migrating")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
3 years agoSUPPORT.md: Un-shimmed 32-bit PV guests are no longer supported
George Dunlap [Thu, 6 May 2021 12:38:02 +0000 (13:38 +0100)]
SUPPORT.md: Un-shimmed 32-bit PV guests are no longer supported

The support status of 32-bit guests doesn't seem particularly useful.

With it changed to fully unsupported outside of PV-shim, adjust the PV32
Kconfig default accordingly.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
3 years agoxen/page_alloc: Remove dead code in alloc_domheap_pages()
Julien Grall [Mon, 22 Feb 2021 12:01:18 +0000 (12:01 +0000)]
xen/page_alloc: Remove dead code in alloc_domheap_pages()

Since commit 1aac966e24e9 "xen: support RAM at addresses 0 and 4096",
bits_to_zone() will never return 0 and it is expected that we have
minimum 2 zones.

Therefore the check in alloc_domheap_pages() is unnecessary and can
be removed. However, for sanity, it is replaced with an ASSERT().

Also take the opportunity to switch from min_t() to min() as
bits_to_zone() cannot return a negative value. The macro is tweaked
to make it clearer.

This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/mtrr: remove stale function prototype
Roger Pau Monné [Mon, 31 May 2021 10:47:12 +0000 (12:47 +0200)]
x86/mtrr: remove stale function prototype

Fixes: 1c84d04673 ('VMX: remove the problematic set_uc_mode logic')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
3 years agox86/tboot: adjust UUID check
Jan Beulich [Mon, 31 May 2021 10:46:48 +0000 (12:46 +0200)]
x86/tboot: adjust UUID check

Replace a bogus cast, move the static variable into the only function
using it, and add __initconst. While there, also remove a pointless NULL
check.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Lukasz Hawrylko <lukasz.hawrylko@linux.intel.com>
3 years agox86/tboot: include all valid frame table entries in S3 integrity check
Jan Beulich [Mon, 31 May 2021 10:45:51 +0000 (12:45 +0200)]
x86/tboot: include all valid frame table entries in S3 integrity check

The difference of two pdx_to_page() return values is a number of pages,
not the number of bytes covered by the corresponding frame table entries.

Fixes: 3cb68d2b59ab ("tboot: fix S3 issue for Intel Trusted Execution Technology.")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Lukasz Hawrylko <lukasz.hawrylko@linux.intel.com>