While the lack of proper dependency tracking of #include-d files is
wider than just the libs/ subtree, dealing with the problem universally
there or in tools/Rules.mk is too much of a risk at this point in the
release cycle. Add the missing inclusion of $(DEPS_INCLUDE) only in the
specific Makefile-s, after having checked that their prior Makefile-s
had such includes.
Interestingly the $(DEPS_RM) use is present in tools/libs/libs.mk's
clean target, so doesn't need taking care of in individual Makefile-s.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Release-acked-by: Ian Jackson <iwj@xenproject.org>
There are no users left, xenpaging has its own variant.
The last user was removed with commit 11d0044a16
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Wei Liu <wl@xen.org>
Allocate enough memory so that the returned pointer can be safely
accessed as an array of unsigned long.
The actual bitmap size in units of bytes, as returned by bitmap_size,
remains unchanged.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Wei Liu <wl@xen.org>
A guest with memory < maxmem often can't be dumped via xl dump-core
without an error message today:
xc: info: exceeded nr_pages (262144) losing pages
In case the last page of the guest isn't allocated the loop in
xc_domain_dumpcore_via_callback() will always spit out this message,
as the number of already dumped pages is tested before the next page
is checked to be valid.
The guest's p2m_size might be lower than expected, so this should be
tested in order to avoid reading past the end of it.
The guest might use high bits in p2m entries to flag special cases like
foreign mappings. Entries with an MFN larger than the highest MFN of
the host should be skipped.
Signed-off-by: Juergen Gross <jgross@suse.com>
Instead of each library having an own include directory move the
official headers to tools/include instead. This will drop the need to
link those headers to tools/include and there is no need any longer
to have library-specific include paths when building Xen.
While at it remove setting of the unused variable
PKG_CONFIG_CFLAGS_LOCAL in libs/*/Makefile.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Tested-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Today xenctrl_dom.h is part of libxenctrl as it is included by
xc_private.c. This seems not to be needed, so merge xenctrl_dom.h into
xenguest.h where its contents really should be.
Replace all #includes of xenctrl_dom.h by xenguest.h ones or drop them
if xenguest.h is already included.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
MFENCE is overly heavyweight for SMP semantics on WB memory, because it also
orders weaker cached writes, and flushes the WC buffers.
This technique was used as an optimisation in Java[1], and later adopted by
Linux[2] where it was measured to have a 60% performance improvement in VirtIO
benchmarks.
The stack is used because it is hot in the L1 cache, and a -4 offset is used
to avoid creating a false data dependency on live data.
For 64bit userspace, the Red Zone needs to be considered. Use -32 to allow
for a reasonable quantity of Red Zone data, but still have a 50% chance of
hitting the same cache line as %rsp.
Fix up the 32 bit definitions in HVMLoader and libxc to avoid a false data
dependency.
[1] https://shipilev.net/blog/2014/on-the-fence-with-dependencies/
[2] https://git.kernel.org/torvalds/c/450cbdd0125cfa5d7bbf9e2a6b6961cc48d29730
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Nested Virt is the final special case in legacy CPUID handling. Pass the
(poorly named) nested_hvm setting down into xc_cpuid_apply_policy() to break
the semantic dependency on HVM_PARAM_NESTEDHVM.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
If the bitmap is used to represent domU pages, the amount of memory is
limited to 8TB due to the 32bit value. Adjust the code to use 64bit
values as input. All callers already use some form of 64bit as input,
so no further adjustment is required.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
The caller of writev_exact should be notified about malloc errors
when dealing with partial writes.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
It is conceptually wrong for this information to exist in the hypervisor in
the first place. Only the toolstack is capable of correctly reasoning about
the non-migrateability of guests.
This hypercall has only ever existed to control the visibility of the
Invariant TSC flag to the guest. Now that we have properly disentanged that
and moved ITSC into the guests CPUID policy, delete this hypercall.
Furthermore, this fixes a corner case where Xen would override the toolstacks
choice of ITSC for a xenstore stubdomain. That said, init-xenstore-domain
doesn't currently ask for ITSC, and MiniOS doesn't know what ITSC is either,
so nothing actually changes in practice.
Bump the DOMCTL_INTERFACE_VERSION for 4.15
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
ITSC being visible to the guest is currently implicit with the toolstack
unconditionally asking for it, and Xen clipping it based on the vTSC and/or
XEN_DOMCTL_disable_migrate settings.
This is problematic for several reasons.
First, the implicit vTSC behaviour manifests as a real bug on migration to a
host with a different frequency, with ITSC but without TSC scaling
capabilities, whereby the ITSC feature becomes advertised to the guest. ITSC
will disappear again if the guest migrates to server with the same frequency
as the original, or to one with TSC scaling support.
Secondly, disallowing ITSC unless the guest doesn't migrate is conceptually
wrong. It is common to have migration pools of identical hardware, at which
point the TSC frequency is nominally the same, and more modern hardware has
TSC scaling support anyway. In both cases, it is safe to advertise ITSC and
migrate the guest.
Remove all implicit logic in Xen, and make ITSC part of the max CPUID policies
for guests. Plumb an itsc parameter into xc_cpuid_apply_policy() and have
libxl__cpuid_legacy() fill in the two cases where it can reasonably expect
ITSC to be safe for the guest to see. This retains the current side effect of
enabling ITSC if the guest is marked as nomigrate.
This is a behaviour change for TSC_MODE_NATIVE, where the ITSC will now
reliably not appear, and for the case where the user explicitly requests ITSC,
in which case it will appear even if the guest isn't marked as nomigrate.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <Ian.Jackson@citrix.com>
Today tools/libxc needs to be built after tools/libs as libxenctrl is
depending on some libraries in tools/libs. This in turn blocks moving
other libraries depending on libxenctrl below tools/libs.
So carve out libxenctrl from tools/libxc and move it into
tools/libs/ctrl.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> (stubdom parts)
Acked-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> (python parts)
Acked-by: Wei Liu <wl@xen.org>
Jan Beulich
Olaf Hering
Juergen Gross
Andrew Cooper