COPYING file:
The motivation of this change is to make it easier for new
contributors to conduct a license and patent review, WITHOUT
changing any licenses.
- Remove references to BSD-style licenses as we have more
common license exceptions and replace with "other license
stanzas"
- List the most common situations under which code is licensed
under licenses other than GPLv2 (section "Licensing Exceptions")
- List the most common non-GPLv2 licenses that are in use in
this repository based on a recent FOSSology scan (section
"Licensing Exceptions")
- List other license related conventions within the project
to make it easier to conduct a license review.
- Clarify the incoming license as its omission has confused
past contributors (section "Contributions")
CONTRIBUTION file:
The motivation of this file is to make it easier for contributors
to find contribution related resources. Add information on existing
license related conventions to avoid unintentional future licensing
issues. Provide templates for copyright headers for the most commonly
used licenses in this repository.
Signed-off-by: Lars Kurth <lars.kurth@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
This matches hardware behaviour, and prevents erroneous failures when a guest
has SMEP/SMAP active and issues a FEP from userspace.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
There is no need to read the segment information from VMCS/VMCB and cache it,
just to clobber the cached content immediately afterwards.
Write straight into the cache and set the accessed/dirty bits.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
HVM HAP codepaths have space for all segment registers in the seg_reg[]
cache (with x86_seg_none still risking an array overrun), while the shadow
codepaths only have space for the user segments.
Range check the input segment of *_get_seg_reg() against the size of the array
used to cache the results, to avoid overruns in the case that the callers
don't filter their input suitably.
Subsume the is_x86_user_segment(seg) checks from the shadow code, which were
an incomplete attempt at range checking, and are now superceeded. Make
hvm_get_seg_reg() static, as it is not used outside of shadow/common.c
No functional change, but far easier to reason that no overflow is possible.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Jan Beulich <jbeulich@suse.com>
The Force Emulation Prefix is named to follow its PV counterpart for cpuid or
rdtsc, but isn't really an instruction prefix. It behaves as a break-out into
Xen, with the purpose of emulating the next instruction in the current state.
It is important to be able to test legal situations which occur in real
hardware, including instruction which cross certain boundaries, and
instructions starting at 0.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Commit 6ea24e53f1 introduced two problems: It left out a semicolon and
typo-ed the source file name of the EFI map file install command.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Non-debugging message text should be (and is in the cases here, albeit
often only with the addition of an ELF: prefix) distinguishable without
also logging function names.
In the messages touched at once use %#x (or variants thereof) in favor
of 0x%x.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
hvm_get_seg_reg() does not perform a range check on its input segment, calls
hvm_get_segment_register() and writes straight into sh_ctxt->seg_reg[].
x86_seg_none is outside the bounds of sh_ctxt->seg_reg[], and will hit a BUG()
in {vmx,svm}_get_segment_register().
HVM guests running with shadow paging can end up performing a virtual to
linear translation with x86_seg_none. This is used for addresses which are
already linear. However, none of this is a legitimate pagetable update, so
fail the emulation in such a case.
This is XSA-187 / CVE-2016-7094.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Tim Deegan <tim@xen.org>
This reverts most of c/s 0640ffb6 "x86emul: fix rIP handling".
Experimentally, in long mode processors will execute an instruction stream
which crosses the 64bit -1 -> 0 virtual boundary, whether the instruction
boundary is aligned on the virtual boundary, or is misaligned.
In compatibility mode, Intel processors will execute an instruction stream
which crosses the 32bit -1 -> 0 virtual boundary, while AMD processors raise a
segmentation fault. Xen's segmentation behaviour matches AMD.
For 16bit code, hardware does not ever truncated %ip. %eip is always used and
behaves normally as a 32bit register, including in 16bit protected mode
segments, as well as in Real and Unreal mode.
This is XSA-186 / CVE-2016-7093.
Reported-by: Brian Marcotte <marcotte@panix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
L3 entries are special in PAE mode, and hence can't reasonably be used
for setting up recursive (and hence linear) page table mappings. Since
abuse is possible when the guest in fact gets run on 4-level page
tables, this needs to be excluded explicitly.
This is XSA-185 / CVE-2016-7092.
Reported-by: Jérémie Boutoille <jboutoille@ext.quarkslab.com>
Reported-by: "栾尚聪(好风)" <shangcong.lsc@alibaba-inc.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
When doing cross-compilation we should use proper $(OBJDUMP).
Otherwise decompiling say ARM 32 code using x86 objdump
won't help much.
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
You could construct _most_ of the names of the functions
by doing 'nm --defined' but unfortunatly you do not get the
<file> prefix that is added on in Xen . For example:
$ cat xen-syms.symbols |grep do_domain_pause
0xffff82d080104920 t domain.c#do_domain_pause
$ nm --defined xen-syms|grep do_domain_pause
ffff82d080104920 t do_domain_pause
This is normally not an issue, but if one is doing livepatching and
wants during build-time verify that the symbols the livepatch payloads
will patch do correspond to the one the hypervisor has built - this helps a lot.
Note that during runtime one can do:
[root@localhost xen]# cat /proc/xen/xensyms |grep do_domain_pause
ffff82d080104920 t domain.c#do_domain_pause
But one may not want to build and verify a livepatch on the same host.
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Specifically the code that is looking up f->old_addr - which
can be in its own routine instead of having it part of prepare_payload.
No functional change.
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Livepatch expected at some point to be able to print the
build-id during bootup, which it did not. The reason is
that xen_build_init and livepatch_init are both __initcall
type routines. This meant that when livepatch_init called
xen_build_id, it would return -ENODATA as build_id_len was
not setup yet (b/c xen_build_init would be called later).
The original patch fixed this by calling xen_build_init in
livepatch_init which allows us to print the build-id of
the hypervisor.
However the x86 maintainers pointed out that build-id
is independent of Livepatch and in fact should print
regardless whether Livepatch is enabled or not.
Therefore this patch moves the logic of printing the build-id
to version.c.
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It makes more sense for it to be there. However that
means the version.h has now a dependency on <xen/elfstructs.h>
as the Elf_Note is a macro.
The elfstructs.h has a dependency on types.h as well so
we need that. We cannot put that #include <xen/types.h>
in elfstructs.h as that file is used by tools and they
do not have such file.
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It is possible. Especially if the only thing they do is
NOP functions - in which case there is only .livepatch.funcs
sections.
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Consistently consult hvm_cpuid(). With that, BNDCFGS gets better
handled outside of VMX specific code, just like XSS. Don't needlessly
check for MTRR support when the MSR being accessed clearly is not an
MTRR one.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Their VMCS fields aren't tied to the respective base CPU feature flags
but instead to VMX specific ones.
Note that while the VMCS GUEST_BNDCFGS field exists if either of the
two respective features is available, MPX continues to get exposed to
guests only with both features present.
Also add the so far missing handling of
- GUEST_BNDCFGS in construct_vmcs()
- MSR_IA32_BNDCFGS in vmx_msr_{read,write}_intercept()
and mirror the extra correctness checks during MSR write to
vmx_load_msr().
Reported-by: "Rockosov, Dmitry" <dmitry.rockosov@intel.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: "Rockosov, Dmitry" <dmitry.rockosov@intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Use __get_gfn_type_access instead of get_gfn_type_access when checking
the hostp2m entries during altp2m mem_access setting and gfn remapping
to avoid a lock conflict which can make dom0 freeze. During mem_access
setting the hp2m is already locked. For gfn remapping we change the flow
to lock the hp2m before locking the ap2m.
Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com>
Reviewed-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
This doesn't cover all of them, just the ones that I think would most
obviously better be -EINVAL or -EOPNOTSUPP.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
The sole purpose of TEST_COVERAGE macro is to guard the availability of
gcov sysctl. Now we have a proper CONFIG_GCOV, use it.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
The version of gcc (4.9.2) I use put constructors into .init_array*
section(s). Collect those sections into constructor list as well.
Modify both arm and x86 scripts to keep them in sync.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
The highest populated entry in each hypercall table is currently at index 49.
There is no need to extend both to tables to 64 entries.
Range check eax against the hypercall table array size, and use a
BUILD_BUG_ON() to ensure that the hypercall tables don't grow larger than the
args table.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
For the same reason as c/s 33a231e3f "x86/HVM: fold hypercall tables" and
c/s d6d67b047 "x86/pv: Merge the pv hypercall tables", this removes the
risk of accidentally updating only one of the tables.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
For the same reason as c/s 33a231e3f "x86/HVM: fold hypercall tables", this
removes the risk of accidentally updating only one of the tables.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The x86 multicall handling was previously some very hairy inline assembly, and
is hard to follow and maintain.
Replace the existing do_multicall_call() with arch_do_multicall_call(). The
x86 side needs to handle both compat and non-compat calls, so pass the full
multicall state, rather than just the multicall_entry sub-structure.
On the ARM side, alter the prototype to match, but there is no resulting
functional change. On the x86 side, the implementation is now in plain C.
This allows the removal of both asm/multicall.h header files.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Editing (and indeed, finding) the hypercall tables can be tricky, especially
towards the end where .rept's are used to maintain the correct layout.
Move this all into C, and let the compiler do the hard work.
To do this, xen/hypercall.h and asm-x86/hypercall.h need to contain prototypes
for all the hypercalls; some were previously missing. This in turn requires
some shuffling of definitions and includes.
One difference is that NULL function pointers are used instead of
{,compat_}do_ni_hypercall(), which pv_hypercall() handles correctly. All
ni_hypercall() infrastructure is therefore dropped.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
In a similar style to hvm_do_hypercall(). The C version is far easier to
understand and edit than the assembly versions.
There are a few small differences however. The register clobbering values
have changed (to match the HVM side), and in particular clobber the upper
32bits of 64bit arguments. The hypercall and performance counter record are
reordered to increase code sharing between the 32bit and 64bit cases.
The sole callers of __trace_hypercall_entry() were the assembly code. Given
the new C layout, it is more convenient to fold __trace_hypercall_entry() into
pv_hypercall(), and call __trace_hypercall() directly.
Finally, pv_hypercall() will treat a NULL hypercall function pointer as
-ENOSYS, allowing further cleanup.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Editing (and indeed, finding) the hypercall args tables can be tricky,
especially towards the end where .rept's are used to maintain the correct
layout.
Move this all into C, and let the compiler do the hard work. As 0 is the
default value, drop all explicit 0's.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
set_segment_base is the only hypercall exists in only one of the two modes
guests might run in; all other hypercalls are either implemented, or
unimplemented in both modes.
Remove this split, by allowing do_set_segment_base() to be called in the
compat hypercall path. This change will simplify the verification logic in a
later change.
No behavioural change from a guests point of view.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <JBeulich@suse.com>
It will be reused for PV hypercalls in subsequent changes.
* Rename hvm_hypercall_t to hypercall_fn_t
* Introduce hypercall_table_t
Finally, rework the #includes for hypercall.h so it may be included in
isolation.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <JBeulich@suse.com>
Add a parameter to xencommons configuration file for specifying the
maximum memory size of the xenstore domain.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Add a parameter to specify the maximum memory size of the xenstore
domain. In case the xenstore domain supports ballooning it will be
capable to adjust its own size according to its memory needs.
The maximum memory size can be specified as an absolute value in
MiB, as a fraction of the host's memory, or as a combination of
both (the maximum of the absolute and the fraction value):
--maxmem <m> maxmem is <m> MiB
--maxmem <a>/<b> maxmem is hostmem * a / b
--maxmem <m>:<a>/<b> maxmem is max(<m> MiB, hostmem * a / b)
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Blktap2 is effectively dead code for a few years.
Notable changes in this patch:
0. Unhook blktap2 from build system
1. Now libxl no longer supports TAP disk backend, appropriate assertions
are added and some code paths now return ERROR_FAIL
2. Tap is no longer a supported backend in doc
3. Remove relevant entries in MAINTAINERS
A patch to actually remove blktap2 directory will come later.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: George Dunlap <George.Dunlap@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Another place where we should try to behave sufficiently close to how
real hardware does; see the code comments.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
The two functions monitor_traps and mem_access_send_req duplicate some of the
same functionality. The mem_access_send_req however leaves a lot of the
standard vm_event fields to be filled by other functions.
Remove mem_access_send_req() completely, making use of monitor_traps() to put
requests into the monitor ring. This in turn causes some cleanup around the
old callsites of mem_access_send_req(). We also update monitor_traps to now
include setting the common vcpu_id field so that all other call-sites can ommit
this step.
Finally, this change identifies that errors from mem_access_send_req() were
never checked. As errors constitute a problem with the monitor ring,
crashing the domain is the most appropriate action to take.
Signed-off-by: Tamas K Lengyel <tamas.lengyel@zentific.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Lars Kurth