As compared to x86 the va of the hypervisor .text
is locked down - we cannot modify the running pagetables
to have the .ro flag unset. We borrow the same idea that
alternative patching has - which is to vmap the entire
.text region and use the alternative virtual address
for patching.
Since we are doing vmap we may fail, hence the
arch_livepatch_quiesce was changed (see "x86,arm:
Change arch_livepatch_quiesce() declaration") to return
an error value which will be bubbled in payload->rc and
provided to the user (along with messages in the ring buffer).
The livepatch virtual address space (where the new functions
are) needs to be close to the hypervisor virtual address
so that the trampoline can reach it. As such we re-use
the BOOT_RELOC_VIRT_START which is not used after bootup
(alternatively we can also use the space after the _end to
FIXMAP_ADDR(0), but that may be too small).
The ELF relocation engine at the start was coded from
the "ELF for the ARM 64-bit Architecture (AArch64)"
(http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf)
but after a while of trying to write the correct bit shifting
and masking from scratch I ended up borrowing from Linux, the
'reloc_insn_imm' (Linux v4.7 arch/arm64/kernel/module.c function.
See 257cb251925f854da435cbf79b140984413871ac "arm64: Loadable modules")
And while at it - we also utilize code from Linux to construct
the right branch instruction (see "arm64/insn: introduce
aarch64_insn_gen_{nop|branch_imm}() helper functions").
In the livepatch payload loading code we tweak the #ifdef to
only exclude ARM_32. The exceptions are not part of ARM 32/64 hence
they are still behind the #ifdef.
We also expand the MAINTAINERS file to include the arm64 and arm32
platform specific livepatch file.
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com> [non-arm parts]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
So they can be shared with ARM64 (but not yet, so they
are only built on x86).
No functional change.
We also need to tweak the MAINTAINERS and .gitignore file.
Also we need to update SUBDIRS to include the new 'test'
directory so 'cscope' can show the example livepatches.
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com> [arm change]
Acked-by: Jan Beulich <jbeulich@suse.com> [for directory]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The NOP functionality will NOP any of the code at
the 'old_addr' or at 'name' if the 'new_addr' is zero.
The purpose of this is to NOP out calls, such as:
e8 <4-bytes-offset>
(5 byte insn), or on ARM a 4 byte insn for branching.
We need the EIP of where we need to the NOP, and that can
be provided via the `old_addr` or `name`.
If the `old_addr` is provided we will NOP 'new_size'
amount of bytes at that location.
The amount is up to 31 instructions if desired (which is
the size of the opaque member). If there is a need to NOP
more then: a) more 'struct livepatch_func' structures need
to be present, b) we have to implement a variable size
buffer (in the future), or c) first byte an unconditional
branch skipping the to be disabled code (of course provided
there are no branch targets in the middle).
While at it, also unify the code on x86 patching so
it is a bit simpler (instead of two seperate writes
just make it one memcpy).
And introduce a general livepatch_insn_len inline function
that would depend on platform specific instruction size
(for a unconditional branch). As such we also rename the
PATCH_INSN_SIZE to ARCH_PATCH_INSN_SIZE.
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.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>
Specifically:
s/\.xsplice/\.livepatch/
s/XSPLICE/LIVEPATCH/
s/xsplice/livepatch/
s/livepatch_patch_func/livepatch_func/
s/xSplice/Xen Live Patch/
s/livepatching/livepatch/
s/arch_livepatch_enter/arch_livepatch_quiesce/
s/arch_livepatch_exit/arch_livepatch_revive/
And then modify some of the function arguments
to have two more characters.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
Clarify the meaning of nested maintainership.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
---
We had a discussion about the meaning of nested maintainership at the
recent Xen Hackathon. The notes of that meeting can be found on this
list [1]. No decision is official until discussed on this list, so
consider this patch the official proposal for this change, and object
or ask for clarification accordingly.
Compared to v1, there is one change that is worth pointing out: The
claim that THE REST consists of all committers. This is the case at
the moment, but this change would codify that this is an invariant we
intend to keep going forward.
The advantage of this is that the dispute resolution mentioned in this
patch for maintainers who can't agree lines up directly with the
fall-back for broader community issues upon which we can't reach
consensus.
[1] marc.info/?i=<EDB48431-C3EF-4461-B2D2-3AB95EA6C392@gmail.com>
Changes in v2:
- fixed spelling of "maintainer"
- fixed path of multi.c
- clarified that the resolution by REST would be by *majority* vote
- Asserted that The REST consists of all committers
CC: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Jan Beulich <jbeulich@suse.com>
CC: Keir Fraser <keir@xen.org>
CC: Tim Deegan <tim@xen.org>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Konrad Wilk <konrad.wilk@oracle.com>
CC: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Lars Kurth <lars.kurth@citrix.com>
I've been getting increasingly annoyed by people not applying common
sense to these docs updates.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Julien Grall <julien.grall@arm.com>
Commit 108788e8 "x86/hvm: separate ioreq server code from generic hvm
code" split the code supporting ioreq servers from the rest of the HVM
code. Now that this is separate, the new files can be added to the x86
I/O emulation file list in MAINTAINERS.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
I have made many modifications to this code over the past few years
so I'm probably the one most familiar with it.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Update my email address.
Remove myself from STUB DOMAINS, MINI-OS and TOOLSTACK, where I haven't
been active recently.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
I nominate Anthony Perard as qemu-xen co-maintainer. He has been doing a
lot of QEMU work over the years and in fact he is the original author of
the Xen enablement code in upstream QEMU.
As qemu-xen co-maintainer, he could help me manage the qemu-xen trees
and promptly backport all the relevant commits from upstream QEMU.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Meng Xu is one of the maintainers of the RT-Xen project,
which is from where the RTDS scheduler comes. He also
is the main author of the version of RTDS that we currently
have here upstream.
Since the upstreaming effort, he's continued looking after
the code, engaging with the community, coming and presenting
at XenSummits and, last but not least, doing development
himself as well as directing the work of others, with the
aim of improving the scheduler.
In summary, he has reached the point, both from thechnical
and community engagement point of views, where he can
effectively serve as a maintainer of RTDS code.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Meng Xu <mengxu@cis.upenn.edu>
Acked-by: George Dunlap <george.dunlap@citrix.com>
I would like to propose Julien Grall (julien.grall@arm.com) as
co-maintainer for Xen on ARM. His track record of contributions to the
project is outstanding and I think speaks for itself.
Julien made multiple public presentations about Xen on ARM at Xen
Developer Summit and Linaro Connect conferences. He led the development
of several key features, such as SMMU support and non-PCI passthrough
and participated in the design and the review of large code
contributions from others.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
This patch moves monitor_domctl to common-side.
Purpose: move what's common to common, prepare for implementation
of such vm-events on ARM.
* move get_capabilities to arch-side => arch_monitor_get_capabilities.
* add arch-side monitor op handling function => arch_monitor_domctl_op.
e.g. X86-side handles XEN_DOMCTL_MONITOR_OP_EMULATE_EACH_REP op
* add arch-side monitor event handling function => arch_monitor_domctl_event.
e.g. X86-side handles XEN_DOMCTL_MONITOR_EVENT_MOV_TO_MSR event enable/disable
* remove status_check
Signed-off-by: Corneliu ZUZU <czuzu@bitdefender.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Since we will add ACPI initialization for UART in this file later,
rename it with a generic name.
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
This platform is no longer actively used, but it makes GICv2 development
harder.
Signed-off-by: Zoltan Kiss <zoltan.kiss@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Move a few misplaced entries into their intended (alphabetical) slots.
Update qemu and mini-os tree info.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
It was lost when vpmu* files were moved from xen/arch/x86/hvm/{vmx|svm}/ to
xen/arch/x86/cpu/
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
The component being unmaintained right now and him being the apparently
only user at present, this certainly is an improvement over the current
situation.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tamas K Lengyel <tamas@tklengyel.com>
As well as CC-ing the correct people. I just saw such a request on
xen-users and thought this was worth clarifying here too.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
It is no longer used.
One complication is that xc_map_m2p() has users in xc_offline_page.c,
xen-mfndump and xen-mceinj. Move its implementation into
xc_offline_page (for want of a better location) beside it's current
user.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- drop mentions of removed files from MAINTAINERS ]
Add tools/tests/xen-acess to the supported list under VM EVENT/MEM ACCESS.
Also, changing my e-mail to the preferred one, as it is in many of the headers
already.
Signed-off-by: Tamas K Lengyel <tlengyel@novetta.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Add an option to the vm_event response to toggle singlestepping on the vCPU.
This is only supported on Intel CPUs which have Monitor Trap Flag capability.
Signed-off-by: Tamas K Lengyel <tlengyel@novetta.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: Ian Campbell <Ian.campbell@citrix.com>
Boris Ostrovsky