All of this is as recommended by the Intel whitepaper:
https://software.intel.com/sites/default/files/managed/1d/46/Retpoline-A-Branch-Target-Injection-Mitigation.pdf
The 'RSB Alternative' bit in MSR_ARCH_CAPABILITIES may be set by a hypervisor
to indicate that the virtual machine may migrate to a processor which isn't
retpoline-safe. Introduce a shortened name (to reduce code volume), treat it
as authorative in retpoline_safe(), and print its value along with the other
ARCH_CAPS bits.
The exact processor models which do have RSB semantics which fall back to BTB
predictions are enumerated, and include Kabylake and Coffeelake. Leave a
printk() in the default case to help identify cases which aren't covered.
The exact microcode versions from Broadwell RSB-safety are taken from the
referenced microcode update file (adjusting for the known-bad microcode
versions). Despite the exact wording of the text, it is only Broadwell
processors which need a microcode check.
In practice, this means that all Broadwell hardware with up-to-date microcode
will use retpoline in preference to IBRS, which will be a performance
improvement for desktop and server systems which would previously always opt
for IBRS over retpoline.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Current interface to the gntdev in FreeBSD is wrong, and mostly worked
out of luck before the PTI FreeBSD fixes, when kernel and user-space
where sharing the same page tables.
On FreeBSD ioctls have the size of the passed struct encoded in the ioctl
number, because the generic ioctl handler in the OS takes care of
copying the data from user-space to kernel space, and then calls the
device specific ioctl handler. Thus using ioctl structs with variable
sizes is not possible.
The fix is to turn the array of structs at the end of
ioctl_gntdev_alloc_gref and ioctl_gntdev_map_grant_ref into pointers,
that can be properly accessed from the kernel gntdev driver using the
copyin/copyout functions. Note that this is exactly how it's done for
the privcmd driver.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The main purpose of this patch is to avoid opencoding the recovery logic at
the end, but also has the positive side effect of relaxing the SPEC_CTRL
mitigations when working to shut the final CPU down.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Following commit a6aa678fa3 ("x86/msr: Correct the emulation behaviour
of MSR_PRED_CMD") we may end up writing the low bit with the wrong
value. While it's unlikely for a guest to want to write zero there, we
should still permit (this without incurring the overhead of an actual
barrier). Correcting this right away will also help whenever further
bits in the MSR might become defined.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
The minios tag `xen-4.11.0-rc1' was mistakenly made on the wrong
revision. So we have burned that tag and use xen-4.11.0-rc1.1
instead.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
qemu upstream uses git submodules. git archive does not work with git
submodules (and could not work properly with them, because this is one
of the many things it is inherently impossible to do correctly with
git submodules).
qemu upstream have worked around this by providing a rather scary
shell script which attempts to do roughly the right thing. It's close
enough that we can use it with only minor precautions.
Unfortunately this does mean that `mktarball' now executes the qemu
source code it was using, rather than merely shuffling it about, as it
did previously. I think this is a less bad ill than copying (and,
effectively, forking) the scary script.
CC: Wei Liu <wei.liu2@citrix.com>
CC: George Dunlap <george.dunlap@eu.citrix.com>
CC: Juergen Gross <jgross@suse.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
* Change 'int i' to being unsigned, and move it into its most narrow scope.
* Fold the access_ok() checks for %dr{0..3}. This halves the compiled size
of the function.
* Additional newlines in appropriate places.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
set_debugreg() has several bugs:
* %dr4/5 should function correctly as aliases of %dr6/7 when CR4.DE is clear.
* Attempting to set the upper 32 bits of %dr6/7 should fail with #GP[0]
rather than be silently corrected and complete.
* For emulation, the #UD and #GP[0] cases need properly distinguishing. Use
-ENODEV for #UD cases, leaving -EINVAL (bad bits) and -EPERM (not allowed to
use that valid bit) as before for hypercall callers.
* A write which clears %dr7.L/G leaves the IO shadow intact, meaning that
subsequent reads of %dr7 will see stale IO watchpoint configuration.
Implement x86emul_write_dr() as a thin wrapper around set_debugreg().
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
do_get_debugreg() has several bugs:
* The %cr4.de condition is inverted. %dr4/5 should be accessible only when
%cr4.de is disabled.
* When %cr4.de is disabled, emulation should yield #UD rather than complete
with zero.
* Using -EINVAL for errors is a broken ABI, as it overlaps with valid values
near the top of the address space.
Introduce a common x86emul_read_dr() handler (as we will eventually want to
add HVM support) which separates its success/failure indication from the data
value, and have do_get_debugreg() call into the handler.
The ABI of do_get_debugreg() remains broken, but switches from -EINVAL to
-ENODEV for compatibility with the changes in the following patch.
Take the opportunity to add a missing local variable block to x86_emulate.c
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Experimentally, the behaviour of reserved bits in MSR_PRED_CMD changed between
beta and production microcode, and now raises a #GP fault for set reserved
bits. The AMD spec for future hardware also specifies this behaviour, and it
is the more sensible behaviour to implement.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
The "end" address must be rounded down before shifting,
otherwise we will insert wrong page range to a heap if address isn't
page aligned.
It seems that a copy-paste mistake took place in the following commit:
0c12972e34
xen/mm: Switch some of page_alloc.c to typesafe MFN
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Make sure no previously present features are missing after resume (and
the re-loading of microcode), to avoid later crashes or (likely silent)
hangs / live locks. This doesn't go beyond checking x86_capability[],
but this should be good enough for the immediate need of making sure
that the BIT mitigation MSRs are still available.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
NMI and #MC can occur at any time after S3 resume, yet the MSR_SPEC_CTRL
may become available only once we're reloaded microcode. Make
SPEC_CTRL_ENTRY_FROM_INTR_IST and DO_SPEC_CTRL_EXIT_TO_XEN no-ops for
the critical period of time.
Also set the MSR back to its intended value.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Microcode loading needs to happen before re-enabling interrupts, in case
only updated microcode allows the use of e.g. the SPEC_{CTRL,CMD} MSRs.
Otoh it doesn't need to happen at all when we didn't suspend in the
first place. It needs to happen before spin_debug_enable() though, as it
acquires a lock and hence would otherwise make
common/spinlock.c:check_lock() unhappy. As micrcode loading can be
pretty verbose, also make sure it only runs after console_end_sync().
cpufreq_add_cpu() doesn't need calling on the only "goto enable_cpu"
path, which sits ahead of cpufreq_del_cpu().
Reported-by: Simon Gaiser <simon@invisiblethingslab.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
7782db9260 "docs/gen-html-index: Extract titles from HTML documents"
requires HTML::TreeBuilder::XPath.
This is sadly not as widely available as I had hoped. Work around
this problem by making the use of this module optional: instead of
`use'ing at the toplevel, we `require' it in the eval. If it's not
present, then the title is simply not extracted and the filename is
used as before, which is tolerable.
Also add some debugging.
Reported-by: Doug Goldstein <cardoe@cardoe.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
Tested-by: Doug Goldstein <cardoe@cardoe.com>
In order to provide explicit stream parameter negotiation between
backend and frontend the following changes are introduced in the protocol:
add XENSND_OP_HW_PARAM_QUERY request to read/update
configuration space for the parameter given: request passes
desired parameter interval (mask) and the response to this request
returns min/max interval (mask) for the parameter to be used.
Parameters supported by this request/response:
- format mask
- sample rate interval
- number of channels interval
- buffer size, interval, frames
- period size, interval, frames
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
In order to provide explicit synchronization between backend and
frontend the following changes are introduced in the protocol:
- add new ring buffer for sending asynchronous events from
backend to frontend to report number of bytes played by the
frontend (XENSND_EVT_CUR_POS)
- introduce trigger events for playback control: start/stop/pause/resume
- add "req-" prefix to event-channel and ring-ref to unify naming
of the Xen event channels for requests and events
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Oleksandr Grytsov <oleksandr_grytsov@epam.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Protocol version was referenced in the protocol description,
but missed its definition. Fix this by adding a constant
for current protocol version.
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
A section in the SUPPORT.md may mention multiple
Status, something: Supported
and then have some text. The text is linked to from [*] footnotes
in the table. But, this means that each bit of text needs to
apply to multiple rows.
Before this commit this was a separate [*] after each applicable item.
But multiple apparently-different links to the same thing are annoying
for the reader.
So, in this commit we combine them. Formatting the result is not
entirely trivial.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
---
v3: New patch
v3.1: Drop `}' in multi-row [*] notes. I put this in to help work
around firefox bugs eg
https://bugzilla.mozilla.org/show_bug.cgi?id=244135
but I have been convinced it is not generally wanted.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
This archaeology script:
- figures out what the current and previous Xen versions were
- looks for appropriate git branches for them
- finds SUPPORT.md for each one
- feeds its findings to parse-support-md
We do not intend to integrate this into docs/Makefile, because it
relies on the git history. Instead, we will take the rune provided in
the head comment and paste a variant of it into an appropriate cronjob
on xenbits.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Acked-by: Lars Kurth <lars.kurth@citrix.com>
---
v3: Provide -D option.
This utility reads json format pandoc output, from parsing one or more
SUPPORT.md files, and generates an HTML table element containing the
principal version and feature information.
This is rather hairier than I anticipated when I started out; hence
the 400-odd-line Perl script.
Machinery to assemble the appropriate inputs for parse-support-md
will be in the next commit.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Acked-by: Lars Kurth <lars.kurth@citrix.com>
---
v2: New in this version of the series.
v3: Refactor to introduce RealSect
v3: Add [*] footnote to all applicable entries, not just the last
We are going to want to format SUPPORT.md which does not match the
filename patterns in docs/. So provide a way to make an ad-hoc rule
using pandoc with the standard options.
No functional change in this patch.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Acked-by: Lars Kurth <lars.kurth@citrix.com>
This commits (more or less) this file to be processed with pandoc,
rather than other markdown processors. There is, unfortunately, no
widely-accepted way to declare a title for the document.
I tested feeding the document to markdown(1) on Debian jessie and it
reproduced the % line as if it were simple text. I guess many other
markdown processors will do something similarly tolerable. My
internet searches did not discover a markdown processor that used
lines starting with % for something else.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Lars Kurth <lars.kurth@citrix.com>
Continuations of bullet list items must be indented by exactly 4
spaces (according to pandoc_markdown(5) on Debian jessie).
This is most easily achieved by making the bullet list items have two
spaces before the `*'.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Lars Kurth <lars.kurth@citrix.com>
We don't break up port requests in case they cross emulation entity
boundaries, and a write to an I/O port is necessarily the last
operation of an instruction instance, so there's no need to re-invoke
the full emulation path upon receiving the result from an external
emulator.
In case we want to properly split port accesses in the future, this
change will need to be reverted, as it would prevent things working
correctly when e.g. the first part needs to go to an external emulator,
while the second part is to be handled internally.
While this addresses the reported problem of Windows paging out the
buffer underneath an in-process REP OUTS, it does not address the wider
problem of the re-issued insn (to the insn emulator) being prone to
raise an exception (#PF) during a replayed, previously successful memory
access (we only record prior MMIO accesses).
Leaving aside the problem tried to be worked around here, I think the
performance aspect alone is a good reason to change the behavior.
Also take the opportunity and change bool_t -> bool as
hvm_vcpu_io_need_completion()'s return type.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
c/s 74fd984ae "tools/libxl: Drop xc_domain_configuration_t from
libxl__domain_build_state" removed state->config completely but missed
some conversion libxl_arm.c.
Furthermore, not all the fields of xc_domain_configuration_t have a
corresponding field in libxl_domain_build_info. This is the case of
clock_frequency. As the field should not be exposed to the user, add a
corresponding field in libxl__domain_build_state. This require some
modification in the prototype of libxl__domain_make in order to have the
state.
For all the other fields, use the up-to-date version in
libxl_domain_build_info.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Commit f20a6e309 removed a parameter from smp_prepare_cpus but only
the x86 parts were submitted and committed.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Commit 4a5733771e ("libxl: put RSDP for PVH guest near 4GB") breaks
pre-4.17 Linux guests since they do not use start_info's rsdp_paddr
pointer and instread scan BIOS memory for RSDP signature.
Introduce XENFEAT_linux_rsdp_unrestricted feature flag that indicates
whether the guest can handle RSDP at locations pointed to by
rsdp_paddr.
Since only Linux PVH guests suffer from this problem (BSD has always
relied on rsdp_paddr) we check this flag just for those guests. If the
flag is not set we place RSDP in BIOS, as before.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
The existing FLAT_KERNEL_SS expands to the correct value, 0xe02b, but is the
wrong constant to use. Switch to FLAT_USER_SS32.
For compat domains however, the reported values are entirely bogus.
FLAT_USER_SS32 (value 0xe02b) is FLAT_RING3_CS in the 32bit ABI, while
FLAT_USER_CS32 (value 0xe023) is FLAT_RING1_DS with an RPL of 3.
The guests SYSCALL callback is invoked with a broken iret frame, and if left
unmodified by the guest, will fail on the way back out when Xen's iret tries
to load a code segment into %ss.
In practice, this is only a problem for 32bit PV guests on AMD hardware, as
Intel hardware doesn't permit the SYSCALL instruction outside of 64bit mode.
This appears to have been broken ever since 64bit support was added to Xen,
and has gone unnoticed because Linux doesn't use SYSCALL in 32bit builds.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
Most of the users of page_to_mfn and mfn_to_page are either overriding
the macros to make them work with mfn_t or use mfn_x/_mfn because the
rest of the function use mfn_t.
So make page_to_mfn and mfn_to_page return mfn_t by default. The __*
version are now dropped as this patch will convert all the remaining
non-typesafe callers.
Only reasonable clean-ups are done in this patch. The rest will use
_mfn/mfn_x for the time being.
Lastly, domain_page_to_mfn is also converted to use mfn_t given that
most of the callers are now switched to _mfn(domain_page_to_mfn(...)).
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Other than MFN 0 -> INVALID_MFN, no functional change intended.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
At the same time replace MFN 0 by INVALID_MFN or drop the initializer
when it is not necessary. This will make clearer that the MFN
initialized is not valid.
Other than MFN 0 -> INVALID_MFN, no functional change intended.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
The current prototype is slightly confusing because it takes a guest
physical address and a machine physical frame (not address!). Switching to
MFN will improve safety and reduce the chance to mistakenly invert the
2 parameters.
Signed-off-by: Julien grall <julien.grall@arm.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
A new helper __copy_mfn_to_guest is introduced to easily to copy a MFN to
the guest memory.
Not functional change intended
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The current prototype is slightly confusing because it takes a virtual
address and a physical frame (not address!). Switching to MFN will improve
safety and reduce the chance to mistakenly invert the 2 parameters.
Also, take the opportunity to switch (a - b) >> PAGE_SHIFT to
PFN_DOWN(a - b) in the code modified.
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Andrew Cooper
Roger Pau Monne
Jan Beulich
Ian Jackson
Oleksandr Tyshchenko
Oleksandr Andrushchenko
Julien Grall
Wei Liu
Boris Ostrovsky
Amit Singh Tomar