Early versions of the VT-d spec mentioned 6-level paging support as a
possible value for the SAGAW capability, but later versions removed it
and SAGAW=0x10 is currently listed as a reserved value.
The 6-level (agaw=64) entry in sagaw_bits is furthermore problematic
with clang15 because the attempted comparison against 1ULL << 64 in
dmar_maxaddr2mgaw() causes the compiler to elide the last iteration
of the initial loop, which bypasses the subsequent logic to find the
greatest HW-supported address width. This results in 5-level paging
always being selected regardless of whether the hardware supports it,
which can result address translation failure due to invalid context-
entry programming.
Reviewed by: kib
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D39896
Otherwise POSTREAD syncs may re-invalidate the shadow of the data buffer
when copying from bounce pages, resulting in false-positive KMSAN
reports.
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
A signed one-bit wide bit-field can take only the values 0 and -1. Clang
16 introduced a warning that "implicit truncation from 'int' to a
one-bit wide bit-field changes value from 1 to -1". Fix the warnings by
using C99 bool.
Reported by: Clang 16
Reviewed by: emaste, jhb
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D39705
The xen_domain_type and HYPERVISOR_shared_info variables are shared by
all Xen architectures, so they should be in common rather than
reimplemented by each architecture.
hvm_start_flags is used by xen_initial_domain() and so needs to be in
common.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D28982
The event channel source code or equivalent is needed on all
architectures. Since much of this is viable to share, get this moved out
of x86-land. Each interrupt interface then needs a distinct back-end
implementation.
Reviewed by: royger
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Original implementation: Julien Grall <julien@xen.org>, 2014-01-13 17:41:04
Differential Revision: https://reviews.freebsd.org/D30236
Simply moving the interrupt allocation and release functions into files
which belong to the architecture. Since x86 interrupt handling is quite
distinct from other architectures, this is a crucial necessary step.
Identifying the border between x86 and architecture-independent is
actually quite tricky. Similarly, getting the prototypes for the
border right is also quite tricky.
Inspired by the work of Julien Grall <julien@xen.org>,
2015-10-20 09:14:56, but heavily adjusted.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30936
The x86 PIC interface is very much x86-specific and not used by other
architectures. Since most of xen_intr.c can be shared with other
architectures, the PIC interface needs to be broken off.
Introduce wrappers for calls into the architecture-dependent interrupt
layer. All architectures need roughly the same functionality, but the
interface is slightly different between architectures. Due to the
wrappers being so thin, all of them are implemented as inline in
arch-intr.h.
The original implementation was done by Julien Grall in 2015, but this
has required major updating.
Removal of PVHv1 meant substantial portions disappeared. The original
implementation took care of moving interrupt allocation to
xen_arch_intr.c, but this has required massive rework and was broken
off.
In the original implementation the wrappers were normal functions. Some
had empty stubs in xen_intr.c and were removed.
Reviewed by: royger
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Original implementation: Julien Grall <julien@xen.org>, 2015-10-20 09:14:56
Differential Revision: https://reviews.freebsd.org/D30909
This value doesn't need to be set in xen_intr_alloc_isrc(). What is
needed is simply to ensure the allocated xenisrc won't appear as free,
even if xi_type is written non-atomically. Since the type is no longer
used to indicate free or not, the calling function should take care of
all non-architecture initialization.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D31188
Scanning the list of interrupts to find an unused entry is rather
inefficient. Instead overlay a free list structure and use a list
instead.
This also has the useful effect of removing the last use of evtchn_type
values outside of xen_intr.c.
Reviewed by: royger
[royger]
- Make avail_list static.
Move the xenisrc structure which needs to be shared between the core Xen
interrupt code and architecture-dependent code into a separate header. A
similar situation exists for the NR_EVENT_CHANNELS constant.
Turn xi_intsrc into a type definition named xi_arch to reflect the new
purpose of being an architectural variable for the interrupt source.
This was originally implemented by Julien Grall, but has been heavily
modified. The core side was renamed "intr-internal.h" and is #include'd
by "arch-intr.h" instead of the other way around. This allows the
architecture to add function definitions which use struct xenisrc.
The original version only moved xi_intsrc into xen_arch_isrc_t. Moving
xi_vector was done by the submitter.
The submitter had also moved xi_activehi and xi_edgetrigger into
xen_arch_isrc_t. Those disappeared with the removal of PVHv1 support.
Copyright note. The current xenisrc structure was introduced at
76acc41fb7 by Justin T. Gibbs. Traces remain, but the strength of
Copyright claims from before 2013 seem pretty weak.
Reviewed by: royger
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>, 2021-03-17 19:09:01
Original implementation: Julien Grall <julien@xen.org>, 2015-10-20 09:14:56
Differential Revision: https://reviews.freebsd.org/D30648
[royger]
- Adjust some line lengths
- Fix comment about NR_EVENT_CHANNELS after movement.
- Use #include instead of symlinks.
xen_intr_handle_upcall() has two interfaces. It needs to be called by
the x86 assembly code invoked by the APIC. Second, it needs to be called
as a driver_filter_t for the XenPCI code and for architectures besides
x86.
Unfortunately the driver_filter_t interface was implemented as a wrapper
around the x86-APIC interface. Now create a simple wrapper for the
x86-APIC code, which calls an architecture-independent
xen_intr_handle_upcall().
When called via intr_event_handle(), driver_filter_t functions expect
preemption to be disabled. This removes the need for
critical_enter()/critical_exit() when called this way.
The lapic_eoi() call is only needed on x86 in some cases when invoked
directly as an APIC vector handler.
Additionally driver_filter_t functions have no need to handle interrupt
counters. The intrcnt_add() calling function was reworked to match the
current situation. intrcnt_add() is now only called via one path.
The increment/decrement of curthread->td_intr_nesting_level had
previously been left out. Appears this was mostly harmless, but this
was noticed during implementation and has been added.
CONFIG_X86 is a leftover from use with Linux. While the barrier isn't
needed for FreeBSD on x86, it will be needed for FreeBSD on other
architectures.
Copyright note. xen_intr_intrcnt_add() was introduced at 76acc41fb7
by Justin T. Gibbs. xen_intrcnt_init() was introduced at fd036deac1
by John Baldwin.
sys/x86/xen/xen_arch_intr.c was originally created by Julien Grall in
2015 for the purpose of holding the x86 interrupt interface. Later it
was found xen_intr_handle_upcall() was better earlier, and the x86
interrupt interface better later. As such the filename and header list
belong to Julien Grall, but what those were created for is later.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30006
Keeping released xenisrcs in a known state simplifies allocation, but
forces the allocation function to maintain that state. This turns into
a problem when trying to allow for interchangeable allocation functions.
Fix this issue by ensuring xenisrcs are always *fully* initialized
during binding.
Reviewed by: royger
There are actually several distinct locking domains in xen_intr.c, but
all were sharing the same lock. Both xen_intr_port_to_isrc[] and the
x86 interrupt structures needed protection. Split these two apart as a
precursor to splitting the architecture portions off the file.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30726
Locking for allocation was being done in xen_intr_bind_isrc(), but the
unlock was inside xen_intr_alloc_isrc(). While the lock acquisition at
the end of xen_intr_alloc_isrc() was to modify xen_intr_port_to_isrc[],
NOT allocation. Fix this garbled (though working) locking scheme.
Now locking for allocation is strictly in xen_intr_alloc_isrc(), while
locking to modify xen_intr_port_to_isrc[] is in xen_intr_bind_isrc().
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30726
The call structure around xen_intr_alloc_isrc() was rather awful.
Notably finding a structure for reuse is part of allocation, but this
was done outside xen_intr_alloc_isrc(). Move this into
xen_intr_alloc_isrc() so the function handles all allocation steps.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30726
As "CPUs", IRQs (vector) and virtual IRQs are always positive integers,
adjust the Xen code to use unsigned integers. Several format strings
need adjustment to match. Additionally single-bit bitfields are
boolean.
No functional change expected.
Reviewed by: royger
Part of the series for allowing FreeBSD/ARM to run on Xen. On ARM the
function is a trivial pass-through, other architectures need distinct
implementations.
While implementing XEN_VCPUID() as a call to XEN_CPUID_TO_VCPUID()
works, that involves multiple accesses to the PCPU region. As such make
this a distinct macro. Only callers in machine independent code have
been switched.
Add a wrapper for the x86 PIC interface to use matching the old
prototype.
Partially inspired by the work of Julien Grall <julien@xen.org>,
2015-08-01 09:45:06, but XEN_VCPUID() was redone by Elliott Mitchell on
2022-06-13 12:51:57.
Reviewed by: royger
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Original implementation: Julien Grall <julien@xen.org>, 2014-04-19 08:57:40
Original implementation: Julien Grall <julien@xen.org>, 2014-04-19 14:32:01
Differential Revision: https://reviews.freebsd.org/D29404
Previously the upper layer handle was being set before the last
potential error condition. The reasoning appears to have been it was
assumed invalid in case of an error being returned. Now ensure it is
invalid until just before a successful return.
Fixes: 76acc41fb7 ("Implement vector callback for PVHVM and unify event channel implementations")
Fixes: 6d54cab1fe ("xen: allow to register event channels without handlers")
Reviewed by: royger
The prior implementation of xen_intr_resume() was wiping
xen_intr_port_to_isrc[] and then rebuilding from the x86 interrupt
table. Rework to instead wipe the channel numbers (->xi_port) and then
scan the table for sources with invalid channels.
This will be slower due to scanning the whole table, but this removes
the dependency on the x86 interrupt code.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30599
[royger]
Split line over 80 characters.
The portions of xen_rebind_ipi() and xen_rebind_virq() were already
near-identical. While xen_rebind_ipi() should panic() on
single-processor, still having the functionality to invoke seems
harmless.
Meanwhile much of the loop from xen_intr_resume() seemed to want to be
closer to this same code. This pushes related bits closer together.
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30598
Remove these no longer needed headers. Key for making xen_intr.c
machine-independent as they don't exist on other architectures.
Originally this was part of a much larger commit, but was broken off
for submission to the FreeBSD project.
Reviewed by: royger
Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Original implementation: Julien Grall <julien@xen.org>, 2015-10-20 09:14:56
MFC after: 1 week
Now that the atomic macros are always genuinely atomic on x86, they can
be used for synchronization with Xen. A single core VM isn't too
unusual, but actual single core hardware is uncommon.
Replace an open-coding of evtchn_clear_port() with the inline.
Substantially inspired by work done by Julien Grall <julien@xen.org>,
2014-01-13 17:40:58.
Reviewed by: royger
MFC after: 1 week
While unusual, intr_register_source() can return failure. A likely
cause might be another device grabbing from Xen's interrupt range.
This should NOT happen, but could happen due to a bug. As such check
for this and fail if it occurs.
This theoretical situation also effects xen_intr_find_unused_isrc().
There, .is_pic must be tested to ensure such an intrusion doesn't cause
misbehavior.
Reviewed by: royger
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D31995
Consistently use ~0 instead of 0 when clearing xenisrc structures.
0 is a valid event channel number, even though it is reserved by Xen.
Whereas ~0 is guaranteed invalid.
Reviewed by: royger
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30743
In xen_intr_release_isrc(), the isrc should only be removed if it is
assigned to a valid port. This had been mitigated by using 0 for not
having a port, but this is actually corrupting the table. Fix this bug
as modifying the code would cause this bug to manifest as kernel memory
corruption. Similar issue for the vCPU bitmap masks.
The KASSERT() doesn't need lock protection.
Reviewed by: royger
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30743
The comparison was wrong. Hopefully this never occurred in the wild,
but now ensure the error message will occur before damage is caused.
This appears non-exploitable as exploitation would require a guest to
force Domain 0 to allocate all event channels, which a guest shouldn't
be able to do.
Adjust the error message to better describe what has occurred.
Reviewed by: royger
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30743
Appears errors are uncommon since calling xen_intr_release_isrc() on a
xenisrc with xi_close in an undefined state could be bad. Fix this
problematic lurking nasty.
Reviewed by: royger
MFC after: 1 week
The Intel graphics stolen memory is used by the Intel GOP driver on
boot. When using bhyve with GPU passthrough, it's also used by the guest
GOP driver at guest boot. For that reason, bhyve needs to know the
address and size of this region to inform the guest about this region.
Exposing the variables as sysctl allows bhyve to easily read them.
In 38d1ac34ff SIGATOMIC_{MIN,MAX} were
defined in terms of LONG_{MIN,MAX}. Later, they were switched to
__LONG_{MIN,MAX} in 78fe75bc28 where an
include of machine/_limits.h was added. Switch to using fixed width
INT64_{MIN,MAX} and remove the header pollution.
No functional change.
Reviewed by: theraven, emaste
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D39196
Newer Intel CPUs/iGPUs use a new method to determine the base address of
the stolen memory. This code was ported from Linux.
Reviewed by: manu
Approved by: manu
Differential Revision: https://reviews.freebsd.org/D39057
Make a pass at the various nexus implementations, fixing some very minor
style issues, obsolete comments, etc.
The method declaration section has become unwieldy in many respects.
Attempt to tame it by:
- Using generated method typedefs
- Grouping methods roughly by category, and then alphabetically.
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D38495
The xenpf_dom0_console_t structure can grow as more data is added, and
hence we need to check that the fields we accesses have been filled by
Xen. The only extra field FreeBSD currently uses is the top 32 bits
for the frame buffer physical address.
Note that this field is present in all the versions that make the
information available from the platform hypercall interface, so the
check here is mostly cosmetic, and to remember us that newly added
fields require checking the size of the returned data.
Fixes: 6f80738b22 ('xen: fetch dom0 video console information from Xen')
Sponsored by: Citrix Systems R&D
It's possible for Xen to switch the video mode set by the boot loader,
so that the information passed in the kernel metadata is no longer
valid. Fetch the video mode used by Xen using an hypercall and update
the medatada for the kernel to use the correct video mode.
Sponsored by: Citrix Systems R&D
This is required for a further change that will make use of a field
that was added in version 0x00040d00.
No functional change expected.
Sponsored by: Citrix Systems R&D
This makes the detection of VMs common between platforms that
have SMBios.
Reviewed by: imp, kib
Differential Revision: https://reviews.freebsd.org/D38800
If a CPU for some reason returns 0 as CPU frequency, we currently panic
on the resulting divide by zero when trying to initialize the CPU(s) via
APIC. When this happens, we'll fallback to measuring the frequency
instead.
PR: 269767
Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/664
When the cycle counter is "stable", i.e., synchronized across vCPUs by
the hypervisor, userspace can use a serialized rdtsc instead of relying
on rdtscp, just like the kernel timecounter does. This can be useful
for performance in guests where the hypervisor hides rdtscp for some
reason.
To avoid breaking compatibility with older userspace which expects
rdtscp to be usable when pvclock exports timekeeping info, hide this
feature behind a sysctl.
Reviewed by: kib
Tested by: Shrikanth R Kamath <kshrikanth@juniper.net>
MFC after: 2 weeks
Sponsored by: Klara, Inc.
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D38342
Exposing the a power loss of the rtc as an sysctl makes it easier to
detect an empty cmos battery.
Reviewed by: manu
MFC after: 1 week
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D38325
