These functions don't belong in the common mem_access header as there is no #VE
equivalent on ARM.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
The library has been largely untouched for over a decade at this point, it is
undocumented and it's unclear what it was originally used for. Remove it from
tree, if anyone needs it in the future it can be carved out from git history.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Wei Liu <wl@xen.org>
Patch cf4b30dca0 "Add debug code to detect illegal page_lock and put_page_type
ordering" added extra sanity checking to page_lock/page_unlock for debug builds
with the assumption that no hypervisor path ever locks two pages at once.
This assumption doesn't hold during memory sharing so we copy a version of
page_lock/unlock to be used exclusively in the memory sharing subsystem
without the sanity checks.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Calling _put_page_type while also holding the page_lock for that page
can cause a deadlock. There may be code-paths still in place where this
is an issue, but for normal sharing purposes this has been tested and
works.
Removing grabbing the extra page reference at certain points is done
because it is no longer needed, a reference is held till necessary with
this reorder thus the extra reference is redundant.
The comment being dropped is incorrect since it's now out-of-date.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
The p2m_altp2m_lazy_copy is responsible for lazily populating an
altp2m view when the guest traps out due to no EPT entry being present
in the active view. Currently, in addition to taking a number of
unused argements, the whole calling convention has a number of
redundant p2m lookups: the function reads the hostp2m, even though the
caller has just read the same hostp2m entry; and then the caller
re-reads the altp2m entry that the function has just read (and possibly set).
Rework this function to make it a bit more rational. Specifically:
- Pass the current hostp2m entry values we have just read for it to
use to populate the altp2m entry if it finds the entry empty.
- If the altp2m entry is not empty, pass out the values we've read so
the caller doesn't need to re-walk the tables
- Either way, return with the gfn 'locked', to make clean-up handling
more consistent.
Rename the function to better reflect this functionality.
While we're here, change bool_t to bool, and return true/false rather
than 1/0.
It's a bit grating to do both the p2m_lock() and the get_gfn(),
knowing that they boil down to the same thing at the moment; but we
have to maintain the fiction until such time as we decide to get rid
of it entirely.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Tested-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Patch 0502e0adae "x86: correct instances of PGC_allocated clearing" introduced
grabbing extra references for pages that drop references tied to PGC_allocated.
However, these pages are actually owned by dom_cow, resulting both sharing and
unsharing breaking.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Receiving this register is useful for introspecting 32-bit Windows when the
event being trapped happened while in ring3.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Currently the gs_shadow value is only cached when the vCPU is being scheduled
out by Xen. Reporting this (usually) stale value through vm_event is incorrect,
since it doesn't represent the actual state of the vCPU at the time the event
was recorded. This prevents vm_event subscribers from correctly finding kernel
structures in the guest when it is trapped while in ring3.
Refresh shadow_gs value when the context being saved is for the current vCPU.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
When booting Xen via UEFI the Xen config file can contain multiple
sections each describing different boot options. It is currently only
possible to choose which section to boot with if the buffer contains a
string. UEFI provides a different standard to pass optional arguments
to an application, and in this patch we make Xen properly parse this
buffer, thus making it possible to have separate EFI boot options
present for the different config sections.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Clean up the handling of TRAP_int3 VMEXITs to conform to the handling
of TRAP_debug.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Since in-guest debug exceptions are now unconditionally trapped to Xen, adding
a hook for vm_event subscribers to tap into this new always-on guest event. We
rename along the way hvm_event_breakpoint_type to hvm_event_type to better
match the various events that can be passed with it. We also introduce the
necessary monitor_op domctl's to enable subscribing to the events.
This patch also provides monitor subscribers to int3 events proper access
to the instruction length necessary for accurate event-reinjection. Without
this subscribers manually have to evaluate if the int3 instruction has any
prefix attached which would change the instruction length.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The return value has not been clearly defined, with the function
never returning 0 which seemingly indicated a condition where the
guest should crash.
In this patch we define -rc as error condition where a subscriber is
present but an error prevented the notification from being sent;
0 where there is no subscriber or the notification was sent and the vCPU
is not paused (i.e. safe to continue execution as normal); and 1 where the
notification was sent with the vCPU paused and we are waiting for a
response.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
The monitor_get_capabilities check actually belongs to the monitor subsystem so
relocating and renaming it to sanitize the code's name and location. Mechanical
patch, no code changes introduced.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Without specifying the altp2m flag on the response the view never got switched.
Also, add extra information printouts that can be useful during debugging.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
Tamas K Lengyel