Commit Graph
39887 Commits
Author SHA1 Message Date
Julien Grall 62529f16c8 xen/arm32: head: Use a page mapping for the 1:1 mapping in create_page_tables()
At the moment the function create_page_tables() will use 1GB/2MB
mapping for the identity mapping. As we don't know what is present
before and after Xen in memory, we may end up to map
device/reserved-memory with cacheable memory. This may result to
mismatched attributes as other users may access the same region
differently.

To prevent any issues, we should only map the strict minimum in the
1:1 mapping. A check in xen.lds.S already guarantees anything
necessary for turning on the MMU fits in a page (at the moment 4K).

As only one page will be mapped for the 1:1 mapping, it is necessary
to pre-allocate a page for the 3rd level table.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall 23dfe48d10 xen/arm32: head: Introduce macros to create table and mapping entry
At the moment, any update to the boot-pages are open-coded. This is
making more difficult to understand the logic of a function as each
update roughly requires 6 instructions.

To ease the readability, two new macros are introduced:
    - create_table_entry: Create a page-table entry in a given table.
    This can work at any level.
    - create_mapping_entry: Create a mapping entry in a given table.
    None of the users will require to map at any other level than 3rd
    (i.e page granularity). So the macro is only supporting 3rd level
    mapping.

Unlike arm64, there are no easy way to have a PC relative address within
the range -/+4GB. In order to have the possibility to use the macro in
context with MMU on/off, the user needs to tell the state of the MMU.

Lastly, take the opportunity to replace open-coded version in
setup_fixmap() by the two new macros. The ones in create_page_tables()
will be replaced in a follow-up patch.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall e14d26424b xen/arm64: head: Use a page mapping for the 1:1 mapping in create_page_tables()
At the moment the function create_page_tables() will use 1GB/2MB
mapping for the identity mapping. As we don't know what is present
before and after Xen in memory, we may end up to map
device/reserved-memory with cacheable memory. This may result to
mismatched attributes as other users may access the same region
differently.

To prevent any issues, we should only map the strict minimum in the
1:1 mapping. A check in xen.lds.S already guarantees anything
necessary for turning on the MMU fits in a page (at the moment 4K).

As only one page will be mapped for the 1:1 mapping, it is necessary
to pre-allocate a page for the 3rd level table.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall 93dc90db04 xen/arm64: head: Introduce macros to create table and mapping entry
At the moment, any update to the boot-pages are open-coded. This is
making more difficult to understand the logic of a function as each
update roughly requires 6 instructions.

To ease the readability, two new macros are introduced:
    - create_table_entry: Create a page-table entry in a given table.
    This can work at any level.
    - create_mapping_entry: Create a mapping entry in a given table.
    None of the users will require to map at any other level than 3rd
    (i.e page granularity). So the macro is only supporting 3rd level
    mapping.

Furthermore, the two macros are capable to work independently of the
state of the MMU.

Lastly, take the opportunity to replace open-coded version in
setup_fixmap() by the two new macros. The ones in create_page_tables()
will be replaced in a follow-up patch.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall b03f75e22a xen/arm32: head: Rework and document setup_fixmap()
At the moment, the fixmap table is only hooked when earlyprintk is used.
This is fine today because in C land, the fixmap is not used by anyone
until the the boot CPU is switching to the runtime page-tables.

In the future, the boot CPU will not switch between page-tables to
avoid TLB incoherency. Thus, the fixmap table will need to be always
hooked beofre any use. Let's start doing it now in setup_fixmap().

Lastly, document the behavior and the main registers usage within the
function.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall e79999e587 xen/arm32: head: Remove 1:1 mapping as soon as it is not used
The 1:1 mapping may clash with other parts of the Xen virtual memory
layout. At the moment, Xen is handling the clash by only creating a
mapping to the runtime virtual address before enabling the MMU.

The rest of the mappings (such as the fixmap) will be mapped after the
MMU is enabled. However, the code doing the mapping is not safe as it
replace mapping without using the Break-Before-Make sequence.

As the 1:1 mapping can be anywhere in the memory, it is easier to remove
all the entries added as soon as the 1:1 mapping is not used rather than
adding the Break-Before-Make sequence everywhere.

It is difficult to track where exactly the 1:1 mapping was created
without a full rework of create_page_tables(). Instead, introduce a new
function remove_identity_mapping() will look where is the top-level entry
for the 1:1 mapping and remove it.

The new function is only called for the boot CPU. Secondary CPUs will
switch directly to the runtime page-tables so there are no need to
remove the 1:1 mapping. Note that this still doesn't make the Secondary
CPUs path safe but it is not making it worst.

Note that the TLB flush sequence is same sequence as described in
asm-arm/arm32/flushtlb.h with a twist. Per G5-5532 ARM DDI 0487D.a,
a dsb nsh is sufficient for local flushed. Note the section is from the
AArch32 Armv8 spec, I wasn't able to find the same exact section in the
Armv7 spec but this is dotted as local operations only applies to
non-shareable domain. This was missed while reworking the header and
therefore a more conservative way was adopted.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall e8e6bca4d8 xen/arm64: head: Rework and document setup_fixmap()
At the moment, the fixmap table is only hooked when earlyprintk is used.
This is fine today because in C land, the fixmap is not used by anyone
until the the boot CPU is switching to the runtime page-tables.

In the future, the boot CPU will not switch between page-tables to
avoid TLB incoherency. Thus, the fixmap table will need to be always
hooked before any use. Let's start doing it now in setup_fixmap().

Lastly, document the behavior and the main registers usage within the
function.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Julien Grall 2b11c36461 xen/arm64: head: Remove 1:1 mapping as soon as it is not used
The 1:1 mapping may clash with other parts of the Xen virtual memory
layout. At the moment, Xen is handling the clash by only creating a
mapping to the runtime virtual address before enabling the MMU.

The rest of the mappings (such as the fixmap) will be mapped after the
MMU is enabled. However, the code doing the mapping is not safe as it
replace mapping without using the Break-Before-Make sequence.

As the 1:1 mapping can be anywhere in the memory, it is easier to remove
all the entries added as soon as the 1:1 mapping is not used rather than
adding the Break-Before-Make sequence everywhere.

It is difficult to track where exactly the 1:1 mapping was created
without a full rework of create_page_tables(). Instead, introduce a new
function remove_identity_mapping() will look where is the top-level entry
for the 1:1 mapping and remove it.

The new function is only called for the boot CPU. Secondary CPUs will
switch directly to the runtime page-tables so there are no need to
remove the 1:1 mapping. Note that this still doesn't make the Secondary
CPUs path safe but it is not making it worst.

Note that the TLB flush sequence is same sequence as described in
asm-arm/arm32/flushtlb.h with a twist. Per D5-2530 ARM DDI 0487D.a,
a dsb nsh is sufficient for local flush. This part of the Arm Arm
was missed while reworking the header and therefore a more conservative
way was adopted.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2019-09-26 16:03:39 +01:00
Oleksandr Tyshchenko 32350c5bbd iommu/arm: Add Renesas IPMMU-VMSA support
The IPMMU-VMSA is VMSA-compatible I/O Memory Management Unit (IOMMU)
which provides address translation and access protection functionalities
to processing units and interconnect networks.

Please note, current driver is supposed to work only with newest
R-Car Gen3 SoCs revisions which IPMMU hardware supports stage 2 translation
table format and is able to use CPU's P2M table as is if one is
3-level page table (up to 40 bit IPA).

The major differences compare to the Linux driver are:

1. Stage 1/Stage 2 translation. Linux driver supports Stage 1
translation only (with Stage 1 translation table format). It manages
page table by itself. But Xen driver supports Stage 2 translation
(with Stage 2 translation table format) to be able to share the P2M
with the CPU. Stage 1 translation is always bypassed in Xen driver.

So, Xen driver is supposed to be used with newest R-Car Gen3 SoC revisions
only (H3 ES3.0, M3-W+, etc.) which IPMMU H/W supports stage 2 translation
table format.

2. AArch64 support. Linux driver uses VMSAv8-32 mode, while Xen driver
enables Armv8 VMSAv8-64 mode to cover up to 40 bit input address.

3. Context bank (sets of page table) usage. In Xen, each context bank is
mapped to one Xen domain. So, all devices being pass throughed to the
same Xen domain share the same context bank.

4. IPMMU device tracking. In Xen, all IOMMU devices are managed
by single driver instance. So, driver uses global list to keep track
of registered IPMMU devices.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
[for the IPMMU H/W bits]
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
[julien: Remove unneeded "default n"]
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-26 15:52:01 +01:00
Oleksandr Tyshchenko 3e27f7d4cf iommu/arm: Introduce iommu_add_dt_device API
The main puprose of this patch is to add a way to register DT device
(which is behind the IOMMU) using the generic IOMMU DT bindings [1]
before assigning that device to a domain.

So, this patch adds new "iommu_add_dt_device" API for adding DT device
to the IOMMU using generic IOMMU DT bindings and previously added
"iommu_fwspec" support. As devices can be assigned to the hardware domain
and other domains this function is called from two places: handle_device()
and iommu_do_dt_domctl().

Besides that, this patch adds new "dt_xlate" callback (borrowed from
Linux "of_xlate") for providing the driver with DT IOMMU specifier
which describes the IOMMU master interfaces of that device (device IDs, etc).
According to the generic IOMMU DT bindings the context of required
properties for IOMMU device/master node (#iommu-cells, iommus) depends
on many factors and is really driver depended thing.

Please note, all IOMMU drivers which support generic IOMMU DT bindings
should use "dt_xlate" and "add_device" callbacks.

[1] https://www.kernel.org/doc/Documentation/devicetree/bindings/iommu/iommu.txt

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2019-09-26 15:51:52 +01:00
Oleksandr Tyshchenko e386739529 iommu: Order the headers alphabetically in device_tree.c
Clean up the code a bit by putting the headers in alphabetical order.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-26 14:35:32 +01:00
Oleksandr Tyshchenko 292189a56c iommu/arm: Add lightweight iommu_fwspec support
We need to have some abstract way to add new device to the IOMMU
based on the generic IOMMU DT bindings [1] which can be used for
both DT (right now) and ACPI (in future).

For that reason we can borrow the idea used in Linux these days
called "iommu_fwspec". Having this in, it will be possible
to configure IOMMU master interfaces of the device (device IDs)
from a single common place and avoid keeping almost identical look-up
implementations in each IOMMU driver.

There is no need to port the whole implementation of "iommu_fwspec"
to Xen, we could, probably, end up with a much simpler solution,
some "stripped down" version which fits our requirements.

So, this patch adds the following:
1. A common structure "iommu_fwspec" to hold the the per-device
   firmware data
2. New member "iommu_fwspec" of struct device
3. Functions/helpers to deal with "dev->iommu_fwspec"

It should be noted that in comparison of the original "iommu_fwspec"
Xen's variant doesn't contain some fields, which are not really
needed at the moment (ops, flag) and "iommu_fwnode" field was replaced
by "iommu_dev" to avoid porting a lot of code (to support "fwnode_handle")
with little benefit.

The "iommu_fwspec" support is based on the Linux's commit:
f74c2bb98776e2de508f4d607cd519873065118e "Linux 5.3-rc8"

Subsequent patches will use of that support.

[1] https://www.kernel.org/doc/Documentation/devicetree/bindings/iommu/iommu.txt

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-26 14:35:32 +01:00
Oleksandr Tyshchenko efc882ffb7 xen/common: Introduce xrealloc_flex_struct() helper macros
This patch introduces type-safe helper macros to re-allocate space
for a structure with a flexible array of typed objects.

For example, if we need to re-size the "data" array:

   struct arrlen
   {
      size_t len;
      int data[];
   };

We can use the proposed macros in the following way:

   new_ptr = realloc_flex_struct(old_ptr, data, nr_elem);

where nr_elem is the desired number of elements.

Subsequent patch will use this macros.

Also, while here, introduce xmalloc(xzalloc)_flex_struct() to
allocate space for a structure with a flexible array of typed objects.

Suggested-by: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
CC: Andrew Cooper <andrew.cooper3@citrix.com>
CC: George Dunlap <George.Dunlap@eu.citrix.com>
CC: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Julien Grall <julien.grall@arm.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Stefano Stabellini <sstabellini@kernel.org>
CC: Tim Deegan <tim@xen.org>
CC: Wei Liu <wl@xen.org>
2019-09-26 14:35:32 +01:00
Oleksandr Tyshchenko 50879e805e xen/common: Introduce _xrealloc function
This patch introduces type-unsafe function which besides
re-allocation handles the following corner cases:
1. if requested size is zero, it will behave like xfree
2. if incoming pointer is not valid (NULL or ZERO_BLOCK_PTR),
   it will behave like xmalloc

If both pointer and size are valid the function will re-allocate and
copy only if requested size and alignment don't fit in already
allocated space.

Subsequent patch will add type-safe helper macros.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
[julien: comestic changes]
Acked-by: Julien Grall <julien.grall@arm.com>
CC: Andrew Cooper <andrew.cooper3@citrix.com>
CC: George Dunlap <George.Dunlap@eu.citrix.com>
CC: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Stefano Stabellini <sstabellini@kernel.org>
CC: Tim Deegan <tim@xen.org>
CC: Wei Liu <wl@xen.org>
CC: Paul Durrant <paul.durrant@citrix.com>
2019-09-26 14:34:36 +01:00
Oleksandr Tyshchenko 805b77579a iommu/arm: Add ability to handle deferred probing request
This patch adds minimal required support to General IOMMU framework
to be able to handle a case when IOMMU driver requesting deferred
probing for a device.

In order not to pull Linux's error code (-EPROBE_DEFER) to Xen
we have chosen -EAGAIN to be used for indicating that device
probing is deferred.

This is needed for the upcoming IPMMU driver which may request
deferred probing depending on what device will be probed the first
(there is some dependency between these devices, Root device must be
registered before Cache devices. If not the case, driver will deny
further Cache device probes until Root device is registered).
As we can't guarantee a fixed pre-defined order for the device nodes
in DT, we need to be ready for the situation where devices being
probed in "any" order.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
2019-09-26 14:31:04 +01:00
Oleksandr Tyshchenko 9001ad4d7c iommu/arm: Add iommu_helpers.c file to keep common for IOMMUs stuff
Introduce a separate file to keep various helpers which could be used
by more than one IOMMU driver in order not to duplicate code.

The first candidates to be moved to the new file are SMMU driver's
"map_page/unmap_page" callbacks. These callbacks neither contain any
SMMU specific info nor perform any SMMU specific actions and are going
to be the same across all IOMMU drivers which H/W IP shares P2M
with the CPU like SMMU does.

So, move callbacks to iommu_helpers.c for the upcoming IPMMU driver
to be able to re-use them.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-26 14:31:04 +01:00
Paul Durrant 52633db2c5 iommu: avoid triggering ASSERT_UNREACHABLE() on ARM...
...when the IOMMU is not enabled.

80ff3d338d "iommu: tidy up iommu_use_hap_pt() and need_iommu_pt_sync()
macros" introduced CONFIG_IOMMU_FORCE_PT_SHARE, which causes the global
'iommu_hap_pt_share' option to be replaced with a #define-d value of true.
In this configuration, calling clear_iommu_hap_pt_share() will result
trigger the aforementioned ASSERT.

CONFIG_IOMMU_FORCE_PT_SHARE is always selected for ARM builds and,
because clear_iommu_hap_pt_share() is called by the common iommu_setup()
function if the IOMMU is not enabled, it is no longer safe to disable the
IOMMU on ARM systems.

However, running with the IOMMU disabled is a valid configuration for ARM
systems, so this patch rectifies the problem by removing the call to
clear_iommu_hap_pt_share() from common code. As a side effect of this,
however, it becomes possible on x86 systems for iommu_enabled to be false
but iommu_hap_pt_share to be true. Thus the code in sysctl.c
needs to be changed to make sure that XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share
is not erroneously advertised when the IOMMU has been disabled.

Reported-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2019-09-26 14:30:32 +01:00
Andrew Cooper 8f78242899 x86/cpuid: Enable CPUID Faulting for PV control domains by default
The domain builder no longer uses local CPUID instructions for policy
decisions.  This resolves a key issue for PVH dom0's.  However, as PV dom0's
have never had faulting enforced, leave a command line option to restore the
old behaviour.

Advertise virtualised faulting support to control domains unless the opt-out
has been used.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper 6df43b32ab x86/domctl: Drop XEN_DOMCTL_set_cpuid
With the final users moved over to using XEN_DOMCTL_set_cpumsr_policy, drop
this domctl and associated infrastructure.

Rename the preexisting set_cpuid XSM vector to set_cpu_policy, now that it is
back to having a single user.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper 685e922d6f tools/libxc: Rework xc_cpuid_apply_policy() to use {get,set}_cpu_policy()
The purpose of this change is to stop using xc_cpuid_do_domctl(), and to stop
basing decisions on a local CPUID instruction.  This is not a correct or
appropriate way to construct policy information for other domains.

The overwhelming majority of this logic is redundant with the policy logic in
Xen, but has a habit of becoming stale (e.g. c/s 97e4ebdcd7 resulting in the
CPUID.7[1].eax not being offered to guests even when Xen is happy with the
content).

There are a few subtle side effects which need to remain in place.  A
successful call to xc_cpuid_apply_policy() must result in a call to
xc_set_domain_cpu_policy() because that is currently the only way the
ITSC/VMX/SVM bits become reflected in the guests CPUID view.  Future cleanup
will remove this side effect.

The topology tweaks are local to libxc.  Extend struct cpuid_policy with
enough named fields to express the logic, but keep it identical to before.
Fixing topology representation is another future area of work.

No (expected) change in behaviour.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper e5b02b085e tools/libxc: Rework xc_cpuid_set() to use {get,set}_cpu_policy()
The purpose of this change is to stop using xc_cpuid_do_domctl(), and to stop
basing decisions on a local CPUID instruction.  This is not an appropriate way
to construct policy information for other domains.

Obtain the host and domain-max policies from Xen, and mix the results as
before.  Provide rather more error logging than before.

No semantics changes to xc_cpuid_set().  There are conceptual problems with
how the function works, which will be addressed in future toolstack work.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper 53b4a87a4c tools/libxc: Pre-cleanup for xc_cpuid_{set,apply_policy}()
This patch is broken out just to simplify the following two.

For xc_cpuid_set(), document how the 's' and 'k' options works because it is
quite subtle.  Replace a memset() with a for loop of 4 explicit NULL
assigments.  This mirrors the free()'s in the fail path.

For xc_cpuid_apply_policy(), const-ify the featureset pointer.  It isn't
written to, and was never intended to be mutable.

Drop three pieces of trailing whitespace.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper 14ba07e6f8 x86/domctl: Implement XEN_DOMCTL_set_cpumsr_policy
This hypercall allows the toolstack to present one combined CPUID and MSR
policy for a domain, which can be audited in one go by Xen, which is necessary
for correctness of the auditing.

Reuse the existing set_cpuid XSM access vector, as this is logically the same
operation.

As x86_cpu_policies_are_compatible() is still only a stub, retain the call to
recalculate_cpuid_policy() to discard unsafe toolstack settings.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Sergey Dyasli <sergey.dyasli@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper 205f3b6380 x86/cpuid: Split update_domain_cpuid_info() in half
update_domain_cpuid_info() currently serves two purposes.  First to merge new
CPUID data from the toolstack, and second, to perform any necessary updating
of derived domain/vcpu settings.

The first part of this is going to be superseded by a new and substantially
more efficient hypercall.

Carve the second part out into a new domain_cpu_policy_changed() helper, and
call this from the remains of update_domain_cpuid_info().

This does drop the call_policy_changed, but with the new hypercall in place,
the common case will be a single call per domain.  Dropping the optimisation
here allows for a cleaner set of following changes.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper 588a966a57 libx86: Introduce x86_cpu_policies_are_compatible()
This helper will eventually be the core "can a guest configured like this run
on the CPU?" logic.  For now, it is just enough of a stub to allow us to
replace the hypercall interface while retaining the previous behaviour.

It will be expanded as various other bits of CPUID handling get cleaned up.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper f001579288 libx86: Proactively initialise error pointers
This results in better behaviour for the caller.

Suggested-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Andrew Cooper ff78e50084 x86/msr: Offer CPUID Faulting to PVH control domains
The control domain exclusion for CPUID Faulting predates dom0 PVH, but the
reason for the exclusion (to allow the domain builder to see host CPUID
values) isn't applicable.

The domain builder *is* broken in PVH control domains, and restricting the use
of CPUID Faulting doesn't make it any less broken.  Tweak the logic to only
exclude PV control domains.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-26 13:40:18 +01:00
Volodymyr Babchuk 433387661e xen/arm: optee: update description in Kconfig
OP-TEE mediator now is "Tech Preview" state, and we want to update
it's description in Kconfig accordingly.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-25 16:01:32 +01:00
Volodymyr Babchuk e9ad55d9ad SUPPORT.md: Describe OP-TEE mediator
With the latest patches to the mediator, it can be considered
as Technological Preview feature.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-25 16:01:29 +01:00
Volodymyr Babchuk c2c141f0f4 xen/arm: optee: handle shared buffer translation error
There is a case possible, when OP-TEE asks guest to allocate shared
buffer, but Xen for some reason can't translate buffer's addresses. In
this situation we should do two things:

1. Tell guest to free allocated buffer, so there will be no memory
leak for guest.

2. Tell OP-TEE that buffer allocation failed.

To ask guest to free allocated buffer we should perform the same
thing, as OP-TEE does - issue RPC request. This is done by filling
request buffer (luckily we can reuse the same buffer, that OP-TEE used
to issue original request) and then return to guest with special
return code.

Then we need to handle next call from guest in a special way: as RPC
was issued by Xen, not by OP-TEE, it should be handled by Xen.
Basically, this is the mechanism to preempt OP-TEE mediator.

The same mechanism can be used in the future to preempt mediator
during translation large (>512 pages) shared buffers.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-25 16:01:16 +01:00
Paul Durrant babde47a3f introduce a 'passthrough' configuration option to xl.cfg...
...and hence the ability to disable IOMMU mappings, and control EPT
sharing.

This patch introduces a new 'libxl_passthrough' enumeration into
libxl_domain_create_info. The value will be set by xl either when it parses
a new 'passthrough' option in xl.cfg, or implicitly if there is passthrough
hardware specified for the domain.

If the value of the passthrough configuration option is 'disabled' then
the XEN_DOMCTL_CDF_iommu flag will be clear in the xen_domctl_createdomain
flags, thus allowing the toolstack to control whether the domain gets
IOMMU mappings or not (where previously they were globally set).

If the value of the passthrough configuration option is 'sync_pt' then
a new 'iommu_opts' field in xen_domctl_createdomain will be set with the
value XEN_DOMCTL_IOMMU_no_sharept. This will override the global default
set in iommu_hap_pt_share, thus allowing the toolstack to control whether
EPT sharing is used for the domain.

If the value of passthrough is 'enabled' then xl will choose an appropriate
default according to the type of domain and hardware support.

NOTE: The 'iommu_memkb' overhead in libxl_domain_build_info will now only
      be set if passthrough is 'sync_pt' (or xl has chosen this mode as
      a default).

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
2019-09-25 16:14:55 +02:00
Ian Jackson 8d8db5a4ad tools/ocaml: abi check: Cope with consecutive relevant enums
If the end of one enum is the `type' line for the next enum, we would
not notice it.

Fix this by reordering the code, and getting rid of the else: now if
the "we are within an enum" branch decides that it's the end of the
enum, it unsets $ei and we then immediately process the line as a "not
within an enum" line - ie as the start of the next one.

Reported-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2019-09-25 16:14:21 +02:00
Paul Durrant 80ff3d338d iommu: tidy up iommu_use_hap_pt() and need_iommu_pt_sync() macros
Thes macros really ought to live in the common xen/iommu.h header rather
then being distributed amongst architecture specific iommu headers and
xen/sched.h. This patch moves them there.

NOTE: Disabling 'sharept' in the command line iommu options should really
      be hard error on ARM (as opposed to just being ignored), so define
      'iommu_hap_pt_share' to be true for ARM (via ARM-selected
      CONFIG_IOMMU_FORCE_PT_SHARE).

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>
2019-09-25 16:12:49 +02:00
Paul Durrant f89f555827 remove late (on-demand) construction of IOMMU page tables
Now that there is a per-domain IOMMU-enable flag, which should be set if
any device is going to be passed through, stop deferring page table
construction until the assignment is done. Also don't tear down the tables
again when the last device is de-assigned; defer that task until domain
destruction.

This allows the has_iommu_pt() helper and iommu_status enumeration to be
removed. Calls to has_iommu_pt() are simply replaced by calls to
is_iommu_enabled(). Remaining open-coded tests of iommu_hap_pt_share can
also be replaced by calls to iommu_use_hap_pt().
The arch_iommu_populate_page_table() and iommu_construct() functions become
redundant, as does the 'strict mode' dom0 page_list mapping code in
iommu_hwdom_init(), and iommu_teardown() can be made static is its only
remaining caller, iommu_domain_destroy(), is within the same source
module.

All in all, about 220 lines of code are removed from the hypervisor (at
the expense of some additions in the toolstack).

NOTE: This patch will cause a small amount of extra resource to be used
      to accommodate IOMMU page tables that may never be used, since the
      per-domain IOMMU-enable flag is currently set to the value of the
      global iommu_enable flag. A subsequent patch will add an option to
      the toolstack to allow it to be turned off if there is no intention
      to assign passthrough hardware to the domain.
      To account for the extra resource, 'iommu_memkb' has been added to
      domain_build_info. This patch sets it to a value calculated based
      on the domain's maximum memory when the P2M sharing is either not
      supported or globally disabled, or zero otherwise. However, when
      the toolstack option mentioned above is added, it will also be zero
      if the per-domain IOMMU-enable flag is turned off.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Alexandru Isaila <aisaila@bitdefender.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Wei Liu <wl@xen.org>
2019-09-25 16:12:02 +02:00
Jan Beulich 322609f9c9 AMD/IOMMU: tidy struct ivrs_mappings
Move the device flags field up into an unused hole, thus shrinking
overall structure size by 8 bytes. Use bool and uint<N>_t as
appropriate. Drop pointless (redundant) initializations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:03:48 +02:00
Jan Beulich 34a9ef62d3 AMD/IOMMU: restrict interrupt remapping table sizes
There's no point setting up tables with more space than a PCI device can
use. For both MSI and MSI-X we can determine how many interrupts could
be set up at most. Tables allocated during ACPI table parsing, however,
will (for now at least) continue to be set up to have maximum size.

Note that until we would want to use sub-page allocations here there's
no point checking whether both MSI and MSI-X are supported by a device -
an order-0 allocation will fit the dual case in any event, no matter
that the MSI-X vector count may be smaller than the MSI one.

On my Rome system this reduces space needed from just over 1k pages to
about 125.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:02:59 +02:00
Jan Beulich bb038f3116 AMD/IOMMU: replace INTREMAP_ENTRIES
Prepare for the number of entries to not be the maximum possible, by
separating checks against maximum size from ones against actual size.
For caller side simplicity have alloc_intremap_entry() return the
maximum possible value upon allocation failure, rather than the first
just out-of-bounds one.

Have the involved functions already take all the subsequently needed
arguments here already, to reduce code churn in the patch actually
making the allocation size dynamic.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
2019-09-25 16:02:21 +02:00
Jan Beulich 93a7810126 x86/PCI: read maximum MSI vector count early
Rather than doing this every time we set up interrupts for a device
anew (and then in several places) fill this invariant field right after
allocating struct pci_dev.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:01:31 +02:00
Jan Beulich 4e5e40fbd5 AMD/IOMMU: make phantom functions share interrupt remapping tables
Rather than duplicating entries in amd_iommu_msi_msg_update_ire(), share
the tables. This mainly requires some care while freeing them, to avoid
freeing memory blocks twice.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
2019-09-25 16:00:46 +02:00
Jan Beulich d7cfeb7c13 AMD/IOMMU: don't blindly allocate interrupt remapping tables
ACPI tables are free to list far more device coordinates than there are
actual devices. By delaying the table allocations for most cases, and
doing them only when an actual device is known to be present at a given
position, overall memory used for the tables goes down from over 500k
pages to just over 1k (on my system having such ACPI table contents).

Tables continue to get allocated right away for special entries
(IO-APIC, HPET) as well as for alias IDs. While in the former case
that's simply because there may not be any device at a given position,
in the latter case this is to avoid having to introduce ref-counting of
table usage.

The change involves invoking
iterate_ivrs_mappings(amd_iommu_setup_device_table) a second time,
because the function now wants to be able to find PCI devices, which
isn't possible yet when IOMMU setup happens very early during x2APIC
mode setup. In this context amd_iommu_init_interrupt() gets renamed as
well.

The logic adjusting a DTE's interrupt remapping attributes also gets
changed, such that the lack of an IRT would result in target aborted
rather than non-remapped interrupts (should any occur).

Note that for now phantom functions get separate IRTs allocated, as was
the case before.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 16:00:05 +02:00
Jan Beulich ff22a91b4c ACPI/cpuidle: bump maximum number of power states we support
Commit 4c6cd64519 ("mwait_idle: Skylake Client Support") added a table
with 8 entries, which - together with C0 - rendered the current limit
too low. It should have been accompanied by an increase of the constant;
do this now. Don't bump by too much though, as there are a number of on-
stack arrays which are dimensioned by this constant.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-25 15:53:35 +02:00
Juergen Gross b6656e6aa4 sched: fix freeing per-vcpu data in sched_move_domain()
In case of an allocation error of per-vcpu data in sched_move_domain()
the already allocated data is freed just using xfree(). This is wrong
as some schedulers need to do additional operations (e.g. the arinc653
scheduler needs to remove the vcpu-data from a list).

So instead xfree() make use of the sched_free_vdata() hook.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Dario Faggioli <dfaggioli@suse.com>
2019-09-25 15:52:53 +02:00
Jan Beulich 4f54473d00 SVM: correct CPUID event processing
hvm_monitor_cpuid() expects the input registers, not two of the outputs
(it was this way right from its introduction by commit d05f1eb374
["hvm/svm: implement CPUID events"]).

However, once having made the necessary adjustment, the SVM and VMX
functions are so similar that they should be folded (thus avoiding
further similar asymmetries to get introduced). Use the best of both
worlds by e.g. using "curr" consistently. This then being the only
caller of hvm_check_cpuid_faulting(), fold in that function as well.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Alexandru Isaila <aisaila@bitdefender.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2019-09-25 15:51:52 +02:00
Jan Beulich c9c7ac508b libxc/x86: correct overflow avoidance check in AMD CPUID handling
Commit df29d03f1d ("libxc/x86: avoid certain overflows in CPUID APIC ID
adjustments" introduced a one bit too narrow mask when checking whether
multiplying by 1 (in particular in leaf 1) would result in overflow.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-25 15:50:58 +02:00
Julien Grall f93abf0315 xen: sched: Fix Arm build after commit f855dd9625
Commit f855dd9625 "sched: add minimalistic idle scheduler for free cpus"
introduce the use of ZERO_BLOCK_PTR in the scheduler code. However, the
define does not exist outside of xmalloc_tsf.c for non-x86 architecture.

This will result to a compilation error on Arm:

schedule.c: In function ‘sched_idle_alloc_vdata’:
schedule.c:100:12: error: ‘ZERO_BLOCK_PTR’ undeclared (first use in this function)
     return ZERO_BLOCK_PTR;
                 ^~~~~~~~~~~~~~
schedule.c:100:12: note: each undeclared identifier is reported only once for each function it appears in
schedule.c:101:1: error: control reaches end of non-void function [-Werror=return-type]
 }
 ^
cc1: all warnings being treated as errors

To avoid the compilation error, the default definition for
ZERO_BLOCK_PTR is now moved in xen/config.h allowing all the code to use
the define.

Fixes: f855dd9625 ('sched: add minimalistic idle scheduler for free cpus')
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-24 18:58:55 +01:00
Juergen Gross d07bdb43f2 sched: switch to debugtrace in cpupool handling
Instead of having a cpupool_dprintk() define just use debugtrace.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Dario Faggioli <dfaggioli@suse.com>
2019-09-24 17:11:38 +02:00
Juergen Gross f855dd9625 sched: add minimalistic idle scheduler for free cpus
Instead of having a full blown scheduler running for the free cpus
add a very minimalistic scheduler for that purpose only ever scheduling
the related idle vcpu. This has the big advantage of not needing any
per-cpu, per-domain or per-scheduling unit data for free cpus and in
turn simplifying moving cpus to and from cpupools a lot.

Right now, CPUs that are not in any pool, still belong to Pool-0's
scheduler. This forces us to make, within the scheduler, extra effort
to avoid actually running vCPUs on those.

In the case of Credit1, this also cause issue to weights
(re)distribution, as the number of CPUs available to the scheduler is
wrong.

This is described in the changelog of commit e719192026 ("xen:
credit2: never consider CPUs outside of our cpupool").

This new scheduler will just use a common lock for all free cpus.

As this new scheduler is not user selectable don't register it as an
official scheduler, but just include it in schedule.c.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Dario Faggioli <dfaggioli@suse.com>
2019-09-24 17:11:02 +02:00
Juergen Gross 73d1d61fa9 sched: remove cpu from pool0 before removing it
Today a cpu which is removed from the system is taken directly from
Pool0 to the offline state. This will conflict with the new idle
scheduler, so remove it from Pool0 first. Additionally accept removing
a free cpu instead of requiring it to be in Pool0.

For the resume failed case we need to call the scheduler code for that
situation after the cpupool handling, so move the scheduler code into
a function and call it from cpupool_cpu_remove_forced() and remove the
CPU_RESUME_FAILED case from cpu_schedule_callback().

Note that we are calling now schedule_cpu_switch() in stop_machine
context so we need to switch from spinlock_irq to spinlock_irqsave.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Dario Faggioli <dfaggioli@suse.com>
Tested-by: Dario Faggioli <dfaggioli@suse.com>
2019-09-24 17:10:06 +02:00
Jan Beulich df29d03f1d libxc/x86: avoid certain overflows in CPUID APIC ID adjustments
Recent AMD processors may report up to 128 logical processors in CPUID
leaf 1. Doubling this value produces 0 (which OSes sincerely dislike),
as the respective field is only 8 bits wide. Suppress doubling the value
(and its leaf 0x80000008 counterpart) in such a case.

Note that while there's a similar overflow in intel_xc_cpuid_policy(),
that one is being left alone for now.

Note further that while it was considered to suppress the multiplication
by 2 altogether if the host topology already provides at least one bit
of thread ID within APIC IDs, it was decided to avoid more change here
than really needed at this point.

Also zap leaf 4 (and at the same time leaf 2) EDX output for AMD, as it
should have been from the beginning.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2019-09-24 10:50:33 +02:00
Alexandru Isaila b8443cb39b x86/emulate: send vm_event from emulate
A/D bit writes (on page walks) can be considered benign by an introspection
agent, so receiving vm_events for them is a pessimization. We try here to
optimize by filtering these events out.
Currently, we are fully emulating the instruction at RIP when the hardware sees
an EPT fault with npfec.kind != npfec_kind_with_gla. This is, however,
incorrect, because the instruction at RIP might legitimately cause an
EPT fault of its own while accessing a _different_ page from the original one,
where A/D were set.
The solution is to perform the whole emulation, while ignoring EPT restrictions
for the walk part, and taking them into account for the "actual" emulating of
the instruction at RIP. When we send out a vm_event, we don't want the emulation
to complete, since in that case we won't be able to veto whatever it is doing.
That would mean that we can't actually prevent any malicious activity, instead
we'd only be able to report on it.
When we see a "send-vm_event" case while emulating, we need to first send the
event out and then suspend the emulation (return X86EMUL_RETRY).
After the emulation stops we'll call hvm_vm_event_do_resume() again after the
introspection agent treats the event and resumes the guest. There, the
instruction at RIP will be fully emulated (with the EPT ignored) if the
introspection application allows it, and the guest will continue to run past
the instruction.

A common example is if the hardware exits because of an EPT fault caused by a
page walk, p2m_mem_access_check() decides if it is going to send a vm_event.
If the vm_event was sent and it would be treated so it runs the instruction
at RIP, that instruction might also hit a protected page and provoke a vm_event.

Now if npfec.kind == npfec_kind_in_gpt and d->arch.monitor.inguest_pagefault_disabled
is true then we are in the page walk case and we can do this emulation optimization
and emulate the page walk while ignoring the EPT, but don't ignore the EPT for the
emulation of the actual instruction.

In the first case we would have 2 EPT events, in the second case we would have
1 EPT event if the instruction at the RIP triggers an EPT event.

We use hvmemul_map_linear_addr() to intercept write access and
__hvm_copy() to intercept exec, read and write access.

A new return type was added, HVMTRANS_need_retry, in order to have all
the places that consume HVMTRANS* return X86EMUL_RETRY.

hvm_emulate_send_vm_event() can return false if there was no violation,
if there was an error from monitor_traps() or p2m_get_mem_access().
-ESRCH from p2m_get_mem_access() is treated as restricted access.

NOTE: hvm_emulate_send_vm_event() assumes the caller will enable/disable
arch.vm_event->send_event

Signed-off-by: Alexandru Isaila <aisaila@bitdefender.com>
Acked-by: Paul Durrant <paul@xen.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Razvan Cojocaru <rcojocaru@bitdefender.com>
Reviewed-by: Petre Pircalabu <ppircalabu@bitdefender.com>
2019-09-24 10:49:36 +02:00