Currently we track in the TableDesc and CmdQDesc structs the state of
the GITS_BASER<n> and GITS_CBASER Valid bits. However we aren't very
consistent abut checking the valid field: we test it in update_cte()
and update_dte(), but not anywhere else we look things up in tables.
The GIC specification says that it is UNPREDICTABLE if a guest fails
to set any of these Valid bits before enabling the ITS via
GITS_CTLR.Enabled. So we can choose to handle Valid == 0 as
equivalent to a zero-length table. This is in fact how we're already
catching this case in most of the table-access paths: when Valid is 0
we leave the num_entries fields in TableDesc or CmdQDesc set to zero,
and then the out-of-bounds check "index >= num_entries" that we have
to do anyway before doing any of these table lookups will always be
true, catching the no-valid-table case without any extra code.
So we can remove the checks on the valid field from update_cte()
and update_dte(): since these happen after the bounds check there
was never any case when the test could fail. That means the valid
fields would be entirely unused, so just remove them.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220201193207.2771604-11-peter.maydell@linaro.org
Currently when we fill in a TableDesc based on the value the guest
has written to the GITS_BASER<n> register, we calculate both:
* num_entries : the number of entries in the table, constrained
by the amount of memory the guest has given it
* num_ids : the number of IDs we support for this table,
constrained by the implementation choices and the architecture
(eg DeviceIDs are 16 bits, so num_ids is 1 << 16)
When validating ITS commands, however, we check only num_ids,
thus allowing a broken guest to specify table entries that
index off the end of it. This will only corrupt guest memory,
but the ITS is supposed to reject such commands as invalid.
Instead of calculating both num_entries and num_ids, set
num_entries to the minimum of the two limits, and check that.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220122182444.724087-13-peter.maydell@linaro.org
The ITS code has to check whether various parameters passed in
commands are in-bounds, where the limit is defined in terms of the
number of bits that are available for the parameter. (For example,
the GITS_TYPER.Devbits ID register field specifies the number of
DeviceID bits minus 1, and device IDs passed in the MAPTI and MAPD
command packets must fit in that many bits.)
Currently we have off-by-one bugs in many of these bounds checks.
The typical problem is that we define a max_foo as 1 << n. In
the Devbits example, we set
s->dt.max_ids = 1UL << (GITS_TYPER.Devbits + 1).
However later when we do the bounds check we write
if (devid > s->dt.max_ids) { /* command error */ }
which incorrectly permits a devid of 1 << n.
These bugs will not cause QEMU crashes because the ID values being
checked are only used for accesses into tables held in guest memory
which we access with address_space_*() functions, but they are
incorrect behaviour of our emulation.
Fix them by standardizing on this pattern:
* bounds limits are named num_foos and are the 2^n value
(equal to the number of valid foo values)
* bounds checks are either
if (fooid < num_foos) { good }
or
if (fooid >= num_foos) { bad }
In this commit we fix the handling of the number of IDs
in the device table and the collection table, and the number
of commands that will fit in the command queue.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
The TableDesc struct defines properties of the in-guest-memory tables
which the guest tells us about by writing to the GITS_BASER<n>
registers. This struct currently has a union 'maxids', but all the
fields of the union have the same type (uint32_t) and do the same
thing (record one-greater-than the maximum ID value that can be used
as an index into the table).
We're about to add another table type (the GICv4 vPE table); rather
than adding another specifically-named union field for that table
type with the same type as the other union fields, remove the union
entirely and just have a 'uint32_t max_ids' struct field.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Defined descriptors for ITS device table,collection table and ITS
command queue entities.Implemented register read/write functions,
extract ITS table parameters and command queue parameters,extended
gicv3 common to capture qemu address space(which host the ITS table
platform memories required for subsequent ITS processing) and
initialize the same in ITS device.
Signed-off-by: Shashi Mallela <shashi.mallela@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Message-id: 20210910143951.92242-3-shashi.mallela@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Added register definitions relevant to ITS,implemented overall
ITS device framework with stubs for ITS control and translater
regions read/write,extended ITS common to handle mmio init between
existing kvm device and newer qemu device.
Signed-off-by: Shashi Mallela <shashi.mallela@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Message-id: 20210910143951.92242-2-shashi.mallela@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.
Patch generated using:
$ ./scripts/codeconverter/converter.py -i \
--pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')
which will split "typdef struct { ... } TypedefName"
declarations.
Followed by:
$ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
$(git grep -l '' -- '*.[ch]')
which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
We need to handle both registers and ITS tables. While
register handling is standard, ITS table handling is more
challenging since the kernel API is devised so that the
tables are flushed into guest RAM and not in vmstate buffers.
Flushing the ITS tables on device pre_save() is too late
since the guest RAM is already saved at this point.
Table flushing needs to happen when we are sure the vcpus
are stopped and before the last dirty page saving. The
right point is RUN_STATE_FINISH_MIGRATE but sometimes the
VM gets stopped before migration launch so let's simply
flush the tables each time the VM gets stopped.
For regular ITS registers we just can use vmstate pre_save()
and post_load() callbacks.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-id: 1497023553-18411-3-git-send-email-eric.auger@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is the basic skeleton for both KVM and software-emulated ITS.
Since we already prepare status structure, we also introduce complete
VMState description. But, because we currently have no migratable
implementations, we also set unmigratable flag.
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1474616617-366-3-git-send-email-eric.auger@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
