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3105 commits

Author SHA1 Message Date
Edgar E. Iglesias a30a478538
tcg: Add tcg_set_insn_param
Add tcg_set_insn_param as a mechanism to modify an insn
parameter after emiting the insn. This is useful for icount
and also for embedding fault information for a specific insn.

Backports commit 1d41478fd428e01f057d3248292e4cdcdb048523 from qemu
2018-02-23 19:58:49 -05:00
Sergey Sorokin 98a6d44c54
target-arm: Fix descriptor address masking in ARM address translation
There is a bug in ARM address translation regime with a long-descriptor
format. On the descriptor reading its address is formed from an index
which is a part of the input address. And on the first iteration this index
is incorrectly masked with 'grainsize' mask. But it can be wider according
to pseudo-code.
On the other hand on the iterations other than first the descriptor address
is formed from the previous level descriptor by masking with 'descaddrmask'
value. It always clears just 12 lower bits, but it must clear 'grainsize'
lower bits instead according to pseudo-code.
The patch fixes both cases.

Backports commit dddb5223413c5425ae6eaeb3b967627efc9675f7 from qemu
2018-02-23 19:56:56 -05:00
Sergey Sorokin 00e751f18e
target-arm: Stage 2 permission fault was fixed in AArch32 state
As described in AArch32.CheckS2Permission an instruction fetch fails if
XN bit is set or there is no read permission for the address.

Backports commit dfda68377e20943f474505e75238cb96bc6874bf from qemu
2018-02-23 19:55:11 -05:00
Eric Blake 2f42c2c195
qapi: Change visit_type_FOO() to no longer return partial objects
Returning a partial object on error is an invitation for a careless
caller to leak memory. We already fixed things in an earlier
patch to guarantee NULL if visit_start fails ("qapi: Guarantee
NULL obj on input visitor callback error"), but that does not
help the case where visit_start succeeds but some other failure
happens before visit_end, such that we leak a partially constructed
object outside visit_type_FOO(). As no one outside the testsuite
was actually relying on these semantics, it is cleaner to just
document and guarantee that ALL pointer-based visit_type_FOO()
functions always leave a safe value in *obj during an input visitor
(either the new object on success, or NULL if an error is
encountered), so callers can now unconditionally use
qapi_free_FOO() to clean up regardless of whether an error occurred.

The decision is done by adding visit_is_input(), then updating the
generated code to check if additional cleanup is needed based on
the type of visitor in use.

Note that we still leave *obj unchanged after a scalar-based
visit_type_FOO(); I did not feel like auditing all uses of
visit_type_Enum() to see if the callers would tolerate a specific
sentinel value (not to mention having to decide whether it would
be better to use 0 or ENUM__MAX as that sentinel).

Backports commit 68ab47e4b4ecc1c4649362b8cc1e49794d1a6537 from qemu
2018-02-23 19:53:17 -05:00
Eric Blake 0d52542da2
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:

start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}

Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.

Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.

We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:

start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}

With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).

The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.

The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.

Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.

Backports commit d9f62dde1303286b24ac8ce88be27e2b9b9c5f46 from qemu
2018-02-23 19:50:26 -05:00
Lioncash ed72ba0f8b
qapi: Fix string input visitor handling of invalid list
As shown in the previous commit, the string input visitor was
treating bogus input as an empty list rather than an error.
Fix parse_str() to set errp, then the callers to exit early if
an error was reported.

Meanwhile, fix the testsuite to use the generated
qapi_free_int16List() instead of rolling our own, and to
validate the fixed behavior, while at the same time documenting
one more change that we'd like to make in a later patch (a
failed visit_start_list should guarantee a NULL pointer,
regardless of what things were on input).

Backports commit 74f24cb6306d065045d0e2215a7d10533fa59c57 from qemu
2018-02-23 19:25:26 -05:00
Eric Blake 6084be1882
qapi: Split visit_end_struct() into pieces
As mentioned in previous patches, we want to call visit_end_struct()
functions unconditionally, so that visitors can release resources
tied up since the matching visit_start_struct() without also having
to worry about error priority if more than one error occurs.

Even though error_propagate() can be safely used to ignore a second
error during cleanup caused by a first error, it is simpler if the
cleanup cannot set an error. So, split out the error checking
portion (basically, input visitors checking for unvisited keys) into
a new function visit_check_struct(), which can be safely skipped if
any earlier errors are encountered, and leave the cleanup portion
(which never fails, but must be called unconditionally if
visit_start_struct() succeeded) in visit_end_struct().

Generated code in qapi-visit.c has diffs resembling:

|@@ -59,10 +59,12 @@ void visit_type_ACPIOSTInfo(Visitor *v,
| goto out_obj;
| }
| visit_type_ACPIOSTInfo_members(v, obj, &err);
|- error_propagate(errp, err);
|- err = NULL;
|+ if (err) {
|+ goto out_obj;
|+ }
|+ visit_check_struct(v, &err);
| out_obj:
|- visit_end_struct(v, &err);
|+ visit_end_struct(v);
| out:

and in qapi-event.c:

@@ -47,7 +47,10 @@ void qapi_event_send_acpi_device_ost(ACP
| goto out;
| }
| visit_type_q_obj_ACPI_DEVICE_OST_arg_members(v, &param, &err);
|- visit_end_struct(v, err ? NULL : &err);
|+ if (!err) {
|+ visit_check_struct(v, &err);
|+ }
|+ visit_end_struct(v);
| if (err) {
| goto out;

Backports commit 15c2f669e3fb2bc97f7b42d1871f595c0ac24af8 from qemu
2018-02-23 19:13:47 -05:00
Eric Blake ae8d475ae0
qmp: Tighten output visitor rules
Tighten assertions in the QMP output visitor, so that:

- qmp_output_get_qobject() can only be called after pairing a
visit_end_* for every visit_start_* (rather than allowing it on
a partially built object)

- qmp_output_get_qobject() cannot be called unless at least one
visit_type_* or visit_start/visit_end pair has occurred since
creation/reset (the accidental return of NULL fixed by commit
ab8bf1d7 would have been much easier to diagnose)

- ensure that we are encountering the expected object or list
type, to provide protection against mismatched push(struct)/
pop(list) or push(list)/pop(struct), similar to the qmp-input
protection added in commit bdd8e6b5.

- ensure that except for the root, 'name' is non-null inside a
dict, and NULL inside a list (this may need changing later if
we add "name.0" support for better error messages for a list,
but for now it makes sure all users are at least consistent)

Backports commit 56a6f02b8ce1fe41a2a9077593e46eca7d98267d from qemu
2018-02-23 19:04:41 -05:00
Eric Blake e5b2cff2bd
qmp: Support explicit null during visits
Implement the new type_null() callback for the qmp input and
output visitors. While we don't yet have a use for this in QAPI
input (the generator will need some tweaks first), some
potential usages have already been discussed on the list.
Meanwhile, the output visitor could already output explicit null
via type_any, but this gives us finer control.

At any rate, it's easy to test that we can round-trip an explicit
null through manual use of visit_type_null() wrapped by a virtual
visit_start_struct() walk, even if we can't do the visit in a
QAPI type. Repurpose the test_visitor_out_empty test,
particularly since a future patch will tighten semantics to
forbid use of qmp_output_get_qobject() without at least one
intervening visit_type_*.

Backports commit 3df016f185521f8dfa5bd89168722887156405c7 from qemu
2018-02-23 19:02:18 -05:00
Eric Blake ef6b7b50f6
qapi: Add visit_type_null() visitor
Right now, qmp-output-visitor happens to produce a QNull result
if nothing is actually visited between the creation of the visitor
and the request for the resulting QObject. A stronger protocol
would require that a QMP output visit MUST visit something. But
to still be able to produce a JSON 'null' output, we need a new
visitor function that states our intentions. Yes, we could say
that such a visit must go through visit_type_any(), but that
feels clunky.

So this patch introduces the new visit_type_null() interface and
its no-op interface in the dealloc visitor, and stubs in the
qmp visitors (the next patch will finish the implementation).
For the visitors that will not implement the callback, document
the situation. The code in qapi-visit-core unconditionally
dereferences the callback pointer, so that a segfault will inform
a developer if they need to implement the callback for their
choice of visitor.

Note that JSON has a primitive null type, with the single value
null; likewise with the QNull type for QObject; but for QAPI,
we just have the 'null' value without a null type. We may
eventually want to add more support in QAPI for null (most likely,
we'd use it via an alternate type that permits 'null' or an
object); but we'll create that usage when we need it.

Backports commit 3bc97fd5924561d92f32758c67eaffd2e4e25038 from qemu
2018-02-23 15:48:57 -05:00
Eric Blake fafb3e354b
qapi: Document visitor interfaces, add assertions
The visitor interface for mapping between QObject/QemuOpts/string
and QAPI is scandalously under-documented, making changes to visitor
core, individual visitors, and users of visitors difficult to
coordinate. Among other questions: when is it safe to pass NULL,
vs. when a string must be provided; which visitors implement which
callbacks; the difference between concrete and virtual visits.

Correct this by retrofitting proper contracts, and document where some
of the interface warts remain (for example, we may want to modify
visit_end_* to require the same 'obj' as the visit_start counterpart,
so the dealloc visitor can be simplified). Later patches in this
series will tackle some, but not all, of these warts.

Add assertions to (partially) enforce the contract. Some of these
were only made possible by recent cleanup commits.

Backports commit adfb264c9ed04bfc694921b72173be8e29e90024 from qemu
2018-02-23 15:45:31 -05:00
Eric Blake 9e999acc83
qapi: Change visit_start_implicit_struct to visit_start_alternate
After recent changes, the only remaining use of
visit_start_implicit_struct() is for allocating the space needed
when visiting an alternate. Since the term 'implicit struct' is
hard to explain, rename the function to its current usage. While
at it, we can merge the functionality of visit_get_next_type()
into the same function, making it more like visit_start_struct().

Generated code is now slightly smaller:

| {
| Error *err = NULL;
|
|- visit_start_implicit_struct(v, (void**) obj, sizeof(BlockdevRef), &err);
|+ visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj),
|+ true, &err);
| if (err) {
| goto out;
| }
|- visit_get_next_type(v, name, &(*obj)->type, true, &err);
|- if (err) {
|- goto out_obj;
|- }
| switch ((*obj)->type) {
| case QTYPE_QDICT:
| visit_start_struct(v, name, NULL, 0, &err);
...
| }
|-out_obj:
|- visit_end_implicit_struct(v);
|+ visit_end_alternate(v);
| out:
| error_propagate(errp, err);
| }

Backports commit dbf11922622685934bfb41e7cf2be9bd4a0405c0 from qemu
2018-02-23 15:33:25 -05:00
Eric Blake 5389c1cd5f
qmp-input: Refactor when list is advanced
In the QMP input visitor, visiting a list traverses two objects:
the QAPI GenericList of the caller (which gets advanced in
visit_next_list() regardless of this patch), and the QList input
that we are converting to QAPI. For consistency with QDict
visits, we want to consume elements from the input QList during
the visit_type_FOO() for the list element; that is, we want ALL
the code for consuming an input to live in qmp_input_get_object(),
rather than having it split according to whether we are visiting
a dict or a list. Making qmp_input_get_object() the common point
of consumption will make it easier for a later patch to refactor
visit_start_list() to cover the GenericList * head of a QAPI list,
and in turn will get rid of the 'first' flag (which lived in
qmp_input_next_list() pre-patch, and is hoisted to StackObject
by this patch).

This patch is therefore altering the post-condition use of 'entry',
while keeping what gets visited unchanged, from:

start_list next_list type_ELT ... next_list type_ELT next_list end_list
visits 1st elt last elt
entry NULL 1st elt 1st elt last elt last elt NULL gone

where type_ELT() returns (entry ? entry : 1st elt) and next_list() steps
entry

to this usage:

start_list next_list type_ELT ... next_list type_ELT next_list end_list
visits 1st elt last elt
entry 1st elt 1nd elt 2nd elt last elt NULL NULL gone

where type_ELT() steps entry and returns the old entry, and next_list()
leaves entry alone.

Backports commit fcf3cb21783b2dae3358fdbe7001cb2f74e0cedf from qemu
2018-02-23 15:19:40 -05:00
Eric Blake 68cf25fafa
qmp-input: Require struct push to visit members of top dict
Don't embed the root of the visit into the stack of current
containers being visited. That way, we no longer get confused
on whether the first visit of a dictionary is to the dictionary
itself or to one of the members of the dictionary, based on
whether the caller passed name=NULL; and makes the QMP Input
visitor like other visitors where the value of 'name' is now
ignored on the root visit. (We may someday want to revisit
the rules on what 'name' should be on a top-level visit,
rather than just ignoring it; but that would be the topic of
another patch).

An audit of all qmp_input_visitor_new() call sites shows that
there were only two places where callers had previously been
visiting to a QDict with a non-NULL name to bypass a call to
visit_start_struct(), and those were fixed in prior patches.

Backports commit ce140b176920b5b65184020735a3c65ed3e9aeda from qemu
2018-02-23 15:16:43 -05:00
Eric Blake 1bb4e4c787
qmp-input: Don't consume input when checking has_member
Commit e8316d7 mistakenly passed consume=true within
qmp_input_optional() when checking if an optional member was
present, but the mistake was silently ignored since the code
happily let us extract a member more than once. Fix
qmp_input_optional() to not consume anything, then tighten up
the input visitor to ensure that a member is consumed exactly
once (all generated code follows this pattern; and the new
assert will catch any hand-written code that tries to visit
the same key more than once).

Backports commit e5826a2fd727f0be54a81083f31fe02a275465cd from qemu
2018-02-23 15:12:58 -05:00
Eric Blake cae9c2bd2d
qapi: Use strict QMP input visitor in more places
The following uses of a QMP input visitor should be strict
(that is, excess keys in QDict input should be flagged if not
converted to QAPI):

- Testsuite code unrelated to explicitly testing non-strict
mode (test-qmp-commands, test-visitor-serialization); since
we want more code to be strict by default, having more tests
of strict mode doesn't hurt

- Code used for cloning QAPI objects (replay-input.c,
qemu-sockets.c); we are reparsing a QObject just barely
produced by the qmp output visitor and which therefore should
not have any garbage, so while it is extra work to be strict,
it validates that our clone is correct [note that a later patch
series will simplify these two uses by creating an actual
clone visitor that is much more efficient than a
generate/reparse cycle]

- qmp_object_add(), which calls into user_creatable_add_type().
Since command line parsing for '-object' uses the same
user_creatable_add_type() through the OptsVisitor, and that is
always strict, we want to ensure that any nested dictionaries
would be treated the same in QMP and from the command line (I
don't actually know if such nested dictionaries exist). Note
that on this code change, strictness only matters for nested
dictionaries (if even possible), since we already flag excess
input at the top level during an earlier object_property_set()
on an unknown key, whether from QemuOpts:

$ ./x86_64-softmmu/qemu-system-x86_64 -nographic -nodefaults -qmp stdio -object secret,id=sec0,data=letmein,format=raw,foo=bar
qemu-system-x86_64: -object secret,id=sec0,data=letmein,format=raw,foo=bar: Property '.foo' not found

or from QMP:

$ ./x86_64-softmmu/qemu-system-x86_64 -nographic -nodefaults -qmp stdio
{"QMP": {"version": {"qemu": {"micro": 93, "minor": 5, "major": 2}, "package": ""}, "capabilities": []}}
{"execute":"qmp_capabilities"}
{"return": {}}
{"execute":"object-add","arguments":{"qom-type":"secret","id":"sec0","props":{"format":"raw","data":"letmein","foo":"bar"}}}
{"error": {"class": "GenericError", "desc": "Property '.foo' not found"}}

The only remaining uses of non-strict input visits are:

- QMP 'qom-set' (which eventually executes
object_property_set_qobject()) - mark it as something to revisit
in the future (I didn't want to spend any more time on this patch
auditing if we have any QOM dictionary properties that might be
impacted, and couldn't easily prove whether this code path is
shared with anything else).

- test-qmp-input-visitor: explicit tests of non-strict mode. If
we later get rid of users that don't need strictness, then this
test should be merged with test-qmp-input-strict

Backports relevant parts of commit 240f64b6dc3346d044d7beb7cc3a53668ce47384 from qemu
2018-02-23 15:11:35 -05:00
Eric Blake 559304aed9
qapi: Consolidate QMP input visitor creation
Rather than having two separate ways to create a QMP input
visitor, where the safer approach has the more verbose name,
it is better to consolidate things into a single function
where the caller must explicitly choose whether to be strict
or to ignore excess input. This patch is the strictly
mechanical conversion; the next patch will then audit which
uses can be made stricter.

Backports commit fc471c18d5d2ec713d5a019f9530398675494bc8 from qemu
2018-02-23 15:09:57 -05:00
Eric Blake b1c4558849
qmp-input: Clean up stack handling
Management of the top of stack was a bit verbose; creating a
temporary variable and adding some comments makes the existing
code more legible before the next few patches improve things.
No semantic changes other than asserting that we are always
visiting a QObject, and not a NULL value. In particular, the
check for 'name && qobject_type(qobj) == QTYPE_QDICT)' is a
bit overkill (a dict visit should always have a name); a later
patch revisits that, while this patch is only changing one
layer of indentation due to dropping 'if (qobj)'.

Backports commit b471d012e5d7bec1d2272738141e121b5581fcdf from qemu
2018-02-23 15:08:14 -05:00
Eric Blake 0ec9a5adaf
qapi: Guarantee NULL obj on input visitor callback error
Our existing input visitors were not very consistent on errors in a
function taking 'TYPE **obj'. These are start_struct(),
start_alternate(), type_str(), and type_any(). next_list() is
similar, but can't fail (see commit 08f9541). While all of them set
'*obj' to allocated storage on success, it was not obvious whether
'*obj' was guaranteed safe on failure, or whether it was left
uninitialized. But a future patch wants to guarantee that
visit_type_FOO() does not leak a partially-constructed obj back to
the caller; it is easier to implement this if we can reliably state
that input visitors assign '*obj' regardless of success or failure,
and that on failure *obj is NULL. Add assertions to enforce
consistency in the final setting of err vs. *obj.

The opts-visitor start_struct() doesn't set an error, but it
also was doing a weird check for 0 size; all callers pass in
non-zero size if obj is non-NULL.

The testsuite has at least one spot where we no longer need
to pre-initialize a variable prior to a visit; valgrind confirms
that the test is still fine with the cleanup.

A later patch will document the design constraint implemented
here.

Backports commit e58d695e6c3a5cfa0aa2fc91b87ade017ef28b05 from qemu
2018-02-23 14:53:23 -05:00
Eric Blake 3cf7b6dd3b
qapi: Adjust layout of FooList types
By sticking the next pointer first, we don't need a union with
64-bit padding for smaller types.  On 32-bit platforms, this
can reduce the size of uint8List from 16 bytes (or 12, depending
on whether 64-bit ints can tolerate 4-byte alignment) down to 8.
It has no effect on 64-bit platforms (where alignment still
dictates a 16-byte struct); but fewer anonymous unions is still
a win in my book.

It requires visit_next_list() to gain a size parameter, to know
what size element to allocate; comparable to the size parameter
of visit_start_struct().

I debated about going one step further, to allow for fewer casts,
by doing:
    typedef GenericList GenericList;
    struct GenericList {
        GenericList *next;
    };
    struct FooList {
        GenericList base;
        Foo *value;
    };
so that you convert to 'GenericList *' by '&foolist->base', and
back by 'container_of(generic, GenericList, base)' (as opposed to
the existing '(GenericList *)foolist' and '(FooList *)generic').
But doing that would require hoisting the declaration of
GenericList prior to inclusion of qapi-types.h, rather than its
current spot in visitor.h; it also makes iteration a bit more
verbose through 'foolist->base.next' instead of 'foolist->next'.

Note that for lists of objects, the 'value' payload is still
hidden behind a boxed pointer.  Someday, it would be nice to do:

struct FooList {
    FooList *next;
    Foo value;
};

for one less level of malloc for each list element.  This patch
is a step in that direction (now that 'next' is no longer at a
fixed non-zero offset within the struct, we can store more than
just a pointer's-worth of data as the value payload), but the
actual conversion would be a task for another series, as it will
touch a lot of code.

Backports commit e65d89bf1a4484e0db0f3dc820a8b209f2fb1e8b from qemu
2018-02-23 14:49:06 -05:00
Eric Blake eef0932471
qapi-visit: Add visitor.type classification
We have three classes of QAPI visitors: input, output, and dealloc.
Currently, all implementations of these visitors have one thing in
common based on their visitor type: the implementation used for the
visit_type_enum() callback. But since we plan to add more such
common behavior, in relation to documenting and further refining
the semantics, it makes more sense to have the visitor
implementations advertise which class they belong to, so the common
qapi-visit-core code can use that information in multiple places.

A later patch will better document the types of visitors directly
in visitor.h.

For this patch, knowing the class of a visitor implementation lets
us make input_type_enum() and output_type_enum() become static
functions, by replacing the callback function Visitor.type_enum()
with the simpler enum member Visitor.type. Share a common
assertion in qapi-visit-core as part of the refactoring.

Move comments in opts-visitor.c to match the refactored layout.

Backports commit 983f52d4b3f86fb9dc9f8b142132feb5a8723016 from qemu
2018-02-23 14:25:41 -05:00
Dave Hansen f50acc467f
target-i386: fix typo in xsetbv implementation
QEMU 2.6 added support for the XSAVE family of instructions, which
includes the XSETBV instruction which allows setting the XCR0
register.

But, when booting Linux kernels with XSAVE support enabled, I was
getting very early crashes where the instruction pointer was set
to 0x3. I tracked it down to a jump instruction generated by this:

gen_jmp_im(s->pc - pc_start);

where s->pc is pointing to the instruction after XSETBV and pc_start
is pointing _at_ XSETBV. Subtract the two and you get 0x3. Whoops.

The fix is to replace this typo with the pattern found everywhere
else in the file when folks want to end the translation buffer.

Richard Henderson confirmed that this is a bug and that this is the
correct fix.

Backports commit 502c8e86ea07294067578292c6d402601c196019 from qemu
2018-02-23 14:15:35 -05:00
Fam Zheng 5c739f14f5
util: Fix MIN_NON_ZERO
MIN_NON_ZERO(1, 0) is evaluated to 0. Rewrite the macro to fix it.

Backports commit b6ece2c6f37926a994bc564a9e55ef3be6016d8f from qemu
2018-02-23 14:09:44 -05:00
Artyom Tarasenko 1781d5cfa6
target-sparc: fix register corruption in ldstub if there is no write permission
Backports commit 9566ceeef41ccb5241d340b34776a33450e8f9e5 from qemu
2018-02-23 14:06:38 -05:00
Paolo Bonzini 44c4dd02c9
target-i386: key sfence availability on CPUID_SSE, not CPUID_SSE2
sfence was introduced before lfence and mfence. This fixes Linux
2.4's measurement of checksumming speeds for the pIII_sse
algorithm:

md: linear personality registered as nr 1
md: raid0 personality registered as nr 2
md: raid1 personality registered as nr 3
md: raid5 personality registered as nr 4
raid5: measuring checksumming speed
8regs : 384.400 MB/sec
32regs : 259.200 MB/sec
invalid operand: 0000
CPU: 0
EIP: 0010:[<c0240b2a>] Not tainted
EFLAGS: 00000246
eax: c15d8000 ebx: 00000000 ecx: 00000000 edx: c15d5000
esi: 8005003b edi: 00000004 ebp: 00000000 esp: c15bdf50
ds: 0018 es: 0018 ss: 0018
Process swapper (pid: 1, stackpage=c15bd000)
Stack: 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000
00000000 00000206 c0241c6c 00001000 c15d4000 c15d7000 c15d4000
c15d4000
Call Trace: [<c0241c6c>] [<c0105000>] [<c0241db4>] [<c010503b>]
[<c0105000>]
[<c0107416>] [<c0105030>]

Code: 0f ae f8 0f 10 04 24 0f 10 4c 24 10 0f 10 54 24 20 0f 10 5c
<0>Kernel panic: Attempted to kill init!

Backports commit bd5d278668f33aa08755a982986cd1159746c037 from qemu
2018-02-23 14:03:19 -05:00
Aurelien Jarno 0c4bebb9bc
target-mips: fix call to memset in soft reset code
Recent versions of GCC report the following error when compiling
target-mips/helper.c:

qemu/target-mips/helper.c:542:9: warning: ‘memset’ used with length
equal to number of elements without multiplication by element size
[-Wmemset-elt-size]

Backports commit a525decfaa3449f1458ea2d7a06320cf46aebf3f from qemu
2018-02-23 14:01:50 -05:00
James Hogan e4903fc5f2
target-mips: Fix RDHWR exception host PC
Commit b00c72180c36 ("target-mips: add PC, XNP reg numbers to RDHWR")
changed the rdhwr helpers to use check_hwrena() to check the register
being accessed is enabled in CP0_HWREna when used from user mode. If
that check fails an EXCP_RI exception is raised at the host PC
calculated with GETPC().

However check_hwrena() may not be fully inlined as the
do_raise_exception() part of it is common regardless of the arguments.
This causes GETPC() to calculate the address in the call in the helper
instead of the generated code calling the helper. No TB will be found
and the EPC reported with the resulting guest RI exception points to the
beginning of the TB instead of the RDHWR instruction.

We can't reliably force check_hwrena() to be inlined, and converting it
to a macro would be ugly, so instead pass the host PC in as an argument,
with each rdhwr helper passing GETPC(). This should avoid any dependence
on compiler behaviour, and in practice seems to ensure the full inlining
of check_hwrena() on x86_64.

This issue causes failures when running a MIPS KVM (trap & emulate)
guest in a MIPS QEMU TCG guest, as the inner guest kernel will do a
RDHWR of counter, which is disabled in the outer guest's CP0_HWREna by
KVM so it can emulate the inner guest's counter. The emulation fails and
the RI exception is passed to the inner guest.

Backports commit d96391c1ffeb30a0afa695c86579517c69d9a889 from qemu
2018-02-23 13:59:37 -05:00
Christoffer Dall 6180cbd477
util: align memory allocations to 2M on AArch64
For KVM to use Transparent Huge Pages (THP) we have to ensure that the
alignment of the userspace address of the KVM memory slot and the IPA
that the guest sees for a memory region have the same offset from the 2M
huge page size boundary.

One way to achieve this is to always align the IPA region at a 2M
boundary and ensure that the mmap alignment is also at 2M.

Unfortunately, we were only doing this for __arm__, not for __aarch64__,
so add this simple condition.

This fixes a performance regression using KVM/ARM on AArch64 platforms
that showed a performance penalty of more than 50%, introduced by the
following commit:

9fac18f (oslib: allocate PROT_NONE pages on top of RAM, 2015-09-10)

We were only lucky before the above commit, because we were allocating
large regions and naturally getting a 2M alignment on those allocations
then.

Backports commit ee1e0f8e5d3682c561edcdceccff72b9d9b16d8b from qemu
2018-02-23 13:56:59 -05:00
Aurelien Jarno 6060ab6596
tcg: check for CONFIG_DEBUG_TCG instead of NDEBUG
Check for CONFIG_DEBUG_TCG instead of NDEBUG, drop now useless code.

Backports commit 8d8fdbae010aa75a23f0307172e81034125aba6e from qemu
2018-02-23 13:55:21 -05:00
Aurelien Jarno 355ed7cd08
tcg: use tcg_debug_assert instead of assert (fix performance regression)
The TCG code is quite performance sensitive, but at the same time can
also be quite tricky. That is why asserts that can be enabled with the
--enable-debug-tcg configure option.

This used to work the following way:

| #include "config.h"
|
| ...
|
| #if !defined(CONFIG_DEBUG_TCG) && !defined(NDEBUG)
| /* define it to suppress various consistency checks (faster) */
| #define NDEBUG
| #endif
|
| ...
|
| #include <assert.h>

Since commit 757e725b (tcg: Clean up includes) "config.h" as been
replaced by "qemu/osdep.h" which itself includes <assert.h>. As a
consequence the assertions are always enabled, even when using
--disable-debug-tcg, causing a performance regression, especially on
targets with many registers. For instance on qemu-system-ppc the
speed difference is about 15%.

tcg_debug_assert is controlled directly by CONFIG_DEBUG_TCG and already
uses in some places. This patch replaces all the calls to assert into
calss to tcg_debug_assert.

Backports commit eabb7b91b36b202b4dac2df2d59d698e3aff197a from qemu
2018-02-23 13:52:13 -05:00
Artyom Tarasenko af0e282ab1
target-sparc: fix Trap Based Address Register behavior for sparc64
Accoding the chapter 7.6 Trap Processing of the SPARC Architecture Manual v9,
the Trap Based Address Register is not modified as a trap is taken.

This fix allows booting FreeBSD-10.3-RELEASE-sparc64.

Backports commit de5f1077446ca455342db149737bdc395a7b9882 from qemu
2018-02-23 13:39:59 -05:00
Artyom Tarasenko 34472bd6fd
target-sparc: fix Nucleus quad LDD 128 bit access for windowed registers
Fix register offset calculation when regwptr is used.

Backports commit 01a780d51a3a0851729e1747f3787a0db4d96722 from qemu
2018-02-23 13:39:34 -05:00
Mark Cave-Ayland 7dcdae9807
target-sparc: fix ldstub sign-extension bug
ldstub [addr], reg incorrectly reads a signed byte from memory which causes
problems in the 32-bit Solaris mutex code. Here the byte value being read is
0xff which is incorrectly sign-extended to 0xffffffff before being written back
to the target register causing lock detection to behave incorrectly.

This fixes the intermittent hangs and MUTEX_HELD warnings issued to the
console when running 32-bit Solaris images under qemu-system-sparc.

With thanks to Joseph Dery for providing a condensed test image to consistently
reproduce the problem on demand, and Martin Husemann for allowing me access to
real hardware for comparison.

Backports commit 4553e10360a0713e31647220ed396942f9a6fca0 from qemu
2018-02-23 13:37:36 -05:00
Emilio G. Cota 4cacbf212f
translate-all: add missing fold of tb_ctx into tcg_ctx
Since 5e5f07e08 "TCG: Move translation block variables
to new context inside tcg_ctx: tb_ctx" on Feb 1 2013, compilation
of usermode + TB_DEBUG_CHECK has been broken. Fix it.

Backports commit 7e6bd36d61129feb7f667cb09ffec1b7b54b971c from qemu
2018-02-23 13:35:42 -05:00
Paolo Bonzini bdcea2bcb0
target-i386: check for PKU even for non-writable pages
Xiao Guangrong ran kvm-unit-tests on an actual machine with PKU and
found that it fails:

test pte.p pte.user pde.p pde.user pde.a pde.pse pkru.wd pkey=1 user write efer.nx cr4.pke: FAIL: error code 27 expected 7
Dump mapping: address: 0x123400000000
------L4: 2ebe007
------L3: 2ebf007
------L2: 8000000020000a5

(All failures are combinations of "pde.user pde.p pkru.wd pkey=1",
plus either "pde.pse" or "pte.p pte.user", plus one of "user cr0.wp",
"cr0.wp" or "user", plus unimportant bits such as accessed/dirty or
efer.nx).

So PFEC.PKEY is set even if the ordinary check failed (which it did
because pde.w is zero). Adjust QEMU to match behavior of silicon.

Backports commit 44d066a2f770ee9d61fd1c2a609bdf2a994dfdf7 from qemu
2018-02-23 13:23:37 -05:00
James Hogan 41c6079823
tcg/mips: Fix type of tcg_target_reg_alloc_order[]
The MIPS TCG backend is the only one to have
tcg_target_reg_alloc_order[] elements of type TCGReg rather than int.
This resulted in commit 91478cefaaf2 ("tcg: Allocate indirect_base
temporaries in a different order") breaking the build on MIPS since the
type differed from indirect_reg_alloc_order[]:

tcg/tcg.c:1725:44: error: pointer type mismatch in conditional expression [-Werror]
order = rev ? indirect_reg_alloc_order : tcg_target_reg_alloc_order;
^

Make it an array of ints to fix the build and match other architectures.

Backports commit 2dc7553d0c0a3915c649e1a91b0f0be70b4674b3 from qemu
2018-02-23 13:21:44 -05:00
Lioncash 88af0b0153
target-arm: Get rid of unused variable warnings 2018-02-23 12:43:09 -05:00
Lioncash 87130fc884
exec-all: Remove externs
These are unused
2018-02-23 12:43:03 -05:00
Chen Fan d0621f1852
cpu: Introduce X86CPUTopoInfo structure for argument simplification
In order to simplify arguments of function, introduce a new struct
named X86CPUTopoInfo.

Backports commit ed256144cd6f0ca2ff59fc3fc8dca547506f433b from qemu
2018-02-23 10:58:43 -05:00
Peter Crosthwaite 576f1752a6
include/exec: Move cputlb exec.c defs out
Move the architecture agnostic function prototypes for exec.c out of
cputlb.h to exec-all.h. This allows hiding of the arch specific
cputlb.h from exec.c which should be getting close to having no
architecture specifics. Prepares support for multi-arch, which will have
a minimal cpu.h that services exec.c but not cputlb.h.

Backports commit dfccc7602374c9fd3b083208b552d62daa244811 from qemu
2018-02-23 10:52:25 -05:00
Peter Crosthwaite 97c9423ee8
cputlb: move CPU_LOOP() for tlb_reset() to exec.c
To prepare for multi-arch, cputlb.c should only have awareness of one
single architecture. This means it should not have access to the full
CPU lists which may be heterogeneous. Instead, push the CPU_LOOP() up
to the one and only caller in exec.c.

Backports commit 9a13565d52bfd321934fb44ee004bbaf5f5913a8 from qemu
2018-02-23 10:46:31 -05:00
Lioncash a8085d5a38
uc: Move hook freeing code to its own function
Avoids unrelated variables being in a larger scope than they need to be
2018-02-22 20:00:32 -05:00
Lioncash 7de8b9c67f
uc: Silence unused variable warning 2018-02-22 19:58:08 -05:00
Paolo Bonzini 9479199c6b
memory: fix usage of find_next_bit and find_next_zero_bit
The last two arguments to these functions are the last and first bit to
check relative to the base. The code was using incorrectly the first
bit and the number of bits. Fix this in cpu_physical_memory_get_dirty
and cpu_physical_memory_all_dirty. This requires a few changes in the
iteration; change the code in cpu_physical_memory_set_dirty_range to
match.

Backports commit 88c73d16ad1b6c22a2ab082064d0d521f756296a from qemu
2018-02-22 19:51:43 -05:00
Alex Bennée 171d267209
include/qemu/atomic.h: default to __atomic functions
The __atomic primitives have been available since GCC 4.7 and provide
a richer interface for describing memory ordering requirements. As a
bonus by using the primitives instead of hand-rolled functions we can
use tools such as the ThreadSanitizer which need the use of well
defined APIs for its analysis.

If we have __ATOMIC defines we exclusively use the __atomic primitives
for all our atomic access. Otherwise we fall back to the mixture of
__sync and hand-rolled barrier cases.

Backports commit a0aa44b488b3601415d55041e4619aef5f3a4ba8 from qemu
2018-02-22 16:12:59 -05:00
Paolo Bonzini 4e7259a49b
atomics: add explicit compiler fence in __atomic memory barriers
__atomic_thread_fence does not include a compiler barrier; in the
C++11 memory model, fences take effect in combination with other
atomic operations.  GCC implements this by making __atomic_load and
__atomic_store access memory as if the pointer was volatile, and
leaves no trace whatsoever of acquire and release fences in the
compiler's intermediate representation.

In QEMU, we want memory barriers to act on all memory, but at the same
time we would like to use __atomic_thread_fence for portability reasons.
Add compiler barriers manually around the __atomic_thread_fence.

Backports commit 3bbf572345c65813f86a8fc434ea1b23beb08e16 from qemu
2018-02-22 15:56:37 -05:00
Paolo Bonzini 02e3eeff40
atomic: fix position of volatile qualifier
What needs to be volatile is not the pointer, but the pointed-to
value!

Backports commit 2cbcfb281afa041a41f6e4c4da0f5c9314084604 from qemu
2018-02-22 15:52:48 -05:00
Stefan Hajnoczi e79e0881cd
memory: RCU ram_list.dirty_memory[] for safe RAM hotplug
Although accesses to ram_list.dirty_memory[] use atomics so multiple
threads can safely dirty the bitmap, the data structure is not fully
thread-safe yet.

This patch handles the RAM hotplug case where ram_list.dirty_memory[] is
grown.  ram_list.dirty_memory[] is change from a regular bitmap to an
RCU array of pointers to fixed-size bitmap blocks.  Threads can continue
accessing bitmap blocks while the array is being extended.  See the
comments in the code for an in-depth explanation of struct
DirtyMemoryBlocks.

I have tested that live migration with virtio-blk dataplane works.

Backports commit 5b82b703b69acc67b78b98a5efc897a3912719eb from qemu
2018-02-22 15:38:03 -05:00
Peter Maydell a632d1b96d
target-arm: Make the 64-bit version of VTCR do the migration
Move the ALIAS tag from VTCR_EL2 to VTCR so that we migrate the
64-bit version, as is usual. (This has no particular effect now
unless the guest wrote to the high RES0 bits of VTCR_EL2.)
Add a comment about why it's OK that we don't have the various
accessor functions that the EL1 TCR regdefs do.

Backports commit bf06c1123a427fefc2cf9cf8019578eafc19eb6f from qemu
2018-02-22 11:53:19 -05:00
Peter Maydell a93e873441
target-arm: Remove incorrect ALIAS tags from ESR_EL2 and ESR_EL3
The regdefs for the ESR_EL2 and ESR_EL3 system registers should not
be marked as ARM_CP_ALIAS, because these are the master copies; the
DFSR regdef in vmsa_pmsa_cp_reginfo[] is marked as an alias.
Remove the ALIAS tags so that these registers are correctly migrated.

Backports commit 094a7d0b9d10812d06be2c5c19288cee4603c693 from qemu
2018-02-22 11:40:20 -05:00