QEMU incorrectly validates FEAT_SVM feature flags against
GET_SUPPORTED_CPUID even if SVM features are being masked out by
cpu_x86_cpuid(). This can make QEMU print warnings on most AMD
CPU models, even when SVM nesting is disabled (which is the
default).
This bug was never detected before because of a Linux KVM bug:
until Linux v5.6, KVM was not filtering out SVM features in
GET_SUPPORTED_CPUID when nested was disabled. This KVM bug was
fixed in Linux v5.7-rc1, on Linux commit a50718cc3f43 ("KVM:
nSVM: Expose SVM features to L1 iff nested is enabled").
Fix the problem by adding a CPUID_EXT3_SVM dependency to all
FEAT_SVM feature flags in the feature_dependencies table.
Reported-by: Yanan Fu <yfu@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200623230116.277409-1-ehabkost@redhat.com>
[Fix testcase. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The Linux TSC calibration procedure is subject to small variations
(its common to see +-1 kHz difference between reboots on a given CPU, for example).
So migrating a guest between two hosts with identical processor can fail, in case
of a small variation in calibrated TSC between them.
Allow a conservative 250ppm error between host TSC and VM TSC frequencies,
rather than requiring an exact match. NTP daemon in the guest can
correct this difference.
Also change migration to accept this bound.
KVM_SET_TSC_KHZ depends on a kernel interface change. Without this change,
the behaviour remains the same: in case of a different frequency
between host and VM, KVM_SET_TSC_KHZ will fail and QEMU will exit.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Message-Id: <20200616165805.GA324612@fuller.cnet>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add which features are added or removed in this version.
Signed-off-by: Tao Xu <tao3.xu@intel.com>
Message-Id: <20200324051034.30541-1-tao3.xu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The x87 fpatan emulation is currently based around conversion to
double. This is inherently unsuitable for a good emulation of any
floatx80 operation. Reimplement using the soft-float operations, as
for other such instructions.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2006230000340.24721@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The x87 fyl2x emulation is currently based around conversion to
double. This is inherently unsuitable for a good emulation of any
floatx80 operation. Reimplement using the soft-float operations,
building on top of the reimplementation of fyl2xp1 and factoring out
code to be shared between the two instructions.
The included test assumes that the result in round-to-nearest mode
should always be one of the two closest floating-point numbers to the
mathematically exact result (including that it should be exact, in the
exact cases which cover more cases than for fyl2xp1).
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2006172321530.20587@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The x87 fyl2xp1 emulation is currently based around conversion to
double. This is inherently unsuitable for a good emulation of any
floatx80 operation, even before considering that it is a particularly
naive implementation using double (adding 1 then using log rather than
attempting a better emulation using log1p).
Reimplement using the soft-float operations, as was done for f2xm1; as
in that case, m68k has related operations but not exactly this one and
it seemed safest to implement directly rather than reusing the m68k
code to avoid accumulation of errors.
A test is included with many randomly generated inputs. The
assumption of the test is that the result in round-to-nearest mode
should always be one of the two closest floating-point numbers to the
mathematical value of y * log2(x + 1); the implementation aims to do
somewhat better than that (about 70 correct bits before rounding). I
haven't investigated how accurate hardware is.
Intel manuals describe a narrower range of valid arguments to this
instruction than AMD manuals. The implementation accepts the wider
range (it's needed anyway for the core code to be reusable in a
subsequent patch reimplementing fyl2x), but the test only has inputs
in the narrower range so that it's valid on hardware that may reject
or produce poor results for inputs outside that range.
Code in the previous implementation that sets C2 for some out-of-range
arguments is not carried forward to the new implementation; C2 is
undefined for this instruction and I suspect that code was just
cut-and-pasted from the trigonometric instructions (fcos, fptan, fsin,
fsincos) where C2 *is* defined to be set for out-of-range arguments.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2006172320190.20587@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The x87 fprem and fprem1 emulation is currently based around
conversion to double, which is inherently unsuitable for a good
emulation of any floatx80 operation. Reimplement using the soft-float
floatx80 remainder operations.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <alpine.DEB.2.21.2006081657200.23637@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The x87 f2xm1 emulation is currently based around conversion to
double. This is inherently unsuitable for a good emulation of any
floatx80 operation, even before considering that it is a particularly
naive implementation using double (computing with pow and then
subtracting 1 rather than attempting a better emulation using expm1).
Reimplement using the soft-float operations, including additions and
multiplications with higher precision where appropriate to limit
accumulation of errors. I considered reusing some of the m68k code
for transcendental operations, but the instructions don't generally
correspond exactly to x87 operations (for example, m68k has 2^x and
e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors
from applying multiple such operations each rounding to floatx80
precision, I wrote a direct implementation of 2^x - 1 instead. It
would be possible in principle to make the implementation more
efficient by doing the intermediate operations directly with
significands, signs and exponents and not packing / unpacking floatx80
format for each operation, but that would make it significantly more
complicated and it's not clear that's worthwhile; the m68k emulation
doesn't try to do that.
A test is included with many randomly generated inputs. The
assumption of the test is that the result in round-to-nearest mode
should always be one of the two closest floating-point numbers to the
mathematical value of 2^x - 1; the implementation aims to do somewhat
better than that (about 70 correct bits before rounding). I haven't
investigated how accurate hardware is.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2006112341010.18393@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
All remaining conversions to qdev_realize() are for bus-less devices.
Coccinelle script:
// only correct for bus-less @dev!
@@
expression errp;
expression dev;
@@
- qdev_init_nofail(dev);
+ qdev_realize(dev, NULL, &error_fatal);
@ depends on !(file in "hw/core/qdev.c") && !(file in "hw/core/bus.c")@
expression errp;
expression dev;
symbol true;
@@
- object_property_set_bool(OBJECT(dev), true, "realized", errp);
+ qdev_realize(DEVICE(dev), NULL, errp);
@ depends on !(file in "hw/core/qdev.c") && !(file in "hw/core/bus.c")@
expression errp;
expression dev;
symbol true;
@@
- object_property_set_bool(dev, true, "realized", errp);
+ qdev_realize(DEVICE(dev), NULL, errp);
Note that Coccinelle chokes on ARMSSE typedef vs. macro in
hw/arm/armsse.c. Worked around by temporarily renaming the macro for
the spatch run.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-57-armbru@redhat.com>
The last real change to this file is from 2012, so it is very likely
that this file is completely out-of-date and ignored today. Let's
simply remove it to avoid confusion if someone finds it by accident.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200611172445.5177-1-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SEVState is contained with SevGuestState. We've now fixed redundancies
and name conflicts, so there's no real point to the nested structure. Just
move all the fields of SEVState into SevGuestState.
This eliminates the SEVState structure, which as a bonus removes the
confusion with the SevState enum.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-10-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The user can explicitly specify a handle via the "handle" property wired
to SevGuestState::handle. That gets passed to the KVM_SEV_LAUNCH_START
ioctl() which may update it, the final value being copied back to both
SevGuestState::handle and SEVState::handle.
AFAICT, nothing will be looking SEVState::handle before it and
SevGuestState::handle have been updated from the ioctl(). So, remove the
field and just use SevGuestState::handle directly.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-9-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SEVState::policy is set from the final value of the policy field in the
parameter structure for the KVM_SEV_LAUNCH_START ioctl(). But, AFAICT
that ioctl() won't ever change it from the original supplied value which
comes from SevGuestState::policy.
So, remove this field and just use SevGuestState::policy directly.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-8-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The SEVState structure has cbitpos and reduced_phys_bits fields which are
simply copied from the SevGuestState structure and never changed. Now that
SEVState is embedded in SevGuestState we can just access the original copy
directly.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-7-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The SEV code uses a pretty ugly global to access its internal state. Now
that SEVState is embedded in SevGuestState, we can avoid accessing it via
the global in some cases. In the remaining cases use a new global
referencing the containing SevGuestState which will simplify some future
transformations.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200604064219.436242-6-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently SevGuestState contains only configuration information. For
runtime state another non-QOM struct SEVState is allocated separately.
Simplify things by instead embedding the SEVState structure in
SevGuestState.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200604064219.436242-5-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
At the moment this is a purely passive object which is just a container for
information used elsewhere, hence the name. I'm going to change that
though, so as a preliminary rename it to SevGuestState.
That name risks confusion with both SEVState and SevState, but I'll be
working on that in following patches.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-4-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Neither QSevGuestInfo nor SEVState (not to be confused with SevState) is
used anywhere outside target/i386/sev.c, so they might as well live in
there rather than in a (somewhat) exposed header.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-3-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This structure is nothing but an empty wrapper around the parent class,
which by QOM conventions means we don't need it at all.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-2-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-14-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There's no similar field in CPUX86State, but it's needed for MMIO traps.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-13-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The lazy flags are still needed for instruction decoder.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-12-r.bolshakov@yadro.com>
[Move struct to target/i386/cpu.h - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
HVFX86EmulatorState carries it's own copy of x86 registers. It can be
dropped in favor of regs in generic CPUX86State.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-11-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use the ones provided in target/i386/cpu.h instead.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-10-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
HVFX86EmulatorState carries it's own copy of x86 flags. It can be
dropped in favor of eflags in generic CPUX86State.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-9-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The field is used to print address of instructions that have no parser
in decode_invalid(). RIP from VMCS is saved into fetch_rip before
decoding starts but it's also saved into env->eip in load_regs().
Therefore env->eip can be used instead of fetch_rip.
While at it, correct address printed in decode_invalid(). It prints an
address before the unknown instruction.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-8-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Drop and replace rip field from HVFX86EmulatorState in favor of eip from
common CPUX86State.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-7-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
There's no need to read VMCS twice, instruction length is already
available in ins_len.
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-6-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-5-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
They're either declared elsewhere or have no use.
While at it, rename _hvf_cpu_synchronize_post_init() to
do_hvf_cpu_synchronize_post_init().
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-3-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
"sysemu/hvf.h" is intended for inclusion in generic code. However it
also contains several hvf definitions and declarations, including
HVFState that are used only inside "hvf.c". "hvf-i386.h" would be more
appropriate place to define HVFState as it's only included by "hvf.c"
and "x86_task.c".
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200528193758.51454-2-r.bolshakov@yadro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This corrects a bug introduced in my previous fix for SSE4.2 pcmpestri
/ pcmpestrm / pcmpistri / pcmpistrm substring search, commit
ae35eea7e4.
That commit fixed a bug that showed up in four GCC tests with one libc
implementation. The tests in question generate random inputs to the
intrinsics and compare results to a C implementation, but they only
test 1024 possible random inputs, and when the tests use the cases of
those instructions that work with word rather than byte inputs, it's
easy to have problematic cases that show up much less frequently than
that. Thus, testing with a different libc implementation, and so a
different random number generator, showed up a problem with the
previous patch.
When investigating the previous test failures, I found the description
of these instructions in the Intel manuals (starting from computing a
16x16 or 8x8 set of comparison results) confusing and hard to match up
with the more optimized implementation in QEMU, and referred to AMD
manuals which described the instructions in a different way. Those
AMD descriptions are very explicit that the whole of the string being
searched for must be found in the other operand, not running off the
end of that operand; they say "If the prototype and the SUT are equal
in length, the two strings must be identical for the comparison to be
TRUE.". However, that statement is incorrect.
In my previous commit message, I noted:
The operation in this case is a search for a string (argument d to
the helper) in another string (argument s to the helper); if a copy
of d at a particular position would run off the end of s, the
resulting output bit should be 0 whether or not the strings match in
the region where they overlap, but the QEMU implementation was
wrongly comparing only up to the point where s ends and counting it
as a match if an initial segment of d matched a terminal segment of
s. Here, "run off the end of s" means that some byte of d would
overlap some byte outside of s; thus, if d has zero length, it is
considered to match everywhere, including after the end of s.
The description "some byte of d would overlap some byte outside of s"
is accurate only when understood to refer to overlapping some byte
*within the 16-byte operand* but at or after the zero terminator; it
is valid to run over the end of s if the end of s is the end of the
16-byte operand. So the fix in the previous patch for the case of d
being empty was correct, but the other part of that patch was not
correct (as it never allowed partial matches even at the end of the
16-byte operand). Nor was the code before the previous patch correct
for the case of d nonempty, as it would always have allowed partial
matches at the end of s.
Fix with a partial revert of my previous change, combined with
inserting a check for the special case of s having maximum length to
determine where it is necessary to check for matches.
In the added test, test 1 is for the case of empty strings, which
failed before my 2017 patch, test 2 is for the bug introduced by my
2017 patch and test 3 deals with the case where a match of an initial
segment at the end of the string is not valid when the string ends
before the end of the 16-byte operand (that is, the case that would be
broken by a simple revert of the non-empty-string part of my 2017
patch).
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2006121344290.9881@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Most x87 instruction implementations fail to raise the expected IEEE
floating-point exceptions because they do nothing to convert the
exception state from the softfloat machinery into the exception flags
in the x87 status word. There is special-case handling of division to
raise the divide-by-zero exception, but that handling is itself buggy:
it raises the exception in inappropriate cases (inf / 0 and nan / 0,
which should not raise any exceptions, and 0 / 0, which should raise
"invalid" instead).
Fix this by converting the floating-point exceptions raised during an
operation by the softfloat machinery into exceptions in the x87 status
word (passing through the existing fpu_set_exception function for
handling related to trapping exceptions). There are special cases
where some functions convert to integer internally but exceptions from
that conversion are not always correct exceptions for the instruction
to raise.
There might be scope for some simplification if the softfloat
exception state either could always be assumed to be in sync with the
state in the status word, or could always be ignored at the start of
each instruction and just set to 0 then; I haven't looked into that in
detail, and it might run into interactions with the various ways the
emulation does not yet handle trapping exceptions properly. I think
the approach taken here, of saving the softfloat state, setting
exceptions there to 0 and then merging the old exceptions back in
after carrying out the operation, is conservatively safe.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005152120280.3469@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The Perfmon and Debug Capability MSR named IA32_PERF_CAPABILITIES is
a feature-enumerating MSR, which only enumerates the feature full-width
write (via bit 13) by now which indicates the processor supports IA32_A_PMCx
interface for updating bits 32 and above of IA32_PMCx.
The existence of MSR IA32_PERF_CAPABILITIES is enumerated by CPUID.1:ECX[15].
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: qemu-devel@nongnu.org
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Message-Id: <20200529074347.124619-5-like.xu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit acb9f95a removed boundary checks for ID and VCPU ID. After that,
the max definitions of that boundaries are not required anymore. This
commit is only a code cleanup.
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Message-Id: <20200323200538.202164-1-jcfaracco@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AVX512_VP2INTERSECT compute vector pair intersection to a pair
of mask registers, which is introduced with intel Tiger Lake,
defining as CPUID.(EAX=7,ECX=0):EDX[bit 08].
Refer to the following release spec:
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Signed-off-by: Cathy Zhang <cathy.zhang@intel.com>
Message-Id: <1586760758-13638-1-git-send-email-cathy.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fist / fistt family of instructions should all store the most
negative integer in the destination format when the rounded /
truncated integer result is out of range or the input is an invalid
encoding, infinity or NaN. The fisttpl and fisttpll implementations
(32-bit and 64-bit results, truncate towards zero) failed to do this,
producing the most positive integer in some cases instead. Fix this
by copying the code used to handle this issue for fistpl and fistpll,
adjusted to use the _round_to_zero functions for the actual
conversion (but without any other changes to that code).
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005152119160.3469@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fbstp implementation fails to check for out-of-range and invalid
values, instead just taking the result of conversion to int64_t and
storing its sign and low 18 decimal digits. Fix this by checking for
an out-of-range result (invalid conversions always result in INT64_MAX
or INT64_MIN from the softfloat code, which are large enough to be
considered as out-of-range by this code) and storing the packed BCD
indefinite encoding in that case.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005132351110.11687@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fbstp implementation stores +0 when the rounded result should be
-0 because it compares an integer value with 0 to determine the sign.
Fix this by checking the sign bit of the operand instead.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005132350230.11687@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fxam implementation does not check for invalid encodings, instead
treating them like NaN or normal numbers depending on the exponent.
Fix it to check that the high bit of the significand is set before
treating an encoding as NaN or normal, thus resulting in correct
handling (all of C0, C2 and C3 cleared) for invalid encodings.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005132349311.11687@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The implementations of the fldl2t, fldl2e, fldpi, fldlg2 and fldln2
instructions load fixed constants independent of the rounding mode.
Fix them to load a value correctly rounded for the current rounding
mode (but always rounded to 64-bit precision independent of the
precision control, and without setting "inexact") as specified.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <alpine.DEB.2.21.2005132348310.11687@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fscale implementation uses floatx80_scalbn for the final scaling
operation. floatx80_scalbn ends up rounding the result using the
dynamic rounding precision configured for the FPU. But only a limited
set of x87 floating-point instructions are supposed to respect the
dynamic rounding precision, and fscale is not in that set. Fix the
implementation to save and restore the rounding precision around the
call to floatx80_scalbn.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005070045430.18350@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fscale implementation passes infinite exponents through to generic
code that rounds the exponent to a 32-bit integer before using
floatx80_scalbn. In round-to-nearest mode, and ignoring exceptions,
this works in many cases. But it fails to handle the special cases of
scaling 0 by a +Inf exponent or an infinity by a -Inf exponent, which
should produce a NaN, and because it produces an inexact result for
finite nonzero numbers being scaled, the result is sometimes incorrect
in other rounding modes. Add appropriate handling of infinite
exponents to produce a NaN or an appropriately signed exact zero or
infinity as a result.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005070045010.18350@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The fscale implementation does not check for invalid encodings in the
exponent operand, thus treating them like INT_MIN (the value returned
for invalid encodings by floatx80_to_int32_round_to_zero). Fix it to
treat them similarly to signaling NaN exponents, thus generating a
quiet NaN result.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005070044190.18350@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The implementation of the fscale instruction returns a NaN exponent
unchanged. Fix it to return a quiet NaN when the provided exponent is
a signaling NaN.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005070043330.18350@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The implementation of the fxtract instruction treats all nonzero
operands as normal numbers, so yielding incorrect results for invalid
formats, infinities, NaNs and subnormal and pseudo-denormal operands.
Implement appropriate handling of all those cases.
Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <alpine.DEB.2.21.2005070042360.18350@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When we hotplug vcpus, cpu_update_state is added to vm_change_state_head
in kvm_arch_init_vcpu(). But it forgot to delete in kvm_arch_destroy_vcpu() after
unplug. Then it will cause a use-after-free access. This patch delete it in
kvm_arch_destroy_vcpu() to fix that.
Reproducer:
virsh setvcpus vm1 4 --live
virsh setvcpus vm1 2 --live
virsh suspend vm1
virsh resume vm1
The UAF stack:
==qemu-system-x86_64==28233==ERROR: AddressSanitizer: heap-use-after-free on address 0x62e00002e798 at pc 0x5573c6917d9e bp 0x7fff07139e50 sp 0x7fff07139e40
WRITE of size 1 at 0x62e00002e798 thread T0
#0 0x5573c6917d9d in cpu_update_state /mnt/sdb/qemu/target/i386/kvm.c:742
#1 0x5573c699121a in vm_state_notify /mnt/sdb/qemu/vl.c:1290
#2 0x5573c636287e in vm_prepare_start /mnt/sdb/qemu/cpus.c:2144
#3 0x5573c6362927 in vm_start /mnt/sdb/qemu/cpus.c:2150
#4 0x5573c71e8304 in qmp_cont /mnt/sdb/qemu/monitor/qmp-cmds.c:173
#5 0x5573c727cb1e in qmp_marshal_cont qapi/qapi-commands-misc.c:835
#6 0x5573c7694c7a in do_qmp_dispatch /mnt/sdb/qemu/qapi/qmp-dispatch.c:132
#7 0x5573c7694c7a in qmp_dispatch /mnt/sdb/qemu/qapi/qmp-dispatch.c:175
#8 0x5573c71d9110 in monitor_qmp_dispatch /mnt/sdb/qemu/monitor/qmp.c:145
#9 0x5573c71dad4f in monitor_qmp_bh_dispatcher /mnt/sdb/qemu/monitor/qmp.c:234
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200513132630.13412-1-pannengyuan@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Dynamic allocating vcpu state structure according to smp value to be
more precise and safe. Previously it will alloccate array of fixed size
HAX_MAX_VCPU.
This is achieved by using g_new0 to dynamic allocate the array. The
allocated size is obtained from smp.max_cpus in MachineState. Also, the
size is compared with HAX_MAX_VCPU when creating the vm. The reason for
choosing dynamic array over linked list is because the status is visited
by index all the time.
This will lead to QEMU checking whether the smp value is larger than the
HAX_MAX_VCPU when creating vm, if larger, the process will terminate,
otherwise it will allocate array of size smp to store the status.
V2: Check max_cpus before open vm. (Philippe)
Signed-off-by: WangBowen <bowen.wang@intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Message-Id: <20200509035952.187615-1-colin.xu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This code is not related to hardware emulation.
Move it under accel/ with the other hypervisors.
Reviewed-by: Paul Durrant <paul@xen.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200508100222.7112-1-philmd@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
