We want all accelerators to share the same opaque pointer in
CPUState. Rename WHPX 'whpx_vcpu' as 'AccelCPUState'; use
the typedef.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-14-philmd@linaro.org>
No need for this helper to access the CPUState::accel field.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230624174121.11508-12-philmd@linaro.org>
We want all accelerators to share the same opaque pointer in
CPUState. Rename NVMM 'qemu_vcpu' as 'AccelCPUState'; directly
use the typedef, remove unnecessary casts.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230624174121.11508-11-philmd@linaro.org>
hThread variable is only used by the HAX accelerator,
so move it to the accelerator specific context.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-9-philmd@linaro.org>
We want all accelerators to share the same opaque pointer in
CPUState. Start with the HAX context, renaming its forward
declarated structure 'hax_vcpu_state' as 'AccelCPUState'.
Document the CPUState field. Directly use the typedef.
Remove the amusing but now unnecessary casts in NVMM / WHPX.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-8-philmd@linaro.org>
All accelerators will share a single opaque context
in CPUState. Start by renaming 'hax_vcpu' as 'accel'.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230624174121.11508-7-philmd@linaro.org>
When the vCPU thread finished its processing, destroy
it and signal its destruction to generic vCPU management
layer.
Add a sanity check for the vCPU accelerator context.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-6-philmd@linaro.org>
hThread is only used on the error path in hax_kick_vcpu_thread().
Fixes: b0cb0a66d6 ("Plumb the HAXM-based hardware acceleration support")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-5-philmd@linaro.org>
On Windows hosts, cpu->hThread is assigned but never accessed:
remove it.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-4-philmd@linaro.org>
Since MinGW commit 395dcfdea ("rename hyper-v headers and def
files to lower case") [*], WinHvPlatform.h and WinHvEmulation.h
got respectively renamed as winhvplatform.h / winhvemulation.h.
The mingw64-headers package included in the Fedora version we
use for CI does include this commit; and meson fails to detect
these present-but-renamed headers while cross-building (on
case-sensitive filesystems).
Use the renamed header in order to detect and successfully
cross-build with the WHPX accelerator.
Note, on Windows hosts, the libraries are still named as
WinHvPlatform.dll and WinHvEmulation.dll, so we don't bother
renaming the definitions used by load_whp_dispatch_fns() in
target/i386/whpx/whpx-all.c.
[*] https://sourceforge.net/p/mingw-w64/mingw-w64/ci/395dcfdea
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230624142211.8888-3-philmd@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621135633.1649-4-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
AMD supports both 32-bit and 64-bit SYSCALL/SYSRET, but the TCG only
exposes it for 64-bit targets. For system emulation just reuse the
helper; for user-mode emulation the ABI is the same as "int $80".
The BSDs does not support any fast system call mechanism in 32-bit
mode so add to bsd-user the same stub that FreeBSD has for 64-bit
compatibility mode.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
RDPID corresponds to a RDMSR(TSC_AUX); however, it is unprivileged
so for user-mode emulation we must provide the value that the kernel
places in the MSR. For Linux, it is a combination of the current CPU
and the current NUMA node, both of which can be retrieved with getcpu(2).
Also try sched_getcpu(), which might be there on the BSDs. If there is
no portable way to retrieve the current CPU id from userspace, return 0.
RDTSCP is reimplemented as RDTSC + RDPID ECX; the differences in terms
of serializability are not relevant to QEMU.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
WBNOINVD is the same as INVD or WBINVD as far as TCG is concerned,
since there is no cache in TCG and therefore no invalidation side effect
in WBNOINVD.
With respect to SVM emulation, processors that do not support WBNOINVD
will ignore the prefix and treat it as WBINVD, while those that support
it will generate exactly the same vmexit.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
XSAVEERPTR is actually a fix for an errata; TCG does not have the issue.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
TCG implements RDSEED, and in fact uses qcrypto_random_bytes which is
secure enough to match hardware behavior. Expose it to guests.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The AMD prefetch(w) instructions have not been deprecated together with the rest
of 3DNow!, and in fact are even supported by newer Intel processor. Mark them
as supported by TCG, as it supports all of 3DNow!.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Due to a typo or perhaps a brain fart, the INVD vmexit was never generated.
Fix it (but not that fixing just the typo would break both INVD and WBINVD,
due to a case of two wrongs making a right).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We use the user_ss[] array to hold the user emulation sources,
and the softmmu_ss[] array to hold the system emulation ones.
Hold the latter in the 'system_ss[]' array for parity with user
emulation.
Mechanical change doing:
$ sed -i -e s/softmmu_ss/system_ss/g $(git grep -l softmmu_ss)
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230613133347.82210-10-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since we *might* have user emulation with softmmu,
use the clearer 'CONFIG_SYSTEM_ONLY' key to check
for system emulation.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230613133347.82210-9-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since cpu_mmu_index() is well-defined for user-only,
we can remove the surrounding #ifdef'ry entirely.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230613133347.82210-2-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since commit 139c1837db ("meson: rename included C source files
to .c.inc"), QEMU standard procedure for included C files is to
use *.c.inc.
Besides, since commit 6a0057aa22 ("docs/devel: make a statement
about includes") this is documented as the Coding Style:
If you do use template header files they should be named with
the ``.c.inc`` or ``.h.inc`` suffix to make it clear they are
being included for expansion.
Therefore move the included templates in the tcg/ directory and
rename as '.h.inc'.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230608133108.72655-5-philmd@linaro.org>
Move the #ifdef'ry inside do_cpu_init() instead of
declaring an empty stub for user emulation.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230602224628.59546-3-philmd@linaro.org>
Since commit 604664726f ("target/i386: Restrict cpu_exec_interrupt()
handler to sysemu"), do_cpu_sipi() isn't called anymore on user
emulation. Remove the now pointless stub.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230602224628.59546-2-philmd@linaro.org>
Guests can now be debugged through the gdbstub. Support is added for
single-stepping, software breakpoints, hardware breakpoints and
watchpoints. The code has been structured like the KVM counterpart.
While guest debugging is enabled, the guest can still read and write the
DBG*_EL1 registers but they don't have any effect.
Signed-off-by: Francesco Cagnin <fcagnin@quarkslab.com>
Message-id: 20230601153107.81955-5-fcagnin@quarkslab.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Required for guest debugging. The code has been structured like the KVM
counterpart.
Signed-off-by: Francesco Cagnin <fcagnin@quarkslab.com>
Message-id: 20230601153107.81955-4-fcagnin@quarkslab.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
New wrapper around gen_io_start which takes care of the USE_ICOUNT
check, as well as marking the DisasContext to end the TB.
Remove exec/gen-icount.h.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This will enable replacement of TARGET_INSN_START_WORDS in tcg.c.
Split out "tcg/insn-start-words.h" and use it in target/.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for compiling tcg/ only once, eliminate
the all_helpers array. Instantiate the info structs for
the generic helpers in accel/tcg/, and the structs for
the target-specific helpers in each translate.c.
Since we don't see all of the info structs at startup,
initialize at first use, using g_once_init_* to make
sure we don't race while doing so.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been pulled in from exec/cpu_ldst.h, via exec/exec-all.h,
but the include of tcg.h will be removed.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Based on the kernel commit "b0563468ee x86/CPU/AMD: Disable XSAVES on
AMD family 0x17", host system with EPYC-Rome can clear XSAVES capability
bit. In another words, EPYC-Rome host without XSAVES can occur. Thus, we
need an EPYC-Rome cpu model (without this feature) that matches the
solution of fixing this erratum
Signed-off-by: Maksim Davydov <davydov-max@yandex-team.ru>
Message-Id: <20230524213748.8918-1-davydov-max@yandex-team.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before this change, MOVNTPS and MOVNTPD were labeled as Exception Class
4 (only requiring alignment for legacy SSE instructions). This changes
them to Exception Class 1 (always requiring memory alignment), as
documented in the Intel manual.
Message-Id: <20230501111428.95998-3-ricky@rzhou.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fix the exception classes for some SSE/AVX instructions to match what is
documented in the Intel manual.
These changes are expected to have no functional effect on the behavior
that qemu implements (primarily >= 16-byte memory alignment checks). For
instance, since qemu does not implement the AC flag, there is no
difference in behavior between Exception Classes 4 and 5 for
instructions where the SSE version only takes <16 byte memory operands.
Message-Id: <20230501111428.95998-2-ricky@rzhou.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Adds some comments describing what instructions correspond to decoding
table entries and fixes some existing comments which named the wrong
instruction.
Message-Id: <20230501111428.95998-1-ricky@rzhou.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
vzeroall: xmm_regs should be used instead of xmm_t0
vpermdq: bit 3 and 7 of imm should be considered
Signed-off-by: Xinyu Li <lixinyu20s@ict.ac.cn>
Message-Id: <20230510145222.586487-1-lixinyu20s@ict.ac.cn>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Compared to other SSE instructions, VUCOMISx and VCOMISx are different:
the single and double precision versions are distinguished through a
prefix, however they use no-prefix and 0x66 for SS and SD respectively.
Scalar values usually are associated with 0xF2 and 0xF3.
Because of these, they incorrectly perform a 128-bit memory load instead
of a 32- or 64-bit load. Fix this by writing a custom decoding function.
I tested that the reproducer is fixed and the test-avx output does not
change.
Reported-by: Gabriele Svelto <gsvelto@mozilla.com>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1637
Fixes: f8d19eec0d ("target/i386: reimplement 0x0f 0x28-0x2f, add AVX", 2022-10-18)
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As reported by the Intel's doc:
"FB_CLEAR: The processor will overwrite fill buffer values as part of
MD_CLEAR operations with the VERW instruction.
On these processors, L1D_FLUSH does not overwrite fill buffer values."
If this cpu feature is present in host, allow QEMU to choose whether to
show it to the guest too.
One disadvantage of not exposing it is that the guest will report
a non existing vulnerability in
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
because the mitigation is present only when the cpu has
(FLUSH_L1D and MD_CLEAR) or FB_CLEAR
features enabled.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201135759.555607-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As reported by Intel's doc:
"L1D_FLUSH: Writeback and invalidate the L1 data cache"
If this cpu feature is present in host, allow QEMU to choose whether to
show it to the guest too.
One disadvantage of not exposing it is that the guest will report
a non existing vulnerability in
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
because the mitigation is present only when the cpu has
(FLUSH_L1D and MD_CLEAR) or FB_CLEAR
features enabled.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201135759.555607-2-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Adds the support for AMD EPYC Genoa generation processors. The model
display for the new processor will be EPYC-Genoa.
Adds the following new feature bits on top of the feature bits from
the previous generation EPYC models.
avx512f : AVX-512 Foundation instruction
avx512dq : AVX-512 Doubleword & Quadword Instruction
avx512ifma : AVX-512 Integer Fused Multiply Add instruction
avx512cd : AVX-512 Conflict Detection instruction
avx512bw : AVX-512 Byte and Word Instructions
avx512vl : AVX-512 Vector Length Extension Instructions
avx512vbmi : AVX-512 Vector Byte Manipulation Instruction
avx512_vbmi2 : AVX-512 Additional Vector Byte Manipulation Instruction
gfni : AVX-512 Galois Field New Instructions
avx512_vnni : AVX-512 Vector Neural Network Instructions
avx512_bitalg : AVX-512 Bit Algorithms, add bit algorithms Instructions
avx512_vpopcntdq: AVX-512 AVX-512 Vector Population Count Doubleword and
Quadword Instructions
avx512_bf16 : AVX-512 BFLOAT16 instructions
la57 : 57-bit virtual address support (5-level Page Tables)
vnmi : Virtual NMI (VNMI) allows the hypervisor to inject the NMI
into the guest without using Event Injection mechanism
meaning not required to track the guest NMI and intercepting
the IRET.
auto-ibrs : The AMD Zen4 core supports a new feature called Automatic IBRS.
It is a "set-and-forget" feature that means that, unlike e.g.,
s/w-toggled SPEC_CTRL.IBRS, h/w manages its IBRS mitigation
resources automatically across CPL transitions.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <20230504205313.225073-8-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the following featute bits.
vnmi: Virtual NMI (VNMI) allows the hypervisor to inject the NMI into the
guest without using Event Injection mechanism meaning not required to
track the guest NMI and intercepting the IRET.
The presence of this feature is indicated via the CPUID function
0x8000000A_EDX[25].
automatic-ibrs :
The AMD Zen4 core supports a new feature called Automatic IBRS.
It is a "set-and-forget" feature that means that, unlike e.g.,
s/w-toggled SPEC_CTRL.IBRS, h/w manages its IBRS mitigation
resources automatically across CPL transitions.
The presence of this feature is indicated via the CPUID function
0x80000021_EAX[8].
The documention for the features are available in the links below.
a. Processor Programming Reference (PPR) for AMD Family 19h Model 01h,
Revision B1 Processors
b. AMD64 Architecture Programmer’s Manual Volumes 1–5 Publication No. Revision
40332 4.05 Date October 2022
Signed-off-by: Santosh Shukla <santosh.shukla@amd.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Link: https://www.amd.com/system/files/TechDocs/55898_B1_pub_0.50.zip
Link: https://www.amd.com/system/files/TechDocs/40332_4.05.pdf
Message-Id: <20230504205313.225073-7-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the following feature bits for EPYC-Milan model and bump the version.
vaes : Vector VAES(ENC|DEC), VAES(ENC|DEC)LAST instruction support
vpclmulqdq : Vector VPCLMULQDQ instruction support
stibp-always-on : Single Thread Indirect Branch Prediction Mode has enhanced
performance and may be left Always on
amd-psfd : Predictive Store Forward Disable
no-nested-data-bp : Processor ignores nested data breakpoints
lfence-always-serializing : LFENCE instruction is always serializing
null-sel-clr-base : Null Selector Clears Base. When this bit is
set, a null segment load clears the segment base
These new features will be added in EPYC-Milan-v2. The "-cpu help" output
after the change will be.
x86 EPYC-Milan (alias configured by machine type)
x86 EPYC-Milan-v1 AMD EPYC-Milan Processor
x86 EPYC-Milan-v2 AMD EPYC-Milan Processor
The documentation for the features are available in the links below.
a. Processor Programming Reference (PPR) for AMD Family 19h Model 01h,
Revision B1 Processors
b. SECURITY ANALYSIS OF AMD PREDICTIVE STORE FORWARDING
c. AMD64 Architecture Programmer’s Manual Volumes 1–5 Publication No. Revision
40332 4.05 Date October 2022
Signed-off-by: Babu Moger <babu.moger@amd.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://www.amd.com/system/files/TechDocs/55898_B1_pub_0.50.zip
Link: https://www.amd.com/system/files/documents/security-analysis-predictive-store-forwarding.pdf
Link: https://www.amd.com/system/files/TechDocs/40332_4.05.pdf
Message-Id: <20230504205313.225073-6-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the following feature bits.
no-nested-data-bp : Processor ignores nested data breakpoints.
lfence-always-serializing : LFENCE instruction is always serializing.
null-sel-cls-base : Null Selector Clears Base. When this bit is
set, a null segment load clears the segment base.
The documentation for the features are available in the links below.
a. Processor Programming Reference (PPR) for AMD Family 19h Model 01h,
Revision B1 Processors
b. AMD64 Architecture Programmer’s Manual Volumes 1–5 Publication No. Revision
40332 4.05 Date October 2022
Signed-off-by: Babu Moger <babu.moger@amd.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://www.amd.com/system/files/TechDocs/55898_B1_pub_0.50.zip
Link: https://www.amd.com/system/files/TechDocs/40332_4.05.pdf
Message-Id: <20230504205313.225073-5-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the following feature bits.
amd-psfd : Predictive Store Forwarding Disable:
PSF is a hardware-based micro-architectural optimization
designed to improve the performance of code execution by
predicting address dependencies between loads and stores.
While SSBD (Speculative Store Bypass Disable) disables both
PSF and speculative store bypass, PSFD only disables PSF.
PSFD may be desirable for the software which is concerned
with the speculative behavior of PSF but desires a smaller
performance impact than setting SSBD.
Depends on the following kernel commit:
b73a54321ad8 ("KVM: x86: Expose Predictive Store Forwarding Disable")
stibp-always-on :
Single Thread Indirect Branch Prediction mode has enhanced
performance and may be left always on.
The documentation for the features are available in the links below.
a. Processor Programming Reference (PPR) for AMD Family 19h Model 01h,
Revision B1 Processors
b. SECURITY ANALYSIS OF AMD PREDICTIVE STORE FORWARDING
Signed-off-by: Babu Moger <babu.moger@amd.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://www.amd.com/system/files/documents/security-analysis-predictive-store-forwarding.pdf
Link: https://www.amd.com/system/files/TechDocs/55898_B1_pub_0.50.zip
Message-Id: <20230504205313.225073-4-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce new EPYC cpu versions: EPYC-v4 and EPYC-Rome-v3.
The only difference vs. older models is an updated cache_info with
the 'complex_indexing' bit unset, since this bit is not currently
defined for AMD and may cause problems should it be used for
something else in the future. Setting this bit will also cause
CPUID validation failures when running SEV-SNP guests.
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20230504205313.225073-3-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
New EPYC CPUs versions require small changes to their cache_info's.
Because current QEMU x86 CPU definition does not support versioned
cach_info, we would have to declare a new CPU type for each such case.
To avoid the dup work, add "cache_info" in X86CPUVersionDefinition",
to allow new cache_info pointers to be specified for a new CPU version.
Co-developed-by: Wei Huang <wei.huang2@amd.com>
Signed-off-by: Wei Huang <wei.huang2@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20230504205313.225073-2-babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Latest Intel platform Granite Rapids has introduced a new instruction -
PREFETCHIT0/1, which moves code to memory (cache) closer to the
processor depending on specific hints.
The bit definition:
CPUID.(EAX=7,ECX=1):EDX[bit 14]
Add CPUID definition for PREFETCHIT0/1.
Signed-off-by: Jiaxi Chen <jiaxi.chen@linux.intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20230303065913.1246327-7-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AVX-NE-CONVERT is a new set of instructions which can convert low
precision floating point like BF16/FP16 to high precision floating point
FP32, as well as convert FP32 elements to BF16. This instruction allows
the platform to have improved AI capabilities and better compatibility.
The bit definition:
CPUID.(EAX=7,ECX=1):EDX[bit 5]
Add CPUID definition for AVX-NE-CONVERT.
Signed-off-by: Jiaxi Chen <jiaxi.chen@linux.intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20230303065913.1246327-6-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AVX-VNNI-INT8 is a new set of instructions in the latest Intel platform
Sierra Forest, aims for the platform to have superior AI capabilities.
This instruction multiplies the individual bytes of two unsigned or
unsigned source operands, then adds and accumulates the results into the
destination dword element size operand.
The bit definition:
CPUID.(EAX=7,ECX=1):EDX[bit 4]
AVX-VNNI-INT8 is on a new feature bits leaf. Add a CPUID feature word
FEAT_7_1_EDX for this leaf.
Add CPUID definition for AVX-VNNI-INT8.
Signed-off-by: Jiaxi Chen <jiaxi.chen@linux.intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20230303065913.1246327-5-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AVX-IFMA is a new instruction in the latest Intel platform Sierra
Forest. This instruction packed multiplies unsigned 52-bit integers and
adds the low/high 52-bit products to Qword Accumulators.
The bit definition:
CPUID.(EAX=7,ECX=1):EAX[bit 23]
Add CPUID definition for AVX-IFMA.
Signed-off-by: Jiaxi Chen <jiaxi.chen@linux.intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20230303065913.1246327-4-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Latest Intel platform Granite Rapids has introduced a new instruction -
AMX-FP16, which performs dot-products of two FP16 tiles and accumulates
the results into a packed single precision tile. AMX-FP16 adds FP16
capability and allows a FP16 GPU trained model to run faster without
loss of accuracy or added SW overhead.
The bit definition:
CPUID.(EAX=7,ECX=1):EAX[bit 21]
Add CPUID definition for AMX-FP16.
Signed-off-by: Jiaxi Chen <jiaxi.chen@linux.intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20230303065913.1246327-3-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CMPccXADD is a new set of instructions in the latest Intel platform
Sierra Forest. This new instruction set includes a semaphore operation
that can compare and add the operands if condition is met, which can
improve database performance.
The bit definition:
CPUID.(EAX=7,ECX=1):EAX[bit 7]
Add CPUID definition for CMPCCXADD.
Signed-off-by: Jiaxi Chen <jiaxi.chen@linux.intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20230303065913.1246327-2-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Update the setting of CPUID 0x8000001F EBX to clearly document the ranges
associated with fields being set.
Fixes: 6cb8f2a663 ("cpu/i386: populate CPUID 0x8000_001F when SEV is active")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <5822fd7d02b575121380e1f493a8f6d9eba2b11a.1664550870.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The value of the reduced-phys-bits parameter is propogated to the CPUID
information exposed to the guest. Update the current validation check to
account for the size of the CPUID field (6-bits), ensuring the value is
in the range of 1 to 63.
Maintain backward compatibility, to an extent, by allowing a value greater
than 1 (so that the previously documented value of 5 still works), but not
allowing anything over 63.
Fixes: d8575c6c02 ("sev/i386: add command to initialize the memory encryption context")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <cca5341a95ac73f904e6300f10b04f9c62e4e8ff.1664550870.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We want to get rid of the "#ifdef TARGET_X86_64" compile-time switch
in the long run, so we can drop the separate compilation of the
"qemu-system-i386" binary one day - but we then still need a way to
run a guest with max. CPU settings in 32-bit mode. So the "max" CPU
should determine its family/model/stepping settings according to the
"large mode" (LM) CPU feature bit during runtime, so that it is
possible to run "qemu-system-x86_64 -cpu max,lm=off" and still get
a sane family/model/stepping setting for the guest CPU.
To be able to check the LM bit, we have to move the code that sets
up these properties to a "realize" function, since the LM setting is
not available yet when the "instance_init" function is being called.
Message-Id: <20230306154311.476458-1-thuth@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
The previous patch wrongly replaced FEAT_XSAVE_XCR0_{LO|HI} with
FEAT_XSAVE_XSS_{LO|HI} in CPUID(EAX=12,ECX=1):{ECX,EDX}. As a result,
SGX enclaves only supported SSE and x87 feature (xfrm=0x3).
Fixes: 301e90675c ("target/i386: Enable support for XSAVES based features")
Signed-off-by: Yang Zhong <yang.zhong@linux.intel.com>
Reviewed-by: Yang Weijiang <weijiang.yang@intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Message-Id: <20230406064041.420039-1-yang.zhong@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Coverity complains (CID 1507880) that the declaration "int error_code;"
in mmu_translate() is unreachable code. Since this is only a declaration,
this isn't actually a bug, but:
* it's a bear-trap for future changes, because if it was changed to
include an initialization 'int error_code = foo;' then the
initialization wouldn't actually happen (being dead code)
* it's against our coding style, which wants declarations to be
at the start of blocks
* it means that anybody reading the code has to go and look up
exactly what the C rules are for skipping over variable declarations
using a goto
Move the declaration to the top of the function.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230406155946.3362077-1-peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This had been pulled in via qemu/plugin.h from hw/core/cpu.h,
but that will be removed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-5-richard.henderson@linaro.org>
[AJB: add various additional cases shown by CI]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-15-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
Upstream commit ddf0fd9ae1 "hw/xen: Support HVM_PARAM_CALLBACK_TYPE_GSI callback"
added kvm_xen_maybe_deassert_callback usage to target/i386/kvm/kvm.c file without
conditional preprocessing check. This breaks any build not using CONFIG_XEN_EMU.
Protect call by conditional preprocessing to allow build without CONFIG_XEN_EMU.
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20230308130557.2420-1-mrezanin@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
All uses are strictly read-only. Most of the obviously so,
as direct arguments to gen_helper_*.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230306175230.7110-9-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
- split user and softmmu code
- use cleaner headers for tb_flush, target_ulong
- probe for gdb multiarch support at configure
- make syscall handling target independent
- add update guest debug of accel ops
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Merge tag 'pull-gdbstub-070323-3' of https://gitlab.com/stsquad/qemu into staging
gdbstub refactor:
- split user and softmmu code
- use cleaner headers for tb_flush, target_ulong
- probe for gdb multiarch support at configure
- make syscall handling target independent
- add update guest debug of accel ops
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# gpg: Signature made Tue 07 Mar 2023 20:45:23 GMT
# gpg: using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8 DF35 FBD0 DB09 5A9E 2A44
* tag 'pull-gdbstub-070323-3' of https://gitlab.com/stsquad/qemu: (30 commits)
gdbstub: move update guest debug to accel ops
gdbstub: Build syscall.c once
stubs: split semihosting_get_target from system only stubs
gdbstub: Adjust gdb_do_syscall to only use uint32_t and uint64_t
gdbstub: Remove gdb_do_syscallv
gdbstub: split out softmmu/user specifics for syscall handling
include: split target_long definition from cpu-defs
testing: probe gdb for supported architectures ahead of time
gdbstub: only compile gdbstub twice for whole build
gdbstub: move syscall handling to new file
gdbstub: move register helpers into standalone include
gdbstub: don't use target_ulong while handling registers
gdbstub: fix address type of gdb_set_cpu_pc
gdbstub: specialise stub_can_reverse
gdbstub: introduce gdb_get_max_cpus
gdbstub: specialise target_memory_rw_debug
gdbstub: specialise handle_query_attached
gdbstub: abstract target specific details from gdb_put_packet_binary
gdbstub: rationalise signal mapping in softmmu
gdbstub: move chunks of user code into own files
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
These inline helpers are all used by target specific code so move them
out of the general header so we don't needlessly pollute the rest of
the API with target specific stuff.
Note we have to include cpu.h in semihosting as it was relying on a
side effect before.
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230302190846.2593720-21-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-21-richard.henderson@linaro.org>
This is only part of it; we will also need to get the PV back end drivers
to tear down their own mappings (or do it for them, but they kind of need
to stop using the pointers too).
Some more work on the actual PV back ends and xen-bus code is going to be
needed to really make soft reset and migration fully functional, and this
part is the basis for that.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Compute the eflags write mask separately, leaving one call
to the helper. Use tcg_constant_i32.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Translators are no longer required to free tcg temporaries.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since commit a0e61807a3 ("qapi: Remove QMP events and commands from
user-mode builds") we don't generate the "qapi-commands-machine.h"
header in a user-emulation-only build.
Guard qmp_query_cpu_definitions() within CONFIG_USER_ONLY; move
x86_cpu_class_check_missing_features() closer since it is only used
by this QMP command handler.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230223155540.30370-3-philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Since tcg_temp_new is now identical, use that.
In some cases we can avoid a copy from A0 or T0.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for returning the number of insns generated
via the same pointer. Adjust only the prototypes so far.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-23-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-11-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-8-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-3-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The default number of PIRQs is set to 256 to avoid issues with 32-bit MSI
devices. Allow it to be increased if the user desires.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
The way that Xen handles MSI PIRQs is kind of awful.
There is a special MSI message which targets a PIRQ. The vector in the
low bits of data must be zero. The low 8 bits of the PIRQ# are in the
destination ID field, the extended destination ID field is unused, and
instead the high bits of the PIRQ# are in the high 32 bits of the address.
Using the high bits of the address means that we can't intercept and
translate these messages in kvm_send_msi(), because they won't be caught
by the APIC — addresses like 0x1000fee46000 aren't in the APIC's range.
So we catch them in pci_msi_trigger() instead, and deliver the event
channel directly.
That isn't even the worst part. The worst part is that Xen snoops on
writes to devices' MSI vectors while they are *masked*. When a MSI
message is written which looks like it targets a PIRQ, it remembers
the device and vector for later.
When the guest makes a hypercall to bind that PIRQ# (snooped from a
marked MSI vector) to an event channel port, Xen *unmasks* that MSI
vector on the device. Xen guests using PIRQ delivery of MSI don't
ever actually unmask the MSI for themselves.
Now that this is working we can finally enable XENFEAT_hvm_pirqs and
let the guest use it all.
Tested with passthrough igb and emulated e1000e + AHCI.
CPU0 CPU1
0: 65 0 IO-APIC 2-edge timer
1: 0 14 xen-pirq 1-ioapic-edge i8042
4: 0 846 xen-pirq 4-ioapic-edge ttyS0
8: 1 0 xen-pirq 8-ioapic-edge rtc0
9: 0 0 xen-pirq 9-ioapic-level acpi
12: 257 0 xen-pirq 12-ioapic-edge i8042
24: 9600 0 xen-percpu -virq timer0
25: 2758 0 xen-percpu -ipi resched0
26: 0 0 xen-percpu -ipi callfunc0
27: 0 0 xen-percpu -virq debug0
28: 1526 0 xen-percpu -ipi callfuncsingle0
29: 0 0 xen-percpu -ipi spinlock0
30: 0 8608 xen-percpu -virq timer1
31: 0 874 xen-percpu -ipi resched1
32: 0 0 xen-percpu -ipi callfunc1
33: 0 0 xen-percpu -virq debug1
34: 0 1617 xen-percpu -ipi callfuncsingle1
35: 0 0 xen-percpu -ipi spinlock1
36: 8 0 xen-dyn -event xenbus
37: 0 6046 xen-pirq -msi ahci[0000:00:03.0]
38: 1 0 xen-pirq -msi-x ens4
39: 0 73 xen-pirq -msi-x ens4-rx-0
40: 14 0 xen-pirq -msi-x ens4-rx-1
41: 0 32 xen-pirq -msi-x ens4-tx-0
42: 47 0 xen-pirq -msi-x ens4-tx-1
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
This wires up the basic infrastructure but the actual interrupts aren't
there yet, so don't advertise it to the guest.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Just hook up the basic hypercalls to stubs in xen_evtchn.c for now.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Just the basic shell, with the event channel hookup. It only dumps the
buffer for now; a real ring implmentation will come in a subsequent patch.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Which is used to fetch xenstore PFN and port to be used
by the guest. This is preallocated by the toolstack when
guest will just read those and use it straight away.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Xen has eight frames at 0xfeff8000 for this; we only really need two for
now and KVM puts the identity map at 0xfeffc000, so limit ourselves to
four.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Introduce support for one shot and periodic mode of Xen PV timers,
whereby timer interrupts come through a special virq event channel
with deadlines being set through:
1) set_timer_op hypercall (only oneshot)
2) vcpu_op hypercall for {set,stop}_{singleshot,periodic}_timer
hypercalls
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
The guest is permitted to specify an arbitrary domain/bus/device/function
and INTX pin from which the callback IRQ shall appear to have come.
In QEMU we can only easily do this for devices that actually exist, and
even that requires us "knowing" that it's a PCMachine in order to find
the PCI root bus — although that's OK really because it's always true.
We also don't get to get notified of INTX routing changes, because we
can't do that as a passive observer; if we try to register a notifier
it will overwrite any existing notifier callback on the device.
But in practice, guests using PCI_INTX will only ever use pin A on the
Xen platform device, and won't swizzle the INTX routing after they set
it up. So this is just fine.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
The GSI callback (and later PCI_INTX) is a level triggered interrupt. It
is asserted when an event channel is delivered to vCPU0, and is supposed
to be cleared when the vcpu_info->evtchn_upcall_pending field for vCPU0
is cleared again.
Thankfully, Xen does *not* assert the GSI if the guest sets its own
evtchn_upcall_pending field; we only need to assert the GSI when we
have delivered an event for ourselves. So that's the easy part, kind of.
There's a slight complexity in that we need to hold the BQL before we
can call qemu_set_irq(), and we definitely can't do that while holding
our own port_lock (because we'll need to take that from the qemu-side
functions that the PV backend drivers will call). So if we end up
wanting to set the IRQ in a context where we *don't* already hold the
BQL, defer to a BH.
However, we *do* need to poll for the evtchn_upcall_pending flag being
cleared. In an ideal world we would poll that when the EOI happens on
the PIC/IOAPIC. That's how it works in the kernel with the VFIO eventfd
pairs — one is used to trigger the interrupt, and the other works in the
other direction to 'resample' on EOI, and trigger the first eventfd
again if the line is still active.
However, QEMU doesn't seem to do that. Even VFIO level interrupts seem
to be supported by temporarily unmapping the device's BARs from the
guest when an interrupt happens, then trapping *all* MMIO to the device
and sending the 'resample' event on *every* MMIO access until the IRQ
is cleared! Maybe in future we'll plumb the 'resample' concept through
QEMU's irq framework but for now we'll do what Xen itself does: just
check the flag on every vmexit if the upcall GSI is known to be
asserted.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Philippe Mathieu-Daudé