Split out a function to adjust the raw signal pc into a
value that could be passed to cpu_restore_state.
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
v2: Adjust pc in place; return MMUAccessType.
Currently the change in cpu_tb_exec is masked by the debug exception
being raised by the translators. But this allows us to remove that code.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add cpu_ld/st_mmu memory primitives.
Move helper_ld/st memory helpers out of tcg.h.
Canonicalize alignment flags in MemOp.
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Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20211013' into staging
Use MO_128 for 16-byte atomic memory operations.
Add cpu_ld/st_mmu memory primitives.
Move helper_ld/st memory helpers out of tcg.h.
Canonicalize alignment flags in MemOp.
# gpg: Signature made Wed 13 Oct 2021 10:48:45 AM PDT
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg: issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [ultimate]
* remotes/rth/tags/pull-tcg-20211013:
tcg: Canonicalize alignment flags in MemOp
tcg: Move helper_*_mmu decls to tcg/tcg-ldst.h
target/arm: Use cpu_*_mmu instead of helper_*_mmu
target/sparc: Use cpu_*_mmu instead of helper_*_mmu
target/s390x: Use cpu_*_mmu instead of helper_*_mmu
target/mips: Use 8-byte memory ops for msa load/store
target/mips: Use cpu_*_data_ra for msa load/store
accel/tcg: Move cpu_atomic decls to exec/cpu_ldst.h
accel/tcg: Add cpu_{ld,st}*_mmu interfaces
target/hexagon: Implement cpu_mmu_index
target/s390x: Use MO_128 for 16 byte atomics
target/ppc: Use MO_128 for 16 byte atomics
target/i386: Use MO_128 for 16 byte atomics
target/arm: Use MO_128 for 16 byte atomics
memory: Log access direction for invalid accesses
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These functions have been replaced by cpu_*_mmu as the
most proper interface to use from target code.
Hide these declarations from code that should not use them.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These functions are much closer to the softmmu helper
functions, in that they take the complete MemOpIdx,
and from that they may enforce required alignment.
The previous cpu_ldst.h functions did not have alignment info,
and so did not enforce it. Retain this by adding MO_UNALN to
the MemOp that we create in calling the new functions.
Note that we are not yet enforcing alignment for user-only,
but we now have the information with which to do so.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We can handle up to a static amount of memory slots, capped by the size of
an internal array.
Let's make sure that array size is the only source of truth for the number
of elements in that array.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211008054616.43828-1-agraf@csgraf.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SEV is x86-specific, no need to add its stub to other
architectures. Move the stub file to target/i386/kvm/.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211007161716.453984-5-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Coverity doesn't know enough about how we have arranged our plugin TCG
ops to know we will always have incremented insn_idx before injecting
the callback. Let us assert it for the benefit of Coverity and protect
ourselves from accidentally breaking the assumption and triggering
harder to grok errors deeper in the code if we attempt a negative
indexed array lookup.
However to get to this point we re-factor the code and remove the
second hand instruction boundary detection in favour of scanning the
full set of ops and using the existing INDEX_op_insn_start to cleanly
detect when the instruction has started. As we no longer need the
plugin specific list of ops we delete that.
My initial benchmarks shows no discernible impact of dropping the
plugin specific ops list.
Fixes: Coverity 1459509
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210917162332.3511179-12-alex.bennee@linaro.org>
There is no point in encoding load/store within a bit of
the memory trace info operand. Represent atomic operations
as a single read-modify-write tracepoint. Use MemOpIdx
instead of inventing a form specifically for traces.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use the MemOpIdx directly, rather than the rearrangement
of the same bits currently done by the trace infrastructure.
Pass in enum qemu_plugin_mem_rw so that we are able to treat
read-modify-write operations as a single operation.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We will shortly use the MemOpIdx directly, but in the meantime
re-compute the trace meminfo.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We (will) often have the complete MemOpIdx handy, so use that.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We're about to move this out of tcg.h, so rename it
as we did when moving MemOp.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We are already inconsistent about whether or not
MO_SIGN is set in trace_mem_get_info. Dropping it
entirely allows some simplification.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Provide a name field for all the memory listeners. It can be used to identify
which memory listener is which.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210817013553.30584-2-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 372579427a ("tcg: enable thread-per-vCPU") added the following
comment describing EXCP_HALTED in qemu_tcg_cpu_thread_fn():
case EXCP_HALTED:
/* during start-up the vCPU is reset and the thread is
* kicked several times. If we don't ensure we go back
* to sleep in the halted state we won't cleanly
* start-up when the vCPU is enabled.
*
* cpu->halted should ensure we sleep in wait_io_event
*/
g_assert(cpu->halted);
break;
qemu_wait_io_event() is sysemu-specific, so we can restrict the
cpu_handle_halt() call in cpu_exec() to system emulation.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210912172731.789788-2-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Sleep on WFI until the VTIMER is due but allow ourselves to be woken
up on IPI.
In this implementation IPI is blocked on the CPU thread at startup and
pselect() is used to atomically unblock the signal and begin sleeping.
The signal is sent unconditionally so there's no need to worry about
races between actually sleeping and the "we think we're sleeping"
state. It may lead to an extra wakeup but that's better than missing
it entirely.
Signed-off-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Acked-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210916155404.86958-6-agraf@csgraf.de
[agraf: Remove unused 'set' variable, always advance PC on WFX trap,
support vm stop / continue operations and cntv offsets]
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Acked-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
With Apple Silicon available to the masses, it's a good time to add support
for driving its virtualization extensions from QEMU.
This patch adds all necessary architecture specific code to get basic VMs
working, including save/restore.
Known limitations:
- WFI handling is missing (follows in later patch)
- No watchpoint/breakpoint support
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210916155404.86958-5-agraf@csgraf.de
[PMM: added missing #include]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We will need to install a migration helper for the ARM hvf backend.
Let's introduce an arch callback for the overall hvf init chain to
do so.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210916155404.86958-4-agraf@csgraf.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Hvf's permission bitmap during and after dirty logging does not include
the HV_MEMORY_EXEC permission. At least on Apple Silicon, this leads to
instruction faults once dirty logging was enabled.
Add the bit to make it work properly.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210916155404.86958-3-agraf@csgraf.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
x86_64 dotnet/runtime uses cmpxchg for code patching. When running it
under s390x qemu-linux user, cpu_signal_handler() does not recognize
this as a write and does not restore PAGE_WRITE cleared by
tb_page_add(), incorrectly forwarding the signal to the guest code.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210803221606.150103-1-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All targets call TCGCPUOps::cpu_exec_interrupt() from sysemu code.
Move its declaration to restrict it to system emulation.
Extend the code guarded.
Restrict the static inlined need_replay_interrupt() method to
avoid a "defined but not used" warning.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210911165434.531552-24-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
do_interrupt() is sysemu specific. However due to some X86
specific hack, it is also used in user-mode emulation, which
is why it couldn't be restricted to CONFIG_SOFTMMU (see the
comment around added in commit 7827168471: "cpu: tcg_ops:
move to tcg-cpu-ops.h, keep a pointer in CPUClass").
Keep the hack but rename the handler as fake_user_interrupt()
and restrict do_interrupt() to sysemu.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210911165434.531552-6-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The TCG_KICK_PERIOD macro is already defined in tcg-accel-ops-rr.h.
Remove it from tcg-accel-ops-rr.c.
Signed-off-by: Luc Michel <lmichel@kalray.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210811141229.12470-1-lmichel@kalray.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
translate_insn() implementations fetch instruction bytes piecemeal,
which can cause qemu-user to generate inconsistent translations if
another thread modifies them concurrently [1].
Fix by making pages containing translated instruction non-writable
right before loading instruction bytes from them.
[1] https://lists.nongnu.org/archive/html/qemu-devel/2021-08/msg00644.html
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20210805204835.158918-1-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This crept in as either a cut-and-paste error, or rebase error.
Fixes: cfec388518 ("atomic_template: add inline trace/plugin helpers")
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210729004647.282017-24-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
PowerPC has two KVM types (HV, PR) that translate into three kernel
modules:
kvm.ko - common kvm code
kvm_hv.ko - kvm running with MSR_HV=1 or MSR_HV|PR=0 in a nested guest.
kvm_pr.ko - kvm running in usermode MSR_PR=1.
Since the two KVM types can both be running at the same time, this
creates a situation in which it is possible for one or both of the
modules to fail to initialize, leaving the generic one behind. This
leads QEMU to think it can create a guest, but KVM will fail when
calling the type-specific code:
ioctl(KVM_CREATE_VM) failed: 22 Invalid argument
qemu-kvm: failed to initialize KVM: Invalid argument
Ideally this would be solved kernel-side, but it might be a while
until we can get rid of one of the modules. So in the meantime this
patch tries to make this less confusing for the end user by adding a
more elucidative message:
ioctl(KVM_CREATE_VM) failed: 22 Invalid argument
PPC KVM module is not loaded. Try 'modprobe kvm_hv'.
[dwg: Fixed error in #elif which failed compile on !ppc hosts]
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20210722141340.2367905-1-farosas@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
From clang-13:
accel/tcg/cpu-exec.c:783:15: error: variable 'cc' set but not used \
[-Werror,-Wunused-but-set-variable]
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In cpu_loop_exec_tb(), we decide whether to look for a TB with
exactly insns_left instructions in it using the condition
(!cpu->icount_extra && insns_left > 0 && insns_left < tb->icount)
The check for icount_extra == 0 is unnecessary, because we just set
insns_left = MIN(0xffff, cpu->icount_budget);
icount_extra = icount_budget - insns_left;
and so icount_extra can only be non-zero if icount_budget > 0xffff
and insns_left == 0xffff. But in that case insns_left >= tb->icount
because 0xffff is much larger than TCG_MAX_INSNS, so the condition
will be false anyway.
Remove the unnecessary check, and instead assert:
* that we are only going to execute a partial TB here if the
icount budget has run out (ie icount_extra == 0)
* that the number of insns we're going to execute does fit into
the CF_COUNT_MASK
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210725174405.24568-3-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In cpu_loop_exec_tb() we were bounding the number of insns we might
try to execute in a TB using CF_COUNT_MASK. This is incorrect,
because we can validly put up to 0xffff into icount_decr.u16.low. In
particular, since commit 78ff82bb1b reduced CF_COUNT_MASK to
511 this meant that we would incorrectly only try to execute 511
instructions in a 512-instruction TB, which could result in QEMU
hanging when in icount mode.
Use the actual maximum value, which is 0xffff. (This brings this code
in to line with the similar logic in icount_prepare_for_run() in
tcg-accel-ops-icount.c.)
Fixes: 78ff82bb1b
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/499
Message-Id: <20210725174405.24568-2-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Set CF_SINGLE_STEP when single-stepping is enabled.
This avoids the need to flush all tb's when turning
single-stepping on or off.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The access internal to tb_cflags() is atomic.
Avoid re-reading it as such for the multiple uses.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Trigger breakpoints before beginning translation of a TB
that would begin with a BP. Thus we never generate code
for the BP at all.
Single-step instructions within a page containing a BP so
that we are sure to check each insn for the BP as above.
We no longer need to flush any TBs when changing BPs.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/286
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/404
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/489
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We are going to want two things:
(1) check for breakpoints will want to break out of the loop here,
(2) cflags can only be calculated with pc in hand.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Request that the one TB returns immediately, so that
we release the exclusive lock as soon as possible.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210717221851.2124573-7-richard.henderson@linaro.org>
Exchange the test in translator_use_goto_tb for CF_NO_GOTO_TB,
and the test in tb_gen_code for setting CF_COUNT_MASK to 1.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210717221851.2124573-6-richard.henderson@linaro.org>
The purpose of suppressing goto_ptr from -d nochain had been
to return to the main loop so that -d cpu would be recognized.
But we now include -d cpu logging in helper_lookup_tb_ptr so
there is no need to exclude goto_ptr.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210717221851.2124573-5-richard.henderson@linaro.org>
Move the -d nochain check to bits on tb->cflags.
These will be used for more than -d nochain shortly.
Set bits during curr_cflags, test them in translator_use_goto_tb,
assert we're not doing anything odd in tcg_gen_goto_tb. The test
in tcg_gen_exit_tb is redundant with the assert for goto_tb_issue_mask.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210717221851.2124573-4-richard.henderson@linaro.org>
We will shortly have more than a simple member read here,
with stuff not necessarily exposed to exec/exec-all.h.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210717221851.2124573-3-richard.henderson@linaro.org>
The space reserved for CF_COUNT_MASK was overly large.
Reduce to free up cflags bits and eliminate an extra test.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210717221851.2124573-2-richard.henderson@linaro.org>
Use trace_mem_get_info instead of trace_mem_build_info,
using the TCGMemOpIdx that we already have. Do this in
the atomic_trace_*_pre function as common subroutines.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Unify the parameters of atomic_mmu_lookup between cputlb.c and
user-exec.c. Call the function directly, and remove the macros.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All definitions are now empty.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All instances of EXTRA_ARGS are now identical.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reduce the amount of code duplication by always passing
the TCGMemOpIdx argument to helper_atomic_*. This is not
currently used for user-only, but it's easy to ignore.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Always provide the atomic interface using TCGMemOpIdx oi
and uintptr_t retaddr. Rename from helper_* to cpu_* so
as to (mostly) match the exec/cpu_ldst.h functions, and
to emphasize that they are not callable from TCG directly.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use it to avoid some clang-12 -Watomic-alignment errors,
forcing some structures to be aligned and as a pointer when
we have ensured that the address is aligned.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The compiler rightly complains when we build on 32 bit that casting
uint64_t into a void is a bad idea. We are really dealing with a host
pointer at this point so treat it as such. This does involve
a uintptr_t cast of the result of the TLB addend as we know that has
to point to the host memory.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210709143005.1554-28-alex.bennee@linaro.org>
Split out CPU_LOG_EXEC and CPU_LOG_TB_CPU logging from
cpu_tb_exec to a new function. Perform only one pc
range check after a combined mask check.
Use the new function in lookup_tb_ptr. This enables
CPU_LOG_TB_CPU between indirectly chained tbs.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Now that we've moved helper_lookup_tb_ptr, the only user
of tb-lookup.h is cpu-exec.c; merge the contents in.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This will allow additional code sharing.
No functional change.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add a generic version of the common use_goto_tb test.
Various targets avoid the page crossing test for CONFIG_USER_ONLY,
but that is wrong: mmap and mprotect can change page permissions.
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We can call do_tb_phys_invalidate from an iocontext, which has
no per-thread tcg_ctx. Move this to tb_ctx, which is global.
The actual update still takes place with a lock held, so only
an atomic set is required, not an atomic increment.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/457
Tested-by: Viktor Ashirov <vashirov@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The function is called only at tcg_gen_code() when duplicated TBs
are translated by different threads, and when the tcg_region_tree
is reset. Bake it into the underlying GTree as its value destroy
function to unite these situations.
Also remove tcg_region_tree_traverse() which now becomes useless.
Signed-off-by: Liren Wei <lrwei@bupt.edu.cn>
Message-Id: <8dc352f08d038c4e7a1f5f56962398cdc700c3aa.1625404483.git.lrwei@bupt.edu.cn>
[rth: Name the new tb_tc_cmp parameter correctly.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
TranslationBlocks not inserted into the corresponding region
tree shall be regarded as partially initialized objects, and
needs to be finalized first before inserting into QHT.
Signed-off-by: Liren Wei <lrwei@bupt.edu.cn>
Message-Id: <f9fc263f71e11b6308d8c1fbc0dd366bf4aeb532.1625404483.git.lrwei@bupt.edu.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
One more little step towards modular tcg ...
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-35-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Build tcg accel ops as module.
Which is only a small fraction of tcg.
Also only x86 for now.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-30-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add module annotations for tcg so autoloading works.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-29-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Allow building accelerators as module.
Start with qtest as first user.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-28-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add module annotations for qtest so autoloading works.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-27-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Call module_object_class_by_name() instead of object_class_by_name()
for objects possibly implemented as module
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-26-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The trap number for a page fault on BSD systems is T_PAGEFLT
not 0xe -- 0xe is used by Linux and represents the intel hardware
trap vector. The BSD kernels, however, translate this to T_PAGEFLT
in their Xpage, Xtrap0e, Xtrap14, etc fault handlers. This is true
for i386 and x86_64, though the name of the trap hanlder can very
on the flavor of BSD. As far as I can tell, Linux doesn't provide
a define for this value. Invent a new one (PAGE_FAULT_TRAP) and
use it instead to avoid uglier ifdefs.
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Signed-off-by: Juergen Lock <nox@FreeBSD.org>
[ Rework to avoid ifdefs and expand it to i386 ]
Signed-off-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20210625045707.84534-3-imp@bsdimp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Found this when I wanted to try the per-vcpu dirty rate series out, then I
found that it's not really working and it can quickly hang death a guest. I
found strange errors (e.g. guest crash after migration) happens even without
the per-vcpu dirty rate series.
When merging dirty ring, probably no one notice that the trivial renaming diff
[1] missed two existing references of kvm_dirty_ring_sizes; they do matter
since otherwise we'll mmap() a shorter range of memory after the renaming.
I think it didn't SIGBUS for me easily simply because some other stuff within
qemu mmap()ed right after the dirty rings (e.g. when testing 4096 slots, it
aligned with one small page on x86), so when we access the rings we've been
reading/writting to random memory elsewhere of qemu.
Fix the two sizes when map/unmap the shared dirty gfn memory.
[1] https://lore.kernel.org/qemu-devel/dac5f0c6-1bca-3daf-e5d2-6451dbbaca93@redhat.com/
Cc: Hyman Huang <huangy81@chinatelecom.cn>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210609014355.217110-1-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We had a single ATOMIC_MMU_LOOKUP macro that probed for
read+write on all atomic ops. This is incorrect for
plain atomic load and atomic store.
For user-only, we rely on the host page permissions.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/390
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As noted by qemu-plugins.h, plugins can neither read nor write
guest registers.
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As noted by qemu-plugins.h, enum qemu_plugin_cb_flags is
currently unused -- plugins can neither read nor write
guest registers.
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Let the compiler decide on inlining.
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These variables belong to the jit side, not the user side.
Since tcg_init_ctx is no longer used outside of tcg/, move
the declaration to tcg-internal.h.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Suggested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Start removing the include of hw/boards.h from tcg/.
Pass down the max_cpus value from tcg_init_machine,
where we have the MachineState already.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
There is only one caller, and shortly we will need access
to the MachineState, which tcg_init_machine already has.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Perform both tcg_context_init and tcg_region_init.
Do not leave this split to the caller.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We shortly want to use tcg_init for something else.
Since the hook is called init_machine, match that.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Buffer management is integral to tcg. Do not leave the allocation
to code outside of tcg/. This is code movement, with further
cleanups to follow.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
It consists of one function call and has only one caller.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Instead of delaying tcg_region_init until after tcg_prologue_init
is complete, do tcg_region_init first and let tcg_prologue_init
shrink the first region by the size of the generated prologue.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The hooks we have that call us after reset, init and loadvm really all
just want to say "The reference of all register state is in the QEMU
vcpu struct, please push it".
We already have a working pushing mechanism though called cpu->vcpu_dirty,
so we can just reuse that for all of the above, syncing state properly the
next time we actually execute a vCPU.
This fixes PSCI resets on ARM, as they modify CPU state even after the
post init call has completed, but before we execute the vCPU again.
To also make the scheme work for x86, we have to make sure we don't
move stale eflags into our env when the vcpu state is dirty.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Tested-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-13-agraf@csgraf.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We will need more than a single field for hvf going forward. To keep
the global vcpu struct uncluttered, let's allocate a special hvf vcpu
struct, similar to how hax does it.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Tested-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-12-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We can move the definition of hvf_vcpu_exec() into our internal
hvf header, obsoleting the need for hvf-accel-ops.h.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-11-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The hvf accel synchronize functions are only used as input for local
callback functions, so we can make them static.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-10-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
There is no reason to call the hvf specific hvf_cpu_synchronize_state()
when we can just use the generic cpu_synchronize_state() instead. This
allows us to have less dependency on internal function definitions and
allows us to make hvf_cpu_synchronize_state() static.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-9-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch splits the vcpu init and destroy functions into a generic and
an architecture specific portion. This also allows us to move the generic
functions into the generic hvf code, removing exported functions.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-8-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The ARM version of Hypervisor.framework no longer defines these two
types, so let's just revert to standard ones.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-7-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The hvf_set_phys_mem() function is only called within the same file.
Make it static.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-6-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch moves CPU and memory operations over. While at it, make sure
the code is consumable on non-i386 systems.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-4-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch moves the vCPU thread loop over.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-3-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch moves assert_hvf_ok() and introduces generic build infrastructure.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-2-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.
We still have several references to the old file, so let's fix them
with the following command:
sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Only the TCG accelerator uses the TranslationBlock API.
Move the tb-context.h / tb-hash.h / tb-lookup.h from the
global namespace to the TCG one (in accel/tcg).
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210524170453.3791436-3-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Only 2 headers require "exec/tb-context.h". Instead of having
all files including "exec/exec-all.h" also including it, directly
include it where it is required:
- accel/tcg/cpu-exec.c
- accel/tcg/translate-all.c
For plugins/plugin.h, we were implicitly relying on
exec/exec-all.h -> exec/tb-context.h -> qemu/qht.h
which is now included directly.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210524170453.3791436-2-f4bug@amsat.org>
[rth: Fix plugins/plugin.h compilation]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
KVM dirty ring is a new interface to pass over dirty bits from kernel to the
userspace. Instead of using a bitmap for each memory region, the dirty ring
contains an array of dirtied GPAs to fetch (in the form of offset in slots).
For each vcpu there will be one dirty ring that binds to it.
kvm_dirty_ring_reap() is the major function to collect dirty rings. It can be
called either by a standalone reaper thread that runs in the background,
collecting dirty pages for the whole VM. It can also be called directly by any
thread that has BQL taken.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-11-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is for KVM_CLEAR_DIRTY_LOG, which is only
useful for KVM_GET_DIRTY_LOG. Skip enabling it for kvm dirty ring.
More importantly, KVM_DIRTY_LOG_INITIALLY_SET will not wr-protect all the pages
initially, which is against how kvm dirty ring is used - there's no way for kvm
dirty ring to re-protect a page before it's notified as being written first
with a GFN entry in the ring! So when KVM_DIRTY_LOG_INITIALLY_SET is enabled
with dirty ring, we'll see silent data loss after migration.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-10-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a parameter for dirty gfn count for dirty rings. If zero, dirty ring is
disabled. Otherwise dirty ring will be enabled with the per-vcpu gfn count as
specified. If dirty ring cannot be enabled due to unsupported kernel or
illegal parameter, it'll fallback to dirty logging.
By default, dirty ring is not enabled (dirty-gfn-count default to 0).
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-9-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cache it too because we'll reference it more frequently in the future.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-8-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_physical_sync_dirty_bitmap() on the whole section is inaccurate, because
the section can be a superset of the memslot that we're working on. The result
is that if the section covers multiple kvm memslots, we could be doing the
synchronization for multiple times for each kvmslot in the section.
With the two helpers that we just introduced, it's very easy to do it right now
by calling the helpers.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-7-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
