tb_gen_code() assumes that tb->size must never be zero, otherwise it
may produce spurious exceptions. For x86_64 this may happen when
creating a translation block for the vsyscall page.
Fix by pretending that vsyscall translation blocks have at least one
instruction.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210519045738.1335210-2-iii@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
tb_gen_code() assumes that tb->size must never be zero, otherwise it
may produce spurious exceptions. For xtensa this may happen when
decoding an unknown instruction, when handling a write into the
CCOUNT or CCOMPARE special register and when single-stepping the first
instruction of an exception handler.
Fix by pretending that the size of the respective translation block is
1 in all these cases.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Message-Id: <20210416154939.32404-4-iii@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
tb_gen_code() assumes that tb->size must never be zero, otherwise it
may produce spurious exceptions. For ARM this may happen when creating
a translation block for the commpage.
Fix by pretending that commpage translation blocks have at least one
instruction.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210416154939.32404-3-iii@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Hitting an uretprobe in a s390x TCG guest causes a SIGSEGV. What
happens is:
* uretprobe maps a userspace page containing an invalid instruction.
* uretprobe replaces the target function's return address with the
address of that page.
* When tb_gen_code() is called on that page, tb->size ends up being 0
(because the page starts with the invalid instruction), which causes
virt_page2 to point to the previous page.
* The previous page is not mapped, so this causes a spurious
translation exception.
tb->size must never be 0: even if there is an illegal instruction, the
instruction bytes that have been looked at must count towards tb->size.
So adjust s390x's translate_one() to act this way for both illegal
instructions and instructions that are known to generate exceptions.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210416154939.32404-2-iii@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
With the previous patch for check_io, we now have enough for
the compiler to dead-code eliminate all of the i/o helpers.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-51-richard.henderson@linaro.org>
The we never allow i/o from user-only, and the tss check
that helper_check_io does will always fail. Use an ifdef
within gen_check_io and return false, indicating that an
exception is known to be raised.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-50-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Drop helper_check_io[bwl] and expose their common
subroutine to tcg directly.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210514151342.384376-49-richard.henderson@linaro.org>
Pass in a pre-truncated TCGv_i32 value. We were doing the
truncation of EDX in multiple places, now only once per insn.
While all callers use s->tmp2_i32, for cleanliness of the
subroutine, use a parameter anyway.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-48-richard.henderson@linaro.org>
Get cur_eip from DisasContext. Do not require the caller
to use svm_is_rep; get prefix from DisasContext. Use the
proper symbolic constants for SVM_IOIO_*.
While we're touching all call sites, return bool in
preparation for gen_check_io raising #GP.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-47-richard.henderson@linaro.org>
At minimum, wrmsr can change efer, which affects HF_LMA.
Cc: qemu-stable@nongnu.org
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-46-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-45-richard.henderson@linaro.org>
The user-version is a no-op. This lets us completely
remove tcg/user/svm_stubs.c.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-44-richard.henderson@linaro.org>
Use a single helper, flush_page, to do the work.
Use gen_svm_check_intercept.
Perform the zero-extension for invlpga inline.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-43-richard.henderson@linaro.org>
These instructions are all privileged.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-42-richard.henderson@linaro.org>
Having the callers upcast to X86CPU is a waste, since we
don't need it. We even have to recover env in do_hlt.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-41-richard.henderson@linaro.org>
Pull the svm intercept check into the translator.
Pull the entire implementation of lmsw into the translator.
Push the check for CR8LEG into the regno validation switch.
Unify the gen_io_start check between read/write.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210514151342.384376-40-richard.henderson@linaro.org>
This function is only called from tcg/sysemu/.
There is no need for a stub in tcg/user/.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-39-richard.henderson@linaro.org>
When exiting helper_svm_check_intercept via exception, cpu_vmexit
calls cpu_restore_state, which will recover eip and cc_op via unwind.
Therefore we do not need to store eip or cc_op before the call.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-38-richard.henderson@linaro.org>
The param argument to helper_svm_check_intercept_param is always 0;
eliminate it and rename to helper_svm_check_intercept. Fold
gen_svm_check_intercept_param into gen_svm_check_intercept.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-37-richard.henderson@linaro.org>
Both invocations pass the start of the current instruction,
which is available as s->base.pc_next. The function sets
is_jmp, so we can eliminate a second setting.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-36-richard.henderson@linaro.org>
Any helper that always raises an exception or interrupt,
or simply exits to the main loop, can be so marked.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-35-richard.henderson@linaro.org>
Use STUB_HELPER to ensure that such calls are always eliminated.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-34-richard.henderson@linaro.org>
Our sysemu implementation is a stub. We can already intercept
instructions for vmexit, and raising #UD is trivial.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-33-richard.henderson@linaro.org>
For user-only, we do not need to check for VMM intercept.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-32-richard.henderson@linaro.org>
Most of the VMM instructions are already disabled for user-only,
by being usable only from ring 0.
The spec is intentionally loose for VMMCALL, allowing the VMM to
define syscalls for user-only. However, we're not emulating any
VMM, so VMMCALL can just raise #UD unconditionally.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210514151342.384376-31-richard.henderson@linaro.org>
This removes an ifdef from the middle of disas_insn,
and ensures that the branch is not reachable.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-30-richard.henderson@linaro.org>
Sort all of the single-byte members to the same area
of the structure, eliminating 8 bytes of padding.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-29-richard.henderson@linaro.org>
After fixing a typo in the comment, fixup for CODING_STYLE.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210514151342.384376-28-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-27-richard.henderson@linaro.org>
It's just as easy to clear the flag with AND than assignment.
In two cases the test for the bit can be folded together with
the test for HF_INHIBIT_IRQ_MASK.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-26-richard.henderson@linaro.org>
Both of these fields store the size of a single memory access,
so the range of values is 0-8.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-25-richard.henderson@linaro.org>
Currently, vex_l is either {0,1}; if in the future we implement
AVX-512, the max value will be 2. In vex_v we store a register
number. This is 0-15 for SSE, and 0-31 for AVX-512.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-24-richard.henderson@linaro.org>
The highest bit in this set is 0x40 (PREFIX_REX).
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-23-richard.henderson@linaro.org>
The range of values is -1 (none) to 5 (R_GS).
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-22-richard.henderson@linaro.org>
The value comes from tb->flags, which is uint32_t.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-21-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-20-richard.henderson@linaro.org>
Treat this flag exactly like we treat the other rex bits.
The -1 initialization is unused; the two tests are > 0 and == 1,
so the value can be reduced to a bool.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-19-richard.henderson@linaro.org>
Treat this flag exactly like we treat rex_b and rex_x.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-18-richard.henderson@linaro.org>
Change the storage from int to uint8_t since the value is in {0,8}.
For x86_64 add 0 in the macros to (1) promote the type back to int,
and (2) make the macro an rvalue.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-17-richard.henderson@linaro.org>
The existing flag, x86_64_hregs, does not accurately describe
its setting. It is true if and only if a REX prefix has been
seen. Yes, that affects the "h" regs, but that's secondary.
Add PREFIX_REX and include this bit in s->prefix. Add REX_PREFIX
so that the check folds away when x86_64 is compiled out.
Fold away the reg >= 8 check, because bit 3 of the register
number comes from the REX prefix in the first place.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-16-richard.henderson@linaro.org>
LMA disables traditional segmentation, exposing a flat address space.
This means that ADDSEG is off.
Since we're adding an accessor macro, pull the value directly out
of flags otherwise.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-15-richard.henderson@linaro.org>
LMA is a pre-requisite for CODE64, so there is no way to disable it
for x86_64-linux-user, and there is no way to enable it for i386.
Since we're adding an accessor macro, pull the value directly out
of flags when we're not assuming a constant.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-14-richard.henderson@linaro.org>
For x86_64 user-only, there is no way to leave 64-bit mode.
Without x86_64, there is no way to enter 64-bit mode. There is
an existing macro to aid with that; simply place it in the right
place in the ifdef chain.
Since we're adding an accessor macro, pull the value directly out
of flags when we're not assuming a constant.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-13-richard.henderson@linaro.org>
For user-only, SS32 == !VM86, because we are never in
real-mode. Since we cannot enter vm86 mode for x86_64
user-only, SS32 is always set.
Since we're adding an accessor macro, pull the value
directly out of flags otherwise.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-12-richard.henderson@linaro.org>
For user-only, CODE32 == !VM86, because we are never in real-mode.
Since we cannot enter vm86 mode for x86_64 user-only, CODE32 is
always set.
Since we're adding an accessor macro, pull the value directly out
of flags otherwise.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-11-richard.henderson@linaro.org>
For i386-linux-user, we can enter vm86 mode via the vm86(2) syscall.
That syscall explicitly returns to 32-bit mode, and the syscall does
not exist for a 64-bit x86_64 executable.
Since we're adding an accessor macro, pull the value directly out of
flags otherwise.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-10-richard.henderson@linaro.org>
On real hardware, the linux kernel has the iopl(2) syscall which
can set IOPL to 3, to allow e.g. the xserver to briefly disable
interrupts while programming the graphics card.
However, QEMU cannot and does not implement this syscall, so the
IOPL is never changed from 0. Which means that all of the checks
vs CPL <= IOPL are false for user-only.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-9-richard.henderson@linaro.org>
A user-mode executable always runs in ring 3.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-8-richard.henderson@linaro.org>
Peter Maydell
Ilya Leoshkevich
Richard Henderson