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>
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 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>
Unify the duplicate code between get_hphys and mmu_translate, by simply
making get_hphys call mmu_translate. This also fixes the support for
5-level nested page tables.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In order to unify the two stages of page table lookup, we need
mmu_translate to use either the host CR0/EFER/CR4 or the guest's.
To do so, make mmu_translate use the same pg_mode constants that
were used for the NPT lookup.
This also prepares for adding 5-level NPT support, which however does
not work yet.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Extract the page table lookup out of handle_mmu_fault, which only has
to invoke mmu_translate and either fill the TLB or deliver the page
fault.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We will reuse the page walker for both SVM and regular accesses. To do
so we will build a function that receives the currently active paging
mode; start by including in cpu.h the constants and the function to go
from cr4/hflags/efer to the paging mode.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
while on x86 all CPU classes can use the same set of TCGCPUOps,
on ARM the right accel behavior depends on the type of the CPU.
So we need a way to specialize the accel behavior according to
the CPU. Therefore, add a second initialization, after the
accel_cpu->cpu_class_init, that allows to do this.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210322132800.7470-24-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
a number of registers are read as 64bit under the condition that
(hflags & HF_CS64_MASK) || TARGET_X86_64)
and a number of registers are written as 64bit under the condition that
(hflags & HF_CS64_MASK).
Provide some auxiliary functions that do that.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-20-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
