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>
A user-mode executable is never in real-mode. Since we're adding
an accessor macro, pull the value directly out of flags for sysemu.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-7-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-6-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-5-richard.henderson@linaro.org>
In vm86 mode, we use the same helper as real-mode, but with
an extra check for IOPL. All non-exceptional paths set EFLAGS.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-4-richard.henderson@linaro.org>
Split out the check for CPL != 0 and the raising of #GP.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-3-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210514151342.384376-2-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>
For now we just copy over the previous user stubs, but really,
everything that requires s->cpl == 0 should be impossible
to trigger from user-mode emulation.
Later on we should add a check that asserts this easily f.e.:
static bool check_cpl0(DisasContext *s)
{
int cpl = s->cpl;
#ifdef CONFIG_USER_ONLY
assert(cpl == 3);
#endif
if (cpl != 0) {
gen_exception(s, EXCP0D_GPF, s->pc_start - s->cs_base);
return false;
}
return true;
}
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-17-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
create a separate tcg/sysemu/fpu_helper.c for the sysemu-only parts.
For user mode, some small #ifdefs remain in tcg/fpu_helper.c
which do not seem worth splitting into their own user-mode module.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-16-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
for user-mode, assert that the hidden IOBPT flags are not set
while attempting to generate io_bpt helpers.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-14-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
smm is only really useful for sysemu, split in two modules
around the CONFIG_USER_ONLY, in order to remove the ifdef
and use the build system instead.
add cpu_abort() when detecting attempts to enter SMM mode via
SMI interrupt in user-mode, and assert that the cpu is not
in SMM mode while translating RSM instructions.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-12-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
overall, all devices' realize functions take an Error **errp, but return void.
hw/core/qdev.c code, which realizes devices, therefore does:
local_err = NULL;
dc->realize(dev, &local_err);
if (local_err != NULL) {
goto fail;
}
However, we can improve at least accel_cpu to return a meaningful bool value.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-9-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
i386 is the first user of AccelCPUClass, allowing to split
cpu.c into:
cpu.c cpuid and common x86 cpu functionality
host-cpu.c host x86 cpu functions and "host" cpu type
kvm/kvm-cpu.c KVM x86 AccelCPUClass
hvf/hvf-cpu.c HVF x86 AccelCPUClass
tcg/tcg-cpu.c TCG x86 AccelCPUClass
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[claudio]:
Rebased on commit b8184135 ("target/i386: allow modifying TCG phys-addr-bits")
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20210322132800.7470-5-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The helper_* functions must use GETPC() to unwind from TCG.
The cpu_x86_* functions cannot, and directly calling the
helper_* functions is a bug. Split out new functions that
perform the work and can be used by both.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Tested-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210322132800.7470-4-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Change the prefix from "helper" to "do". The former should be
reserved for those functions that are called from TCG; the latter
is in use within the file already for those functions that are
called from the helper functions, adding a "retaddr" argument.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Tested-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210322132800.7470-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These two opcodes only allow a memory operand.
Lacking the check for a register operand, we used the A0 temp
without initialization, which led to a tcg abort.
Buglink: https://bugs.launchpad.net/qemu/+bug/1921138
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210324164650.128608-1-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
env->error_code is only 32-bits wide, so the high 32 bits of EXITINFO1
are being lost. However, even though saving guest state and restoring
host state must be delayed to do_vmexit, because they might take tb_lock,
it is always possible to write to the VMCB. So do this for the exit
code and EXITINFO1, just like it is already being done for EXITINFO2.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use g2h_untagged in contexts that have no cpu, e.g. the binary
loaders that operate before the primary cpu is created. As a
colollary, target_mmap and friends must use untagged addresses,
since they are used by the loaders.
Use g2h_untagged on values returned from target_mmap, as the
kernel never applies a tag itself.
Use g2h_untagged on all pc values. The only current user of
tags, aarch64, removes tags from code addresses upon branch,
so "pc" is always untagged.
Use g2h with the cpu context on hand wherever possible.
Use g2h_untagged in lock_user, which will be updated soon.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210212184902.1251044-13-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Protection Keys for Supervisor-mode pages is a simple extension of
the PKU feature that QEMU already implements. For supervisor-mode
pages, protection key restrictions come from a new MSR. The MSR
has no XSAVE state associated to it.
PKS is only respected in long mode. However, in principle it is
possible to set the MSR even outside long mode, and in fact
even the XSAVE state for PKRU could be set outside long mode
using XRSTOR. So do not limit the migration subsections for
PKRU and PKRS to long mode.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch fixes a translation bug for a subset of x86 BMI instructions
such as the following:
c4 e2 f9 f7 c0 shlxq %rax, %rax, %rax
Currently, these incorrectly generate an undefined instruction exception
when SSE is disabled via CR4, while instructions like "shrxq" work fine.
The problem appears to be related to BMI instructions encoded using VEX
and with a mandatory prefix of "0x66" (data). Instructions with this
data prefix (such as shlxq) are currently rejected. Instructions with
other mandatory prefixes (such as shrxq) translate as expected.
This patch removes the incorrect check in "gen_sse" that causes the
exception to be generated. For the non-BMI cases, the check is
redundant: prefixes are already checked at line 3696.
Buglink: https://bugs.launchpad.net/qemu/+bug/1748296
Signed-off-by: David Greenaway <dgreenaway@google.com>
Message-Id: <20210114063958.1508050-1-dgreenaway@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
we cannot in principle make the TCG Operations field definitions
conditional on CONFIG_TCG in code that is included by both common_ss
and specific_ss modules.
Therefore, what we can do safely to restrict the TCG fields to TCG-only
builds, is to move all tcg cpu operations into a separate header file,
which is only included by TCG, target-specific code.
This leaves just a NULL pointer in the cpu.h for the non-TCG builds.
This also tidies up the code in all targets a bit, having all TCG cpu
operations neatly contained by a dedicated data struct.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20210204163931.7358-16-cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The TCG-specific CPU methods will be moved to a separate struct,
to make it easier to move accel-specific code outside generic CPU
code in the future. Start by moving tcg_initialize().
The new CPUClass.tcg_opts field may eventually become a pointer,
but keep it an embedded struct for now, to make code conversion
easier.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
[claudio: move TCGCpuOperations inside include/hw/core/cpu.h]
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210204163931.7358-2-cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use the dedicated X86Seg enum type for segment registers.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210109233427.749748-1-f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There is nothing within the translators that ought to be
changing the TranslationBlock data, so make it const.
This does not actually use the read-only copy of the
data structure that exists within the rx region.
Reviewed-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When the 'int N' instruction is executed in protected mode, the
pseudocode in the architecture manual specifies that we need to check:
* vector number within IDT limits
* selected IDT descriptor is a valid type (interrupt, trap or task gate)
* if this was a software interrupt then gate DPL < CPL
The way we had structured the code meant that the privilege check for
software interrupts ended up not in the code path taken for task gate
handling, because all of the task gate handling code was in the 'case 5'
of the switch which was checking "is this descriptor a valid type".
Move the task gate handling code out of that switch (so that it is now
purely doing the "valid type?" check) and below the software interrupt
privilege check.
The effect of this missing check was that in a guest userspace binary
executing 'int 8' would cause a guest kernel panic rather than the
userspace binary being handed a SEGV.
This is essentially the same bug fixed in VirtualBox in 2012:
https://www.halfdog.net/Security/2012/VirtualBoxSoftwareInterrupt0x8GuestCrash/
Note that for QEMU this is not a security issue because it is only
present when using TCG.
Fixes: https://bugs.launchpad.net/qemu/+bug/1813201
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20201121224445.16236-1-peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
The current "#ifdef TARGET_X86_64" statement affects
the compiler's determination of fall through.
When using -Wimplicit-fallthrough in our CFLAGS, the compiler showed warning:
target/i386/translate.c: In function ‘gen_shiftd_rm_T1’:
target/i386/translate.c:1773:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (is_right) {
^
target/i386/translate.c:1782:5: note: here
case MO_32:
^~~~
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201211152426.350966-6-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
make it a regular function.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201212155530.23098-9-cfontana@suse.de>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
to do this, we need to take code out of cpu.c and helper.c,
and also move some prototypes from cpu.h, for code that is
needed in tcg/xxx_helper.c, and which in turn is part of the
callbacks registered by the class initialization.
Therefore, do some shuffling of the parts of cpu.h that
are only relevant for tcg/, and put them in tcg/helper-tcg.h
For FT0 and similar macros, put them in tcg/fpu-helper.c
since they are used only there.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201212155530.23098-8-cfontana@suse.de>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
