The memory writes done to push registers on the stack
on exception entry in M profile CPUs are supposed to
go via MPU permissions checks, which may cause us to
take a derived exception instead of the original one of
the MPU lookup fails. We were implementing these as
always-succeeds direct writes to physical memory.
Rewrite v7m_push_stack() to do the necessary checks.
Backports commit fd592d890ec40e3686760de84044230a8ebb1eb3 from qemu
In the v8M architecture, if the process of taking an exception
results in a further exception this is called a derived exception
(for example, an MPU exception when writing the exception frame to
memory). If the derived exception happens while pushing the initial
stack frame, we must ignore any subsequent possible exception
pushing the callee-saves registers.
In preparation for making the stack writes check for exceptions,
add a return value from v7m_push_stack() and a new parameter to
v7m_exception_taken(), so that the former can tell the latter that
it needs to ignore failures to write to the stack. We also plumb
the argument through to v7m_push_callee_stack(), which is where
the code to ignore the failures will be.
(Note that the v8M ARM pseudocode structures this slightly differently:
derived exceptions cause the attempt to process the original
exception to be abandoned; then at the top level it calls
DerivedLateArrival to prioritize the derived exception and call
TakeException from there. We choose to let the NVIC do the prioritization
and continue forward with a call to TakeException which will then
take either the original or the derived exception. The effect is
the same, but this structure works better for QEMU because we don't
have a convenient top level place to do the abandon-and-retry logic.)
Backports commit 0094ca70e165cfb69882fa2e100d935d45f1c983 from qemu
Currently armv7m_nvic_acknowledge_irq() does three things:
* make the current highest priority pending interrupt active
* return a bool indicating whether that interrupt is targeting
Secure or NonSecure state
* implicitly tell the caller which is the highest priority
pending interrupt by setting env->v7m.exception
We need to split these jobs, because v7m_exception_taken()
needs to know whether the pending interrupt targets Secure so
it can choose to stack callee-saves registers or not, but it
must not make the interrupt active until after it has done
that stacking, in case the stacking causes a derived exception.
Similarly, it needs to know the number of the pending interrupt
so it can read the correct vector table entry before the
interrupt is made active, because vector table reads might
also cause a derived exception.
Create a new armv7m_nvic_get_pending_irq_info() function which simply
returns information about the highest priority pending interrupt, and
use it to rearrange the v7m_exception_taken() code so we don't
acknowledge the exception until we've done all the things which could
possibly cause a derived exception.
Backports part of commit 6c9485188170e11ad31ce477c8ce200b8e8ce59d from qemu
In order to support derived exceptions (exceptions generated in
the course of trying to take an exception), we need to be able
to handle prioritizing whether to take the original exception
or the derived exception.
We do this by introducing a new function
armv7m_nvic_set_pending_derived() which the exception-taking code in
helper.c will call when a derived exception occurs. Derived
exceptions are dealt with mostly like normal pending exceptions, so
we share the implementation with the armv7m_nvic_set_pending()
function.
Note that the way we structure this is significantly different
from the v8M Arm ARM pseudocode: that does all the prioritization
logic in the DerivedLateArrival() function, whereas we choose to
let the existing "identify highest priority exception" logic
do the prioritization for us. The effect is the same, though.
Backports part of commit 5ede82b8ccb652382c106d53f656ed67997d76e8 from qemu
The instruction "moves" can select source and destination
address space (user or kernel). This patch modifies
all the load/store functions to be able to provide
the address space the caller wants to use instead
of using the current one. All the callers are modified
to provide the default address space to these functions.
Backports commit 54e1e0b5b5ce4fc76335b1fbbf09cb8fdd5ab89d from qemu
Only add MC68040 MMU page table processing and related
registers (Special Status Word, Translation Control Register,
User Root Pointer and Supervisor Root Pointer).
Transparent Translation Registers, DFC/SFC and pflush/ptest
will be added later.
Backports commit 88b2fef6c3c3b45ac0dc2196ace7248a09c8e41d from qemu
The MC68040 MMU provides the size of the access that
triggers the page fault.
This size is set in the Special Status Word which
is written in the stack frame of the access fault
exception.
So we need the size in m68k_cpu_unassigned_access() and
m68k_cpu_handle_mmu_fault().
To be able to do that, this patch modifies the prototype of
handle_mmu_fault handler, tlb_fill() and probe_write().
do_unassigned_access() already includes a size parameter.
This patch also updates handle_mmu_fault handlers and
tlb_fill() of all targets (only parameter, no code change).
Backports commit 98670d47cd8d63a529ff230fd39ddaa186156f8c from qemu
Rather than passing a regno to the helper, pass pointers to the
vector register directly. This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].
Backports commit e7c06c4e4c98c47899417f154df1f2ef4e8d09a0 from qemu
Rather than passing regnos to the helpers, pass pointers to the
vector registers directly. This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].
Backports commit b13708bbbdda54c7f7e28222b22453986c026391 from qemu
Rather than passing regnos to the helpers, pass pointers to the
vector registers directly. This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].
Backports commit 1a66ac61af45af04688d1d15896737310e366c06 from qemu
Commit ("3b39d734141a target/arm: Handle page table walk load failures
correctly") modified both versions of the page table walking code (i.e.,
arm_ldl_ptw and arm_ldq_ptw) to record the result of the translation in
a temporary 'data' variable so that it can be inspected before being
returned. However, arm_ldq_ptw() returns an uint64_t, and using a
temporary uint32_t variable truncates the upper bits, corrupting the
result. This causes problems when using more than 4 GB of memory in
a TCG guest. So use a uint64_t instead.
Backports commit 9aea1ea31af25fe344a88da086ff913cca09c667 from qemu
It is more typical to provide the ';' by the caller of a macro
than to embed it in the macro itself; this is because syntax
highlight engines can get confused if a macro is called without
a semicolon before the closing '}'.
Backports commit 94f5c480e9b5ce95394026b3f025816470e23eaf from qemu
Instead of ignoring the response from address_space_ld*()
(indicating an attempt to read a page table descriptor from
an invalid physical address), use it to report the failure
correctly.
Since this is another couple of locations where we need to
decide the value of the ARMMMUFaultInfo ea bit based on a
MemTxResult, we factor out that operation into a helper
function.
Backports commit 3b39d734141a71296d08af3d4c32f872fafd782e from qemu
For PMSAv7, the v7A/R Arm ARM defines that setting AP to 0b111
is an UNPREDICTABLE reserved combination. However, for v7M
this value is documented as having the same behaviour as 0b110:
read-only for both privileged and unprivileged. Accept this
value on an M profile core rather than treating it as a guest
error and a no-access page.
Backports commit 8638f1ad7403b63db880dadce38e6690b5d82b64 from qemu
Refactor disas_thumb2_insn() so that it generates the code for raising
an UNDEF exception for invalid insns, rather than returning a flag
which the caller must check to see if it needs to generate the UNDEF
code. This brings the function in to line with the behaviour of
disas_thumb_insn() and disas_arm_insn().
Backports commit 2eea841c11096e8dcc457b80e21f3fbdc32d2590 from qemu
ldxp loads two consecutive doublewords from memory regardless of CPU
endianness. On store, stlxp currently assumes to work with a 128bit
value and consequently switches order in big-endian mode. With this
change it packs the doublewords in reverse order in anticipation of the
128bit big-endian store operation interposing them so they end up in
memory in the right order. This makes it work for both MTTCG and !MTTCG.
It effectively implements the ARM ARM STLXP operation pseudo-code:
data = if BigEndian() then el1:el2 else el2:el1;
With this change an aarch64_be Linux 4.14.4 kernel succeeds to boot up
in system emulation mode.
Backports commit 0785557f8811133bd69be02aeccf018d47a26373 from qemu
This code is preventing the MMU debug code from displaying virtual
mappings of IO devices (anything that is not located in the RAM).
Before this patch, Qemu would output 0xffffffffffffffff (-1) as the
physical address corresponding to an IO device virtual address.
With this patch the intended physical address is displayed.
Backports commit 7e450a8f50ac12fc8f69b6ce555254c84efcf407 from qemu
Add the third stack pointer, the Interrupt Stack Pointer (ISP)
(680x0 only). This stack will be needed in softmmu mode.
Update movec to set/get the value of the three stacks.
Backports commit 6e22b28e22aa6ed1b8db6f24da2633868019d4c9 from qemu
Some cleanup, and allows SR to be moved from any addressing mode.
Previous code was wrong for coldfire: coldfire also allows to
use addressing mode to set SR/CCR. It only supports Data register
to get SR/CCR (move from)
Backports commit b6a21d8d8f69ac04fd6180e752a65d582c07e948 from qemu
The instruction traps if the CPU is not in
Supervisor state but the helper is empty because
there is no easy way to reset all the peripherals
without resetting the CPU itself.
Backports commit 0bdb2b3bf5660f892ddbfa09baea56cdca57ad1d from qemu
Add cache lines invalidate and cache lines push
as no-op operations, as we don't have cache.
These instructions are 68040 only.
Backports commit f58ed1c50add3e76331afdc92387c0da9dd9e443 from qemu
move16 moves the source line to the destination line. Lines are aligned
to 16-byte boundaries and are 16 bytes long.
Backports commit 9d4f0429f3dc1dc6c67de3eaa3106e6c1cfa1524 from qemu
chk and chk2 compare a value to boundaries, and
trigger a CHK exception if the value is out of bounds.
Backports commit 8bf6cbaf396a8b54b138bb8a7c3377f2868ed16e from qemu
As gen_helper_get_ccr() is able to compute CCR from cc_op and
flags, we don't need to flush flags before to call it.
flush_flags() and get_ccr() use COMPUTE_CCR() to compute
flags. get_ccr() computes CCR value,
whereas flush_flags update live cc_op and flags.
Backports commit 4131c242cc850aaf76e59d4c787d220f07850cf5 from qemu
And remove update_cc_op() from gen_exception() because there is
one in gen_jmp_im().
Backports commit 7cd7b5ca9be805e8a4ced4c07014c24e34812f27 from qemu
With no fixed array allocation, we can't overflow a buffer.
This will be important as optimizations related to host vectors
may expand the number of ops used.
Use QTAILQ to link the ops together.
Backports commit 15fa08f8451babc88d733bd411d4c94976f9d0f8 from qemu
cpu_restore_state officially supports being passed an address it can't
resolve the state for. As a result the checks in the helpers are
superfluous and can be removed. This makes the code consistent with
other users of cpu_restore_state.
Of course this does nothing to address what to do if cpu_restore_state
can't resolve the state but so far it seems this is handled elsewhere.
The change was made with included coccinelle script.
Backports commit 65255e8efdd5fca602bcc4ff61a879939ff75f4f from qemu
The first call of set_cc_op() in a new translation sequence
is done with old_op set to CC_OP_DYNAMIC (-1).
This will do an out of bound access to the array cc_op_live[].
We fix that by adding an entry in cc_op_live[] for CC_OP_DYNAMIC.
Backports commit 7deddf96e94f3e1eb3677db0ea7b53e61751b544 from qemu
Normally we create an address space for that CPU and pass that address
space into the function. Let's just do it inside to unify address space
creations. It'll simplify my next patch to rename those address spaces.
Backports commit 80ceb07a83375e3a0091591f96bd47bce2f640ce from qemu
These gcc warnings are fixed:
target/i386/translate.c:4461:12: warning:
variable 'prefixes' might be clobbered by 'longjmp' or 'vfork' [-Wclobbered]
target/i386/translate.c:4466:9: warning:
variable 'rex_w' might be clobbered by 'longjmp' or 'vfork' [-Wclobbered]
target/i386/translate.c:4466:16: warning:
variable 'rex_r' might be clobbered by 'longjmp' or 'vfork' [-Wclobbered]
Tested with x86_64-w64-mingw32-gcc from Debian stretch.
Backports commit a4926d99129a1d8072fc4681cd4efdb214f65ed4 from qemu
Intel IceLake cpu has added new cpu features,AVX512_VBMI2/GFNI/
VAES/VPCLMULQDQ/AVX512_VNNI/AVX512_BITALG. Those new cpu features
need expose to guest VM.
The bit definition:
CPUID.(EAX=7,ECX=0):ECX[bit 06] AVX512_VBMI2
CPUID.(EAX=7,ECX=0):ECX[bit 08] GFNI
CPUID.(EAX=7,ECX=0):ECX[bit 09] VAES
CPUID.(EAX=7,ECX=0):ECX[bit 10] VPCLMULQDQ
CPUID.(EAX=7,ECX=0):ECX[bit 11] AVX512_VNNI
CPUID.(EAX=7,ECX=0):ECX[bit 12] AVX512_BITALG
The release document ref below link:
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Backports commit aff9e6e46a343e1404498be4edd03db1112f0950 from qemu
Now that do_ats_write() is entirely in control of whether to
generate a 32-bit PAR or a 64-bit PAR, we can make it use the
correct (complicated) condition for doing so.
Backports commit 1313e2d7e2cd8b21741e0cf542eb09dfc4188f79 from qemu
All of the callers of get_phys_addr() and arm_tlb_fill() now ignore
the FSR values they return, so we can just remove the argument
entirely.
Backports commit bc52bfeb3be2052942b7dac8ba284f342ac9605b from qemu
In do_ats_write(), rather than using the FSR value from get_phys_addr(),
construct the PAR values using the information in the ARMMMUFaultInfo
struct. This allows us to create a PAR of the correct format regardless
of what the translation table format is.
For the moment we leave the condition for "when should this be a
64 bit PAR" as it was previously; this will need to be fixed to
properly support AArch32 Hyp mode.
Backports commit 5efe9ed45dec775ebe91ce72bd805ee780d16064 from qemu
Now that ARMMMUFaultInfo is guaranteed to have enough information
to construct a fault status code, we can pass it in to the
deliver_fault() function and let it generate the correct type
of FSR for the destination, rather than relying on the value
provided by get_phys_addr().
I don't think there are any cases the old code was getting
wrong, but this is more obviously correct.
Backports commit 681f9a89d201d7891e2c60dff5e5415d8f618518 from qemu
Make get_phys_addr_pmsav8() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.
Backports commit 3f551b5b7380ff131fe22944aa6f5b166aa13caf from qemu
Make get_phys_addr_pmsav7() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.
Backports commit 9375ad15338b24e06109071ac3a85df48a2cc2e6 from qemu
Make get_phys_addr_pmsav5() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.
Note that PMSAv5 does not define any guest-visible fault status
register, so the different "fsr" values we were previously
returning are entirely arbitrary. So we can just switch to using
the most appropriae fi->type values without worrying that we
need to special-case FaultInfo->FSC conversion for PMSAv5.
Backports commit 53a4e5c5b07b2f50c538511b74b0d3d4964695ea from qemu
Make get_phys_addr_v6() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.
Backports commit da909b2c23a68e57bbcb6be98229e40df606f0c8 from qemu
Make get_phys_addr_v6() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.
Backports commit f06cf243945ccb24cb9578304306ae7fcb4cf3fd from qemu
Make get_phys_addr_v5() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.
Backports commit f989983e8dc9be6bc3468c6dbe46fcb1501a740c from qemu
All the callers of arm_ldq_ptw() and arm_ldl_ptw() ignore the value
that those functions store in the fsr argument on failure: if they
return failure to their callers they will always overwrite the fsr
value with something else.
Remove the argument from these functions and S1_ptw_translate().
This will simplify removing fsr from the calling functions.
Backports commit 3795a6de9f7ec4a7e3dcb8bf02a88a014147b0b0 from qemu
Currently get_phys_addr() and its various subfunctions return
a hard-coded fault status register value for translation
failures. This is awkward because FSR values these days may
be either long-descriptor format or short-descriptor format.
Worse, the right FSR type to use doesn't depend only on the
translation table being walked -- some cases, like fault
info reported to AArch32 EL2 for some kinds of ATS operation,
must be in long-descriptor format even if the translation
table being walked was short format. We can't get those cases
right with our current approach.
Provide fields in the ARMMMUFaultInfo struct which allow
get_phys_addr() to provide sufficient information for a caller to
construct an FSR value themselves, and utility functions which do
this for both long and short format FSR values, as a first step in
switching get_phys_addr() and its children to only returning the
failure cause in the ARMMMUFaultInfo struct.
Backports commit 1fa498fe0de979030bd1f481046e9f1c5574a584 from qemu
Implement the TT instruction which queries the security
state and access permissions of a memory location.
Backports commit 5158de241b0fb344a6c948dfcbc4e611ab5fafbe from qemu
For the TT instruction we're going to need to do an MPU lookup that
also tells us which MPU region the access hit. This requires us
to do the MPU lookup without first doing the SAU security access
check, so pull the MPU lookup parts of get_phys_addr_pmsav8()
out into their own function.
The TT instruction also needs to know the MPU region number which
the lookup hit, so provide this information to the caller of the
MPU lookup code, even though get_phys_addr_pmsav8() doesn't
need to know it.
Backports commit 54317c0ff3a3c0f6b2c3a1d3c8b5d93686a86d24 from qemu
The TT instruction is going to need to look up the MMU index
for a specified security and privilege state. Refactor the
existing arm_v7m_mmu_idx_for_secstate() into a version that
lets you specify the privilege state and one that uses the
current state of the CPU.
Backports commit ec8e3340286a87d3924c223d60ba5c994549f796 from qemu
For M profile, we currently have an mmu index MNegPri for
"requested execution priority negative". This fails to
distinguish "requested execution priority negative, privileged"
from "requested execution priority negative, usermode", but
the two can return different results for MPU lookups. Fix this
by splitting MNegPri into MNegPriPriv and MNegPriUser, and
similarly for the Secure equivalent MSNegPri.
This takes us from 6 M profile MMU modes to 8, which means
we need to bump NB_MMU_MODES; this is OK since the point
where we are forced to reduce TLB sizes is 9 MMU modes.
(It would in theory be possible to stick with 6 MMU indexes:
{mpu-disabled,user,privileged} x {secure,nonsecure} since
in the MPU-disabled case the result of an MPU lookup is
always the same for both user and privileged code. However
we would then need to rework the TB flags handling to put
user/priv into the TB flags separately from the mmuidx.
Adding an extra couple of mmu indexes is simpler.)
Backports commit 62593718d77c06ad2b5e942727cead40775d2395 from qemu
When we added the ARMMMUIdx_MSUser MMU index we forgot to
add it to the case statement in regime_is_user(), so we
weren't treating it as unprivileged when doing MPU lookups.
Correct the omission.
Backports commit 871bec7c44a453d9cab972ce1b5d12e1af0545ab from qemu
In ARMv7M the CPU ignores explicit writes to CONTROL.SPSEL
in Handler mode. In v8M the behaviour is slightly different:
writes to the bit are permitted but will have no effect.
We've already done the hard work to handle the value in
CONTROL.SPSEL being out of sync with what stack pointer is
actually in use, so all we need to do to fix this last loose
end is to update the condition we use to guard whether we
call write_v7m_control_spsel() on the register write.
Backports commit 83d7f86d3d27473c0aac79c1baaa5c2ab01b02d9 from qemu
For v8M it is possible for the CONTROL.SPSEL bit value and the
current stack to be out of sync. This means we need to update
the checks used in reads and writes of the PSP and MSP special
registers to use v7m_using_psp() rather than directly checking
the SPSEL bit in the control register.
Backports commit 1169d3aa5b19adca9384d954d80e1f48da388284 from qemu
EPYC-IBPB is a copy of the EPYC CPU model with
just CPUID_8000_0008_EBX_IBPB added.
Backports commit 8ebfafa796ca0cb2b035a7f06f836a675d8b48be from qemu
The new MSR IA32_SPEC_CTRL MSR was introduced by a recent Intel
microcode updated and can be used by OSes to mitigate
CVE-2017-5715. Unfortunately we can't change the existing CPU
models without breaking existing setups, so users need to
explicitly update their VM configuration to use the new *-IBRS
CPU model if they want to expose IBRS to guests.
The new CPU models are simple copies of the existing CPU models,
with just CPUID_7_0_EDX_SPEC_CTRL added and model_id updated.
Backports commit 61efbbf869293f1deb9ee39d44bd4e635de59fa7 from qemu
Add the new feature word and the "ibpb" feature flag.
Based on a patch by Paolo Bonzini.
Backports commit 1ade973f5202404e772aae7b1acd331270d246dc from qemu
It is valid to have a 48-character model ID on CPUID, however the
definition of X86CPUDefinition::model_id is char[48], which can
make the compiler drop the null terminator from the string.
If a CPU model happens to have 48 bytes on model_id, "-cpu help"
will print garbage and the object_property_set_str() call at
x86_cpu_load_def() will read data outside the model_id array.
We could increase the array size to 49, but this would mean the
compiler would not issue a warning if a 49-char string is used by
mistake for model_id.
To make things simpler, simply change model_id to be const char*,
and validate the string length using an assert() on
x86_register_cpudef_type().
Backports commit 4b220d88ba76fb2623ce4b8ba1f1eea66b82144e from qemu
In commit e3af7c788b73a6495eb9d94992ef11f6ad6f3c56 we
replaced direct calls to to cpu_ld*_code() with calls
to the x86_ld*_code() wrappers which incorporate an
advance of s->pc. Unfortunately we didn't notice that
in one place the old code was deliberately not incrementing
s->pc:
@@ -4501,7 +4528,7 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
static const int pp_prefix[4] = {
0, PREFIX_DATA, PREFIX_REPZ, PREFIX_REPNZ
};
- int vex3, vex2 = cpu_ldub_code(env, s->pc);
+ int vex3, vex2 = x86_ldub_code(env, s);
if (!CODE64(s) && (vex2 & 0xc0) != 0xc0) {
/* 4.1.4.6: In 32-bit mode, bits [7:6] must be 11b,
This meant we were mishandling this set of instructions.
Remove the manual advance of s->pc for the "is VEX" case
(which is now done by x86_ldub_code()) and instead rewind
PC in the case where we decide that this isn't really VEX.
Backports commit 817a9fcba8043faa467929e7b0193df6bdc92211 from qemu
The refactoring of commit 296e5a0a6c3935 has a nasty bug:
it accidentally dropped the generation of code to raise
the UNDEF exception when disas_thumb2_insn() returns nonzero.
This means that 32-bit Thumb2 instruction patterns that
ought to UNDEF just act like nops instead. This is likely
to break any number of things, including the kernel's "disable
the FPU and use the UNDEF exception to identify when to turn
it back on again" trick.
Backports commit 7472e2efb049ea65a6a5e7261b78ebf5c561bc2f from qemu
In do_ats_write(), rather than using extended_addresses_enabled() to
decide whether the value we get back from get_phys_addr() is a 64-bit
format PAR or a 32-bit one, use arm_s1_regime_using_lpae_format().
This is not really the correct answer, because the PAR format
depends on the AT instruction being used, not just on the
translation regime. However getting this correct requires a
significant refactoring, so that get_phys_addr() returns raw
information about the fault which the caller can then assemble
into a suitable FSR/PAR/syndrome for its purposes, rather than
get_phys_addr() returning a pre-formatted FSR.
However this change at least improves the situation by making
the PAR work correctly for address translation operations done
at AArch64 EL2 on the EL2 translation regime. In particular,
this is necessary for Xen to be able to run in our emulation,
so this seems like a safer interim fix given that we are in freeze.
Backports commit 50cd71b0d347c74517dcb7da447fe657fca57d9c from qemu
The CPU ID registers ID_AA64PFR0_EL1, ID_PFR1_EL1 and ID_PFR1
have a field for reporting presence of GICv3 system registers.
We need to report this field correctly in order for Xen to
work as a guest inside QEMU emulation. We mustn't incorrectly
claim the sysregs exist when they don't, though, or Linux will
crash.
Unfortunately the way we've designed the GICv3 emulation in QEMU
puts the system registers as part of the GICv3 device, which
may be created after the CPU proper has been realized. This
means that we don't know at the point when we define the ID
registers what the correct value is. Handle this by switching
them to calling a function at runtime to read the value, where
we can fill in the GIC field appropriately.
Backports commit 96a8b92ed8f02d5e86ad380d3299d9f41f99b072 from qemu
We use raw memory primitives along the !parallel_cpus paths in order to
simplify the endianness handling. Because of that, we did not benefit
from the generic changes to cpu_ldst_user_only_template.h.
The simplest fix is to manipulate helper_retaddr here.
Backports commit 3bdb5fcc9a08a9a47ce30c4e0c2d64c95190b49d from qemu
Fixes the following warning when compiling with gcc 5.4.0 with -O1
optimizations and --enable-debug:
target/arm/translate-a64.c: In function ‘aarch64_tr_translate_insn’:
target/arm/translate-a64.c:2361:8: error: ‘post_index’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (!post_index) {
^
target/arm/translate-a64.c:2307:10: note: ‘post_index’ was declared here
bool post_index;
^
target/arm/translate-a64.c:2386:8: error: ‘writeback’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (writeback) {
^
target/arm/translate-a64.c:2308:10: note: ‘writeback’ was declared here
bool writeback;
^
Note that idx comes from selecting 2 bits, and therefore its value
can be at most 3.
Backports commit 5ca66278c859bb1ded243755aeead2be6992ce73 from qemu
For AArch32 LDREXD and STREXD, architecturally the 32-bit word at the
lowest address is always Rt and the one at addr+4 is Rt2, even if the
CPU is big-endian. Our implementation does these with a single
64-bit store, so if we're big-endian then we need to put the two
32-bit halves together in the opposite order to little-endian,
so that they end up in the right places. We were trying to do
this with the gen_aa32_frob64() function, but that is not correct
for the usermode emulator, because there there is a distinction
between "load a 64 bit value" (which does a BE 64-bit access
and doesn't need swapping) and "load two 32 bit values as one
64 bit access" (where we still need to do the swapping, like
system mode BE32).
Backports commit 3448d47b3172015006b79197eb5a69826c6a7b6d from qemu
On a successful address translation instruction, PAR is supposed to
contain cacheability and shareability attributes determined by the
translation. We previously returned 0 for these bits (in line with the
general strategy of ignoring caches and memory attributes), but some
guest OSes may depend on them.
This patch collects the attribute bits in the page-table walk, and
updates PAR with the correct attributes for all LPAE translations.
Short descriptor formats still return 0 for these bits, as in the
prior implementation.
Backports commit 5b2d261d60caf9d988d91ca1e02392d6fc8ea104 from qemu
WFI/E are often, but not always, 4 bytes long. When they are, we need to
set ARM_EL_IL_SHIFT in the syndrome register.
Pass the instruction length to HELPER(wfi), use it to decrement pc
appropriately and to pass an is_16bit flag to syn_wfx, which sets
ARM_EL_IL_SHIFT if needed.
Set dc->insn in both arm_tr_translate_insn and thumb_tr_translate_insn.
Backports commit 58803318e5a546b2eb0efd7a053ed36b6c29ae6f from qemu
When we used structures for TCGv_*, we needed a macro in order to
perform a comparison. Now that we use pointers, this is just clutter
Backports commit 11f4e8f8bfaa2caaab24bef6bbbb8a0205015119 from qemu
The GET and MAKE functions weren't really specific enough.
We now have a full complement of functions that convert exactly
between temporaries, arguments, tcgv pointers, and indices.
The target/sparc change is also a bug fix, which would have affected
a host that defines TCG_TARGET_HAS_extr[lh]_i64_i32, i.e. MIPS64.
Backports commit dc41aa7d34989b552efe712ffe184236216f960b from qemu
Rather than have a separate buffer of 10*max_ops entries,
give each opcode 10 entries. The result is actually a bit
smaller and should have slightly more cache locality.
Backports commit 75e8b9b7aa0b95a761b9add7e2f09248b101a392 from qemu
Besides being more correct, arbitrarily long instruction allow the
generation of a translation block that spans three pages. This
confuses the generator and even allows ring 3 code to poison the
translation block cache and inject code into other processes that are
in guest ring 3.
This is an improved (and more invasive) fix for commit 30663fd ("tcg/i386:
Check the size of instruction being translated", 2017-03-24). In addition
to being more precise (and generating the right exception, which is #GP
rather than #UD), it distinguishes better between page faults and too long
instructions, as shown by this test case:
int main()
{
char *x = mmap(NULL, 8192, PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_PRIVATE|MAP_ANON, -1, 0);
memset(x, 0x66, 4096);
x[4096] = 0x90;
x[4097] = 0xc3;
char *i = x + 4096 - 15;
mprotect(x + 4096, 4096, PROT_READ|PROT_WRITE);
((void(*)(void)) i) ();
}
... which produces a #GP without the mprotect, and a #PF with it.
Backports commit b066c5375737ad0d630196dab2a2b329515a1d00 from qemu
These take care of advancing s->pc, and will provide a unified point
where to check for the 15-byte instruction length limit.
Backports commit e3af7c788b73a6495eb9d94992ef11f6ad6f3c56 from qemu
The common situation of the SG instruction is that it is
executed from S&NSC memory by a CPU in NS state. That case
is handled by v7m_handle_execute_nsc(). However the instruction
also has defined behaviour in a couple of other cases:
* SG instruction in NS memory (behaves as a NOP)
* SG in S memory but CPU already secure (clears IT bits and
does nothing else)
* SG instruction in v8M without Security Extension (NOP)
These can be implemented in translate.c.
Backports commit 76eff04d166b8fe747adbe82de8b7e060e668ff9 from qemu
A few Thumb instructions are always unconditional even inside an
IT block (as opposed to being UNPREDICTABLE if used inside an
IT block): BKPT, the v8M SG instruction, and the A profile
HLT (debug halt) instruction.
This means we need to suppress the jump-over-instruction-on-condfail
code generation (though the IT state still advances as usual and
subsequent insns in the IT block may be conditional).
Backports commit dcf14dfb704519846f396a376339ebdb93eaf049 from qemu
Recent changes have left insn_crosses_page() more complicated
than it needed to be:
* it's only called from thumb_tr_translate_insn() so we know
for certain that we're looking at a Thumb insn
* the caller's check for dc->pc >= dc->next_page_start - 3
means that dc->pc can't possibly be 4 aligned, so there's
no need to check that (the check was partly there to ensure
that we didn't treat an ARM insn as Thumb, I think)
* we now have thumb_insn_is_16bit() which lets us do a precise
check of the length of the next insn, rather than opencoding
an inaccurate check
Simplify it down to just loading the first half of the insn
and calling thumb_insn_is_16bit() on it.
Backports commit 5b8d7289e9e92a0d7bcecb93cd189e245fef10cd from qemu
Refactor the Thumb decode to do the loads of the instruction words at
the top level rather than only loading the second half of a 32-bit
Thumb insn in the middle of the decode.
This is simple apart from the awkward case of Thumb1, where the
BL/BLX prefix and suffix instructions live in what in Thumb2 is the
32-bit insn space. To handle these we decode enough to identify
whether we're looking at a prefix/suffix that we handle as a 16 bit
insn, or a prefix that we're going to merge with the following suffix
to consider as a 32 bit insn. The translation of the 16 bit cases
then moves from disas_thumb2_insn() to disas_thumb_insn().
The refactoring has the benefit that we don't need to pass the
CPUARMState* down into the decoder code any more, but the major
reason for doing this is that some Thumb instructions must be always
unconditional regardless of the IT state bits, so we need to know the
whole insn before we emit the "skip this insn if the IT bits and cond
state tell us to" code. (The always unconditional insns are BKPT,
HLT and SG; the last of these is 32 bits.)
Backports commit 296e5a0a6c393553079a641c50521ae33ff89324 from qemu
The code which implements the Thumb1 split BL/BLX instructions
is guarded by a check on "not M or THUMB2". All we really need
to check here is "not THUMB2" (and we assume that elsewhere too,
eg in the ARCH(6T2) test that UNDEFs the Thumb2 insns).
This doesn't change behaviour because all M profile cores
have Thumb2 and so ARM_FEATURE_M implies ARM_FEATURE_THUMB2.
(v6M implements a very restricted subset of Thumb2, but we
can cross that bridge when we get to it with appropriate
feature bits.)
Backports commit 6b8acf256df09c8a8dd7dcaa79b06eaff4ad63f7 from qemu
Secure function return happens when a non-secure function has been
called using BLXNS and so has a particular magic LR value (either
0xfefffffe or 0xfeffffff). The function return via BX behaves
specially when the new PC value is this magic value, in the same
way that exception returns are handled.
Adjust our BX excret guards so that they recognize the function
return magic number as well, and perform the function-return
unstacking in do_v7m_exception_exit().
Backports commit d02a8698d7ae2bfed3b11fe5b064cb0aa406863b from qemu
Implement the SG instruction, which we emulate 'by hand' in the
exception handling code path.
Backports commit 333e10c51ef5876ced26f77b61b69ce0f83161a9 from qemu
Add the M profile secure MMU index values to the switch in
get_a32_user_mem_index() so that LDRT/STRT work correctly
rather than asserting at translate time.
Backports commit b9f587d62cebed427206539750ebf59bde4df422 from qemu
It is unlikely that we will ever want to call this helper passing
an argument other than the current PC. So just remove the argument,
and use the pc we already get from cpu_get_tb_cpu_state.
This change paves the way to having a common "tb_lookup" function.
Backports commit 7f11636dbee89b0e4d03e9e2b96e14649a7db778 from qemu
It looks like there was a transcription error when writing this code
initially. The code previously only decoded src or dst of rax. This
resolves
https://bugs.launchpad.net/qemu/+bug/1719984.
Backports commit e0dd5fd41a1a38766009f442967fab700d2d0550 from qemu
For the SG instruction and secure function return we are going
to want to do memory accesses using the MMU index of the CPU
in secure state, even though the CPU is currently in non-secure
state. Write arm_v7m_mmu_idx_for_secstate() to do this job,
and use it in cpu_mmu_index().
Backports commit b81ac0eb6315e602b18439961e0538538e4aed4f from qemu
In cpu_mmu_index() we try to do this:
if (env->v7m.secure) {
mmu_idx += ARMMMUIdx_MSUser;
}
but it will give the wrong answer, because ARMMMUIdx_MSUser
includes the 0x40 ARM_MMU_IDX_M field, and so does the
mmu_idx we're adding to, and we'll end up with 0x8n rather
than 0x4n. This error is then nullified by the call to
arm_to_core_mmu_idx() which masks out the high part, but
we're about to factor out the code that calculates the
ARMMMUIdx values so it can be used without passing it through
arm_to_core_mmu_idx(), so fix this bug first.
Backports commit fe768788d29597ee56fc11ba2279d502c2617457 from qemu
Implement the security attribute lookups for memory accesses
in the get_phys_addr() functions, causing these to generate
various kinds of SecureFault for bad accesses.
The major subtlety in this code relates to handling of the
case when the security attributes the SAU assigns to the
address don't match the current security state of the CPU.
In the ARM ARM pseudocode for validating instruction
accesses, the security attributes of the address determine
whether the Secure or NonSecure MPU state is used. At face
value, handling this would require us to encode the relevant
bits of state into mmu_idx for both S and NS at once, which
would result in our needing 16 mmu indexes. Fortunately we
don't actually need to do this because a mismatch between
address attributes and CPU state means either:
* some kind of fault (usually a SecureFault, but in theory
perhaps a UserFault for unaligned access to Device memory)
* execution of the SG instruction in NS state from a
Secure & NonSecure code region
The purpose of SG is simply to flip the CPU into Secure
state, so we can handle it by emulating execution of that
instruction directly in arm_v7m_cpu_do_interrupt(), which
means we can treat all the mismatch cases as "throw an
exception" and we don't need to encode the state of the
other MPU bank into our mmu_idx values.
This commit doesn't include the actual emulation of SG;
it also doesn't include implementation of the IDAU, which
is a per-board way to specify hard-coded memory attributes
for addresses, which override the CPU-internal SAU if they
specify a more secure setting than the SAU is programmed to.
Backports commit 35337cc391245f251bfb9134f181c33e6375d6c1 from qemu
Implement the register interface for the SAU: SAU_CTRL,
SAU_TYPE, SAU_RNR, SAU_RBAR and SAU_RLAR. None of the
actual behaviour is implemented here; registers just
read back as written.
When the CPU definition for Cortex-M33 is eventually
added, its initfn will set cpu->sau_sregion, in the same
way that we currently set cpu->pmsav7_dregion for the
M3 and M4.
Number of SAU regions is typically a configurable
CPU parameter, but this patch doesn't provide a
QEMU CPU property for it. We can easily add one when
we have a board that requires it.
Backports commit 9901c576f6c02d43206e5faaf6e362ab7ea83246 from qemu
Add support for v8M and in particular the security extension
to the exception entry code. This requires changes to:
* calculation of the exception-return magic LR value
* push the callee-saves registers in certain cases
* clear registers when taking non-secure exceptions to avoid
leaking information from the interrupted secure code
* switch to the correct security state on entry
* use the vector table for the security state we're targeting
Backports commit d3392718e1fcf0859fb7c0774a8e946bacb8419c from qemu
For v8M, exceptions from Secure to Non-Secure state will save
callee-saved registers to the exception frame as well as the
caller-saved registers. Add support for unstacking these
registers in exception exit when necessary.
Backports commit 907bedb3f3ce134c149599bd9cb61856d811b8ca from qemu
In v8M, more bits are defined in the exception-return magic
values; update the code that checks these so we accept
the v8M values when the CPU permits them.
Backports commit bfb2eb52788b9605ef2fc9bc72683d4299117fde from qemu
Add the new M profile Secure Fault Status Register
and Secure Fault Address Register.
Backports commit bed079da04dd9e0e249b9bc22bca8dce58b67f40 from qemu
In the v8M architecture, return from an exception to a PC which
has bit 0 set is not UNPREDICTABLE; it is defined that bit 0
is discarded [R_HRJH]. Restrict our complaint about this to v7M.
Backports commit 4e4259d3c574a8e89c3af27bcb84bc19a442efb1 from qemu
Attempting to do an exception return with an exception frame that
is not 8-aligned is UNPREDICTABLE in v8M; warn about this.
(It is not UNPREDICTABLE in v7M, and our implementation can
handle the merely-4-aligned case fine, so we don't need to
do anything except warn.)
Backports commit cb484f9a6e790205e69d9a444c3e353a3a1cfd84 from qemu
ARM v8M specifies that the INVPC usage fault for mismatched
xPSR exception field and handler mode bit should be checked
before updating the PSR and SP, so that the fault is taken
with the existing stack frame rather than by pushing a new one.
Perform this check in the right place for v8M.
Since v7M specifies in its pseudocode that this usage fault
check should happen later, we have to retain the original
code for that check rather than being able to merge the two.
(The distinction is architecturally visible but only in
very obscure corner cases like attempting an invalid exception
return with an exception frame in read only memory.)
Backports commit 224e0c300a0098fb577a03bd29d774d0769f632a from qemu
On exception return for v8M, the SPSEL bit in the EXC_RETURN magic
value should be restored to the SPSEL bit in the CONTROL register
banked specified by the EXC_RETURN.ES bit.
Add write_v7m_control_spsel_for_secstate() which behaves like
write_v7m_control_spsel() but allows the caller to specify which
CONTROL bank to use, reimplement write_v7m_control_spsel() in
terms of it, and use it in exception return.
Backports commit 3f0cddeee1f266d43c956581f3050058360a810d from qemu
Now that we can handle the CONTROL.SPSEL bit not necessarily being
in sync with the current stack pointer, we can restore the correct
security state on exception return. This happens before we start
to read registers off the stack frame, but after we have taken
possible usage faults for bad exception return magic values and
updated CONTROL.SPSEL.
Backports commit 3919e60b6efd9a86a0e6ba637aa584222855ac3a from qemu
In the v7M architecture, there is an invariant that if the CPU is
in Handler mode then the CONTROL.SPSEL bit cannot be nonzero.
This in turn means that the current stack pointer is always
indicated by CONTROL.SPSEL, even though Handler mode always uses
the Main stack pointer.
In v8M, this invariant is removed, and CONTROL.SPSEL may now
be nonzero in Handler mode (though Handler mode still always
uses the Main stack pointer). In preparation for this change,
change how we handle this bit: rename switch_v7m_sp() to
the now more accurate write_v7m_control_spsel(), and make it
check both the handler mode state and the SPSEL bit.
Note that this implicitly changes the point at which we switch
active SP on exception exit from before we pop the exception
frame to after it.
Backports commit de2db7ec894f11931932ca78cd14a8d2b1389d5b from qemu
Currently our M profile exception return code switches to the
target stack pointer relatively early in the process, before
it tries to pop the exception frame off the stack. This is
awkward for v8M for two reasons:
* in v8M the process vs main stack pointer is not selected
purely by the value of CONTROL.SPSEL, so updating SPSEL
and relying on that to switch to the right stack pointer
won't work
* the stack we should be reading the stack frame from and
the stack we will eventually switch to might not be the
same if the guest is doing strange things
Change our exception return code to use a 'frame pointer'
to read the exception frame rather than assuming that we
can switch the live stack pointer this early.
Backports commit 5b5223997c04b769bb362767cecb5f7ec382c5f0 from qemu
This properly forwards SMC events to EL2 when PSCI is provided by QEMU
itself and, thus, ARM_FEATURE_EL3 is off.
Found and tested with the Jailhouse hypervisor. Solution based on
suggestions by Peter Maydell.
Backports commit 77077a83006c3c9bdca496727f1735a3c5c5355d from qemu
In the A64 decoder, we have a lot of references to section numbers
from version A.a of the v8A ARM ARM (DDI0487). This version of the
document is now long obsolete (we are currently on revision B.a),
and various intervening versions renumbered all the sections.
The most recent B.a version of the document doesn't assign
section numbers at all to the individual instruction classes
in the way that the various A.x versions did. The simplest thing
to do is just to delete all the out of date C.x.x references.
Backports commit 4ce31af4aeb8471f6a913de7c59d3bde1fc4f03d from qemu
Now that we have a banked FAULTMASK register and banked exceptions,
we can implement the correct check in cpu_mmu_index() for whether
the MPU_CTRL.HFNMIENA bit's effect should apply. This bit causes
handlers which have requested a negative execution priority to run
with the MPU disabled. In v8M the test has to check this for the
current security state and so takes account of banking.
Backports relevant part of commit 5d4791991d4de12e83d44738417c9e964167b6e8 from qemu
In v8M the MSR and MRS instructions have extra register value
encodings to allow secure code to access the non-secure banked
version of various special registers.
(We don't implement the MSPLIM_NS or PSPLIM_NS aliases, because
we don't currently implement the stack limit registers at all.)
Backports commit 50f11062d4c896408731d6a286bcd116d1e08465 from qemu
Although none of the existing macro call-sites were broken,
it's always better to write macros that properly parenthesize
arguments that can be complex expressions, so that the intended
order of operations is not broken.
Backports commit 2a2be359c4335607c7f746cf27c412c08ab89aff from qemu
now cpu_mips_init() reimplements subset of cpu_generic_init()
tasks, so just drop it and use cpu_generic_init() directly.
Backports commit c4c8146cfd0fc3f95418fbc82a2eded594675022 from qemu
Register separate QOM types for each mips cpu model,
so it would be possible to reuse generic CPU creation
routines.
Backports commit 41da212c9ce9482fcfd490170c2611470254f8dc from qemu
This changes the order between cpu_mips_realize_env() and
cpu_exec_initfn(), but cpu_exec_initfn() don't have anything that
depends on cpu_mips_realize_env() being called first.
Backports commit df4dc10284e1d871db8adb512816a561473ffe3e from qemu
no logical change, only code movement (and fix a comment typo).
Backports commit 26aa3d9aecbb6fe9bce808a1d127191bdf3cc3d2 from qemu
Also backports commit 5502b66fc7d0bebd08b9b7017cb7e8b5261c3a2d
Starting with Windows Server 2012 and Windows 8, if
CPUID.40000005.EAX contains a value of -1, Windows assumes specific
limit to the number of VPs. In this case, Windows Server 2012
guest VMs may use more than 64 VPs, up to the maximum supported
number of processors applicable to the specific Windows
version being used.
https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs
For compatibility, Let's introduce a new property for X86CPU,
named "x-hv-max-vps" as Eduardo's suggestion, and set it
to 0x40 before machine 2.10.
(The "x-" prefix indicates that the property is not supposed to
be a stable user interface.)
Backports relevant parts of commit 6c69dfb67e84747cf071958594d939e845dfcc0c from qemu
The SSE4.1 phminposuw instruction finds the minimum 16-bit element in
the source vector, putting the value of that element in the low 16
bits of the destination vector, the index of that element in the next
three bits and zeroing the rest of the destination. The helper for
this operation fills the destination from high to low, meaning that
when the source and destination are the same register, the minimum
source element can be overwritten before it is copied to the
destination. This patch fixes it to fill the destination from low to
high instead, so the minimum source element is always copied first.
This fixes one gcc test failure in my GCC 6-based testing (and so
concludes the present sequence of patches, as I don't have any further
gcc test failures left in that testing that I attribute to QEMU bugs).
Backports commit aa406feadfc5b095ca147ec56d6187c64be015a7 from qemu
One of the cases of the SSE4.2 pcmpestri / pcmpestrm / pcmpistri /
pcmpistrm instructions does a substring search. The implementation of
this case in the pcmpxstrx helper is incorrect. The operation in this
case is a search for a string (argument d to the helper) in another
string (argument s to the helper); if a copy of d at a particular
position would run off the end of s, the resulting output bit should
be 0 whether or not the strings match in the region where they
overlap, but the QEMU implementation was wrongly comparing only up to
the point where s ends and counting it as a match if an initial
segment of d matched a terminal segment of s. Here, "run off the end
of s" means that some byte of d would overlap some byte outside of s;
thus, if d has zero length, it is considered to match everywhere,
including after the end of s. This patch fixes the implementation to
correspond with the proper instruction semantics. This fixes four gcc
test failures in my GCC 6-based testing.
Backports commit ae35eea7e4a9f21dd147406dfbcd0c4c6aaf2a60 from qemu
The SSE4.1 packusdw instruction combines source and destination
vectors of signed 32-bit integers into a single vector of unsigned
16-bit integers, with unsigned saturation. When the source and
destination are the same register, this means each 32-bit element of
that register is used twice as an input, to produce two of the 16-bit
output elements, and so if the operation is carried out
element-by-element in-place, no matter what the order in which it is
applied to the elements, the first element's operation will overwrite
some future input. The helper for packssdw avoids this issue by
computing the result in a local temporary and copying it to the
destination at the end; this patch fixes the packusdw helper to do
likewise. This fixes three gcc test failures in my GCC 6-based
testing.
Backports commit 80e19606215d4df370dfe8fe21c558a129f00f0b from qemu
It turns out that my recent fix to set rip_offset when emulating some
SSE4.1 instructions needs generalizing to cover a wider class of
instructions. Specifically, every instruction in the sse_op_table7
table, coming from various instruction set extensions, has an 8-bit
immediate operand that comes after any memory operand, and so needs
rip_offset set for correctness if there is a memory operand that is
rip-relative, and my patch only set it for a subset of those
instructions. This patch moves the rip_offset setting to cover the
wider class of instructions, so fixing 9 further gcc testsuite
failures in my GCC 6-based testing. (I do not know whether there
might be still further classes of instructions missing this setting.)
Backports commit c6a8242915328cda0df0fbc0803da3448137e614 from qemu
The SSE4.1 pmovsx* and pmovzx* instructions take packed 1-byte, 2-byte
or 4-byte inputs and sign-extend or zero-extend them to a wider vector
output. The associated helpers for these instructions do the
extension on each element in turn, starting with the lowest. If the
input and output are the same register, this means that all the input
elements after the first have been overwritten before they are read.
This patch makes the helpers extend starting with the highest element,
not the lowest, to avoid such overwriting. This fixes many GCC test
failures (161 in the gcc testsuite in my GCC 6-based testing) when
testing with a default CPU setting enabling those instructions.
Backports commit c6a56c8e990b213a1638af2d34352771d5fa4d9c from qemu
Instead of copying addr to a local temp, reuse the value (which we
have just compared as equal) already saved in cpu_exclusive_addr.
Backports commit 37e29a64254bf82a1901784fcca17c25f8164c2f from qemu
Previously when single stepping through ERET instruction via GDB
would result in debugger entering the "next" PC after ERET instruction.
When debugging in kernel mode, this will also cause unintended behavior,
because debugger will try to access memory from EL0 point of view.
Backports commit dddbba9943ef6a81c8702e4a50cb0a8b1a4201fe from qemu
In the v7M and v8M ARM ARM, the magic exception return values are
referred to as EXC_RETURN values, and in QEMU we use V7M_EXCRET_*
constants to define bits within them. Rename the 'type' variable
which holds the exception return value in do_v7m_exception_exit()
to excret, making it clearer that it does hold an EXC_RETURN value.
Backports commit 351e527a613147aa2a2e6910f92923deef27ee48 from qemu
The exception-return magic values get some new bits in v8M, which
makes some bit definitions for them worthwhile.
We don't use the bit definitions for the switch on the low bits
which checks the return type for v7M, because this is defined
in the v7M ARM ARM as a set of valid values rather than via
per-bit checks.
Backports commit 4d1e7a4745c050f7ccac49a1c01437526b5130b5 from qemu
In do_v7m_exception_exit(), there's no need to force the high 4
bits of 'type' to 1 when calling v7m_exception_taken(), because
we know that they're always 1 or we could not have got to this
"handle return to magic exception return address" code. Remove
the unnecessary ORs.
Backports commit 7115cdf5782922611bcc44c89eec5990db7f6466 from qemu
For a bus fault, the M profile BFSR bit PRECISERR means a bus
fault on a data access, and IBUSERR means a bus fault on an
instruction access. We had these the wrong way around; fix this.
Backports commit c6158878650c01b2c753b2ea7d0967c8fe5ca59e from qemu
For M profile we must clear the exclusive monitor on reset, exception
entry and exception exit. We weren't doing any of these things; fix
this bug.
Backports commit dc3c4c14f0f12854dbd967be3486f4db4e66d25b from qemu
For M profile we must clear the exclusive monitor on reset, exception
entry and exception exit. We weren't doing any of these things; fix
this bug.
Backports commit dc3c4c14f0f12854dbd967be3486f4db4e66d25b from qemu
Use a symbolic constant M_REG_NUM_BANKS for the array size for
registers which are banked by M profile security state, rather
than hardcoding lots of 2s.
Backports commit 4a16724f06ead684a5962477a557c26c677c2729 from qemu
