V flag for subtraction is:
v = (res ^ src1) & (src1 ^ src2)
(see COMPUTE_CCR() in target/m68k/helper.c)
But gen_flush_flags() uses:
v = (res ^ src2) & (src1 ^ src2)
The problem has been found with the following program:
.global _start
_start:
move.l #-2147483648,%d0
subq.l #1,%d0
jvc 1f
move.l #1,%d1
move.l #1,%d0
trap #0
1:
move.l #0,%d1
move.l #1,%d0
trap #0
It works fine (exit(1)) on real hardware, and with "-singlestep".
"-singlestep" uses gen_helper_flush_flags(), whereas
without "-singlestep", V flag is computed directly in
gen_flush_flags().
This patch updates gen_flush_flags() to have the same result
as with gen_helper_flush_flags().
Backports commit 043b936ef6fe53396b3c6b8f5562ea3e238a071d from qemu
Running Windows with icount causes a crash in instruction of write cr.
This patch fixes it.
Reading and writing cr cause an icount read because there are called
cpu_get_apic_tpr and cpu_set_apic_tpr functions. So, there is need
gen_io_start()/gen_io_end() calls.
Backports commit 5b003a40bb1ab14d0398e91f03393d3c6b9577cd from qemu
This speeds up SMM switches. Later on it may remove the need to take
the BQL, and it may also allow to reuse code between TCG and KVM.
Backports commit f8c45c6550b9ff1e1f0b92709ff3213a79870879 from qemu
Instead of unconditionally exiting to the exec loop, use the
gen_jr helper to jump to the target if it is valid.
Perf impact: see next commit's log.
Backports commit fe62089563ffc6a42f16ff28a6b6be34d2697766 from qemu
Instead of unconditionally exiting to the exec loop, use the
lookup_and_goto_ptr helper to jump to the target if it is valid.
Perf impact: see next commit's log.
Backports commit 7ad55b4ffd982c80f26f7f3658138d94cdc678e8 from qemu
The cp15, CRn=15, opc1=0, CRm=5, opc2=0 instruction invalidates all the
data cache on the cortex-r5. Implementing it as a NOP.
Backports commit 95e9a242e2a393c7d4e5cc04340e39c3a9420f03 from qemu
M profile doesn't implement ARM, and the architecturally required
behaviour for attempts to execute with the Thumb bit clear is to
generate a UsageFault with the CFSR INVSTATE bit set. We were
incorrectly implementing this as generating an UNDEFINSTR UsageFault;
fix this.
Backports commit e13886e3a790b52f0b2e93cb5e84fdc2ada5471a from qemu
Implement the exception return consistency checks
described in the v7M pseudocode ExceptionReturn().
Inspired by a patch from Michael Davidsaver's series, but
this is a reimplementation from scratch based on the
ARM ARM pseudocode.
Backports commit aa488fe3bb5460c6675800ccd80f6dccbbd70159 from qemu
Extract the code from the tail end of arm_v7m_do_interrupt() which
enters the exception handler into a pair of utility functions
v7m_exception_taken() and v7m_push_stack(), which correspond roughly
to the pseudocode PushStack() and ExceptionTaken().
This also requires us to move the arm_v7m_load_vector() utility
routine up so we can call it.
Handling illegal exception returns has some cases where we want to
take a UsageFault either on an existing stack frame or with a new
stack frame but with a specific LR value, so we want to be able to
call these without having to go via arm_v7m_cpu_do_interrupt().
Backports commit 39ae2474e337247e5930e8be783b689adc9f6215 from qemu
All the places in armv7m_cpu_do_interrupt() which pend an
exception in the NVIC are doing so for synchronous
exceptions. We know that we will always take some
exception in this case, so we can just acknowledge it
immediately, rather than returning and then immediately
being called again because the NVIC has raised its outbound
IRQ line.
Backports commit a25dc805e2e63a55029e787a52335e12dabf07dc from qemu
The M profile condition for when we can take a pending exception or
interrupt is not the same as that for A/R profile. The code
originally copied from the A/R profile version of the
cpu_exec_interrupt function only worked by chance for the
very simple case of exceptions being masked by PRIMASK.
Replace it with a call to a function in the NVIC code that
correctly compares the priority of the pending exception
against the current execution priority of the CPU.
Backports commit 7ecdaa4a9635f1ded0dfa9218c25273b6d4dcd44 from qemu
Having armv7m_nvic_acknowledge_irq() return the new value of
env->v7m.exception and its one caller assign the return value
back to env->v7m.exception is pointless. Just make the return
type void instead.
Backports commit a5d8235545e98c1ce02560d5f4f57552d937efe9 from qemu
Implement HFNMIENA support for the M profile MPU. This bit controls
whether the MPU is treated as enabled when executing at execution
priorities of less than zero (in NMI, HardFault or with the FAULTMASK
bit set).
Doing this requires us to use a different MMU index for "running
at execution priority < 0", because we will have different
access permissions for that case versus the normal case.
Backports commit 3bef7012560a7f0ea27b265105de5090ba117514 from qemu
The M series MPU is almost the same as the already implemented R
profile MPU (v7 PMSA). So all we need to implement here is the MPU
register interface in the system register space.
This implementation has the same restriction as the R profile MPU
that it doesn't permit regions to be sized down smaller than 1K.
We also do not yet implement support for MPU_CTRL.HFNMIENA; this
bit should if zero disable use of the MPU when running HardFault,
NMI or with FAULTMASK set to 1 (ie at an execution priority of
less than zero) -- if the MPU is enabled we don't treat these
cases any differently.
Backports commit 29c483a506070e8f554c77d22686f405e30b9114 from qemu
General logic is that operations stopped by the MPU are MemManage,
and those which go through the MPU and are caught by the unassigned
handle are BusFault. Distinguish these by looking at the
exception.fsr values, and set the CFSR bits and (if appropriate)
fill in the BFAR or MMFAR with the exception address.
Backports commit 5dd0641d234e355597be62e5279d8a519c831625 from qemu
All M profile CPUs are PMSA, so set the feature bit.
(We haven't actually implemented the M profile MPU register
interface yet, but setting this feature bit gives us closer
to correct behaviour for the MPU-disabled case.)
Backports commit 790a11503cfb5e1dcd031ea2212bbebae4ca3cec from qemu
Add support for the M profile default memory map which is used
if the MPU is not present or disabled.
The main differences in behaviour from implementing this
correctly are that we set the PAGE_EXEC attribute on
the right regions of memory, such that device regions
are not executable.
Backports commit 3a00d560bcfca7ad04327062c1986a016c104b1f from qemu
Improve the "-d mmu" tracing for the PMSAv7 MPU translation
process as an aid in debugging guest MPU configurations:
* fix a missing newline for a guest-error log
* report the region number with guest-error or unimp
logs of bad region register values
* add a log message for the overall result of the lookup
* print "0x" prefix for hex values
Backports commit c9f9f1246d630960bce45881e9c0d27b55be71e2 from qemu
Now that we enforce both:
* pmsav7_dregion == 0 implies has_mpu == false
* PMSA with has_mpu == false means SCTLR.M cannot be set
we can remove a check on pmsav7_dregion from get_phys_addr_pmsav7(),
because we can only reach this code path if the MPU is enabled
(and so region_translation_disabled() returned false).
Backports commit e9235c6983b261e04e897e8ff900b2b7a391e644 from qemu
If the CPU is a PMSA config with no MPU implemented, then the
SCTLR.M bit should be RAZ/WI, so that the guest can never
turn on the non-existent MPU.
Backports commit 06312febfb2d35367006ef23608ddd6a131214d4 from qemu
Fix the handling of QOM properties for PMSA CPUs with no MPU:
Allow no-MPU to be specified by either:
* has-mpu = false
* pmsav7_dregion = 0
and make setting one imply the other. Don't clear the PMSA
feature bit in this situation.
Backports commit f50cd31413d8bc9d1eef8edd1f878324543bf65d from qemu
ARM CPUs come in two flavours:
* proper MMU ("VMSA")
* only an MPU ("PMSA")
For PMSA, the MPU may be implemented, or not (in which case there
is default "always acts the same" behaviour, but it isn't guest
programmable).
QEMU is a bit confused about how we indicate this: we have an
ARM_FEATURE_MPU, but it's not clear whether this indicates
"PMSA, not VMSA" or "PMSA and MPU present" , and sometimes we
use it for one purpose and sometimes the other.
Currently trying to implement a PMSA-without-MPU core won't
work correctly because we turn off the ARM_FEATURE_MPU bit
and then a lot of things which should still exist get
turned off too.
As the first step in cleaning this up, rename the feature
bit to ARM_FEATURE_PMSA, which indicates a PMSA CPU (with
or without MPU).
Backports commit 452a095526a0537f16c271516a2200877a272ea8 from qemu
Make M profile use completely separate ARMMMUIdx values from
those that A profile CPUs use. This is a prelude to adding
support for the MPU and for v8M, which together will require
6 MMU indexes which don't map cleanly onto the A profile
uses:
non secure User
non secure Privileged
non secure Privileged, execution priority < 0
secure User
secure Privileged
secure Privileged, execution priority < 0
Backports commit e7b921c2d9efc249f99b9feb0e7dca82c96aa5c4 from qemu
The v7M exception architecture requires that if a synchronous
exception cannot be taken immediately (because it is disabled
or at too low a priority) then it should be escalated to
HardFault (and the HardFault exception is then taken).
Implement this escalation logic.
Backports commit a73c98e159d18155445d29b6044be6ad49fd802f from qemu
The M profile CPU's MPU has an awkward corner case which we
would like to implement with a different MMU index.
We can avoid having to bump the number of MMU modes ARM
uses, because some of our existing MMU indexes are only
used by non-M-profile CPUs, so we can borrow one.
To avoid that getting too confusing, clean up the code
to try to keep the two meanings of the index separate.
Instead of ARMMMUIdx enum values being identical to core QEMU
MMU index values, they are now the core index values with some
high bits set. Any particular CPU always uses the same high
bits (so eventually A profile cores and M profile cores will
use different bits). New functions arm_to_core_mmu_idx()
and core_to_arm_mmu_idx() convert between the two.
In general core index values are stored in 'int' types, and
ARM values are stored in ARMMMUIdx types.
Backports commit 8bd5c82030b2cb09d3eef6b444f1620911cc9fc5 from qemu
The PMUv3 driver of linux kernel (in arch/arm64/kernel/perf_event.c)
relies on the PMUVER field of id_aa64dfr0_el1 to decide if PMU support
is present or not. This patch clears the PMUVER field under TCG mode
when vPMU=off. Without it, PMUv3 will init insider guest VMs even
with vPMU=off. This patch also removes a redundant line inside the
if-statement.
Backports commit 2b3ffa929249b15a75d8bde3e8e57a744f52aff0 from qemu
When identifying the DFSR format for an alignment fault, use
the mmu index that we are passed, rather than calling cpu_mmu_index()
to get the mmu index for the current CPU state. This doesn't actually
make any difference since the only cases where the current MMU index
differs from the index used for the load are the "unprivileged
load/store" instructions, and in that case the mmu index may
differ but the translation regime is the same (apart from the
"use from Hyp mode" case which is UNPREDICTABLE).
However it's the more logical thing to do.
Backports commit e517d95b63427fae9f03958dbc005c36b4ebf2cf from qemu
Now that we've rewritten M-profile exception return so that the magic
PC values are not visible to other parts of QEMU, we can delete the
special casing of them elsewhere.
Backports commit f4e8e4edda875cab9df91dc4ae9767f7cb1f50aa from qemu
On M profile, return from exceptions happen when code in Handler mode
executes one of the following function call return instructions:
* POP or LDM which loads the PC
* LDR to PC
* BX register
and the new PC value is 0xFFxxxxxx.
QEMU tries to implement this by not treating the instruction
specially but then catching the attempt to execute from the magic
address value. This is not ideal, because:
* there are guest visible differences from the architecturally
specified behaviour (for instance jumping to 0xFFxxxxxx via a
different instruction should not cause an exception return but it
will in the QEMU implementation)
* we have to account for it in various places (like refusing to take
an interrupt if the PC is at a magic value, and making sure that
the MPU doesn't deny execution at the magic value addresses)
Drop these hacks, and instead implement exception return the way the
architecture specifies -- by having the relevant instructions check
for the magic value and raise the 'do an exception return' QEMU
internal exception immediately.
The effect on the generated code is minor:
bx lr, old code (and new code for Thread mode):
TCG:
mov_i32 tmp5,r14
movi_i32 tmp6,$0xfffffffffffffffe
and_i32 pc,tmp5,tmp6
movi_i32 tmp6,$0x1
and_i32 tmp5,tmp5,tmp6
st_i32 tmp5,env,$0x218
exit_tb $0x0
set_label $L0
exit_tb $0x7f2aabd61993
x86_64 generated code:
0x7f2aabe87019: mov %ebx,%ebp
0x7f2aabe8701b: and $0xfffffffffffffffe,%ebp
0x7f2aabe8701e: mov %ebp,0x3c(%r14)
0x7f2aabe87022: and $0x1,%ebx
0x7f2aabe87025: mov %ebx,0x218(%r14)
0x7f2aabe8702c: xor %eax,%eax
0x7f2aabe8702e: jmpq 0x7f2aabe7c016
bx lr, new code when in Handler mode:
TCG:
mov_i32 tmp5,r14
movi_i32 tmp6,$0xfffffffffffffffe
and_i32 pc,tmp5,tmp6
movi_i32 tmp6,$0x1
and_i32 tmp5,tmp5,tmp6
st_i32 tmp5,env,$0x218
movi_i32 tmp5,$0xffffffffff000000
brcond_i32 pc,tmp5,geu,$L1
exit_tb $0x0
set_label $L1
movi_i32 tmp5,$0x8
call exception_internal,$0x0,$0,env,tmp5
x86_64 generated code:
0x7fe8fa1264e3: mov %ebp,%ebx
0x7fe8fa1264e5: and $0xfffffffffffffffe,%ebx
0x7fe8fa1264e8: mov %ebx,0x3c(%r14)
0x7fe8fa1264ec: and $0x1,%ebp
0x7fe8fa1264ef: mov %ebp,0x218(%r14)
0x7fe8fa1264f6: cmp $0xff000000,%ebx
0x7fe8fa1264fc: jae 0x7fe8fa126509
0x7fe8fa126502: xor %eax,%eax
0x7fe8fa126504: jmpq 0x7fe8fa122016
0x7fe8fa126509: mov %r14,%rdi
0x7fe8fa12650c: mov $0x8,%esi
0x7fe8fa126511: mov $0x56095dbeccf5,%r10
0x7fe8fa12651b: callq *%r10
which is a difference of one cmp/branch-not-taken. This will
be lost in the noise of having to exit generated code and
look up the next TB anyway.
Backports commit 3bb8a96f5348913ee130169504f3642f501b113e from qemu
For M profile exception-return handling we'd like to generate different
code for some instructions depending on whether we are in Handler
mode or Thread mode. This isn't the same as "are we privileged
or user", so we need an extra bit in the TB flags to distinguish.
Backports commit 064c379c99b835bdcc478d21a3849507ea07d53a from qemu
Move the code to generate the "condition failed" instruction
codepath out of the if (singlestepping) {} else {}. This
will allow adding support for handling a new is_jmp type
which can't be neatly split into "singlestepping case"
versus "not singlestepping case".
Backports commit f021b2c4627890d82fbcc300db3bd782b37b7f8a from qemu
arm: Abstract out "are we singlestepping" test to utility function
We now test for "are we singlestepping" in several places and
it's not a trivial check because we need to care about both
architectural singlestep and QEMU gdbstub singlestep. We're
also about to add another place that needs to make this check,
so pull the condition out into a function.
Backports commit b636649f5a2e108413dd171edaf320f781f57942 from qemu
Move the utility routines gen_set_condexec() and gen_set_pc_im()
up in the file, as we will want to use them from a function
placed earlier in the file than their current location.
Backports commit 4d5e8c969a74c86124fc2284ea603cc6dd3c5dfa from qemu
We currently have two places that do:
if (dc->ss_active) {
gen_step_complete_exception(dc);
} else {
gen_exception_internal(EXCP_DEBUG);
}
Factor this out into its own function, as we're about to add
a third place that needs the same logic.
Backports commit 5425415ebba5fa20558e1ef25e1997a6f5ea4c7c from qemu
In Thumb mode, the only instructions which can cause an interworking
branch by writing the PC are BLX, BX, BXJ, LDR, POP and LDM. Unlike
ARM mode, data processing instructions which target the PC do not
cause interworking branches.
When we added support for doing interworking branches on writes to
PC from data processing instructions in commit 21aeb3430ce7ba, we
accidentally changed a Thumb instruction to have interworking
branch behaviour for writes to PC. (MOV, MOVS register-shifted
register, encoding T2; this is the standard encoding for
LSL/LSR/ASR/ROR (register).)
For this encoding, behaviour with Rd == R15 is specified as
UNPREDICTABLE, so allowing an interworking branch is within
spec, but it's confusing and differs from our handling of this
class of UNPREDICTABLE for other Thumb ALU operations. Make
it perform a simple (non-interworking) branch like the others.
Backports commit bedb8a6b09c1754c3b9f155750c62dc087706698 from qemu
For M-profile CPUs, the BXJ instruction does not exist at all, and
the encoding should always UNDEF. We were accidentally implementing
it to behave like A-profile BXJ; correct the error.
Backports commit 9d7c59c84d4530d05e8702b1c3a31e6da00a397e from qemu
In tlb_fill() we construct a syndrome register value from a
fault status register value which is filled in by arm_tlb_fill().
arm_tlb_fill() returns FSR values which might be in the format
used with short-format page descriptors, or the format used
with long-format (LPAE) descriptors. The syndrome register
always uses LPAE-format FSR status codes.
It isn't actually possible to end up delivering a syndrome
register value to the guest for a fault which is reported
with a short-format FSR (that kind of stage 1 fault will only
happen for an AArch32 translation regime which doesn't have
a syndrome register, and can never be redirected to an AArch64
or Hyp exception level). Add an assertion which checks this,
and adjust the code so that we construct a syndrome with
an invalid status code, rather than allowing set bits in
the FSR input to randomly corrupt other fields in the syndrome.
Backports commit 65ed2ed90d9d81fd4b639029be850ea5651f919f from qemu
The excnames[] array is defined in internals.h because we used
to use it from two different source files for handling logging
of AArch32 and AArch64 exception entry. Refactoring means that
it's now used only in arm_log_exception() in helper.c, so move
the array into that function.
Backports commit 2c4a7cc5afb1bfc1728a39abd951ddd7714c476e from qemu
Recent changes have added new EXCP_ values to ARM but forgot
to update the excnames[] array which is used to provide
human-readable strings when printing information about the
exception for debug logging. Add the missing entries, and
add a comment to the list of #defines to help avoid the mistake
being repeated in future.
Backports commit 32b81e620ea562d56ab2733421b5da1082b237a2 from qemu
For "ldp x0, x1, [x0]", if the second load is on a second page and
the second page is unmapped, the exception would be raised with x0
already modified. This means the instruction couldn't be restarted.
Backports commit 2d1bbf51c2cb948da4b6fd5f91cf3ecc80b28156 from qemu
The existing code for "host" and "max" CPU models overrides every
single feature in the CPU object at realize time, even the ones
that were explicitly enabled or disabled by the user using
"feat=on" or "feat=off", while features set using +feat/-feat are
kept.
This means "-cpu host,+invtsc" works as expected, while
"-cpu host,invtsc=on" doesn't.
This was a known bug, already documented in a comment inside
x86_cpu_expand_features(). What makes this bug worse now is that
libvirt 3.0.0 and newer now use "feat=on|off" instead of
+feat/-feat when it detects a QEMU version that supports it (see
libvirt commit d47db7b16dd5422c7e487c8c8ee5b181a2f9cd66).
Change the feature property getter/setter to set a
env->user_features field, to keep track of features that were
explicitly changed using QOM properties. Then make the
max_features code not override user features when handling "-cpu
host" and "-cpu max".
This will also allow us to remove the plus_features/minus_features
hack in the future, but I plan to do that after 2.9.0 is
released.
Backports commit d4a606b38b5d4b3689b86cc1575908e82179ecfb from qemu
It is unnecessary to test R6 from delay/forbidden slot check
in gen_msa_branch().
https://bugs.launchpad.net/qemu/+bug/1663287
Backports commit 075a1fe788d36b271ec25507466c30b9a90b5d54 from qemu
this fixes many warnings like:
target/mips/translate.c:6253:13: warning: Value stored to 'rn' is never read
rn = "invalid sel";
^ ~~~~~~~~~~~~~
Backports commit 3570d7f6672836140f0a1ec9bf95dd5ea50a2aaa from qemu
static code analyzer complain:
target/mips/helper.c:453:5: warning: Function call argument is an uninitialized value
qemu_log_mask(CPU_LOG_MMU,
^~~~~~~~~~~~~~~~~~~~~~~~~~
'physical' and 'prot' are uninitialized if 'ret' is not TLBRET_MATCH.
Backports commit def74c0cf05722b2e502d4b4f1219966c5b0cbd3 from qemu
Our implementation of writes to the APSR for M-profile via the MSR
instruction was badly broken.
First and worst, we had the sense wrong on the test of bit 2 of the
SYSm field -- this is supposed to request an APSR write if bit 2 is 0
but we were doing it if bit 2 was 1. This bug was introduced in
commit 58117c9bb429cd, so hasn't been in a QEMU release.
Secondly, the choice of exactly which parts of APSR should be written
is defined by bits in the 'mask' field. We were not passing these
through from instruction decode, making it impossible to check them
in the helper.
Pass the mask bits through from the instruction decode to the helper
function and process them appropriately; fix the wrong sense of the
SYSm bit 2 check.
Invalid mask values and invalid combinations of mask and register
number are UNPREDICTABLE; we choose to treat them as if the mask
values were valid.
Backports commit b28b3377d7e9ba35611d454d5a63ef50cab1f8c5 from qemu
For M profile (unlike A profile) the reset value of R14 is specified
as 0xffffffff. (The rationale is that this is an illegal exception
return value, so if guest code tries to return to it it will result
in a helpful exception.)
Registers r0 to r12 and the flags are architecturally UNKNOWN on
reset, so we leave those at zero.
Backports commit 056f43df9168413f304500b69c33158d66efb7cf from qemu
For M profile CPUs, FAULTMASK should be 0 on reset, like PRIMASK.
QEMU stores FAULTMASK in the PSTATE F bit, so (as with PRIMASK in the
I bit) we have to clear these to undo the A profile default of 1.
Update the comment accordingly and move it so that it's closer to the
code it's referring to.
Backports commit dc7abe4d65ad39390b2db120f5ad18f8f6576f8b from qemu
For v7M attempts to access a nonexistent coprocessor are reported
differently from plain undefined instructions (as UsageFaults of type
NOCP rather than type UNDEFINSTR). Split them out into a new
EXCP_NOCP so we can report the FSR value correctly.
Backports commit 7517748e3f71a3099e57915fba95c4c308e6d842 from qemu
For v7M attempts to access a nonexistent coprocessor are reported
differently from plain undefined instructions (as UsageFaults of type
NOCP rather than type UNDEFINSTR). Split them out into a new
EXCP_NOCP so we can report the FSR value correctly.
Backports commit 7517748e3f71a3099e57915fba95c4c308e6d842 from qemu
When we take an exception for an undefined instruction, set the
appropriate CFSR bit.
Backports commit 81dd9648c69bb89afdd6f4bb3ed6f3efdac96524 from qemu
The CCR.STACKALIGN bit controls whether the CPU is supposed to force
8-alignment of the stack pointer on entry to the exception handler.
Backports commit dc858c6633a9af8b80c1509cf6f825e4390d3ad1 from qemu
Add the structure fields, VMState fields, reset code and macros for
the v7M system control registers CCR, CFSR, HFSR, DFSR, MMFAR and
BFAR.
Backports commit 2c4da50d9477fb830d778bb5d6a11215aa359b44 from qemu
Give an explicit error and abort when a load
from the vector table fails. Architecturally this
should HardFault (which will then immediately
fail to load the HardFault vector and go into Lockup).
Since we don't model Lockup, just report this guest
error via cpu_abort(). This is more helpful than the
previous behaviour of reading a zero, which is the
address of the reset stack pointer and not a sensible
location to jump to.
Backports commit 1b9ea408fca1ce8caae67b792355b023c69c5ac5 from qemu
For v7m we need to catch attempts to execute from special
addresses at 0xfffffff0 and above. Previously we did this
with the aid of a hacky special purpose lump of memory
in the address space and a check in translate.c for whether
we were translating code at those addresses.
We can implement this more cleanly using a CPU
unassigned access handler which throws the exception
if the unassigned access is for one of the special addresses.
Backports commit 542b3478a00cb7ef51c259255b3ab1e2a7daada2 from qemu
The MRS and MSR instruction handling has a number of flaws:
* unprivileged accesses should only be able to read
CONTROL and the xPSR subfields, and only write APSR
(others RAZ/WI)
* privileged access should not be able to write xPSR
subfields other than APSR
* accesses to unimplemented registers should log as
guest errors, not abort QEMU
Backports commit 58117c9bb429cd9552d998687aa99088eb1d8528 from qemu
The v7m CONTROL register bit 1 is SPSEL, which indicates
the stack being used. We were storing this information
not in v7m.control but in the separate v7m.other_sp
structure field. Unfortunately, the code handling reads
of the CONTROL register didn't take account of this, and
so if SPSEL was updated by an exception entry or exit then
a subsequent guest read of CONTROL would get the wrong value.
Using a separate structure field doesn't really gain us
anything in efficiency, so drop this unnecessary complexity
in favour of simply storing all the bits in v7m.control.
This is a migration compatibility break for M profile
CPUs only.
Backports commit abc24d86cc0364f402e438fae3acb14289b40734 from qemu
The MRS instruction requires that bits [19..16] are all 1s, and for
A/R profile also that bits [7..0] are all 0s. At this point in the
decode tree we have checked all of the rest of the instruction but
were allowing these to be any value. If these bits are not set then
the result is architecturally UNPREDICTABLE, but choosing to UNDEF is
more helpful to the user and avoids unexpected odd behaviour if the
encodings are used for some purpose in future architecture versions.
Backports commit 3d54026fb06d1aea7ebb4e9825970b06bebcacac from qemu
M profile doesn't have the MSR(banked) and MRS(banked) instructions
and uses the encodings for different kinds of M-profile MRS/MSR.
Guard the relevant bits of the decode logic to make sure we don't
accidentally fall into them by accident on M-profile.
(The bit being checked for this (bit 5) is part of the SYSm field on
M-profile, but since no currently allocated system registers have
encodings with bit 5 of SYSm set, this hasn't been a problem in
practice.)
Backports commit 43ac65742319ef5ac4461daf43316b189cd21e89 from qemu
M profile doesn't have the HVC or SMC encodings, so make them always
UNDEF rather than generating calls to helper functions that assume
A/R profile.
Backports commit 001b3cab51ebfcb13e8dd03ea25bfa3bd0c517a3 from qemu
The power state spec section 5.1.5 AFFINITY_INFO defines the
affinity info return values as
0 ON
1 OFF
2 ON_PENDING
I grepped QEMU for power_state to ensure that no assumptions
of OFF=0 were being made.
Backports commit d5affb0d8677e1a8a8fe03fa25005b669e7cdc02 from qemu
In armv8, this register implements more than a single bit, with
fine-grained enables for read access to event counters, cycles
counters, and write access to the software increment. This change
implements those checks using custom access functions for the relevant
registers.
Backports commit 6ecd0b6ba0591ef280ed984103924d4bdca5ac32 from qemu
glibc blacklists TSX on Haswell CPUs with model==60 and
stepping < 4. To make the Haswell CPU model more useful, make
those guests actually use TSX by changing CPU stepping to 4.
References:
* glibc commit 2702856bf45c82cf8e69f2064f5aa15c0ceb6359
https://sourceware.org/git/?p=glibc.git;a=commit;h=2702856bf45c82cf8e69f2064f5aa15c0ceb6359
Backports commit ec56a4a7b07e2943f49da273a31e3195083b1f2e from qemu
Helper function for code that needs to check the host CPU
vendor/family/model/stepping values.
Backports commit 20271d484069f154fb262507e63adc3a37e885d2 from qemu
..just like the rest of the displayed ESR register. Otherwise people
might scratch their heads if a not obviously hex number is displayed
for the EC field.
Backports commit 6568da459b611845ef55526cd23afc9fa9f4647f from qemu
Paths through the softmmu code during code generation now need to be audited
to check for double locking of tb_lock. In particular, VMEXIT can take tb_lock
through cpu_vmexit -> cpu_x86_update_cr4 -> tlb_flush.
To avoid this, split VMEXIT delivery in two parts, similar to what is done with
exceptions. cpu_vmexit only records the VMEXIT exit code and information, and
cc->do_interrupt can then deliver it when it is safe to take the lock.
Backports commit 10cde894b63146139f981857e4eedf756fa53dcb from qemu
This suppresses the incorrect warning when forcing MTTCG for x86
guests on x86 hosts. A future patch will still warn when
TARGET_SUPPORT_MTTCG hasn't been defined for the guest (which is still
pending for x86).
Backports commit 72c1701f62e8d44eb24a0583a958edc280105455 from qemu
CPU runnability checks and CPU model expansion have slightly
different requirements. Document the steps involved in loading a
CPU model and realizing a CPU, so their requirements and purpose
are clearly defined.
This patch doesn't change any implementation. It just add
comments, rename the x86_cpu_load_features() function for clarity
(so it won't be confused with x86_cpu_load_def()), and move
x86_cpu_filter_features() closer to it.
Backports commit b8d834a00fa3ed4dad7d371e1a00938a126a54a0 from qemu
The aarch64 crypto instructions for AES and SHA are missing the
check for if the FPU is enabled.
Backports commit a4f5c5b72380deeccd53a6890ea3782f10ca8054 from qemu
This enables the multi-threaded system emulation by default for ARMv7
and ARMv8 guests using the x86_64 TCG backend. This is because on the
guest side:
- The ARM translate.c/translate-64.c have been converted to
- use MTTCG safe atomic primitives
- emit the appropriate barrier ops
- The ARM machine has been updated to
- hold the BQL when modifying shared cross-vCPU state
- defer powerctl changes to async safe work
All the host backends support the barrier and atomic primitives but
need to provide same-or-better support for normal load/store
operations.
Backports commit ca759f9e387db87e1719911f019bc60c74be9ed8 from qemu
The WFE and YIELD instructions are really only hints and in TCG's case
they were useful to move the scheduling on from one vCPU to the next. In
the parallel context (MTTCG) this just causes an unnecessary cpu_exit
and contention of the BQL.
Backports commit c22edfebff29f63d793032e4fbd42a035bb73e27 from qemu
While the vargs approach was flexible the original MTTCG ended up
having munge the bits to a bitmap so the data could be used in
deferred work helpers. Instead of hiding that in cputlb we push the
change to the API to make it take a bitmap of MMU indexes instead.
For ARM some the resulting flushes end up being quite long so to aid
readability I've tended to move the index shifting to a new line so
all the bits being or-ed together line up nicely, for example:
tlb_flush_page_by_mmuidx(other_cs, pageaddr,
(1 << ARMMMUIdx_S1SE1) |
(1 << ARMMMUIdx_S1SE0));
Backports commit 0336cbf8532935d8e23c2aabf3e2ce2c0697b6ac from qemu
This makes qemu_strtosz(), qemu_strtosz_mebi() and
qemu_strtosz_metric() similar to qemu_strtoi64(), except negative
values are rejected.
Backports commit f17fd4fdf0df3d2f3444399d04c38d22b9a3e1b7 from qemu
Change the qemu_strtosz() & friends to return -EINVAL when @endptr is
null and the conversion doesn't consume the string completely.
Matches how qemu_strtol() & friends work.
Only test_qemu_strtosz_simple() passes a null @endptr. No functional
change there, because its conversion consumes the string.
Simplify callers that use @endptr only to fail when it doesn't point
to '\0' to pass a null @endptr instead.
Backports commit 4fcdf65ae2c00ae69f7625f26ed41f37d77b403c from qemu
To parse numbers with metric suffixes, we use
qemu_strtosz_suffix_unit(nptr, &eptr, QEMU_STRTOSZ_DEFSUFFIX_B, 1000)
Capture this in a new function for legibility:
qemu_strtosz_metric(nptr, &eptr)
Replace test_qemu_strtosz_suffix_unit() by test_qemu_strtosz_metric().
Rename qemu_strtosz_suffix_unit() to do_strtosz() and give it internal
linkage.
Backports commit d2734d2629266006b0413433778474d5801c60be from qemu
Provide a new cpu_supports_isa function which allows callers to
determine whether a CPU supports one of the ISA_ flags, by testing
whether the associated struct mips_def_t sets the ISA flags in its
insn_flags field.
An example use of this is to allow boards which generate bootloader code
to determine the properties of the CPU that will be used, for example
whether the CPU is 64 bit or which architecture revision it implements.
Backports commit bed9e5ceb158c886d548fe59675a6eba18baeaeb from qemu
This patch contains several fixes to enable vPMU under TCG mode. It
first removes the checking of kvm_enabled() while unsetting
ARM_FEATURE_PMU. With it, the .pmu option can be used to turn on/off vPMU
under TCG mode. Secondly the PMU node of DT table is now created under TCG.
The last fix is to disable the masking of PMUver field of ID_AA64DFR0_EL1.
Backports commit d6f02ce3b8a43ddd8f83553fe754a34b26fb273f from qemu
In order to support Linux perf, which uses PMXEVTYPER register,
this patch adds read/write access support for PMXEVTYPER. The access
is CONSTRAINED UNPREDICTABLE when PMSELR is not 0x1f. Additionally
this patch adds support for PMXEVTYPER_EL0.
Backports commit fdb8665672ded05f650d18f8b62d5c8524b4385b from qemu
This patch adds support for AArch64 register PMSELR_EL0. The existing
PMSELR definition is revised accordingly.
Backports commit 6b0407805d46bbeba70f4be426285d0a0e669750 from qemu
Add support for generating the ISS (Instruction Specific Syndrome)
for Data Abort exceptions taken from AArch32. These syndromes are
used by hypervisors for example to trap and emulate memory accesses.
This is the equivalent for AArch32 guests of the work done for AArch64
guests in commit aaa1f954d4cab243.
Backports commit 9bb6558a218bf7e466e5ac1100639517d8a30d33 from qemu
In the ARM ldr/str decode path, rather than directly testing
"insn & (1 << 21)" and "insn & (1 << 24)", abstract these
bits out into wbit and pbit local flags. (We will want to
do more tests against them to determine whether we need to
provide syndrome information.)
Backports commit 63f26fcfda8e19f94ce23336726d14805250a5b6 from qemu
In BE32 mode, sub-word size watchpoints can fail to trigger because the
address of the access is adjusted in the opcode helpers before being
compared with the watchpoint registers. This patch reverses the address
adjustment before performing the comparison with the help of a new CPUClass
hook.
This version of the patch augments and tidies up comments a little.
Backports commit 40612000599e52e792d23c998377a0fa429c4036 from qemu
Thumb-1 code has some issues in BE32 mode (as currently implemented). In
short, since bytes are swapped within words at load time for BE32
executables, this also swaps pairs of adjacent Thumb-1 instructions.
This patch un-swaps those pairs of instructions again, both for execution,
and for disassembly. (The previous version of the patch always read four
bytes in arm_read_memory_func and then extracted the proper two bytes,
in a probably misguided attempt to match the behaviour of actual hardware
as described by e.g. the ARM9TDMI TRM, section 3.3 "Endian effects for
instruction fetches". It's less complicated to just read the correct
two bytes though.)
Backports commit f7478a92dd9ee2276bfaa5b7317140d3f9d6a53b from qemu
Add a new "cfgend" property which selects whether the CPU resets into
big-endian mode or not. This setting affects whether we reset with
SCTLR_B (ARMv6 and earlier) or SCTLR_EE (ARMv7 and later) set.
Backports commit 3a062d5730266b2386eeda68b1a1c6e96451db31 from qemu
stub version of MISMATCH_CHECK is empty so it's easy to misuse for
people not building kvm on arm. Use QEMU_BUILD_BUG_ON similar to the
non-stub version to make it easier to catch bugs.
Backports commit 705ae59fecae341a4b1a45ce48b46de4b1bb3cf4 from qemu
Macro calls without a trailing ; look weird in C, this works as a side
effect of how QEMU_BUILD_BUG_ON is implemented. Fix this up.
Backports commit 1b28762a333bd238611103e9ed2348d7af93b0db from qemu
We only use the IS_M() macro in two places, and it's a bit of a
namespace grab to put in cpu.h. Drop it in favour of just explicitly
calling arm_feature() in the places where it was used.
Backports commit 531c60a97ab51618b4b9ccef1c5fe00607079706 from qemu
When CPU vendor is set to AMD, the AMD feature alias bits on
CPUID[0x80000001].EDX are already automatically copied from CPUID[1].EDX
on x86_cpu_realizefn(). When CPU vendor is Intel, those bits are
reserved and should be zero. On either case, those bits shouldn't be set
in the CPU model table.
Commit 726a8ff68677d8d5fba17eb0ffb85076bfb598dc removed those
bits from most CPU models, but the Opteron_* entries still have
them. Remove the alias bits from Opteron_* too.
Add an assert() to x86_register_cpudef_type() to ensure we don't
make the same mistake again.
Backports commit 2a923a293df95334fa22634016efdd138f49da7f from qemu
AVX512_VPOPCNTDQ: Vector POPCNT instructions for word and qwords.
variable precision.
Backports commit f77543772dcd38fa438470d9b80bafbd3a3ebbd7 from qemu
Enable the ARM_FEATURE_EL2 bit on Cortex-A52 and
Cortex-A57, since this is all now sufficiently implemented
to work with the GICv3. We provide the usual CPU property
to disable it for backwards compatibility with the older
virt boards.
In this commit, we disable the EL2 feature on the
virt and ZynpMP boards, so there is no overall effect.
Another commit will expose a board-level property to
allow the user to enable EL2.
Backports commit c25bd18a04c8bd0f19556d719864b7b08528222d from qemu
The PSCI spec states that a CPU_ON call should cause the new
CPU to be started in the highest implemented Non-secure
exception level. We were incorrectly starting it at the
exception level of the caller, which happens to be correct
if EL2 is not implemented. Implement the correct logic
as described in the PSCI 1.0 spec section 6.4:
* if EL2 exists and SCR_EL3.HCE is set: start in EL2
* otherwise start in EL1
Backports commit 3f591a20221511c639cc7959755e570801a21cd2 from qemu
Split ARM on/off function from PSCI support code.
This will allow to reuse these functions in other code.
Backports commit 825482adde1f971cbddf27e15fb4453ab3fae994 from qemu
The DBGVCR_EL2 system register is needed to run a 32-bit
EL1 guest under a Linux EL2 64-bit hypervisor. Its only
purpose is to provide AArch64 with access to the state of
the DBGVCR AArch32 register. Since we only have a dummy
DBGVCR, implement a corresponding dummy DBGVCR32_EL2.
Backports commit 4d2ec4da1c2d60c9fd8bad137506870c2f980410 from qemu
To run a VM in 32-bit EL1 our AArch32 interrupt handling code
needs to be able to cope with VIRQ and VFIQ exceptions.
These behave like IRQ and FIQ except that we don't need to try
to route them to Monitor mode.
Backports commit 87a4b270348c69a446ebcddc039bfae31b1675cb from qemu
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Backports commit fcf5ef2ab52c621a4617ebbef36bf43b4003f4c0 from qemu
