HCR_EL2.TID3 mandates that access from EL1 to a long list of id
registers traps to EL2, and QEMU has so far ignored this requirement.
This breaks (among other things) KVM guests that have PtrAuth enabled,
while the hypervisor doesn't want to expose the feature to its guest.
To achieve this, KVM traps the ID registers (ID_AA64ISAR1_EL1 in this
case), and masks out the unsupported feature.
QEMU not honoring the trap request means that the guest observes
that the feature is present in the HW, starts using it, and dies
a horrible death when KVM injects an UNDEF, because the feature
*really* isn't supported.
Do the right thing by trapping to EL2 if HCR_EL2.TID3 is set.
Note that this change does not include trapping of the MVFR
registers from AArch32 (they are accessed via the VMRS
instruction and need to be handled in a different way).
Backports commit 6a4ef4e5d1084ce41fafa7d470a644b0fd3d9317 from qemu
The ARMv8 ARM states when executing at EL2, EL3 or Secure EL1,
ISR_EL1 shows the pending status of the physical IRQ, FIQ, or
SError interrupts.
Unfortunately, QEMU's implementation only considers the HCR_EL2
bits, and ignores the current exception level. This means a hypervisor
trying to look at its own interrupt state actually sees the guest
state, which is unexpected and breaks KVM as of Linux 5.3.
Instead, check for the running EL and return the physical bits
if not running in a virtualized context.
Backports commit 7cf95aed53c8770a338617ef40d5f37d2c197853 from qemu
According to the PushStack() pseudocode in the armv7m RM,
bit 4 of the LR should be set to NOT(CONTROL.PFCA) when
an FPU is present. Current implementation is doing it for
armv8, but not for armv7. This patch makes the existing
logic applicable to both code paths.
Backports commit f900b1e5b087a02199fbb6de7038828008e9e419 from qemu
Simply moving the non-stub helper_v7m_mrs/msr outside of
!CONFIG_USER_ONLY is not an option, because of all of the
other system-mode helpers that are called.
But we can split out a few subroutines to handle the few
EL0 accessible registers without duplicating code.
Backports commit 04c9c81b8fa2ee33f59a26265700fae6fc646062 from qemu
There was too much cut and paste between ldrexd and strexd,
as ldrexd does prohibit two output registers the same.
Fixes: af288228995
Backports commit 655b02646dc175dc10666459b0a1e4346fc8d46a from qemu
Preparation for collapsing the two byte swaps, adjust_endianness and
handle_bswap, along the I/O path.
Target dependant attributes are conditionalized upon NEED_CPU_H.
Backports commit 14776ab5a12972ea439c7fb2203a4c15a09094b4 from qemu
Switch the SPARC target from the old unassigned_access hook to the
new do_transaction_failed hook.
This will cause the "if transaction failed" code paths added in
the previous commits to become active if the access is to an
unassigned address. In particular we'll now handle bus errors
during page table walks correctly (generating a translation
error with the right kind of fault status).
Backports commit f8c3db33a5e863291182f8862ddf81618a7c6194 from qemu
The dump_mmu() function does a ldl_phys() at the start, but
then never uses the value it loads at all. Remove the
unused code.
Backports commit 9dffeec2e003a482ca858a887d3454c6bebed91e from qemu
Convert the mmu_probe() function to using address_space_ldl()
rather than ldl_phys(), so we can explicitly detect memory
transaction failures.
This makes no practical difference at the moment, because
ldl_phys() will return 0 on a transaction failure, and we
treat transaction failures and 0 PDEs identically. However
the spec says that MMU probe operations are supposed to
update the fault status registers, and if we ever implement
that we'll want to distinguish the difference. For the
moment, just add a TODO comment about the bug.
Backports commit d86a9ad33c75ed795f09fb43243d0acecd583f24 from qemu
Currently we use the ldl_phys() function to read page table entries.
With the unassigned_access hook in place, if these hit an unassigned
area of memory then the hook will cause us to wrongly generate
an exception with a fault address matching the address of the
page table entry.
Change to using address_space_ldl() so we can detect and correctly
handle bus errors and give them their correct behaviour of
causing a translation error with a suitable fault status register.
Note that this won't actually take effect until we switch the
over to using the do_translation_failed hook.
Backports commit 3c818dfcc271f5ba298b06f33466ab30f9a28349 from qemu
Currently the ld/st_asi helper functions make calls to the
ld*_phys() and st*_phys() functions for those ASIs which
imply direct accesses to physical addresses. These implicitly
rely on the unassigned_access hook to cause them to generate
an MMU fault if the access fails.
Switch to using the address_space_* functions instead, which
return a MemTxResult that we can check. This means that when
we switch SPARC over to using the do_transaction_failed hook
we'll still get the same MMU faults we did before.
This commit converts the ASIs which do MXCC stream source
and destination accesses.
It's not clear to me whether raising an MMU fault like this
is the correct behaviour if we encounter a bus error, but
we retain the same behaviour that the old unassigned_access
hook would implement.
Backports commit 776095d3cd751a58469b68f652c1ab6785f63652 from qemu
Currently the ld/st_asi helper functions make calls to the
ld*_phys() and st*_phys() functions for those ASIs which
imply direct accesses to physical addresses. These implicitly
rely on the unassigned_access hook to cause them to generate
an MMU fault if the access fails.
Switch to using the address_space_* functions instead, which
return a MemTxResult that we can check. This means that when
we switch SPARC over to using the do_transaction_failed hook
we'll still get the same MMU faults we did before.
This commit converts the ASIs which do "MMU passthrough".
Backports commit b9f5fdad49c74583dcf9fcba0805b148e3992e13 from qemu
Currently the SPARC target uses the old-style do_unassigned_access
hook. We want to switch it over to do_transaction_failed, but to do
this we must first remove all the direct calls in ldst_helper.c to
cpu_unassigned_access(). Factor out the body of the hook function's
code into a new sparc_raise_mmu_fault() and call it from the hook and
from the various places that used to call cpu_unassigned_access().
In passing, this fixes a bug where the code that raised the
MMU exception was directly calling GETPC() from a function that
was several levels deep in the callstack from the original
helper function: the new sparc_raise_mmu_fault() instead takes
the return address as an argument.
Other than the use of retaddr rather than GETPC() and a comment
format fixup, the body of the new function has no changes from
that of the old hook function.
Backports commit c9d793f44620a4793239da73f67758ce5f5ba5d0 from qemu
The maximum level is defined as P_L2_LEVELS and skip is defined with 6
bits, which means if P_L2_LEVELS < (1 << 6), skip never exceeds the
boundary.
Since this check is between two constants, which leverages compiler
to optimize the code based on different configuration.
Backports commit 526ca2360ea1cd947f74c8c6c38b91b9d6fcfdb5 from qemu
In subpage_init(), we will set subpage->sub_section to
PHYS_SECTION_UNASSIGNED by subpage_register. Since
PHYS_SECTION_UNASSIGNED is defined to be 0, and we allocate subpage with
g_malloc0, this means subpage->sub_section is already initialized to 0.
This patch removes the redundant setup for a new subpage and also fix
the code style.
Backports commit b797ab1a15ba8d2b2fc4ec3e1f24d755f6855d05 from qemu
The purpose of these two MAX here is to get the maximum of these three
variables:
A: map->nodes_nb + nodes
B: map->nodes_nb_alloc
C: alloc_hint
We can write it like MAX(A, B, C). Since the if condition says A > B,
this means MAX(A, B, C) = MAX(A, C).
This patch just simplify the calculation a bit.
Backports commit c95cfd040078db8017f74fd3a4d6f798385d960c from qemu
Function phys_page_set() and phys_page_set_level() 's argument *nb*
stands for number of pages to set instead of hardware address.
This would be more proper to use uint64_t instead of hwaddr for its
type.
Backports commit 56b15076805a29673c1a90ea9c3ebef25bfcc912 from qemu
Switch the MIPS target from the old unassigned_access hook to the new
do_transaction_failed hook.
Unlike the old hook, do_transaction_failed is only ever called from
the TCG memory access paths, so there is no need for the "ignore this
if we're using KVM" hack that we were previously using to work around
the way unassigned_access was called for all kinds of memory accesses
to unassigned physical addresses.
The MIPS target does not ever do direct memory reads by physical
address (via either ldl_phys etc or address_space_ldl etc), so the
only memory accesses this affects are the 'normal' guest loads and
stores, which will be handled by the new hook; their behaviour is
unchanged.
Backports commit 4f02a06d50ef0081089ed8cb3ec7c7986e3c95f8 from qemu
Document the use of g_autofree and g_autoptr in glib for automatic
freeing of memory.
Backports commit 821f2967562a1fdc7e52a644963163e6917c4293 from qemu
The split of information between the two docs is rather arbitary and
unclear. It is simpler for contributors if all the information is in
one file.
Backports commit 637f39568fc0bd9848fd9d225d52ab0c4c443ed3 from qemu
There are only two remaining uses of gen_bx_im. In each case, we
know the destination mode -- not changing in the case of gen_jmp
or changing in the case of trans_BLX_i. Use this to simplify the
surrounding code.
For trans_BLX_i, use gen_jmp for the actual branch. For gen_jmp,
use gen_set_pc_im to set up the single-step.
Backports commit eac2f39602e0423adf56be410c9a22c31fec9a81 from qemu
Now that all callers pass a constant value, split the switch
statement into the individual trans_* functions.
Backports commit 279de61a21a1622cb875ead82d6e78c989ba2966 from qemu
Add a check for ARMv6 in trans_CPS. We had this correct in
the T16 path, but had previously forgotten the check on the
A32 and T32 paths.
Backports commit 20556e7bd6111266fbf1d81e4ff7a89bfa5795a7 from qemu
Fold away all of the cases that now just goto illegal_op,
because all of their internal bits are now in decodetree.
Backports commit 590057d969a54de5d97261701c5702b3bebc9c07 from qemu
Fold away all of the cases that now just goto illegal_op,
because all of their internal bits are now in decodetree.
Backports commit f843e77144c9334e244a422848177f2fbef5eb05 from qemu
We have been using store_reg and not store_reg_for_load when writing
back a loaded value into the base register. At first glance this is
incorrect when base == pc, however that case is UNPREDICTABLE.
Backports commit b0e382b8cf365fed8b8c43482029ac7655961a85 from qemu
This has been a TODO item for quite a while. The minimum bit
count for A32 and T16 is 1, and for T32 is 2.
Backports commit 4b222545dbf30b60c033e1cd6eddda612575fd8c from qemu
Prior to v7, for the A32 encoding, this operation wrote an UNKNOWN
value back to the base register. Starting in v7 this is UNPREDICTABLE.
Backports commit 3949f4675d13c587078f8f423845a3a537a22595 from qemu
This includes a minor bug fix to LDM (user), which requires
bit 21 to be 0, which means no writeback.
Backports commit c5c426d4c680f908a1e262091a17b088b5709200 from qemu
In op_bfx, note that tcg_gen_{,s}extract_i32 already checks
for width == 32, so we don't need to special case that here.
Backports commit 86d21e4b509a2835ed79f234f476a4c5191d435b from qemu
Pass the T5 encoding of SUBS PC, LR, #IMM through the normal SUBS path
to make it clear exactly what's happening -- we hit ALUExceptionReturn
along that path.
Backports commit ef11bc3c461e2c650e8bef552146a4b08f81884e from qemu
Document our choice about the T32 CONSTRAINED UNPREDICTABLE behaviour.
This matches the undocumented choice made by the legacy decoder.
Backports commit 4c97f5b2f0fa9b37f9ff497f15411d809e6fd098 from qemu
The m-profile and a-profile decodings overlap. Only return false
for the case of wrong profile; handle UNDEFINED for permission failure
directly. This ensures that we don't accidentally pass an insn that
applies to the wrong profile.
Backports commit d0b26644502103ca97093ef67749812dc1df7eea from qemu
By shifting the 16-bit input left by 16, we can align the desired
portion of the 48-bit product and use tcg_gen_muls2_i32.
Backports commit 485b607d4f393e0de92c922806a68aef22340c98 from qemu
Since all of the inputs and outputs are i32, dispense with
the intermediate promotion to i64 and use tcg_gen_add2_i32.
Backports commit ea96b374641bc429269096d88d4e91ee544273e9 from qemu
Since all of the inputs and outputs are i32, dispense with
the intermediate promotion to i64 and use tcg_gen_mulu2_i32
and tcg_gen_add2_i32.
Backports commit 2409d56454f0d028619fb1002eda86bf240906dd from qemu
Convert the modified immediate form of the data processing insns.
For A32, we can finally remove any code that was intertwined with
the register and register-shifted-register forms.
Backports commit 581c6ebd17c8f56ad52772216e6c6d8cc8997e8b from qemu
Convert the register shifted by register form of the data
processing insns. For A32, we cannot yet remove any code
because the legacy decoder intertwines the immediate form.
Backports commit 5be2c12337f4cbdbda4efe6ab485350f730faaad from qemu
Convert the register shifted by immediate form of the data
processing insns. For A32, we cannot yet remove any code
because the legacy decoder intertwines the reg-shifted-reg
and immediate forms.
Backports commit 25ae32c558182c07fc6ad01b936e9151cbf00c44 from qemu
Add the infrastructure that will become the new decoder.
No instructions adjusted so far.
Backports commit 51409b9e8cfe997b1ac3365df7400e0c6e844437 from qemu
This function already includes the test for an interworking write
to PC from a load. Change the T32 LDM implementation to match the
A32 LDM implementation.
For LDM, the reordering of the tests does not change valid
behaviour because the only case that differs is has rn == 15,
which is UNPREDICTABLE.
Backports commit 69be3e13764111737e1a7a13bb0c231e4d5be756 from qemu
The previous simplification got the order of operands to the
subtraction wrong. Since the 64-bit product is the subtrahend,
we must use a 64-bit subtract to properly compute the borrow
from the low-part of the product.
Fixes: 5f8cd06ebcf5 ("target/arm: Simplify SMMLA, SMMLAR, SMMLS, SMMLSR")
Backports commit e0a0c8322b8ebcdad674f443a3e86db8708d6738 from qemu
The translation table walk for an ATS instruction can result in
various faults. In general these are just reported back via the
PAR_EL1 fault status fields, but in some cases the architecture
requires that the fault is turned into an exception:
* synchronous stage 2 faults of any kind during AT S1E0* and
AT S1E1* instructions executed from NS EL1 fault to EL2 or EL3
* synchronous external aborts are taken as Data Abort exceptions
(This is documented in the v8A Arm ARM DDI0487A.e D5.2.11 and
G5.13.4.)
Backports commit 0710b2fa84a4aeb925422e1e88edac49ed407c79 from qemu
Currently the only part of an ARMCPRegInfo which is allowed to cause
a CPU exception is the access function, which returns a value indicating
that some flavour of UNDEF should be generated.
For the ATS system instructions, we would like to conditionally
generate exceptions as part of the writefn, because some faults
during the page table walk (like external aborts) should cause
an exception to be raised rather than returning a value.
There are several ways we could do this:
* plumb the GETPC() value from the top level set_cp_reg/get_cp_reg
helper functions through into the readfn and writefn hooks
* add extra readfn_with_ra/writefn_with_ra hooks that take the GETPC()
value
* require the ATS instructions to provide a dummy accessfn,
which serves no purpose except to cause the code generation
to emit TCG ops to sync the CPU state
* add an ARM_CP_ flag to mark the ARMCPRegInfo as possibly
throwing an exception in its read/write hooks, and make the
codegen sync the CPU state before calling the hooks if the
flag is set
This patch opts for the last of these, as it is fairly simple
to implement and doesn't require invasive changes like updating
the readfn/writefn hook function prototype signature.
Backports commit 37ff584c15bc3e1dd2c26b1998f00ff87189538c from qemu
Make this a static function private to translate.c.
Thus we can use the same idiom between aarch64 and aarch32
without actually sharing function implementations.
Backports commit 1ce21ba1eaf08b22da5925f3e37fc0b4322da858 from qemu
Despite the fact that the text for the call to gen_exception_insn
is identical for aarch64 and aarch32, the implementation inside
gen_exception_insn is totally different.
This fixes exceptions raised from aarch64.
This reverts commit fb2d3c9a9a.
Order of arguments in helper_ret_stl_mmu() invocations was wrong,
apparently caused by a misplaced multiline copy-and-paste.
Fixes: 6decc57 ("target/mips: Fix MSA instructions ST.<B|H|W|D> on big endian host")
Backports commit abd4393d769d9fe2333b2e83e00f911a78475943 from qemu
This is a left-over from commit
c12b6d70e384c769ca372e15ffd19b3e9f563662 ("pixman: drop submodule")
Backports commit fbb04e760f4818a1ba9cfde0a2571a15cd4f49f7 from qemu
9b9c37c364 ("tcg-sparc: Assume v9 cpu always, i.e. force v8plus in
32-bit mode.", 2012-09-21) removed the need for this variable and
most of the references to it, but this one.
Remove defunct code, no effect or functionality change expected.
Backports commit edd318b7a3c54321ead363ffc1e22ebac5785f1d from qemu
Intel CooperLake cpu adds AVX512_BF16 instruction, defining as
CPUID.(EAX=7,ECX=1):EAX[bit 05].
The patch adds a property for setting the subleaf of CPUID leaf 7 in
case that people would like to specify it.
The release spec link as follows,
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Backports commit 80db491da4ce8b199e0e8d1e23943b20aab82f69 from qemu
The x86 architecture requires that all conversions from floating
point to integer which raise the 'invalid' exception (infinities of
both signs, NaN, and all values which don't fit in the destination
integer) return what the x86 spec calls the "indefinite integer
value", which is 0x8000_0000 for 32-bits or 0x8000_0000_0000_0000 for
64-bits. The softfloat functions return the more usual behaviour of
positive overflows returning the maximum value that fits in the
destination integer format and negative overflows returning the
minimum value that fits.
Wrap the softfloat functions in x86-specific versions which
detect the 'invalid' condition and return the indefinite integer.
Note that we don't use these wrappers for the 3DNow! pf2id and pf2iw
instructions, which do return the minimum value that fits in
an int32 if the input float is a large negative number.
Fixes: https://bugs.launchpad.net/qemu/+bug/1815423
Backports commit 1e8a98b53867f61da9ca09f411288e2085d323c4 from qemu
This patch moves the define of target access alignment earlier from
target/foo/cpu.h to configure.
Suggested in Richard Henderson's reply to "[PATCH 1/4] tcg: TCGMemOp is now
accelerator independent MemOp"
Backports commit 52bf9771fdfce98e98cea36a17a18915be6f6b7f from qemu
We can tell that a decodetree input file is "secondary" when it
uses an argument set marked "!extern". This indicates that at
least one of the insn translation functions will have already
been declared by the "primary" input file, but given only the
secondary we cannot tell which.
Avoid redundant declaration warnings by suppressing them with pragmas.
Backports commit c692079597d98337b6f25deff7599afe39b2a468 from qemu
We should avoid including the whole of softfloat headers in cpu.h and
explicitly include it only where we will be calling softfloat
functions. We can use the -types.h and -helpers.h in cpu.h for the few
bits that are global.
Backports commit 135b03cb9defbd080b8834b30e3d45bed00c6137 from qemu
We should avoid including the whole of softfloat headers in cpu.h and
explicitly include it only where we will be calling softfloat
functions. We can use the -types.h in cpu.h for the few bits that are
global. We also move the restore_snan_bit_mode into internal.h and
include -helpers.h there.
Backports commit 502700d0674919309a19bfd016ea0680c6b7747d from qemu
This is not a normal header and should only be included in the main
softfloat.c file to bring in the various target specific
specialisations. Indeed as it contains non-inlined C functions it is
not even a legal header. Rename it to match our included C convention.
Backports commit 00f43279a3e5e7ea3a0fa853157863663e838e2e from qemu
The macros use the "flags" type and to be consistent if anyone just
needs the macros we should bring in the header we need. There is an
outstanding TODO to audit the use of "flags" and replace with bool at
which point this include could be dropped.
Backports commit 5937fb63a92d54cc4e5270256e4387c4d3a70091 from qemu
There are a bunch of users of the inline helpers who do not need
access to the entire softfloat API. Move those inline helpers into a
new header file which can be included without bringing in the rest of
the world.
Backports commit e34c47ea3fb5f324b58db117b3c010a494c8d6ca from qemu
In our quest to eliminate the home rolled LIT64 macro we fixup usage
inside for m68k's many constants.
Backports commit e23263004d5fea809ad0f78c523f498e04ba788f from qemu
In our quest to eliminate the home rolled LIT64 macro we fixup usage
inside the softfloat code. While we are at it we remove some of the
extraneous spaces to closer fit the house style.
Backports commit e932112420f063776f2b9d9e5512830cd6890a7a from qemu
Remove some more use of LIT64 while making the meaning more clear. We
also avoid the need of casts as the results by definition fit into the
return type.
Backports commit 2c217da0fc9f1127bda804e2a500b8138b02c581 from qemu
This also allows us to remove the extractFloat16exp/frac helpers. We
avoid using the floatXX_pack_raw functions as they are slight overkill
for masking out all but the top bit of the number. The generated code
is almost exactly the same as makes no difference to the
pre-conversion code.
Backports commit e6b405fe00d8e6424a58492b37a1656d1ef0929b from qemu
We have a wrapper that does the right thing from stdint.h so lets use
it for our constants in softfloat-specialize.h
Backports commit f7e81a945737631c19405a39d510d2284257c3ff from qemu
Separate shift + extract low will result in one extra insn
for hosts like RISC-V, MIPS, and Sparc.
Backports commit 664b7e3b97d6376f3329986c465b3782458b0f8b from qemu
All of the inputs to these instructions are 32-bits. Rather than
extend each input to 64-bits and then extract the high 32-bits of
the output, use tcg_gen_muls2_i32 and other 32-bit generator functions.
Backports commit 5f8cd06ebcf57420be8fea4574de2e074de46709 from qemu
Rotate is the more compact and obvious way to swap 16-bit
elements of a 32-bit word.
Backports commit adefba76e8bf10dfb342094d2f5debfeedb1a74d from qemu
The helper function is more documentary, and also already
handles the case of rotate by zero.
Backports commit dd861b3f29be97a9e3cdb9769dcbc0c7d7825185 from qemu
The immediate shift generator functions already test for,
and eliminate, the case of a shift by zero.
Backports commit 464eaa9571fae5867d9aea7d7209c091c8a50223 from qemu
Unless we're guaranteed to always increase ARM_MAX_VQ by a multiple of
four, then we should use DIV_ROUND_UP to ensure we get an appropriate
array size.
Backports commit 46417784d21c89446763f2047228977bdc267895 from qemu
The current implementation of ZCR_ELx matches the architecture, only
implementing the lower four bits, with the rest RAZ/WI. This puts
a strict limit on ARM_MAX_VQ of 16. Make sure we don't let ARM_MAX_VQ
grow without a corresponding update here.
Backports commit 7b351d98709d3f77d6bb18562e1bf228862b0d57 from qemu
Replace x = double_saturate(y) with x = add_saturate(y, y).
There is no need for a separate more specialized helper.
Backports commit 640581a06d14e2d0d3c3ba79b916de6bc43578b0 from qemu
Promote this function from aarch64 to fully general use.
Use it to unify the code sequences for generating illegal
opcode exceptions.
Backports commit 3cb36637157088892e9e33ddb1034bffd1251d3b from qemu
Unlike the other more generic gen_exception{,_internal}_insn
interfaces, breakpoints always refer to the current instruction.
Backports commit 06bcbda3f64d464b6ecac789bce4bd69f199cd68 from qemu
The offset is variable depending on the instruction set.
Passing in the actual value is clearer in intent.
Backpors commit aee828e7541a5895669ade3a4b6978382b6b094a from qemu
We must update s->base.pc_next when we return from the translate_insn
hook to the main translator loop. By incrementing s->base.pc_next
immediately after reading the insn word, "pc_next" contains the address
of the next instruction throughout translation.
All remaining uses of s->pc are referencing the address of the next insn,
so this is now a simple global replacement. Remove the "s->pc" field.
Backports commit a04159166b880b505ccadc16f2fe84169806883d from qemu
Provide a common routine for the places that require ALIGN(PC, 4)
as the base address as opposed to plain PC. The two are always
the same for A32, but the difference is meaningful for thumb mode.
Backports commit 16e0d8234ef9291747332d2c431e46808a060472 from qemu
We currently have 3 different ways of computing the architectural
value of "PC" as seen in the ARM ARM.
The value of s->pc has been incremented past the current insn,
but that is all. Thus for a32, PC = s->pc + 4; for t32, PC = s->pc;
for t16, PC = s->pc + 2. These differing computations make it
impossible at present to unify the various code paths.
With the newly introduced s->pc_curr, we can compute the correct
value for all cases, using the formula given in the ARM ARM.
This changes the behaviour for load_reg() and load_reg_var()
when called with reg==15 from a 32-bit Thumb instruction:
previously they would have returned the incorrect value
of pc_curr + 6, and now they will return the architecturally
correct value of PC, which is pc_curr + 4. This will not
affect well-behaved guest software, because all of the places
we call these functions from T32 code are instructions where
using r15 is UNPREDICTABLE. Using the architectural PC value
here is more consistent with the T16 and A32 behaviour.
Backports commit fdbcf6329d0c2984c55d7019419a72bf8e583c36 from qemu
Add a new field to retain the address of the instruction currently
being translated. The 32-bit uses are all within subroutines used
by a32 and t32. This will become less obvious when t16 support is
merged with a32+t32, and having a clear definition will help.
Convert aarch64 as well for consistency. Note that there is one
instance of a pre-assert fprintf that used the wrong value for the
address of the current instruction.
Backports commit 43722a6d4f0c92f7e7e1e291580039b0f9789df1 from qemu
This function is used in two different contexts, and it will be
clearer if the function is given the address to which it applies.
Backports commit 331b1ca616cb708db30dab68e3262d286e687f24 from qemu
When generating an architectural single-step exception we were
routing it to the "default exception level", which is to say
the same exception level we execute at except that EL0 exceptions
go to EL1. This is incorrect because the debug exception level
can be configured by the guest for situations such as single
stepping of EL0 and EL1 code by EL2.
We have to track the target debug exception level in the TB
flags, because it is dependent on CPU state like HCR_EL2.TGE
and MDCR_EL2.TDE. (That we were previously calling the
arm_debug_target_el() function to determine dc->ss_same_el
is itself a bug, though one that would only have manifested
as incorrect syndrome information.) Since we are out of TB
flag bits unless we want to expand into the cs_base field,
we share some bits with the M-profile only HANDLER and
STACKCHECK bits, since only A-profile has this singlestep.
Fixes: https://bugs.launchpad.net/qemu/+bug/1838913
Backports commit 8bd587c1066f4456ddfe611b571d9439a947d74c from qemu
Factor out code to 'generate a singlestep exception', which is
currently repeated in four places.
To do this we need to also pull the identical copies of the
gen-exception() function out of translate-a64.c and translate.c
into translate.h.
(There is a bug in the code: we're taking the exception to the wrong
target EL. This will be simpler to fix if there's only one place to
do it.)
Backports commit c1d5f50f094ab204accfacc2ee6aafc9601dd5c4 from qemu
While most features are now detected by probing the ID_* registers
kernels can (and do) use MIDR_EL1 for working out of they have to
apply errata. This can trip up warnings in the kernel as it tries to
work out if it should apply workarounds to features that don't
actually exist in the reported CPU type.
Avoid this problem by synthesising our own MIDR value.
Backports commit 2bd5f41c00686a1f847a60824d0375f3df2c26bf from qemu
MemoryRegionSection includes an Int128 'size' field;
on some platforms the compiler causes an alignment of this to
a 128bit boundary, leaving 8 bytes of dead space.
This deadspace can be filled with junk.
Move the size field to the top avoiding unnecessary alignment.
Backports commit c0aca9352d51c102c55fe29ce5c1bf8e74a5183e from qemu
rt==15 is a special case when reading the flags: it means the
destination is APSR. This patch avoids rejecting vmrs apsr_nzcv, fpscr
as illegal instruction.
Backports commit cdc6896659b85f7ed8f7552850312e55170de0c5 from qemu
An attempt to do an exception-return (branch to one of the magic
addresses) in linux-user mode for M-profile should behave like
a normal branch, because linux-user mode is always going to be
in 'handler' mode. This used to work, but we broke it when we added
support for the M-profile security extension in commit d02a8698d7ae2bfed.
In that commit we allowed even handler-mode calls to magic return
values to be checked for and dealt with by causing an
EXCP_EXCEPTION_EXIT exception to be taken, because this is
needed for the FNC_RETURN return-from-non-secure-function-call
handling. For system mode we added a check in do_v7m_exception_exit()
to make any spurious calls from Handler mode behave correctly, but
forgot that linux-user mode would also be affected.
How an attempted return-from-non-secure-function-call in linux-user
mode should be handled is not clear -- on real hardware it would
result in return to secure code (not to the Linux kernel) which
could then handle the error in any way it chose. For QEMU we take
the simple approach of treating this erroneous return the same way
it would be handled on a CPU without the security extensions --
treat it as a normal branch.
The upshot of all this is that for linux-user mode we should never
do any of the bx_excret magic, so the code change is simple.
This ought to be a weird corner case that only affects broken guest
code (because Linux user processes should never be attempting to do
exception returns or NS function returns), except that the code that
assigns addresses in RAM for the process and stack in our linux-user
code does not attempt to avoid this magic address range, so
legitimate code attempting to return to a trampoline routine on the
stack can fall into this case. This change fixes those programs,
but we should also look at restricting the range of memory we
use for M-profile linux-user guests to the area that would be
real RAM in hardware.
Backports commit 9027d3fba605d8f6093342ebe4a1da450d374630 from qemu
The function neon_store_reg32() doesn't free the TCG temp that it
is passed, so the caller must do that. We got this right in most
places but forgot to free the TCG temps in trans_VMOV_64_sp().
Backports commit 38fb634853ac6547326d9f88b9a068d9fc6b4ad4 from qemu
* activate CP0C3_ULRI for CONFIG3, mips
* updated with mips patches
* updated with mips patches
* remove hardcoded config3
* git ignore vscode
* fix spacing issue and turn on floating point
Backports most of commit 24f55a7973278f20f0de21b904851d99d4716263 from
unicorn. Ignores internal core modifications, as this would be
special-casing non-upstreamed behavior.
In Arm v8.0 M-profile CPUs without the Security Extension and also in
v7M CPUs, there is no NSACR register. However, the code we have to handle
the FPU does not always check whether the ARM_FEATURE_M_SECURITY bit
is set before testing whether env->v7m.nsacr permits access to the
FPU. This means that for a CPU with an FPU but without the Security
Extension we would always take a bogus fault when trying to stack
the FPU registers on an exception entry.
We could fix this by adding extra feature bit checks for all uses,
but it is simpler to just make the internal value of nsacr 0xcff
("all non-secure accesses allowed"), since this is not guest
visible when the Security Extension is not present. This allows
us to continue to follow the Arm ARM pseudocode which takes a
similar approach. (In particular, in the v8.1 Arm ARM the register
is documented as reading as 0xcff in this configuration.)
Fixes: https://bugs.launchpad.net/qemu/+bug/1838475
Backports commit 02ac2f7f613b47f6a5b397b20ab0e6b2e7fb89fa from qemu
Most Arm architectural debug exceptions (eg watchpoints) are ignored
if the configured "debug exception level" is below the current
exception level (so for example EL1 can't arrange to get debug exceptions
for EL2 execution). Exceptions generated by the BRK or BPKT instructions
are a special case -- they must always cause an exception, so if
we're executing above the debug exception level then we
must take them to the current exception level.
This fixes a bug where executing BRK at EL2 could result in an
exception being taken at EL1 (which is strictly forbidden by the
architecture).
Fixes: https://bugs.launchpad.net/qemu/+bug/1838277
Backports commit 987a23224218fa3bb3aa0024ad236dcf29ebde9e from qemu
