Updating the NS stack pointer via MSR to SP_NS should include
a check whether the new SP value is below the stack limit.
No other kinds of update to the various stack pointer and
limit registers via MSR should perform a check.
Backports commit 167765f0739e4a108e8c2e2ff2f37917df5658f9 from qemu
Add the v8M stack checks for the VLDM/VSTM
(aka VPUSH/VPOP) instructions. This code is currently
unreachable because we haven't yet implemented M profile
floating point support, but since the change is simple,
we add it now because otherwise we're likely to forget to
do it later.
Backports commit 8a954faf5412d5073d585d85a1da63a09bb5d84e from qemu
Add v8M stack checks for the 16-bit Thumb push/pop
encodings: STMDB, STMFD, LDM, LDMIA, LDMFD.
Backports commit aa369e5c08bbe2748d2be96f13f4ef469a4d3080 from qemu
Add v8M stack checks for the instructions in the T32
"load/store single" encoding class: these are the
"immediate pre-indexed" and "immediate, post-indexed"
LDR and STR instructions.
Backports commit 0bc003bad9752afc61624cb680226c922f34f82c from qemu
Add the v8M stack checks for:
* LDM (T2 encoding)
* STM (T2 encoding)
This includes the 32-bit encodings of the instructions listed
in v8M ARM ARM rule R_YVWT as
* LDM, LDMIA, LDMFD
* LDMDB, LDMEA
* POP (multiple registers)
* PUSH (muliple registers)
* STM, STMIA, STMEA
* STMDB, STMFD
We perform the stack limit before doing any other part
of the load or store.
Backports commit 7c0ed88e7d6bee3e55c3d8935c46226cb544191a from qemu
Add the v8M stack checks for:
* LDRD (immediate)
* STRD (immediate)
Loads and stores are more complicated than ADD/SUB/MOV, because we
must ensure that memory accesses below the stack limit are not
performed, so we can't simply do the check when we actually update
SP.
For these instructions, if the stack limit check triggers
we must not:
* perform any memory access below the SP limit
* update PC, SP or the load/store base register
but it is IMPDEF whether we:
* perform any accesses above or equal to the SP limit
* update destination registers for loads
For QEMU we choose to always check the limit before doing any other
part of the load or store, so we won't update any registers or
perform any memory accesses.
It is UNKNOWN whether the limit check triggers for a load or store
where the initial SP value is below the limit and one of the stores
would be below the limit, but the writeback moves SP to above the
limit. For QEMU we choose to trigger the check in this situation.
Note that limit checks happen only for loads and stores which update
SP via writeback; they do not happen for loads and stores which
simply use SP as a base register.
Backports commit 910d7692e5b60f2c2d08cc3d6d36076e85b6a69d from qemu
Add checks for breaches of the v8M stack limit when the
stack pointer is decremented to push the exception frame
for exception entry.
Note that the exception-entry case is unique in that the
stack pointer is updated to be the limit value if the limit
is hit (per rule R_ZLZG).
Backports commit c32da7aa6205a5ff62ae8d5062f7cad0eae4c1fd from qemu
Add some comments to the Thumb decoder indicating what bits
of the instruction have been decoded at various points in
the code.
This is not an exhaustive set of comments; we're gradually
adding comments as we work with particular bits of the code.
Backports commit a2d12f0f34e9c5ef8a193556fde983aa186fa73a from qemu
Add code to insert calls to a helper function to do the stack
limit checking when we handle these forms of instruction
that write to SP:
* ADD (SP plus immediate)
* ADD (SP plus register)
* SUB (SP minus immediate)
* SUB (SP minus register)
* MOV (register)
Backports commit 5520318939fea5d659bf808157cd726cb967b761 from qemu
We're going to want v7m_using_psp() in op_helper.c in the
next patch, so move it from helper.c to internals.h.
Backports commit 5529bf188d996391ff52a0e1801daf9c6a6bfcb0 from qemu
Define EXCP_STKOF, and arrange for it to cause us to take
a UsageFault with CFSR.STKOF set.
Backports commit 86f026de22d8854eecc004af44895de74225794f from qemu
The Arm v8M architecture includes hardware stack limit checking.
When certain instructions update the stack pointer, if the new
value of SP is below the limit set in the associated limit register
then an exception is taken. Add a TB flag that tracks whether
the limit-checking code needs to be emitted.
Backports commit 4730fb85035e99c909db7d14ef76cd17f28f4423 from qemu
There is quite a lot of code required to compute cpu_mem_index,
or even put together the full TCGMemOpIdx. This can easily be
done at translation time.
Backports commit 500d04843ba953dc4560e44f04001efec38c14a6 from qemu
This implements the feature for softmmu, and moves the
main loop out of a macro and into a function.
Backports commit 116347ce20bb7b5cac17bf2b0e6f607530b50862 from qemu
We can choose the endianness at translation time, rather than
re-computing it at execution time.
Backports commit 28d57f2dc59c287e1c40239509b0a325fd00e32f from qemu
We can choose the endianness at translation time, rather than
re-computing it at execution time.
Backports commit 7d0a57a2e1cea188b9023261a404d7a211117230 from qemu
This fixes the endianness problem for softmmu, and moves
the main loop out of a macro and into an inlined function.
Backports commit 78cf1b886aa1b95c97fc5114641515c2892bb240 from qemu
This fixes the endianness problem for softmmu, and moves
the main loop out of a macro and into an inlined function.
Backports commit d4f75f25b43041e7a46d12352b3c70ae457d8cea from qemu
This fixes the endianness problem for softmmu, and moves the
main loop out of a macro and into an inlined function
Backports commit 9fd46c8362e0a45d04ccceae7051d06dd65c1d57 from qemu
Use the same *_tlb primitives as we use for ld1.
For linux-user, this hoists the set of helper_retaddr. For softmmu,
hoists the computation of the current mmu_idx outside the loop,
fixes the endianness problem, and moves the main loop out of a
macro and into an inlined function.
Backports commit f27d4dc2af0de9b7b45c955882b8420905c6efe8 from qemu
Uses tlb_vaddr_to_host for correct operation with softmmu.
Optimize for accesses within a single page or pair of pages.
Backports commit 9123aeb6fcb14e0955ebe4e2a613802cfa0503ea from qemu
The 16-byte load only uses 16 predicate bits. But while
reusing the other load infrastructure, we find other bits
that are set and trigger an assert. To avoid this and
retain the assert, zero-extend the predicate that we pass
to the LD1 helper.
Backports commit 2a99ab2b3545133961de034df27e24f4c22e3707 from qemu
Use the existing helpers to determine if (1) the fpu is enabled,
(2) sve state is enabled, and (3) the current sve vector length.
Backports commit ced3155141755ba244c988c72c4bde32cc819670 from qemu
SVE vector length can change when changing EL, or when writing
to one of the ZCR_ELn registers.
For correctness, our implementation requires that predicate bits
that are inaccessible are never set. Which means noticing length
changes and zeroing the appropriate register bits.
Backports commit 0ab5953b00b3165877d00cf75de628c51670b550 from qemu
We are going to want to determine whether sve is enabled
for EL other than current.
Backports commit 2de7ace292cf7846b0cda0e940272d2cb0e06859 from qemu
Check for EL3 before testing CPTR_EL3.EZ. Return 0 when the exception
should be routed via AdvSIMDFPAccessTrap. Mirror the structure of
CheckSVEEnabled more closely.
Fixes: 5be5e8eda78
Backports commit 60eed0869d68b91eff71cc0a0facb01983726a5d from qemu
Given that the only field defined for this new register may only
be 0, we don't actually need to change anything except the name.
Backports commit 9516d7725ec1deaa6ef5ccc5a26d005650d6c524 from qemu
A cut-and-paste error meant we were reading r4 from the v8M
callee-saves exception stack frame twice. This is harmless
since it just meant we did two memory accesses to the same
location, but it's unnecessary. Delete it.
Backports commit e5ae4d0c063fbcca4cbbd26bcefbf1760cfac2aa from qemu
In v7m_exception_taken() we were incorrectly using a
"LR bit EXCRET.ES is 1" check when it should be 0
(compare the pseudocode ExceptionTaken() function).
This meant we didn't stack the callee-saved registers
when tailchaining from a NonSecure to a Secure exception.
Backports commit 7b73a1ca05b33d42278ce29cea4652e22d408165 from qemu
The ARMv8 architecture defines that an AArch32 CPU starts
in SVC mode, unless EL2 is the highest available EL, in
which case it starts in Hyp mode. (In ARMv7 a CPU with EL2
but not EL3 was not a valid configuration, but we don't
specifically reject this if the user asks for one.)
Backports commit 060a65df056a5d6ca3a6a91e7bf150ca1fbccddf from qemu
Not only are the sve-related tb_flags fields unused when SVE is
disabled, but not all of the cpu registers are initialized properly
for computing same. This can corrupt other fields by ORing in -1,
which might result in QEMU crashing.
This bug was not present in 3.0, but this patch is cc'd to
stable because adf92eab90e3f5f34c285 where the bug was
introduced was marked for stable.
Backports commit e79b445d896deb61909be52b61b87c98a9ed96f7 from qemu
Following the bulk conversion of the iwMMXt code, there are
just a handful of hard coded tabs in target/arm; fix them.
This is a whitespace-only patch.
Backports commit 6e0fafe2ef02378c696e7cf84ef41511e3b3b81a from qemu
Untabify the arm iwmmxt_helper.c. This affects only the iwMMXt code.
We've never touched that code in years, so it's not going to get
fixed up by our "change when touched" process, and a bulk change is
not going to be too disruptive.
This commit was produced using Emacs "untabify" (plus one
by-hand removal of a space to fix a checkpatch nit); it is
a whitespace-only change.
Backports commit 67aed15551f9814712d5ac25a155919b34fbd627 from qemu
On 32-bit exception entry, CPSR.J must always be set to 0
(see v7A Arm ARM DDI0406C.c B1.8.5). CPSR.IL must also
be cleared on 32-bit exception entry (see v8A Arm ARM
DDI0487C.a G1.10).
Clear these bits. (This fixes a bug which will never be noticed
by non-buggy guests.)
Backports commit 829f9fd394ab082753308cbda165c13eaf8fae49 from qemu
Factor out the code which changes the CPU state so as to
actually take an exception to AArch32. We're going to want
to use this for handling exception entry to Hyp mode.
Backports commit dea8378bb3e86f2c6bd05afb3927619f7c51bb47 from qemu
