The syndrome register value always has an IL field at bit 25, which
is 0 for a trap on a 16 bit instruction, and 1 for a trap on a 32
bit instruction (or for exceptions which aren't traps on a known
instruction, like PC alignment faults). This means that our
syn_*() functions should always either take an is_16bit argument to
determine whether to set the IL bit, or else unconditionally set it.
We missed setting the IL bit for the syndrome for three kinds of trap:
* an SVE access exception
* a pointer authentication check failure
* a BTI (branch target identification) check failure
All of these traps are AArch64 only, and so the instruction causing
the trap is always 64 bit. This means we can unconditionally set
the IL bit in the syn_*() function.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20231120150121.3458408-1-peter.maydell@linaro.org
Cc: qemu-stable@nongnu.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
The FEAT_MOPS memory operations can raise a Memory Copy or Memory Set
exception if a copy or set instruction is executed when the CPU
register state is not correct for that instruction. Define the
usual syn_* function that constructs the syndrome register value
for these exceptions.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230912140434.1333369-5-peter.maydell@linaro.org
The function takes the fields as filled in by
the Arm ARM pseudocode for TakeGPCException.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230620124418.805717-18-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Implement the HFGITR_EL2.ERET fine-grained trap. This traps
execution from AArch64 EL1 of ERET, ERETAA and ERETAB. The trap is
reported with a syndrome value of 0x1a.
The trap must take precedence over a possible pointer-authentication
trap for ERETAA and ERETAB.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Fuad Tabba <tabba@google.com>
Message-id: 20230130182459.3309057-21-peter.maydell@linaro.org
Message-id: 20230127175507.2895013-21-peter.maydell@linaro.org
This will be used for raising various traps for SME.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220620175235.60881-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
With ARMv8, this field is always RES0.
With ARMv7, targeting EL2 and TA=0, it is always 0xA.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220609202901.1177572-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Virtual SError exceptions are raised by setting HCR_EL2.VSE,
and are routed to EL1 just like other virtual exceptions.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220506180242.216785-16-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For A64, any input to an indirect branch can cause this.
For A32, many indirect branch paths force the branch to be aligned,
but BXWritePC does not. This includes the BX instruction but also
other interworking changes to PC. Prior to v8, this case is UNDEFINED.
With v8, this is CONSTRAINED UNPREDICTABLE and may either raise an
exception or force align the PC.
We choose to raise an exception because we have the infrastructure,
it makes the generated code for gen_bx simpler, and it has the
possibility of catching more guest bugs.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In v8A, the PSTATE.IL bit is set for various kinds of illegal
exception return or mode-change attempts. We already set PSTATE.IL
(or its AArch32 equivalent CPSR.IL) in all those cases, but we
weren't implementing the part of the behaviour where attempting to
execute an instruction with PSTATE.IL takes an immediate exception
with an appropriate syndrome value.
Add a new TB flags bit tracking PSTATE.IL/CPSR.IL, and generate code
to take an exception instead of whatever the instruction would have
been.
PSTATE.IL and CPSR.IL change only on exception entry, attempted
exception exit, and various AArch32 mode changes via cpsr_write().
These places generally already rebuild the hflags, so the only place
we need an extra rebuild_hflags call is in the illegal-return
codepath of the AArch64 exception_return helper.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210821195958.41312-2-richard.henderson@linaro.org
Message-Id: <20210817162118.24319-1-peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[rth: Added missing returns; set IL bit in syndrome]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In v7A, the HSTR register has a TJDBX bit which traps NS EL0/EL1
access to the JOSCR and JMCR trivial Jazelle registers, and also BXJ.
Implement these traps. In v8A this HSTR bit doesn't exist, so don't
trap for v8A CPUs.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210816180305.20137-3-peter.maydell@linaro.org
Move everything related to syndromes to a new file,
which can be shared with linux-user.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210212184902.1251044-26-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
