Our current usage of MMU indexes when EL3 is AArch32 is confused.
Architecturally, when EL3 is AArch32, all Secure code runs under the
Secure PL1&0 translation regime:
* code at EL3, which might be Mon, or SVC, or any of the
other privileged modes (PL1)
* code at EL0 (Secure PL0)
This is different from when EL3 is AArch64, in which case EL3 is its
own translation regime, and EL1 and EL0 (whether AArch32 or AArch64)
have their own regime.
We claimed to be mapping Secure PL1 to our ARMMMUIdx_EL3, but didn't
do anything special about Secure PL0, which meant it used the same
ARMMMUIdx_EL10_0 that NonSecure PL0 does. This resulted in a bug
where arm_sctlr() incorrectly picked the NonSecure SCTLR as the
controlling register when in Secure PL0, which meant we were
spuriously generating alignment faults because we were looking at the
wrong SCTLR control bits.
The use of ARMMMUIdx_EL3 for Secure PL1 also resulted in the bug that
we wouldn't honour the PAN bit for Secure PL1, because there's no
equivalent _PAN mmu index for it.
Fix this by adding two new MMU indexes:
* ARMMMUIdx_E30_0 is for Secure PL0
* ARMMMUIdx_E30_3_PAN is for Secure PL1 when PAN is enabled
The existing ARMMMUIdx_E3 is used to mean "Secure PL1 without PAN"
(and would be named ARMMMUIdx_E30_3 in an AArch32-centric scheme).
These extra two indexes bring us up to the maximum of 16 that the
core code can currently support.
This commit:
* adds the new MMU index handling to the various places
where we deal in MMU index values
* adds assertions that we aren't AArch32 EL3 in a couple of
places that currently use the E10 indexes, to document why
they don't also need to handle the E30 indexes
* documents in a comment why regime_has_2_ranges() doesn't need
updating
Notes for backporting: this commit depends on the preceding revert of
4c2c047469; that revert and this commit should probably be
backported to everywhere that we originally backported 4c2c047469.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2326
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2588
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241101142845.1712482-3-peter.maydell@linaro.org
This reverts commit 4c2c047469.
This commit tried to fix a problem with our usage of MMU indexes when
EL3 is AArch32, using what it described as a "more complicated
approach" where we share the same MMU index values for Secure PL1&0
and NonSecure PL1&0. In theory this should work, but the change
didn't account for (at least) two things:
(1) The design change means we need to flush the TLBs at any point
where the CPU state flips from one to the other. We already flush
the TLB when SCR.NS is changed, but we don't flush the TLB when we
take an exception from NS PL1&0 into Mon or when we return from Mon
to NS PL1&0, and the commit didn't add any code to do that.
(2) The ATS12NS* address translate instructions allow Mon code (which
is Secure) to do a stage 1+2 page table walk for NS. I thought this
was OK because do_ats_write() does a page table walk which doesn't
use the TLBs, so because it can pass both the MMU index and also an
ARMSecuritySpace argument we can tell the table walk that we want NS
stage1+2, not S. But that means that all the code within the ptw
that needs to find e.g. the regime EL cannot do so only with an
mmu_idx -- all these functions like regime_sctlr(), regime_el(), etc
would need to pass both an mmu_idx and the security_space, so they
can tell whether this is a translation regime controlled by EL1 or
EL3 (and so whether to look at SCTLR.S or SCTLR.NS, etc).
In particular, because regime_el() wasn't updated to look at the
ARMSecuritySpace it would return 1 even when the CPU was in Monitor
mode (and the controlling EL is 3). This meant that page table walks
in Monitor mode would look at the wrong SCTLR, TCR, etc and would
generally fault when they should not.
Rather than trying to make the complicated changes needed to rescue
the design of 4c2c047469, we revert it in order to instead take the
route that that commit describes as "the most straightforward" fix,
where we add new MMU indexes EL30_0, EL30_3, EL30_3_PAN to correspond
to "Secure PL1&0 at PL0", "Secure PL1&0 at PL1", and "Secure PL1&0 at
PL1 with PAN".
This revert will re-expose the "spurious alignment faults in
Secure PL0" issue #2326; we'll fix it again in the next commit.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20241101142845.1712482-2-peter.maydell@linaro.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Our current usage of MMU indexes when EL3 is AArch32 is confused.
Architecturally, when EL3 is AArch32, all Secure code runs under the
Secure PL1&0 translation regime:
* code at EL3, which might be Mon, or SVC, or any of the
other privileged modes (PL1)
* code at EL0 (Secure PL0)
This is different from when EL3 is AArch64, in which case EL3 is its
own translation regime, and EL1 and EL0 (whether AArch32 or AArch64)
have their own regime.
We claimed to be mapping Secure PL1 to our ARMMMUIdx_EL3, but didn't
do anything special about Secure PL0, which meant it used the same
ARMMMUIdx_EL10_0 that NonSecure PL0 does. This resulted in a bug
where arm_sctlr() incorrectly picked the NonSecure SCTLR as the
controlling register when in Secure PL0, which meant we were
spuriously generating alignment faults because we were looking at the
wrong SCTLR control bits.
The use of ARMMMUIdx_EL3 for Secure PL1 also resulted in the bug that
we wouldn't honour the PAN bit for Secure PL1, because there's no
equivalent _PAN mmu index for it.
We could fix this in one of two ways:
* The most straightforward is to add new MMU indexes EL30_0,
EL30_3, EL30_3_PAN to correspond to "Secure PL1&0 at PL0",
"Secure PL1&0 at PL1", and "Secure PL1&0 at PL1 with PAN".
This matches how we use indexes for the AArch64 regimes, and
preserves propirties like being able to determine the privilege
level from an MMU index without any other information. However
it would add two MMU indexes (we can share one with ARMMMUIdx_EL3),
and we are already using 14 of the 16 the core TLB code permits.
* The more complicated approach is the one we take here. We use
the same MMU indexes (E10_0, E10_1, E10_1_PAN) for Secure PL1&0
than we do for NonSecure PL1&0. This saves on MMU indexes, but
means we need to check in some places whether we're in the
Secure PL1&0 regime or not before we interpret an MMU index.
The changes in this commit were created by auditing all the places
where we use specific ARMMMUIdx_ values, and checking whether they
needed to be changed to handle the new index value usage.
Note for potential stable backports: taking also the previous
(comment-change-only) commit might make the backport easier.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2326
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240809160430.1144805-3-peter.maydell@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240524232121.284515-8-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This fixes a bug in that neither PLI nor PLDW are present in ARMv6T2,
but are introduced with ARMv7 and ARMv7MP respectively.
For clarity, do not use NOP for PLD.
Note that there is no PLDW (literal). Architecturally in the
T1 encoding of "PLD (literal)" bit 5 is "(0)", which means
that it should be zero and if it is not then the behaviour
is CONSTRAINED UNPREDICTABLE (might UNDEF, NOP, or ignore the
value of the bit).
In our implementation we have patterns for both:
+ PLD 1111 1000 -001 1111 1111 ------------ # (literal)
+ PLD 1111 1000 -011 1111 1111 ------------ # (literal)
and so we effectively ignore the value of bit 5. (This is a
permitted option for this CONSTRAINED UNPREDICTABLE.) This isn't a
behaviour change in this commit, since we previously had NOP lines
for both those patterns.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20240524232121.284515-3-richard.henderson@linaro.org
[PMM: adjusted commit message to note that PLD (lit) T1 bit 5
being 1 is an UNPREDICTABLE case.]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Almost all of the disas_log implementations are identical.
Unify them within translator_loop.
Drop extra Priv/Virt logging from target/riscv.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
To keep the multiple update check, replace insn_start
with insn_start_updated.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The HSTR_EL2 register allows the hypervisor to trap AArch32 EL1 and
EL0 accesses to cp15 registers. We incorrectly implemented this so
they trap to EL1 when we detect the need for a HSTR trap at code
generation time. (The check in access_check_cp_reg() which we do at
runtime to catch traps from EL0 is correctly routing them to EL2.)
Use the correct target EL when generating the code to take the trap.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2226
Fixes: 049edada5e ("target/arm: Make HSTR_EL2 traps take priority over UNDEF-at-EL1")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240325133116.2075362-1-peter.maydell@linaro.org
Now that we have removed TARGET_PAGE_BITS_MIN-6 from
TLB_FLAGS_MASK, we can test for 32-byte alignment.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240301204110.656742-2-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Architecturally, the AArch32 MSR/MRS to/from banked register
instructions are UNPREDICTABLE for attempts to access a banked
register that the guest could access in a more direct way (e.g.
using this insn to access r8_fiq when already in FIQ mode). QEMU has
chosen to UNDEF on all of these.
However, for the case of accessing SPSR_hyp from hyp mode, it turns
out that real hardware permits this, with the same effect as if the
guest had directly written to SPSR. Further, there is some
guest code out there that assumes it can do this, because it
happens to work on hardware: an example Cortex-R52 startup code
fragment uses this, and it got copied into various other places,
including Zephyr. Zephyr was fixed to not use this:
https://github.com/zephyrproject-rtos/zephyr/issues/47330
but other examples are still out there, like the selftest
binary for the MPS3-AN536.
For convenience of being able to run guest code, permit
this UNPREDICTABLE access instead of UNDEFing it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240206132931.38376-5-peter.maydell@linaro.org
Makes gen_intermediate_code() signature target agnostic so the function
can be called from accel/tcg/translate-all.c without target specifics.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20240119144024.14289-9-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
For the Thumb T32 encoding of LDM, if only a single register is
specified in the register list this instruction is UNPREDICTABLE,
with the following choices:
* instruction UNDEFs
* instruction is a NOP
* instruction loads a single register
* instruction loads an unspecified set of registers
Currently we choose to UNDEF (a behaviour chosen in commit
4b222545db in 2019; previously we treated it as "load the
specified single register").
Unfortunately there is real world code out there (which shipped in at
least Android 11, 12 and 13) which incorrectly uses this
UNPREDICTABLE insn on the assumption that it does a single register
load, which is (presumably) what it happens to do on real hardware,
and is also what it does on the equivalent A32 encoding.
Revert to the pre-4b222545dbf30 behaviour of not UNDEFing
for this T32 encoding.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1799
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230927101853.39288-1-peter.maydell@linaro.org
Allow the name 'cpu_env' to be used for something else.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20230831030904.1194667-3-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230831232441.66020-5-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Perform the check for EL2 enabled in the security space and the
TIDCP bit in an out-of-line helper.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230831232441.66020-4-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In commit 0b188ea05a we changed the implementation of
trans_CSEL() to use tcg_constant_i32(). However, this change
was incorrect, because the implementation of the function
sets up the TCGv_i32 rn and rm to be either zero or else
a TCG temp created in load_reg(), and these TCG temps are
then in both cases written to by the emitted TCG ops.
The result is that we hit a TCG assertion:
qemu-system-arm: ../../tcg/tcg.c:4455: tcg_reg_alloc_mov: Assertion `!temp_readonly(ots)' failed.
(or on a non-debug build, just produce a garbage result)
Adjust the code so that rn and rm are always writeable
temporaries whether the instruction is using the special
case "0" or a normal register as input.
Cc: qemu-stable@nongnu.org
Fixes: 0b188ea05a ("target/arm: Use tcg_constant in trans_CSEL")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230727103906.2641264-1-peter.maydell@linaro.org
Let finalize_memop_atom be the new basic function, with
finalize_memop and finalize_memop_pair testing FEAT_LSE2
to apply the appropriate atomicity.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230530191438.411344-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Move most includes from *translate*.c to translate.h, ensuring
that we get the ordering correct. Ensure cpu.h is first.
Use disas/disas.h instead of exec/log.h.
Drop otherwise unused includes.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
New wrapper around gen_io_start which takes care of the USE_ICOUNT
check, as well as marking the DisasContext to end the TB.
Remove exec/gen-icount.h.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Create helper-proto-common.h without the target specific portion.
Use that in tcg-op-common.h. Include helper-proto.h in target/arm
and target/hexagon before helper-info.c.inc; all other targets are
already correct in this regard.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Create helper-gen-common.h without the target specific portion.
Use that in tcg-op-common.h. Reorg headers in target/arm to
ensure that helper-gen.h is included before helper-info.c.inc.
All other targets are already correct in this regard.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for compiling tcg/ only once, eliminate
the all_helpers array. Instantiate the info structs for
the generic helpers in accel/tcg/, and the structs for
the target-specific helpers in each translate.c.
Since we don't see all of the info structs at startup,
initialize at first use, using g_once_init_* to make
sure we don't race while doing so.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been included via tcg-op-common.h via tcg-op.h,
but that is going away.
It is needed for inlines within translator.h, so we might as well
do it there and not individually in each translator c file.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In several places in the 32-bit Arm translate.c, we try to use
load_cpu_field() to load from a CPUARMState field into a TCGv_i32
where the field is actually 64-bit. This works on little-endian
hosts, but gives the wrong half of the register on big-endian.
Add a new load_cpu_field_low32() which loads the low 32 bits
of a 64-bit field into a TCGv_i32. The new macro includes a
compile-time check against accidentally using it on a field
of the wrong size. Use it to fix the two places in the code
where we were using load_cpu_field() on a 64-bit field.
This fixes a bug where on big-endian hosts the guest would
crash after executing an ERET instruction, and a more corner
case one where some UNDEFs for attempted accesses to MSR
banked registers from Secure EL1 might go to the wrong EL.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230424153909.1419369-2-peter.maydell@linaro.org
In commit 049edada we added some code to handle HSTR_EL2 traps, which
we did as an inline "conditionally branch over a
gen_exception_insn()". Unfortunately this fails to take account of
the fact that gen_exception_insn() will set s->base.is_jmp to
DISAS_NORETURN. That means that at the end of the TB we won't
generate the necessary code to handle the "branched over the trap and
continued normal execution" codepath. The result is that the TCG
main loop thinks that we stopped execution of the TB due to a
situation that only happens when icount is enabled, and hits an
assertion. Explicitly set is_jmp back to DISAS_NEXT so we generate
the correct code for when execution continues past this insn.
Note that this only happens for cpreg reads; writes will call
gen_lookup_tb() which generates a valid end-of-TB.
Fixes: 049edada ("target/arm: Make HSTR_EL2 traps take priority over UNDEF-at-EL1")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1551
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230330101900.2320380-1-peter.maydell@linaro.org
Reorg temporary usage so that we can use tcg_constant_i32.
tcg_gen_deposit_i32 already has a width == 32 special case,
so remove the check here.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Translators are no longer required to free tcg temporaries.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This field was only used to avoid freeing globals.
Since we no longer free any temps, this is dead.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Translators are no longer required to free tcg temporaries.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since tcg_temp_new_* is now identical, use those.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for returning the number of insns generated
via the same pointer. Adjust only the prototypes so far.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-7-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Introduce the target/arm/tcg directory. Its purpose is to hold the TCG
code that is selected by CONFIG_TCG.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
