We already squash the ID register field for FEAT_SPE (the Statistical
Profiling Extension) because TCG does not implement it and if we
advertise it to the guest the guest will crash trying to look at
non-existent system registers. Do the same for some other features
which a real hardware Neoverse-V1 implements but which TCG doesn't:
* FEAT_TRF (Self-hosted Trace Extension)
* Trace Macrocell system register access
* Memory mapped trace
* FEAT_AMU (Activity Monitors Extension)
* FEAT_MPAM (Memory Partitioning and Monitoring Extension)
* FEAT_NV (Nested Virtualization)
Most of these, like FEAT_SPE, are "introspection/trace" type features
which QEMU is unlikely to ever implement. The odd-one-out here is
FEAT_NV -- we could implement that and at some point we probably
will.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230704130647.2842917-2-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Unlike architectures with precise self-modifying code semantics
(e.g. x86) ARM processors do not maintain coherency for instruction
execution and memory, requiring an instruction synchronization
barrier on every core that will execute the new code, and on many
models also the explicit use of cache management instructions.
While this is required to make JITs work on actual hardware, QEMU
has gotten away with not handling this since it does not emulate
caches, and unconditionally invalidates code whenever the softmmu
or the user-mode page protection logic detects that code has been
modified.
Unfortunately the latter does not work in the face of dual-mapped
code (a common W^X workaround), where one page is executable and
the other is writable: user-mode has no way to connect one with the
other as that is only known to the kernel and the emulated
application.
This commit works around the issue by telling software that
instruction cache invalidation is required by clearing the
CPR_EL0.DIC flag (regardless of whether the emulated processor
needs it), and then invalidating code in IC IVAU instructions.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1034
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: John Högberg <john.hogberg@ericsson.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 168778890374.24232.3402138851538068785-1@git.sr.ht
[PMM: removed unnecessary AArch64 feature check; moved
"clear CTR_EL1.DIC" code up a bit so it's not in the middle
of the vfp/neon related tests]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Cortex A7 CPUs with an FPU implementing VFPv4 without NEON support
have 16 64-bit FPU registers and not 32 registers. Let users set the
number of VFP registers with a CPU property.
The primary use case of this property is for the Cortex A7 of the
Aspeed AST2600 SoC.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Accessing EL0-accessible Debug Communication Channel (DCC) registers in
user mode emulation is currently enabled. However, it does not match
Linux behavior as Linux sets MDSCR_EL1.TDCC on startup to disable EL0
access to DCC (see __cpu_setup() in arch/arm64/mm/proc.S).
This patch fixes access_tdcc() to check MDSCR_EL1.TDCC for EL0 and sets
MDSCR_EL1.TDCC for user mode emulation to match Linux.
Signed-off-by: Zhuojia Shen <chaosdefinition@hotmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: DS7PR12MB630905198DD8E69F6817544CAC4EA@DS7PR12MB6309.namprd12.prod.outlook.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This reverts commit b320e21c48,
which accidentally broke TCG, because it made the TCG -cpu max
report the presence of MTE to the guest even if the board hadn't
enabled MTE by wiring up the tag RAM. This meant that if the guest
then tried to use MTE QEMU would segfault accessing the
non-existent tag RAM:
==346473==ERROR: UndefinedBehaviorSanitizer: SEGV on unknown address (pc 0x55f328952a4a bp 0x00000213a400 sp 0x7f7871859b80 T346476)
==346473==The signal is caused by a READ memory access.
==346473==Hint: this fault was caused by a dereference of a high value address (see register values below). Disassemble the provided pc to learn which register was used.
#0 0x55f328952a4a in address_space_to_flatview /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/memory.h:1108:12
#1 0x55f328952a4a in address_space_translate /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/memory.h:2797:31
#2 0x55f328952a4a in allocation_tag_mem /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-clang/../../target/arm/tcg/mte_helper.c:176:10
#3 0x55f32895366c in helper_stgm /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-clang/../../target/arm/tcg/mte_helper.c:461:15
#4 0x7f782431a293 (<unknown module>)
It's also not clear that the KVM logic is correct either:
MTE defaults to on there, rather than being only on if the
board wants it on.
Revert the whole commit for now so we can sort out the issues.
(We didn't catch this in CI because we have no test cases in
avocado that use guests with MTE support.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230519145808.348701-1-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Extend the 'mte' property for the virt machine to cover KVM as
well. For KVM, we don't allocate tag memory, but instead enable the
capability.
If MTE has been enabled, we need to disable migration, as we do not
yet have a way to migrate the tags as well. Therefore, MTE will stay
off with KVM unless requested explicitly.
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230428095533.21747-2-cohuck@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When building with --disable-tcg on Darwin we get:
target/arm/cpu.c:725:16: error: incomplete definition of type 'struct TCGCPUOps'
cc->tcg_ops->do_interrupt(cs);
~~~~~~~~~~~^
Commit 083afd18a9 ("target/arm: Restrict cpu_exec_interrupt()
handler to sysemu") limited this block to system emulation,
but neglected to also limit it to TCG.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Message-id: 20221209110823.59495-1-philmd@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
An exception targeting EL2 from lower EL is actually maskable when
HCR_E2H and HCR_TGE are both set. This applies to both secure and
non-secure Security state.
We can remove the conditions that try to suppress masking of
interrupts when we are Secure and the exception targets EL2 and
Secure EL2 is disabled. This is OK because in that situation
arm_phys_excp_target_el() will never return 2 as the target EL. The
'not if secure' check in this function was originally written before
arm_hcr_el2_eff(), and back then the target EL returned by
arm_phys_excp_target_el() could be 2 even if we were in Secure
EL0/EL1; but it is no longer needed.
Signed-off-by: Ake Koomsin <ake@igel.co.jp>
Message-id: 20221017092432.546881-1-ake@igel.co.jp
[PMM: Add commit message paragraph explaining why it's OK to
remove the checks on secure and SCR_EEL2]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The availability of tb->pc will shortly be conditional.
Introduce accessor functions to minimize ifdefs.
Pass around a known pc to places like tcg_gen_code,
where the caller must already have the value.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The newly added neoverse-n1 CPU has ID register values which indicate
the presence of the Statistical Profiling Extension, because the real
hardware has this feature. QEMU's TCG emulation does not yet
implement SPE, though (not even as a minimal stub implementation), so
guests will crash if they try to use it because the SPE system
registers don't exist.
Force ID_AA64DFR0_EL1.PMSVer to 0 in CPU realize for TCG, so that
we don't advertise to the guest a feature that doesn't exist.
(We could alternatively do this by editing the value that
aarch64_neoverse_n1_initfn() sets for this ID register, but
suppressing the field in realize means we won't re-introduce this bug
when we add other CPUs that have SPE in hardware, such as the
Neoverse-V1.)
An example of a non-booting guest is current mainline Linux (5.19),
when booting in EL2 on the virt board (ie with -machine
virtualization=on).
Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Message-id: 20220811131127.947334-1-peter.maydell@linaro.org
Change the representation of the TCR_EL* registers in the CPU state
struct from struct TCR to uint64_t. This allows us to drop the
custom vmsa_ttbcr_raw_write() function, moving the "enforce RES0"
checks to their more usual location in the writefn
vmsa_ttbcr_write(). We also don't need the resetfn any more.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220714132303.1287193-7-peter.maydell@linaro.org
Mirror the properties for SVE. The main difference is
that any arbitrary set of powers of 2 may be supported,
and not the stricter constraints that apply to SVE.
Include a property to control FEAT_SME_FA64, as failing
to restrict the runtime to the proper subset of insns
could be a major point for bugs.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20220620175235.60881-18-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This will be used for both Normal and Streaming SVE, and the value
does not necessarily come from ZCR_ELx. While we're at it, emphasize
the units in which the value is returned.
Patch produced by
git grep -l sve_zcr_len_for_el | \
xargs -n1 sed -i 's/sve_zcr_len_for_el/sve_vqm1_for_el/g'
and then adding a function comment.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220607203306.657998-13-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Simplify freeing cp_regs hash table entries by using a single
allocation for the entire value.
This fixes a theoretical bug if we were to ever free the entire
hash table, because we've been installing string literal constants
into the cpreg structure in define_arm_vh_e2h_redirects_aliases.
However, at present we only free entries created for AArch32
wildcard cpregs which get overwritten by more specific cpregs,
so this bug is never exposed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20220501055028.646596-13-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
