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
Changing the name to Snowridge from SnowRidge-Server.
There is no client model of Snowridge, so "-Server" is unnecessary.
Removing CPUID_EXT_VMX from Snowridge cpu feature list.
Backports commit ff656fcd338a70c4d9783a800733c4ab3806e5b0 from qemu
In arm_cpu_realizefn() we make several assertions about the values of
guest ID registers:
* if the CPU provides AArch32 v7VE or better it must advertise the
ARM_DIV feature
* if the CPU provides AArch32 A-profile v6 or better it must
advertise the Jazelle feature
These are essentially consistency checks that our ID register
specifications in cpu.c didn't accidentally miss out a feature,
because increasingly the TCG emulation gates features on the values
in ID registers rather than using old-style checks of ARM_FEATURE_FOO
bits.
Unfortunately, these asserts can cause problems if we're running KVM,
because in that case we don't control the values of the ID registers
-- we read them from the host kernel. In particular, if the host
kernel is older than 4.15 then it doesn't expose the ID registers via
the KVM_GET_ONE_REG ioctl, and we set up dummy values for some
registers and leave the rest at zero. (See the comment in
target/arm/kvm64.c kvm_arm_get_host_cpu_features().) This set of
dummy values is not sufficient to pass our assertions, and so on
those kernels running an AArch32 guest on AArch64 will assert.
We could provide a more sophisticated set of dummy ID registers in
this case, but that still leaves the possibility of a host CPU which
reports bogus ID register values that would cause us to assert. It's
more robust to only do these ID register checks if we're using TCG,
as that is the only case where this is truly a QEMU code bug.
Backports commit 8f4821d77e465bc2ef77302d47640d5a43d92b30 from qemu
Reported by GCC9 when building with -Wimplicit-fallthrough=2:
target/arm/helper.c: In function ‘arm_cpu_do_interrupt_aarch32_hyp’:
target/arm/helper.c:7958:14: error: this statement may fall through [-Werror=implicit-fallthrough=]
7958 | addr = 0x14;
| ~~~~~^~~~~~
target/arm/helper.c:7959:5: note: here
7959 | default:
| ^~~~~~~
cc1: all warnings being treated as errors
Backports commit 9bbb4ef991fa93323f87769a6e217c2b9273a128 from qemu
pconfig feature was added in 5131dc433df and removed in 712f807e196.
This patch mark this feature as known to QEMU and removed by
intentinally. This follows the convention of 9ccb9784b57 and f1a23522b03
dealing with 'osxsave' and 'ospke'.
Backports commit 2924ab02c28ce8d32da144a6ae8bfc5a8d7e072b from qemu
In the M-profile architecture, when we do a vector table fetch and it
fails, we need to report a HardFault. Whether this is a Secure HF or
a NonSecure HF depends on several things. If AIRCR.BFHFNMINS is 0
then HF is always Secure, because there is no NonSecure HardFault.
Otherwise, the answer depends on whether the 'underlying exception'
(MemManage, BusFault, SecureFault) targets Secure or NonSecure. (In
the pseudocode, this is handled in the Vector() function: the final
exc.isSecure is calculated by looking at the exc.isSecure from the
exception returned from the memory access, not the isSecure input
argument.)
We weren't doing this correctly, because we were looking at
the target security domain of the exception we were trying to
load the vector table entry for. This produces errors of two kinds:
* a load from the NS vector table which hits the "NS access
to S memory" SecureFault should end up as a Secure HardFault,
but we were raising an NS HardFault
* a load from the S vector table which causes a BusFault
should raise an NS HardFault if BFHFNMINS == 1 (because
in that case all BusFaults are NonSecure), but we were raising
a Secure HardFault
Correct the logic.
We also fix a comment error where we claimed that we might
be escalating MemManage to HardFault, and forgot about SecureFault.
(Vector loads can never hit MPU access faults, because they're
always aligned and always use the default address map.)
Backports commit 51c9122e92b776a3f16af0b9282f1dc5012e2a19 from qemu
The ARMv5 architecture didn't specify detailed per-feature ID
registers. Now that we're using the MVFR0 register fields to
gate the existence of VFP instructions, we need to set up
the correct values in the cpu->isar structure so that we still
provide an FPU to the guest.
This fixes a regression in the arm926 and arm1026 CPUs, which
are the only ones that both have VFP and are ARMv5 or earlier.
This regression was introduced by the VFP refactoring, and more
specifically by commits 1120827fa182f0e76 and 266bd25c485597c,
which accidentally disabled VFP short-vector support and
double-precision support on these CPUs.
Backports commit cb7cef8b32033f6284a47d797edd5c19c5491698 from qemu
When we converted to using feature bits in 602f6e42cfbf we missed out
the fact (dp && arm_dc_feature(s, ARM_FEATURE_V8)) was supported for
-cpu max configurations. This caused a regression in the GCC test
suite. Fix this by setting the appropriate bits in mvfr1.FPHP to
report ARMv8-A with FP support (but not ARMv8.2-FP16).
Fixes: https://bugs.launchpad.net/qemu/+bug/1836078
Backports commit 45b1a243b81a7c9ae56235937280711dd9914ca7 from qemu
In commit e9d652824b0 we extracted the vfp_set_fpscr_to_host()
function but failed at calling it in the correct place, we call
it after xregs[ARM_VFP_FPSCR] is modified.
Fix by calling this function before we update FPSCR.
Backports commit 85795187f416326f87177cabc39fae1911f04c50 from qemu
Off by one error in the EL2 and EL3 tests. Remove the test
against EL3 entirely, since it must always be true.
Backports commit 6a02a73211c5bc634fccd652777230954b83ccba from qemu
Add new version of Cascadelake-Server CPU model, setting
stepping=5 and enabling the IA32_ARCH_CAPABILITIES MSR
with some flags.
The new feature will introduce a new host software requirement,
breaking our CPU model runnability promises. This means we can't
enable the new CPU model version by default in QEMU 4.1, because
management software isn't ready yet to resolve CPU model aliases.
This is why "pc-*-4.1" will keep returning Cascadelake-Server-v1
if "-cpu Cascadelake-Server" is specified.
Includes a test case to ensure the right combinations of
machine-type + CPU model + command-line feature flags will work
as expected.
Backports commit fd63c6d1a5f77d689ee06f6561677c012a988223 from qemu
The old CPU models will be just aliases for specific versions of
the original CPU models.
Backports commit 53db89d93bebe70a3e7f4c45933deffcf3e7cb62 from qemu
Add versions of CPU models that are equivalent to their -IBRS,
-noTSX and -IBRS variants.
The separate variants will eventually be removed and become
aliases for these CPU versions.
Backports commit d86a708815c3bec0b934760e6bdab7eb647087b8 from qemu
Add support for registration of multiple versions of CPU models.
The existing CPU models will be registered with a "-v1" suffix.
The -noTSX, -IBRS, and -IBPB CPU model variants will become
versions of the original models in a separate patch, so
make sure we register no versions for them.
Backports commit dcafd1ef0af227ef87f7a6dec8fc66d7d2e2442d from qemu
The CPUID.1F as Intel V2 Extended Topology Enumeration Leaf would be
exposed if guests want to emulate multiple software-visible die within
each package. Per Intel's SDM, the 0x1f is a superset of 0xb, thus they
can be generated by almost same code as 0xb except die_offset setting.
If the number of dies per package is greater than 1, the cpuid_min_level
would be adjusted to 0x1f regardless of whether the host supports CPUID.1F.
Likewise, the CPUID.1F wouldn't be exposed if env->nr_dies < 2.
Backports commit a94e1428991f741e2c6636e7c8df7f8d1905d983 from qemu
In new sockets/dies/cores/threads model, the apicid of logical cpu could
imply die level info of guest cpu topology thus x86_apicid_from_cpu_idx()
need to be refactored with #dies value, so does apicid_*_offset().
To keep semantic compatibility, the legacy pkg_offset which helps to
generate CPUIDs such as 0x3 for L3 cache should be mapping to die_offset.
Backports commit d65af288a84d8bf8c27e55d45545f52f016c08a7 from qemu
The field die_id (default as 0) and has_die_id are introduced to X86CPU.
Following the legacy smp check rules, the die_id validity is added to
the same contexts as leagcy smp variables such as hmp_hotpluggable_cpus(),
machine_set_cpu_numa_node(), cpu_slot_to_string() and pc_cpu_pre_plug().
Backports relevant bits from 176d2cda0dee9f4f78f604ad72d6a111e8e38f3b
from qemu
The die-level as the first PC-specific cpu topology is added to the leagcy
cpu topology model, which has one die per package implicitly and only the
numbers of sockets/cores/threads are configurable.
In the new model with die-level support, the total number of logical
processors (including offline) on board will be calculated as:
\#cpus = #sockets * #dies * #cores * #threads
and considering compatibility, the default value for #dies would be
initialized to one in x86_cpu_initfn() and pc_machine_initfn().
Backports commit c26ae610811e8d52f4fc73e3ae0a8bc4a24d6763 from qemu
Coverity points out (CID 1402195) that the loop in trans_VMOV_imm_dp()
that iterates over the destination registers in a short-vector VMOV
accidentally throws away the returned updated register number
from vfp_advance_dreg(). Add the missing assignment. (We got this
correct in trans_VMOV_imm_sp().)
Backports commit 89a11ff756410aecb87d2c774df6e45dbf4105c1 from qemu
Thumb instructions in an IT block are set up to be conditionally
executed depending on a set of condition bits encoded into the IT
bits of the CPSR/XPSR. The architecture specifies that if the
condition bits are 0b1111 this means "always execute" (like 0b1110),
not "never execute"; we were treating it as "never execute". (See
the ConditionHolds() pseudocode in both the A-profile and M-profile
Arm ARM.)
This is a bit of an obscure corner case, because the only legal
way to get to an 0b1111 set of condbits is to do an exception
return which sets the XPSR/CPSR up that way. An IT instruction
which encodes a condition sequence that would include an 0b1111 is
UNPREDICTABLE, and for v8A the CONSTRAINED UNPREDICTABLE choices
for such an IT insn are to NOP, UNDEF, or treat 0b1111 like 0b1110.
Add a comment noting that we take the latter option.
Backports commit 5529de1e5512c05276825fa8b922147663fd6eac from qemu
In the various helper functions for v7M/v8M instructions, use
the _ra versions of cpu_stl_data() and friends. Otherwise we
may get wrong behaviour or an assert() due to not being able
to locate the TB if there is an exception on the memory access
or if it performs an IO operation when in icount mode
Backports commit 2884fbb60412049ec92389039ae716b32057382e from qemu
In preparation for supporting TCG disablement on ARM, we move most
of TCG related v7m/v8m helpers and APIs into their own file.
Note: It is easier to review this commit using the 'histogram'
diff algorithm:
$ git diff --diff-algorithm=histogram ...
or
$ git diff --histogram ...
Backports commit 7aab5a8c8bb525ea390b4ebc17ab82c0835cfdb6 from qemu
Semihosting hooks either SVC or HLT instructions, and inside KVM
both of those go to EL1, ie to the guest, and can't be trapped to
KVM.
Let check_for_semihosting() return False when not running on TCG.
backports commit 91f78c58da9ba78c8ed00f5d822b701765be8499 from qemu
This prevents a load reservation from being placed in one context/process,
then being used in another, resulting in an SC succeeding incorrectly and
breaking atomics.
Backports commit c13b169f1a3dd158d6c75727cdc388f95988db39 from qemu
The various CSR instructions have been split out of the base ISA as part
of the ratification process. This patch adds a Zicsr argument, which
disables all the CSR instructions.
Backports commit 591bddea8d874e1500921de0353818e5586618f5 from qemu
fence.i has been split out of the base ISA as part of the ratification
process. This patch adds a Zifencei argument, which disables the
fence.i instruction.
Backports commit 50fba816cd226001bec3e495c39879deb2fa5432 from qemu
Set the priv spec version 1.11.0 as the default and allow selecting it
via the command line.
Backports commit e3147506b02edcdd7c14ebb41a10fcc3027dcc5c from qemu
1.11 defines mcountinhibit, which has the same numeric CSR value as
mucounteren from 1.09.1 but has different semantics. This patch enables
the CSR for 1.11-based targets, which is trivial to implement because
the counters in QEMU never tick (legal according to the spec).
Backports commit 747a43e818dc36bd50ef98c2b11a7c31ceb810fa from qemu
Restructure the deprecated CPUs to make it clear in the code that these
are depreated. They are already marked as deprecated in
qemu-deprecated.texi. There are no functional changes.
Backports commit c1fb65e63cfca4506a14b084afd0eca2dc464fe8 from qemu
The current implementation returns 1 (PMP check success) if the address is in
range even if the PMP entry is off. This is a bug.
For example, if there is a PMP check in S-Mode which is in range, but its PMP
entry is off, this will succeed, which it should not.
The patch fixes this bug by only checking the PMP permissions if the address is
in range and its corresponding PMP entry it not off. Otherwise, it will keep
the ret = -1 which will be checked and handled correctly at the end of the
function.
Backports commit f8162068f18f2f264a0355938784f54089234211 from qemu
The PMP should be checked when doing a page table walk, and report access
fault exception if the to-be-read PTE failed the PMP check.
Backports commit 1f447aec787bfbbd078afccae44fc4c92acb4fed from qemu
The current PMP check function checks for env->priv which is not the effective
memory privilege mode.
For example, mstatus.MPRV could be set while executing in M-Mode, and in that
case the privilege mode for the PMP check should be S-Mode rather than M-Mode
(in env->priv) if mstatus.MPP == PRV_S.
This patch passes the effective memory privilege mode to the PMP check.
Functions that call the PMP check should pass the correct memory privilege mode
after reading mstatus' MPRV/MPP or hstatus.SPRV (if Hypervisor mode exists).
Backports commit cc0fdb298517ce56c770803447f8b02a90271152 from qemu
Section 3.6 in RISC-V v1.10 privilege specification states that PMP violations
report "access exceptions." The current PMP implementation has
a bug which wrongly reports "page exceptions" on PMP violations.
This patch fixes this bug by reporting the correct PMP access exceptions
trap values.
Backports commit 635b0b0ea39a13d1a3df932452e5728aebbb3f6e from qemu
The current implementation unnecessarily checks for PMP even if MMU translation
failed. This may trigger a wrong PMP access exception instead of
a page exception.
For example, the very first instruction fetched after the first satp write in
S-Mode will trigger a PMP access fault instead of an instruction fetch page
fault.
This patch prioritises MMU exceptions over PMP exceptions and only checks for
PMP if MMU translation succeeds. This patch is required for future commits
that properly report PMP exception violations if PTW succeeds.
Backports commit e0f8fa72deba7ac7a7ae06ba25e6498aaad93ace from qemu
