Recognise the R5900, which reports itself as MIPS III, as a 64-bit CPU
supporting the n32 ABI.
Signed-off-by: Fredrik Noring <noring@nocrew.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <5bea109f0c140da6a821aa7f9705d4b3717e86dc.1541701393.git.noring@nocrew.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
These were defined for other platforms but mistakenly left out of mips
and generic, so this commit adds them to the places missing. Then it
makes them be translated in getsockopt.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210204153925.2030606-1-Jason@zx2c4.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The sizeof(struct ifreq) is 40 for 64 bit and 32 for 32 bit architectures.
This structure contains a union of other structures, of which struct ifmap
is the biggest for 64 bit architectures. Calling ioclt(…, SIOCGIFCONF, …)
fills a struct sockaddr of that union, and do_ioctl_ifconf() only considered
that struct sockaddr for the size of the union, which has the same size as
struct ifmap on 32 bit architectures. So do_ioctl_ifconf() assumed a wrong
size of 32 for struct ifreq instead of the correct size of 40 on 64 bit
architectures.
The fix makes do_ioctl_ifconf() handle struct ifmap as the biggest part of
the union, treating struct ifreq with the correct size.
Signed-off-by: Stefan <stefan-guix@vodafonemail.de>
Message-Id: <60AA0765-53DD-43D1-A3D2-75F1778526F6@vodafonemail.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
If mremap() is called without the MREMAP_MAYMOVE flag with a start address
just before the end of memory (reserved_va) where new_size would exceed
it (and GUEST_ADDR_MAX), the assert(end - 1 <= GUEST_ADDR_MAX) in
page_set_flags() would trigger.
Add an extra guard to the guest_range_valid() checks to prevent this and
avoid asserting binaries when reserved_va is set.
This meant a bug I was seeing locally now gives the same behaviour
regardless of whether reserved_va is set or not.
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <70c46e7b999bafbb01d54bfafd44b420d0b782e9.camel@linuxfoundation.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Some ELF binaries encode the .bss section as an extension of the data
ones by setting the segment p_memsz > p_filesz. Some other binaries take
a different route and encode it as a stand-alone PT_LOAD segment with
p_filesz = 0 and p_memsz > 0.
Both the encodings are actually correct per ELF specification but the
ELF loader had some troubles in handling the former: with the old logic
it was very likely to get Qemu to crash in zero_bss when trying to
access unmapped memory.
zero_bss isn't meant to allocate whole zero-filled segments but to
"complete" a previously mapped segment with the needed zero bits.
The fix is pretty simple, if the segment is completely zero-filled we
simply allocate one or more pages (according to p_memsz) and avoid
calling zero_bss altogether.
Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
Message-Id: <c9106487-dc4d-120a-bd48-665b3c617287@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
On the hppa target userspace binaries may call signalfd4() and
eventfd2() with an old TARGET_O_NONBLOCK value of 000200004 instead of
000200000 for the "mask" syscall parameter, in which case the current
emulation doesn't handle the translation to the native O_NONBLOCK value
correctly.
The 0x04 bit is not masked out before the new O_NONBLOCK bit is set and
as such when calling the native syscall errors out with EINVAL.
Fix this by introducing TARGET_O_NONBLOCK_MASK which is used to mask off
all possible bits. This define defaults to TARGET_O_NONBLOCK when not
defined otherwise, so for all other targets the implementation will
behave as before.
This patch needs to be applied on top of my previous two patches.
Bug was found and patch was verified by using qemu-hppa as debian buildd
server on x86_64.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210210061214.GA221322@ls3530.fritz.box>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Historically the parisc linux port tried to be compatible with HP-UX
userspace and as such defined the O_NONBLOCK constant to 0200004 to
emulate separate NDELAY & NONBLOCK values.
Since parisc was the only Linux platform which had two bits set, this
produced various userspace issues. Finally it was decided to drop the
(never completed) HP-UX compatibilty, which is why O_NONBLOCK was
changed upstream to only have one bit set in future with this commit:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=75ae04206a4d0e4f541c1d692b7febd1c0fdb814
This patch simply adjusts the value for qemu-user too.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210201220551.GA8015@ls3530.fritz.box>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The hppa and alpha targets miss the #define of the TARGET___O_TMPFILE
and as such fail to run a trivial symlink command like
ln -s /bin/bash /tmp
which results in an -EINVAL return code.
Adding the define fixes the problem.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210201155922.GA18291@ls3530.fritz.box>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
When mapping the host waitid status to the target status we previously
just used decoding information in the status value. This doesn't follow
what the waitid documentation describes, which instead suggests using
the si_code value for the decoding. This results in the incorrect values
seen when calling waitid. This is especially apparent on RV32 where all
wait calls use waitid (see the bug case).
This patch just passes the waitid status directly back to the guest.
Buglink: https://bugs.launchpad.net/qemu/+bug/1906193
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Andreas K. Hüttel <dilfridge@gentoo.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <1fb2d56aa23a81f4473e638abe9e2d78c09a3d5b.1611080607.git.alistair.francis@wdc.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
64-bit MIPS targets lost setup_frame() during the refactor in commit
8949bef18b. Restore it declaring TARGET_ARCH_HAS_SETUP_FRAME, to be
able to build the o32 ABI target.
Fixes: 8949bef18b ("linux-user: move mips/mips64 signal.c parts to mips directory")
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20201119161710.1985083-2-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This will allow us to centralize the registration of
the cpus.c module accelerator operations (in accel/accel-softmmu.c),
and trigger it automatically using object hierarchy lookup from the
new accel_init_interfaces() initialization step, depending just on
which accelerators are available in the code.
Rename all tcg-cpus.c, kvm-cpus.c, etc to tcg-accel-ops.c,
kvm-accel-ops.c, etc, matching the object type names.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20210204163931.7358-18-cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These lock types are unsupported by Linux since v2.2[0][1] and
always return EINVAL (except on SPARC up until v2.6, which just
warned).
musl libc does not define these constants, so just remove them from
the translation cases.
[0] https://github.com/mpe/linux-fullhistory/blob/v2.2.0/fs/locks.c#L322-L324
[1] https://github.com/mpe/linux-fullhistory/blob/v2.2.0/fs/locks.c#L429-L445
Signed-off-by: Michael Forney <mforney@mforney.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210114223602.9004-1-mforney@mforney.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
SOL_UDP manipulate options at UDP level. All six options currently defined
in linux source include/uapi/linux/udp.h take integer values.
Signed-off-by: Shu-Chun Weng <scw@google.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20201218193213.3566856-3-scw@google.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Also reorder blocks so that they are all in the same order everywhere.
Signed-off-by: Shu-Chun Weng <scw@google.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20201218193213.3566856-2-scw@google.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This could made testing more easier and ARM/AArch64 has supported on
their linux user mode too, so I think it should be reasonable.
Verified GCC testsuite with newlib/semihosting.
Signed-off-by: Kito Cheng <kito.cheng@sifive.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210107170717.2098982-7-keithp@keithp.com>
Message-Id: <20210108224256.2321-18-alex.bennee@linaro.org>
Adapt the arm semihosting support code for RISCV. This implementation
is based on the standard for RISC-V semihosting version 0.2 as
documented in
https://github.com/riscv/riscv-semihosting-spec/releases/tag/0.2
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20210107170717.2098982-6-keithp@keithp.com>
Message-Id: <20210108224256.2321-17-alex.bennee@linaro.org>
The public API is now defined in
hw/semihosting/common-semi.h. do_common_semihosting takes CPUState *
instead of CPUARMState *. All internal functions have been renamed
common_semi_ instead of arm_semi_ or arm_. Aside from the API change,
there are no functional changes in this patch.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20210107170717.2098982-3-keithp@keithp.com>
Message-Id: <20210108224256.2321-14-alex.bennee@linaro.org>
This commit renames two files which provide ARM semihosting support so
that they can be shared by other architectures:
1. target/arm/arm-semi.c -> hw/semihosting/common-semi.c
2. linux-user/arm/semihost.c -> linux-user/semihost.c
The build system was modified use a new config variable,
CONFIG_ARM_COMPATIBLE_SEMIHOSTING, which has been added to the ARM
softmmu and linux-user default configs. The contents of the source
files has not been changed in this patch.
Signed-off-by: Keith Packard <keithp@keithp.com>
[AJB: rename arm-compat-semi, select SEMIHOSTING]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210107170717.2098982-2-keithp@keithp.com>
Message-Id: <20210108224256.2321-13-alex.bennee@linaro.org>
gdb_exit() has never needed anything from env and I doubt we are going
to start now.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210108224256.2321-8-alex.bennee@linaro.org>
Extract FPU specific helpers from "internal.h" to "fpu_helper.h".
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201120210844.2625602-2-f4bug@amsat.org>
The MIPS ISA release 6 is common to 32/64-bit CPUs.
To avoid holes in the insn_flags type, update the
definition with the next available bit.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210104221154.3127610-16-f4bug@amsat.org>
The MIPS ISA release 2 is common to 32/64-bit CPUs.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210104221154.3127610-13-f4bug@amsat.org>
Use the single ISA_MIPS32R6 definition to check if the Release 6
ISA is supported, whether the CPU support 32/64-bit.
For now we keep '32' in the definition name, we will rename it
as ISA_MIPS_R6 in few commits.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210104221154.3127610-11-f4bug@amsat.org>
Use the single ISA_MIPS32R2 definition to check if the Release 2
ISA is supported, whether the CPU support 32/64-bit.
For now we keep '32' in the definition name, we will rename it
as ISA_MIPS_R2 in few commits.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210104221154.3127610-8-f4bug@amsat.org>
Plumb the value through to alloc_code_gen_buffer. This is not
supported by any os or tcg backend, so for now enabling it will
result in an error.
Reviewed-by: Joelle van Dyne <j@getutm.app>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This fixes the build for older ppc64 kernel headers.
Fixes: 6addf06a3c
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Correctly implement save/restore of the tstate field in
sparc64_get_context() and sparc64_set_context():
* Don't use the CWP value from the guest in set_context
* Construct and save a tstate value rather than leaving
it as zero in get_context
To do this we factor out the "calculate TSTATE value from CPU state"
code from sparc_cpu_do_interrupt() into its own sparc64_tstate()
function; that in turn requires us to move some of the function
prototypes out from inside a CPU_NO_IO_DEFS ifdef guard.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-5-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The kernel does not restore the g7 register in sparc64_set_context();
neither should we. (We still save it in sparc64_get_context().)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-4-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Unlike the kernel macros, our __get_user() and __put_user() do not
return a failure code. Kernel code typically has a style of
err |= __get_user(...); err |= __get_user(...);
and then checking err at the end. In sparc64_get_context() our
version of the code dropped the accumulating into err but left the
"if (err) goto do_sigsegv" checks, which will never be taken. Delete
unnecessary if()s.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-3-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The handling of the FPU state in sparc64_get_context() and
sparc64_set_context() is not the same as what the kernel actually
does: we unconditionally read and write the FP registers and the
FSR, GSR and FPRS, but the kernel logic is more complicated:
* in get_context the kernel has code for saving FPU registers,
but it is hidden inside an "if (fenab) condition and the
fenab flag is always set to 0 (inside an "#if 1" which has
been in the kernel for over 15 years). So the effect is that
the FPU state part is always written as zeroes.
* in set_context the kernel looks at the fenab field in the
structure from the guest, and only restores the state if
it is set; it also looks at the structure's FPRS to see
whether either the upper or lower or both halves of the
register file have valid data.
Bring our implementations into line with the kernel:
* in get_context:
- clear the entire target_ucontext at the top of the
function (as the kernel does)
- then don't write the FPU state, so those fields remain zero
- this fixes Coverity issue CID 1432305 by deleting the code
it was complaining about
* in set_context:
- check the fenab and the fpsr to decide which parts of
the FPU data to restore, if any
- instead of setting the FPU registers by doing two
32-bit loads and filling in the .upper and .lower parts
of the CPU_Double union separately, just do a 64-bit
load of the whole register at once. This fixes Coverity
issue CID 1432303 because we now access the dregs[] part
of the mcfpu_fregs union rather than the sregs[] part
(which is not large enough to actually cover the whole of
the data, so we were accessing off the end of sregs[])
We change both functions in a single commit to avoid potentially
breaking bisection.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201106152738.26026-2-peter.maydell@linaro.org>
[lv: fix FPRS_DU loop s/31/32/]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The three options handling `struct sock_fprog` (TUNATTACHFILTER,
TUNDETACHFILTER, and TUNGETFILTER) are not implemented. Linux kernel
keeps a user space pointer in them which we cannot correctly handle.
Signed-off-by: Josh Kunz <jkz@google.com>
Signed-off-by: Shu-Chun Weng <scw@google.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200929014801.655524-1-scw@google.com>
[lv: use 0 size in unlock_user()]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <mvm361eer3n.fsf@suse.de>
[lv: copy back offset only if there is no error]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Userland ELF binaries using Loongson SIMD instructions have the
HWCAP_LOONGSON_MMI bit set [1].
Binaries compiled for Loongson 3A [2] have the HWCAP_LOONGSON_EXT
bit set for the LQ / SQ instructions.
[1] commit 8e2d5831e4 ("target/mips: Legalize Loongson insn flags")
[2] commit af868995e1 ("target/mips: Add Loongson-3 CPU definition")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-7-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
ISA features are usually denoted in read-only bits from
CPU registers. Add the GET_FEATURE_REG_EQU() macro which
checks if a CPU register has bits set to a specific value.
Use the macro to check the 'Architecture Revision' level
of the Config0 register, which is '2' when the Release 6
ISA is implemented.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-5-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
ISA features are usually denoted in read-only bits from
CPU registers. Add the GET_FEATURE_REG_SET() macro which
checks if a CPU register has bits set.
Use the macro to check for MSA (which sets the MSAP bit of
the Config3 register when the ASE implementation is present).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-4-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
We want to add macros similar to GET_FEATURE().
As this one use the 'insn_flags' field, rename it
GET_FEATURE_INSN().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-3-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
As we are going to add more macros, keep the function body clear.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-2-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
If mremap succeeds, an additional check is performed to ensure that the
new address range fits into the target address space. This check was
previously perfomed in host address space, with the upper bound fixed to
abi_ulong.
This patch replaces the static check with a call to `guest_range_valid`,
performing the range check against the actual size of the target address
space. It also moves the corresponding block to prevent it from being
called incorrectly when the mapping itself fails.
Signed-off-by: Tobias Koch <tobias.koch@nonterra.com>
Message-Id: <20201028213833.26592-1-tobias.koch@nonterra.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
QEMU requires Clang or GCC, that define and support __GNUC__ extensions.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201210134752.780923-13-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
qemu_finish_machine_init currently can only exit QEMU if it fails.
Prepare for giving it proper error propagation, and possibly for
adding a plugin_add monitor command that calls an accelerator
method.
While at it, make all errors from plugin_load look the same.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This check can be done in a much shorter way in meson.build. And while
we're at it, rename the #define to HAVE_BTRFS_H to match the other
HAVE_someheader_H symbols that we already have.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201118171052.308191-7-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This check can be done in a much shorter way in meson.build. And while
we're at it, rename the #define to HAVE_SYS_KCOV_H to match the other
HAVE_someheader_H symbols that we already have.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201118171052.308191-6-thuth@redhat.com>
[lv: s/signal/kcov/]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The Linux kernel doesn't use the official bkpt insn for breakpoints;
instead it uses three instructions in the guaranteed-to-UNDEF space,
and generates SIGTRAP for these rather than the SIGILL that most
UNDEF insns generate:
https://elixir.bootlin.com/linux/v5.9.8/source/arch/arm/kernel/ptrace.c#L197
Make QEMU treat these insns specially too. The main benefit of this
is that if you're running a debugger on a guest program that runs
into a GCC __builtin_trap() or LLVM "trap because execution should
never reach here" then you'll get the expected signal rather than a
SIGILL.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201117155634.6924-1-peter.maydell@linaro.org
