qemu/stubs
Peter Maydell 5202861b20 semihosting: Allow optional use of semihosting from userspace
Currently our semihosting implementations generally prohibit use of
semihosting calls in system emulation from the guest userspace.  This
is a very long standing behaviour justified originally "to provide
some semblance of security" (since code with access to the
semihosting ABI can do things like read and write arbitrary files on
the host system).  However, it is sometimes useful to be able to run
trusted guest code which performs semihosting calls from guest
userspace, notably for test code.  Add a command line suboption to
the existing semihosting-config option group so that you can
explicitly opt in to semihosting from guest userspace with
 -semihosting-config userspace=on

(There is no equivalent option for the user-mode emulator, because
there by definition all code runs in userspace and has access to
semihosting already.)

This commit adds the infrastructure for the command line option and
adds a bool 'is_user' parameter to the function
semihosting_userspace_enabled() that target code can use to check
whether it should be permitting the semihosting call for userspace.
It mechanically makes all the callsites pass 'false', so they
continue checking "is semihosting enabled in general".  Subsequent
commits will make each target that implements semihosting honour the
userspace=on option by passing the correct value and removing
whatever "don't do this for userspace" checking they were doing by
hand.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220822141230.3658237-2-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-09-13 17:18:21 +01:00
..
bdrv-next-monitor-owned.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
blk-commit-all.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
blk-exp-close-all.c block: move block exports to libblockdev 2020-10-23 13:42:16 +01:00
blockdev-close-all-bdrv-states.c all: Clean up includes 2016-02-16 14:29:28 +00:00
change-state-handler.c sysemu: Split sysemu/runstate.h off sysemu/sysemu.h 2019-08-16 13:37:36 +02:00
cmos.c stubs/cmos: Use correct include 2020-09-01 09:10:58 +02:00
cpu-get-clock.c cpu-timers, icount: new modules 2020-10-05 16:41:22 +02:00
cpu-synchronize-state.c cpus: prepare new CpusAccel cpu accelerator interface 2020-10-05 16:41:22 +02:00
cpus-get-virtual-clock.c cpus: prepare new CpusAccel cpu accelerator interface 2020-10-05 16:41:22 +02:00
dump.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
error-printf.c Move error_printf_unless_qmp() with monitor unit 2022-04-21 17:09:09 +04:00
fdset.c monitor: simplify functions for getting a dup'd fdset entry 2020-09-16 10:33:48 +01:00
fw_cfg.c hw/nvram/fw_cfg: Add fw_cfg_arch_key_name() 2019-05-23 14:10:31 +02:00
gdbstub.c Clean up includes some more 2016-03-22 22:20:16 +01:00
get-vm-name.c include: move qemu_get_vm_name() to sysemu.h 2022-04-06 14:31:43 +02:00
icount.c replay: notify vCPU when BH is scheduled 2022-06-06 09:26:53 +02:00
io_uring.c stubs: add stubs for io_uring interface 2020-01-30 20:59:41 +00:00
iothread-lock-block.c main-loop.h: introduce qemu_in_main_thread() 2022-03-04 18:18:15 +01:00
iothread-lock.c async: the main AioContext is only "current" if under the BQL 2021-06-18 10:59:52 -05:00
is-daemonized.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
isa-bus.c stubs: add isa_create_simple 2020-07-06 17:01:11 +02:00
linux-aio.c linux-aio: properly bubble up errors from initialization 2018-06-27 13:06:34 +01:00
meson.build vfio-user: handle device interrupts 2022-06-15 16:43:42 +01:00
migr-blocker.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
module-opts.c modules: use modinfo for qemu opts load 2021-07-09 18:20:27 +02:00
monitor-core.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
monitor.c hmp: Fail gracefully if chardev is already in use 2020-03-06 17:21:28 +01:00
pci-bus.c stubs: add pci_create_simple 2020-07-06 17:01:11 +02:00
qdev.c qapi/qdev.json: add DEVICE_UNPLUG_GUEST_ERROR QAPI event 2021-09-30 12:25:51 +10:00
qemu-timer-notify-cb.c cpu-timers, icount: new modules 2020-10-05 16:41:22 +02:00
qmp-command-available.c remove preconfig state 2020-12-15 12:51:48 -05:00
qmp-quit.c chardev: don't exit() straight away on C-a x 2021-11-04 10:32:01 +00:00
qmp_memory_device.c qom/object: Move Object typedef to 'qemu/typedefs.h' 2020-06-10 12:09:36 -04:00
qtest.c cpu-timers, icount: new modules 2020-10-05 16:41:22 +02:00
ram-block.c util/vfio-helpers.c: Use ram_block_discard_disable() in qemu_vfio_open_pci() 2020-11-16 13:22:17 -05:00
ramfb.c Revert "hw/display/ramfb: initialize fw-config space with xres/ yres" 2020-05-18 15:42:34 +02:00
replay-tools.c stubs: update replay-tools to match replay.h types 2022-07-28 15:36:17 +02:00
replay.c replay: do not build if TCG is not available 2020-10-22 11:53:54 -04:00
runstate-check.c sysemu: Split sysemu/runstate.h off sysemu/sysemu.h 2019-08-16 13:37:36 +02:00
semihost.c semihosting: Allow optional use of semihosting from userspace 2022-09-13 17:18:21 +01:00
sysbus.c stubs: Clean up includes 2016-02-04 17:01:04 +00:00
target-get-monitor-def.c Clean up includes some more 2016-03-22 22:20:16 +01:00
target-monitor-defs.c Clean up includes some more 2016-03-22 22:20:16 +01:00
trace-control.c trace: remove global 'uint16 dstate[]' array 2016-10-12 09:35:54 +02:00
usb-dev-stub.c qapi: introduce x-query-usb QMP command 2021-11-02 15:55:14 +00:00
uuid.c qapi: Restrict query-uuid command to machine code 2020-09-29 15:41:35 +02:00
vfio-user-obj.c vfio-user: handle device interrupts 2022-06-15 16:43:42 +01:00
vm-stop.c sysemu: Split sysemu/runstate.h off sysemu/sysemu.h 2019-08-16 13:37:36 +02:00
vmgenid.c qapi: Restrict query-vm-generation-id command to machine code 2020-09-29 15:41:35 +02:00
vmstate.c cpu: Move CPUClass::vmsd to SysemuCPUOps 2021-05-26 15:33:59 -07:00
win32-kbd-hook.c ui/win32-kbd-hook: handle AltGr in a hook procedure 2020-05-19 09:06:44 +02:00
xen-hw-stub.c hw/i386/xen/xen-hvm: Inline xen_piix_pci_write_config_client() and remove it 2022-06-29 00:24:59 +02:00