Commit 7f4f0d9ea8 ("linux-user/arm: Implement __kernel_cmpxchg with host
atomics") switched to use qatomic_cmpxchg() to swap a word with the memory
content, but missed to endianess-swap the oldval and newval values when
emulating an armeb CPU, which expects words to be stored in big endian in
the guest memory.
The bug can be verified with qemu >= v7.0 on any little-endian host, when
starting the armeb binary of the upx program, which just hangs without
this patch.
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Reported-by: John Reiser <jreiser@BitWagon.com>
Closes: https://github.com/upx/upx/issues/687
Message-Id: <ZMQVnqY+F+5sTNFd@p100>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Perform the cleanup in the FIXME comment in common_semi_gdb_syscall.
Do not modify guest registers until the syscall is complete,
which in the gdbstub case is asynchronous.
In the synchronous non-gdbstub case, use common_semi_set_ret
to set the result. Merge set_swi_errno into common_semi_cb.
Rely on the latter for combined return value / errno setting.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This value is fully internal to qemu, and so is not a TARGET define.
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This value is fully internal to qemu, and so is not a TARGET define.
We use this as an extra marker for both host and target errno.
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Because of the complexity of setting ESR, re-use the existing
arm_cpu_do_unaligned_access function. This means we have to
handle the exception ourselves in cpu_loop, transforming it
to the appropriate signal.
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In the Arm target code, when the fpa11 emulation code tells us we
need to send the guest a SIGFPE, we do this with queue_signal(), but
we are using the wrong si_type, and we aren't setting the _sifields
union members corresponding to either the si_type we are using or the
si_type we should be using.
As the existing comment notes, the kernel code for this calls the old
send_sig() function to deliver the signal. This eventually results
in the kernel's signal handling code fabricating a siginfo_t with a
SI_KERNEL code and a zero pid and uid. For QEMU this means we need
to use QEMU_SI_KILL. We already have a function for that:
force_sig() sets up the whole target_siginfo_t the way we need it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210813131809.28655-4-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
qemu.h is included in various non-linux-user files (which
mostly want the TaskState struct and the functions for
doing usermode access to guest addresses like lock_user(),
unlock_user(), get_user*(), etc).
Split out the parts that are only used in linux-user itself
into a new user-internals.h. This leaves qemu.h with basically
three things:
* the definition of the TaskState struct
* the user-access functions and macros
* do_brk()
all of which are needed by code outside linux-user that
includes qemu.h.
The addition of all the extra #include lines was done with
sed -i '/include.*qemu\.h/a #include "user-internals.h"' $(git grep -l 'include.*qemu\.h' linux-user)
(and then undoing the change to fpa11.h).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210908154405.15417-8-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>