The alternate signal stack set up by the sigaltstack syscall is
supposed to be per-thread. We were incorrectly implementing it as
process-wide. This causes problems for guest binaries that rely on
this. Notably the Go runtime does, and so we were seeing crashes
caused by races where two guest threads might incorrectly both
execute on the same stack simultaneously.
Replace the global target_sigaltstack_used with a field
sigaltstack_used in the TaskState, and make all the references to the
old global instead get a pointer to the TaskState and use the field.
Fixes: https://bugs.launchpad.net/qemu/+bug/1696773
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20190725131645.19501-1-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
No code change, only move code from signal.c to
hppa/signal.c, except adding includes and
exporting setup_rt_frame().
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180424192635.6027-15-laurent@vivier.eu>
Create a signal-common.h for future use by these new files
and use it in the existing signal.c
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180424192635.6027-2-laurent@vivier.eu>
