This is an interesting collection of different bugs: * s390x is missing masking operations, as you describe * ppc is passing the PC of the offending insn, not the data address, into si_addr * sparc fails to record the address of a data fault and so passes 0 into si_addr * sparc also isn't implementing rt_sigaction correctly and so the calls in your test program fail EINVAL (your test program doesn't check the return value from sigaction, so it ploughs ahead and makes the faulting data access with the SIG_DFL behaviour for SEGV, hence the uncaught SEGV).
I'm putting together some patches for these. ** Changed in: qemu Status: New => Confirmed -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1705118 Title: qemu user mode does not support catching SIGSEGV on some architectures Status in QEMU: Confirmed Bug description: The documentation <https://qemu.weilnetz.de/doc/qemu-doc.html#Features> says that qemu in user mode supports POSIX signal handling. Catching SIGSEGV according to POSIX, however, does not work on ppc, ppc64, ppc64le, s390x, sparc64. It does work, however, on aarch64, alpha, arm, hppa, m68k, mips, mips64, sh4. How to reproduce: The attached program runs fine (exits with code 0) on - real hardware Linux/PowerPC64 (in 32-bit and 64-bit mode), - real hardware Linux/PowerPC64LE, - qemu-system-s390x emulated Linux/s390x, - real hardware Linux/SPARC64. $ gcc -O -Wall testsigsegv.c; ./a.out; echo $? 0 For ppc: $ powerpc-linux-gnu-gcc-5 -O -Wall -static testsigsegv.c -o testsigsegv-ppc $ ~/inst-qemu/2.9.0/bin/qemu-ppc testsigsegv-ppc $ echo $? 3 For ppc64: $ powerpc64-linux-gnu-gcc-5 -O -Wall -static testsigsegv.c -o testsigsegv-ppc64 $ ~/inst-qemu/2.9.0/bin/qemu-ppc64 testsigsegv-ppc64 $ echo $? 3 For ppc64le: $ powerpc64le-linux-gnu-gcc-5 -O -Wall -static testsigsegv.c -o testsigsegv-ppc64le $ ~/inst-qemu/2.9.0/bin/qemu-ppc64le testsigsegv-ppc64le $ echo $? 3 For s390x: $ s390x-linux-gnu-gcc-5 -O -Wall -static testsigsegv.c -o testsigsegv-s390x $ ~/inst-qemu/2.9.0/bin/qemu-s390x testsigsegv-s390x $ echo $? 3 $ s390x-linux-gnu-gcc-5 -O -Wall -static testsigsegv.c -DAVOID_LINUX_S390X_COMPAT -o testsigsegv-s390x-a $ ~/inst-qemu/2.9.0/bin/qemu-s390x testsigsegv-s390x-a $ echo $? 0 So, the test fails here because the Linux/s390x kernel omits the least significant 12 bits of the fault address in the 'si_addr' field. But qemu-s390x is not compatible with the Linux/s390x behaviour: it puts the complete fault address in the 'si_addr' field. For sparc64: $ sparc64-linux-gnu-gcc-5 -O -Wall -static testsigsegv.c -o testsigsegv-sparc64 $ ~/inst-qemu/2.9.0/bin/qemu-sparc64 testsigsegv-sparc64 Segmentation fault (core dumped) To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1705118/+subscriptions