Am 28.02.2015 um 22:24 schrieb Mike Frysinger: > when running strace tests, we noticed that si_addr appears to be wrong. the > attached test shows the problem -- si_addr isn't set to the faulting address. > > i hacked arch/s390/mm/fault.c:do_sigsegv to load regs->psw.addr (sans mask), > and it worked for insn based crashes. but obviously that doesn't work for > data based ones. i'm not familiar with how regs->int_parm_long works though, > so maybe it's supposed to be loaded indirectly. the use of __FAIL_ADDR_MASK > blindly is most certainly incorrect ... > > whatever the fix, do_sigbus probably needs it too. The problem is that all faults on s390 give the address only on page granularity (HW-wise) e.g. if you use 0x123456 as fail address you get si_addr == 0x123000 > > on x86_64, both work: > $ gcc test.c -O3 > $ ./a.out > data crash > received signal 11 > si_addr 0xa0 > crasher 0xa0 > PASS > $ ./a.out asdf > text crash > received signal 11 > si_addr 0xa0 > crasher 0xa0 > PASS > > on s390 both fail: > $ gcc test.c -O3 > $ ./a.out > data crash > received signal 11 > si_addr (nil) > crasher 0xa0 > FAIL > $ ./a.out asdf > text crash > received signal 11 > si_addr (nil) > crasher 0xa0 > FAIL > > -mike > -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
