On Fri, Sep 27, 2013 at 11:36 PM, Paolo Bonzini <[email protected]> wrote: > Il 27/09/2013 20:29, Max Filippov ha scritto: >> Hi, >> >> I'm getting said assertion failure debugging linux userspace >> application through the qemu gdbstub. The backtrace looks like this: >> >> qemu-system-xtensa: include/qemu/int128.h:22: int128_get64: Assertion >> `!a.hi' failed. >> >> Program received signal SIGABRT, Aborted. >> [Switching to Thread 0x7ffff7fe8880 (LWP 15378)] >> 0x00007ffff639e285 in raise () from /lib64/libc.so.6 >> (gdb) bt >> #0 0x00007ffff639e285 in raise () from /lib64/libc.so.6 >> #1 0x00007ffff639fb9b in abort () from /lib64/libc.so.6 >> #2 0x00007ffff6396e9e in __assert_fail_base () from /lib64/libc.so.6 >> #3 0x00007ffff6396f42 in __assert_fail () from /lib64/libc.so.6 >> #4 0x00005555556eea6a in int128_get64 (a=...) at include/qemu/int128.h:22 >> #5 0x00005555556efb81 in address_space_translate_internal >> (d=0x7fffdc01c920, addr=18446744069448138751, xlat=0x7fffffffa4b0, >> plen=0x7fffffffa540, >> resolve_subpage=true) at exec.c:264 >> #6 0x00005555556efc03 in address_space_translate (as=0x555555e8d100, >> addr=18446744069448138751, xlat=0x7fffffffa538, plen=0x7fffffffa540, >> is_write=false) at exec.c:278 >> #7 0x0000555555757dd3 in tb_invalidate_phys_addr >> (addr=18446744073709551615) at translate-all.c:1373 >> #8 0x00005555556f00f2 in breakpoint_invalidate (cpu=0x555555f1df80, >> pc=537189728) at exec.c:413 >> #9 0x00005555556f0725 in cpu_breakpoint_remove_by_ref (env=0x555555f1e0b8, >> breakpoint=0x555555f4bc20) at exec.c:557 >> #10 0x00005555556f0649 in cpu_breakpoint_remove (env=0x555555f1e0b8, >> pc=537189728, flags=16) at exec.c:541 >> #11 0x000055555570c13b in gdb_breakpoint_remove (addr=537189728, len=2, >> type=0) at gdbstub.c:691 >> #12 0x000055555570d031 in gdb_handle_packet (s=0x555555f38100, >> line_buf=0x555555f3811c "z0,2004dd60,2") at gdbstub.c:991 >> #13 0x000055555570e45c in gdb_read_byte (s=0x555555f38100, ch=56) at >> gdbstub.c:1405 >> #14 0x000055555570e5b0 in gdb_chr_receive (opaque=0x0, buf=0x7fffffffc810 >> "$z0,2004dd60,2#289process+;qRelocInsn+#2a+=\366\377\177", size=17) at >> gdbstub.c:1623 >> #15 0x000055555567d463 in qemu_chr_be_write (s=0x555555f0c640, >> buf=0x7fffffffc810 >> "$z0,2004dd60,2#289process+;qRelocInsn+#2a+=\366\377\177", len=17) >> at qemu-char.c:165 >> #16 0x000055555568185b in tcp_chr_read (chan=0x555555f0c050, cond=G_IO_IN, >> opaque=0x555555f0c640) at qemu-char.c:2505 >> #17 0x00007ffff76f1f3d in g_main_context_dispatch () from >> /lib64/libglib-2.0.so.0 >> #18 0x000055555564a301 in glib_pollfds_poll () at main-loop.c:189 >> #19 0x000055555564a3f5 in os_host_main_loop_wait (timeout=-1) at >> main-loop.c:234 >> #20 0x000055555564a4c8 in main_loop_wait (nonblocking=0) at main-loop.c:483 >> #21 0x00005555556d9c04 in main_loop () at vl.c:2016 >> #22 0x00005555556e0e6b in main (argc=20, argv=0x7fffffffdd88, >> envp=0x7fffffffde30) at vl.c:4361 >> >> >> breakpoint_invalidate couldn't map breakpoint's virtual address, >> and get_phys_page_debug returned -1: >> >> (gdb) f 7 >> #7 0x0000555555757dd3 in tb_invalidate_phys_addr >> (addr=18446744073709551615) at translate-all.c:1373 >> 1373 mr = address_space_translate(&address_space_memory, addr, &addr, >> &l, false); >> (gdb) p/x addr >> $2 = 0xffffffffffffffff >> >> >> Later address_space_translate_internal found a section that didn't actually >> contain the addr and made a diff with non-zero .hi: >> >> (gdb) f 5 >> #5 0x00005555556efb81 in address_space_translate_internal >> (d=0x7fffdc01c920, addr=18446744069448138751, xlat=0x7fffffffa4b0, >> plen=0x7fffffffa540, >> resolve_subpage=true) at exec.c:264 >> 264 *plen = int128_get64(int128_min(diff, int128_make64(*plen))); >> (gdb) p/x diff >> $4 = { >> lo = 0x100000001, >> hi = 0xffffffffffffffff >> } >> (gdb) p/x *section >> $6 = { >> mr = 0x555555f04b00, >> address_space = 0x555555e8d100, >> offset_within_region = 0x0, >> size = { >> lo = 0x2000000, >> hi = 0x0 >> }, >> offset_within_address_space = 0xfe000000, >> readonly = 0x0 >> } >> >> >> I'm not sure what's the proper fix, returning -1 for the failed >> get_phys_page_debug >> is common for 32-bit targets. The easiest seems to be checking the result of >> cpu_get_phys_page debug in the breakpoint_invalidate: >> >> --- >8 --- >> commit cb3f9f90688be062b8a1f12b116f3d48c7ded232 >> Author: Max Filippov <[email protected]> >> Date: Fri Sep 27 22:19:16 2013 +0400 >> >> exec: fix breakpoint_invalidate when pc may not be translated >> >> This fixes qemu abort with the following message: >> >> include/qemu/int128.h:22: int128_get64: Assertion `!a.hi' failed. >> >> which happens due to attempt to invalidate breakpoint by virtual address >> for which get_phys_page_debug couldn't find mapping. >> >> Signed-off-by: Max Filippov <[email protected]> >> >> diff --git a/exec.c b/exec.c >> index 26681ce..a7e284a 100644 >> --- a/exec.c >> +++ b/exec.c >> @@ -410,8 +410,10 @@ static void breakpoint_invalidate(CPUState *cpu, >> target_ulong pc) >> #else >> static void breakpoint_invalidate(CPUState *cpu, target_ulong pc) >> { >> - tb_invalidate_phys_addr(cpu_get_phys_page_debug(cpu, pc) | >> - (pc & ~TARGET_PAGE_MASK)); >> + hwaddr phys = cpu_get_phys_page_debug(cpu, pc); >> + if (phys != -1) { >> + tb_invalidate_phys_addr(phys | (pc & ~TARGET_PAGE_MASK)); >> + } >> } >> #endif >> #endif /* TARGET_HAS_ICE */ >> >> > > Yes, this makes sense. I'll queue it for 1.6.2 and 1.7.
Ping? Paolo, do you need this patch resent without scissors? -- Thanks. -- Max
