diff options
| author | Christian Krinitsin <mail@krinitsin.com> | 2025-06-30 12:24:58 +0000 |
|---|---|---|
| committer | Christian Krinitsin <mail@krinitsin.com> | 2025-06-30 12:27:06 +0000 |
| commit | 33606b41d35115f887ea688b1a16f2ff85bf2fe4 (patch) | |
| tree | 406b2c7b19a087ba437c68f3dbf0b589fa1d6150 /results/scraper/launchpad-without-comments/1776096 | |
| parent | adedf8771bc4de3113041ca21bd4d0d1c0014b6a (diff) | |
| download | emulator-bug-study-33606b41d35115f887ea688b1a16f2ff85bf2fe4.tar.gz emulator-bug-study-33606b41d35115f887ea688b1a16f2ff85bf2fe4.zip | |
add launchpad bug reports without comments
Diffstat (limited to 'results/scraper/launchpad-without-comments/1776096')
| -rw-r--r-- | results/scraper/launchpad-without-comments/1776096 | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/results/scraper/launchpad-without-comments/1776096 b/results/scraper/launchpad-without-comments/1776096 new file mode 100644 index 00000000..7c39305c --- /dev/null +++ b/results/scraper/launchpad-without-comments/1776096 @@ -0,0 +1,60 @@ +qemu 2.12.0 qemu-system-ppc illegal instruction on ppc64le, crashes emulator + +% uname -a +Linux tim.floodgap.com 4.16.14-300.fc28.ppc64le #1 SMP Tue Jun 5 15:59:48 UTC 2018 ppc64le ppc64le ppc64le GNU/Linux + +STR: +Start QEMU and boot Mac OS X 10.4.11. +Download the current version of TenFourFox (I used G3 so that AltiVec was not a confounder). +Try to start TenFourFox in safe mode (hold down Option as you double-click while the icon bounces in the Dock). + +Expected: +TenFourFox starts. + +Actual: +The entire emulator exits with an illegal instruction error. + +Trace of session (including some disassembly so you can see where TCG went wrong): + +tim:/home/spectre/src/qemu-2.12.0/ppc-softmmu/% gdb --args ./qemu-system-ppc -M mac99,accel=tcg -m 2048 -prom-env boot-args=-v -boot c -drive file=tigerhd.img,format=raw,cache=none -netdev user,id=mynet0 -device usb-net,netdev=mynet0 -usb -device usb-tablet + +GNU gdb (GDB) Fedora 8.1-15.fc28 +[...] +Reading symbols from ./qemu-system-ppc...done. +(gdb) run +[...] + +Thread 6 "qemu-system-ppc" received signal SIGSEGV, Segmentation fault. +[Switching to Thread 0x7ffff242ea30 (LWP 7017)] +0xfffffffffffffffc in ?? () +#0 0xfffffffffffffffc in () +#1 0x00007fffd4edec00 in code_gen_buffer () +#2 0x00000000100c9e20 in cpu_tb_exec (itb=<optimized out>, cpu=<optimized out>) at /home/spectre/src/qemu-2.12.0/accel/tcg/cpu-exec.c:169 +#3 0x00000000100c9e20 in cpu_loop_exec_tb (tb_exit=<synthetic pointer>, last_tb=<synthetic pointer>, tb=<optimized out>, cpu=<optimized out>) + at /home/spectre/src/qemu-2.12.0/accel/tcg/cpu-exec.c:626 +#4 0x00000000100c9e20 in cpu_exec (cpu=<optimized out>) + at /home/spectre/src/qemu-2.12.0/accel/tcg/cpu-exec.c:734 +#5 0x000000001007decc in tcg_cpu_exec (cpu=0x11774e10) + at /home/spectre/src/qemu-2.12.0/cpus.c:1362 +(gdb) disas 0x00007fffd4edebf0, 0x00007fffd4edec10 +Dump of assembler code from 0x7fffd4edebf0 to 0x7fffd4edec10: + 0x00007fffd4edebf0 <code_gen_buffer+284027700>: addi r0,r4,3 + 0x00007fffd4edebf4 <code_gen_buffer+284027704>: rlwinm r0,r0,0,0,19 + 0x00007fffd4edebf8 <code_gen_buffer+284027708>: cmplw cr7,r0,r12 + 0x00007fffd4edebfc <code_gen_buffer+284027712>: bnel cr7,0x7fffd4ed8b64 <code_gen_buffer+284002984> + 0x00007fffd4edec00 <code_gen_buffer+284027716>: lwbrx r14,r3,r4 + 0x00007fffd4edec04 <code_gen_buffer+284027720>: stw r14,40(r27) + 0x00007fffd4edec08 <code_gen_buffer+284027724>: clrldi r4,r14,32 + 0x00007fffd4edec0c <code_gen_buffer+284027728>: rlwinm r3,r4,25,19,26 +End of assembler dump. +(gdb) disas 0x7fffd4ed8b60, 0x7fffd4ed8b70 +Dump of assembler code from 0x7fffd4ed8b60 to 0x7fffd4ed8b70: + 0x00007fffd4ed8b60 <code_gen_buffer+284002980>: bctrl + 0x00007fffd4ed8b64 <code_gen_buffer+284002984>: mtctr r3 + 0x00007fffd4ed8b68 <code_gen_buffer+284002988>: mr r31,r3 + 0x00007fffd4ed8b6c <code_gen_buffer+284002992>: li r3,0 +End of assembler dump. +(gdb) i reg ctr +ctr 0xffffffffffffffff 18446744073709551615 + +It appears that the branch at 0x00007fffd4edebfc caused a jump back (a return?) through CTR, but CTR has -1 in it, hence setting PC to 0xfffffffffffffffc. I am not sure how to debug this further. \ No newline at end of file |