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| author | Christian Krinitsin <mail@krinitsin.com> | 2025-07-03 07:27:52 +0000 |
|---|---|---|
| committer | Christian Krinitsin <mail@krinitsin.com> | 2025-07-03 07:27:52 +0000 |
| commit | d0c85e36e4de67af628d54e9ab577cc3fad7796a (patch) | |
| tree | f8f784b0f04343b90516a338d6df81df3a85dfa2 /results/classifier/deepseek-2-tmp/output/debug/1857640 | |
| parent | 7f4364274750eb8cb39a3e7493132fca1c01232e (diff) | |
| download | emulator-bug-study-d0c85e36e4de67af628d54e9ab577cc3fad7796a.tar.gz emulator-bug-study-d0c85e36e4de67af628d54e9ab577cc3fad7796a.zip | |
add deepseek and gemma results
Diffstat (limited to 'results/classifier/deepseek-2-tmp/output/debug/1857640')
| -rw-r--r-- | results/classifier/deepseek-2-tmp/output/debug/1857640 | 132 |
1 files changed, 0 insertions, 132 deletions
diff --git a/results/classifier/deepseek-2-tmp/output/debug/1857640 b/results/classifier/deepseek-2-tmp/output/debug/1857640 deleted file mode 100644 index 4829cd72..00000000 --- a/results/classifier/deepseek-2-tmp/output/debug/1857640 +++ /dev/null @@ -1,132 +0,0 @@ - -qemu-system-i386 registers clobbered after gdb set due to k_gs_base bug in gdbstub - -Due to a bug in /target/i386/gdbstub.c, setting registers in gdb causes the ones following k_gs_base to get clobbered. - -I'm using qemu version 4.2.50 on an msys64 and start qemu's i386 with a gdb server. - -$ qemu-system-i386 -version -QEMU emulator version 4.2.50 (v4.2.0-363-gdd5b0f9549-dirty) -Copyright (c) 2003-2019 Fabrice Bellard and the QEMU Project developers - -$ qemu-system-i386 -gdb tcp::29096 -S -C:\msys64\usr\local\qemu-system-i386.exe: invalid accelerator kvm -C:\msys64\usr\local\qemu-system-i386.exe: falling back to tcg - - -I start a gdb client, connect to the server, display the register state, set k_gs_base, display the register state again, and notice an issue. (Setting other registers also clobbers the ones after k_gs_base). - -$ gdb -q -(gdb) target remote :29096 -... -(gdb) info regs -... -gs_base 0x0 0 -k_gs_base 0x0 0 -cr0 0x60000010 [ CD NW ET ] -cr2 0x0 0 -... -(gdb) set $k_gs_base = 0x41414141 -(gdb) info regs -... -gs_base 0x0 0 -k_gs_base 0x0 0 -cr0 0x41414151 [ CD WP ET PE ] -cr2 0x60000010 1610612752 -... - - -In the gdbstub code, I notice that the read and write functions are not symmetric for IDX_SEG_REGS + 8, which corresponds to k_gs_base. - -$ cat /usr/local/src/qemu-4.2.0/target/i386/gdbstub.c -... -int x86_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n) -{ -... - case IDX_SEG_REGS + 8: -#ifdef TARGET_X86_64 - if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { - return gdb_get_reg64(mem_buf, env->kernelgsbase); - } - return gdb_get_reg32(mem_buf, env->kernelgsbase); -#else - return gdb_get_reg32(mem_buf, 0); -#endif -... -} -... -int x86_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) -{ -... -#ifdef TARGET_X86_64 - case IDX_SEG_REGS + 8: - if (env->hflags & HF_CS64_MASK) { - env->kernelgsbase = ldq_p(mem_buf); - return 8; - } - env->kernelgsbase = ldl_p(mem_buf); - return 4; -#endif -... -} -... - - -I change the write function, rebuild, and verify that the issue is resolved. - -$ cat /usr/local/src/qemu-4.2.0/target/i386/gdbstub.c -int x86_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) -{ -... - case IDX_SEG_REGS + 8: -#ifdef TARGET_X86_64 - if (env->hflags & HF_CS64_MASK) { - env->kernelgsbase = ldq_p(mem_buf); - return 8; - } - env->kernelgsbase = ldl_p(mem_buf); - return 4; -#else - return 4; -#endif -... -} -... - -$ make -... -$ make install -... - -$ qemu-system-i386 -gdb tcp::29096 -S - -$ gdb -q -(gdb) target remote :29096 -... -(gdb) info regs -... -gs_base 0x0 0 -k_gs_base 0x0 0 -cr0 0x60000010 [ CD NW ET ] -cr2 0x0 0 -... -(gdb) set $k_gs_base = 0x41414141 -(gdb) info regs -... -gs_base 0x0 0 -k_gs_base 0x0 0 -cr0 0x60000010 [ CD NW ET ] -cr2 0x0 0 -... - - -I'll submit the patch below. - -$ diff gdbstub.c gdbstub.c.bkp -353d352 -< case IDX_SEG_REGS + 8: -354a354 -> case IDX_SEG_REGS + 8: -362,363d361 -< #else -< return 4;
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