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Diffstat (limited to 'results/classifier/105/other/1389')
| -rw-r--r-- | results/classifier/105/other/1389 | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/results/classifier/105/other/1389 b/results/classifier/105/other/1389 new file mode 100644 index 00000000..1bee9e04 --- /dev/null +++ b/results/classifier/105/other/1389 @@ -0,0 +1,74 @@ +other: 0.796 +instruction: 0.795 +vnc: 0.785 +boot: 0.749 +graphic: 0.732 +mistranslation: 0.701 +assembly: 0.679 +device: 0.675 +socket: 0.602 +network: 0.588 +semantic: 0.515 +KVM: 0.447 + +Qemu 7.2.0 My hobbby bootloader seemed to stop working +Description of problem: +I wrote a BIOS bootloader and OS, but updated to QEMU 7.2.0 and now I get an exception in my bootloader. +Specifically I am getting a page fault on the first line of map_pd: +``` +next_pdpt: + ; PDPT + mov [0xa000 + rdx * 8], rax ; PDPT[rdx] -> PD + and al, 0xfc ;; clear bits 1 and 2 + + mov rcx, 0 +map_pd: + mov [rax + rcx * 8], rdi ; PD[rcx] -> rax + add rdi, 0x200000 ; maps first 512 * 0x200000 or 1 GiB + sub rsi, 1 + cmp rsi, 0 + je done_map_rest + + add rcx, 1 + cmp rcx, 512 + jb map_pd + + add rdx, 1 ; do next GiB + add rax, 0x1000 ; next PD + or rax, (1 | 2) + + jmp next_pdpt +``` +I am getting the exception: +``` +check_exception old: 0xffffffff new 0xe + 0: v=0e e=0002 i=0 cpl=0 IP=0008:0000000000001311 pc=0000000000001311 SP=0010:0000000000007bf8 CR2=000000000020c000 +RAX=000000000020c000 RBX=00000000000b8040 RCX=0000000000000000 RDX=0000000000000201 +RSI=000000000003fe00 RDI=0000008040000083 RBP=0000000000000008 RSP=0000000000007bf8 +R8 =0000000000000000 R9 =0000000000000000 R10=0000000000000000 R11=0000000000000000 +R12=0000000000000000 R13=0000000000000000 R14=0000000000000000 R15=0000000000000000 +RIP=0000000000001311 RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0 +ES =0010 0000000000000000 00000000 00009300 DPL=0 DS [-WA] +CS =0008 0000000000000000 00000000 00209a00 DPL=0 CS64 [-R-] +SS =0010 0000000000000000 00000000 00009300 DPL=0 DS [-WA] +DS =0010 0000000000000000 00000000 00009300 DPL=0 DS [-WA] +FS =0010 0000000000000000 00000000 00009300 DPL=0 DS [-WA] +GS =0010 0000000000000000 00000000 00009300 DPL=0 DS [-WA] +LDT=0000 0000000000000000 0000ffff 00008200 DPL=0 LDT +TR =0000 0000000000000000 0000ffff 00008b00 DPL=0 TSS64-busy +GDT= 0000000000001888 00000018 +IDT= 0000000090909000 00000000 +CR0=80000011 CR2=000000000020c000 CR3=0000000000009000 CR4=00000020 +DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000 +DR6=00000000ffff0ff0 DR7=0000000000000400 +CCS=0000000000000200 CCD=0000000000000000 CCO=LOGICB +EFER=0000000000000500 +``` + +I am able to read the 0x20c000 address with gdb +Steps to reproduce: +1. clone and build https://github.com/darbysauter/myOS +2. run with `make run` on 7.0.0 +3. run with `make run` on 7.2.0 and there is an exception +Additional information: +I looked through the changelogs from 7.1 and 7.2 and nothing stood out to me. Not sure if some behaviour changed or some default changed. |