2017-08-05 6:03 GMT+08:00 Anatol Pomozov <anatol.pomozov@xxxxxxxxx>: > Hello > > I am testing my own x86_64 kernel with QEMU/KVM and it report cryptic > error "KVM internal error. Suberror: 1". I believe this emulation > error happens in Linux kernel most likely in arch/x86/kvm/emulate.c > > I tested KVM with Linux 4.4.0, 4.12.3 and both versions return this > emulation error. It is strange as QEMU emulation and VMWare work fine > with the same kernel binary. > > > How to understand what is the KVM issue and why it fails? Is there a > way to obtain more information about the error? Coud you post your testcase? Regards, Wanpeng Li > > > Here is my code where the issue happens: > > 0000000000100c20 <console_write>: > 100c20: 48 85 f6 test %rsi,%rsi > 100c23: 0f 84 11 05 00 00 je 10113a <console_write+0x51a> > 100c29: 45 31 c0 xor %r8d,%r8d > 100c2c: b9 0e 8f 0b 00 mov $0xb8f0e,%ecx > 100c31: 66 66 66 66 66 66 2e data32 data32 data32 data32 > data32 nopw %cs:0x0(%rax,%rax,1) > 100c38: 0f 1f 84 00 00 00 00 > 100c3f: 00 > 100c40: 0f be 07 movsbl (%rdi),%eax > 100c43: 0f b7 d0 movzwl %ax,%edx > 100c46: 83 fa 0a cmp $0xa,%edx > 100c49: 0f 85 91 00 00 00 jne 100ce0 <console_write+0xc0> > 100c4f: 48 8b 05 aa 83 00 00 mov 0x83aa(%rip),%rax > # 109000 <row> > 100c56: 48 8d 50 01 lea 0x1(%rax),%rdx > 100c5a: 48 89 15 9f 83 00 00 mov %rdx,0x839f(%rip) > # 109000 <row> > 100c61: 48 83 fa 19 cmp $0x19,%rdx > 100c65: 0f 85 35 04 00 00 jne 1010a0 <console_write+0x480> > 100c6b: 31 d2 xor %edx,%edx > 100c6d: 0f 1f 00 nopl (%rax) > 100c70: 0f 10 84 51 92 f1 ff movups -0xe6e(%rcx,%rdx,2),%xmm0 > > ^^^^^^^^^^^^ KVM error happens here ^^^^^^^ See registers stack below > > 100c77: ff > 100c78: 0f 11 84 51 f2 f0 ff movups %xmm0,-0xf0e(%rcx,%rdx,2) > 100c7f: ff > 100c80: 48 83 c2 08 add $0x8,%rdx > 100c84: 48 81 fa 80 07 00 00 cmp $0x780,%rdx > 100c8b: 75 e3 jne 100c70 <console_write+0x50> > 100c8d: 48 89 05 6c 83 00 00 mov %rax,0x836c(%rip) > # 109000 <row> > 100c94: 48 c7 05 c1 3b 00 00 movq $0xb8f00,0x3bc1(%rip) > # 104860 <cursor> > 100c9b: 00 8f 0b 00 > 100c9f: 4c 8b 0d 62 83 00 00 mov 0x8362(%rip),%r9 > # 109008 <column> > 100ca6: 4d 85 c9 test %r9,%r9 > 100ca9: 0f 84 71 04 00 00 je 101120 <console_write+0x500> > 100caf: 49 8d 41 ff lea -0x1(%r9),%rax > 100cb3: 44 89 ca mov %r9d,%edx > 100cb6: 83 e2 07 and $0x7,%edx > 100cb9: 48 83 f8 07 cmp $0x7,%rax > 100cbd: 0f 83 f6 03 00 00 jae 1010b9 <console_write+0x499> > > > > > > Registers at KVM error as reported by QEMU > > RAX=0000000000000018 RBX=0000000000000001 RCX=00000000000b8f0e > RDX=0000000000000000 > RSI=0000000000000001 RDI=000000000010445a RBP=000000000010445b > RSP=000000000010af78 > R8 =0000000000000000 R9 =00000000000b8f56 R10=000000000010445c > R11=0000000000000004 > R12=000000000010445a R13=000000007fffffd3 R14=0000000000000001 > R15=000000000000002c > RIP=0000000000100c70 RFL=00010246 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0 > ES =0000 0000000000000000 ffffffff 00c00000 > CS =0008 0000000000000000 00000000 00209900 DPL=0 CS64 [--A] > SS =0000 0000000000000000 ffffffff 00c00000 > DS =0000 0000000000000000 ffffffff 00c00000 > FS =0000 0000000000000000 ffffffff 00c00000 > GS =0000 0000000000000000 ffffffff 00c00000 > LDT=0000 0000000000000000 0000ffff 00008200 DPL=0 LDT > TR =0000 0000000000000000 0000ffff 00008b00 DPL=0 TSS64-busy > GDT= 0000000000104518 0000000f > IDT= 0000000000105030 00000fff > CR0=80000033 CR2=0000000000000000 CR3=0000000000107000 CR4=00000620 > DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 > DR3=0000000000000000 > DR6=00000000ffff0ff0 DR7=0000000000000400 > EFER=0000000000000500
