On 01/07/18 17:43, Michael Young wrote: > I am seeing crash on boot and DomU (pv) on Fedora with the 4.17 kernel > (eg. kernel-4.17.2-200.fc28.x86_64 and kernel-4.17.3-200.fc28.x86_64) > which > didn't occur with 4.16 kernel (eg. kernel-4.16.16-300.fc28.x86_64) > > The backtrace for a Dom0 boot of xen-4.10.1-5.fc28.x86_64 running > kernel-4.17.2-200.fc28.x86_64 is > > (XEN) d0v0 Unhandled general protection fault fault/trap [#13, ec=0000] > (XEN) domain_crash_sync called from entry.S: fault at ffff82d08035557c > x86_64/entry.S#create_bounce_frame+0x135/0x159 > (XEN) Domain 0 (vcpu#0) crashed on cpu#0: > (XEN) ----[ Xen-4.10.1 x86_64 debug=n Not tainted ]---- > (XEN) CPU: 0 > (XEN) RIP: e033:[<ffffffff81062330>] > (XEN) RFLAGS: 0000000000000246 EM: 1 CONTEXT: pv guest (d0v0) > (XEN) rax: 0000000000000246 rbx: 00000000ffffffff rcx: > 0000000000000000 > (XEN) rdx: 0000000000000000 rsi: 00000000ffffffff rdi: > 0000000000000000 > (XEN) rbp: 0000000000000000 rsp: ffffffff82203d90 r8: > ffffffff820bb698 > (XEN) r9: ffffffff82203e38 r10: 0000000000000000 r11: > 0000000000000000 > (XEN) r12: 0000000000000000 r13: ffffffff820bb698 r14: > ffffffff82203e38 > (XEN) r15: 0000000000000000 cr0: 0000000080050033 cr4: > 00000000000006e0 > (XEN) cr3: 000000001aacf000 cr2: 0000000000000000 > (XEN) fsb: 0000000000000000 gsb: ffffffff82731000 gss: > 0000000000000000 > (XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033 > (XEN) Guest stack trace from rsp=ffffffff82203d90: > (XEN) 0000000000000000 0000000000000000 0000000000000000 > ffffffff81062330 > (XEN) 000000010000e030 0000000000010046 ffffffff82203dd8 > 000000000000e02b > (XEN) 0000000000000246 ffffffff8110e019 0000000000000000 > 0000000000000246 > (XEN) 0000000000000000 0000000000000000 ffffffff820a6cd8 > ffffffff82203e88 > (XEN) ffffffff82739000 8000000000000061 0000000000000000 > 0000000000000000 > (XEN) ffffffff8110ecb6 0000000000000008 ffffffff82203e98 > ffffffff82203e58 > (XEN) 0000000000000000 0000000000000000 8000000000000161 > 0000000000000100 > (XEN) fffffffffffffeff 0000000000000000 0000000000000000 > ffffffff82203ef0 > (XEN) ffffffff810ac990 0000000000000000 0000000000000000 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 8000000000000161 > 0000000000000100 > (XEN) fffffffffffffeff 0000000000000000 0000000000000000 > 0000000002739000 > (XEN) 0000000000000080 ffffffff8275db62 000000000001a739 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 > ffffffff81037c80 > (XEN) 007fffff8275efe7 ffffffff82739000 ffffffff81037f18 > ffffffff8102aaf0 > (XEN) ffffffff8275dc8c 0000000000000000 0000000000000000 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0000000000000000 > 0000000000000000 > (XEN) 0000000000000000 0000000000000000 0f00000060c0c748 > ccccccccccccc305 > > where > addr2line -f -e vmlinux ffffffff81062330 > gives > native_irq_disable > /usr/src/debug/kernel-4.17.fc28/linux-4.17.2-200.fc28.x86_64/./arch/x86/include/asm/irqflags.h:44 > > > What is the problem or how might it be debugged?
The guest is executing a native `cli` instruction which is privileged and we don't allow (we could trap & emulate, but we can't provide proper STI-shadow behaviour, and such a guest might also expect popf to work, which is very much doesnt). In Linux, that codepath should be using a pvop, rather than a native op. It is either a subsystem which should be skipped when virtualised, or a poorly coded subsystem, or a buggy setup path. Can you see about trying to boot the old kernel as dom0, and the new kernel as a domU with pause on crash configured? /usr/libexec/xen/bin/xenctx should be able to pull a backtrace out of the crashed domain state if you pass the appropriate symbol table in. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
