On 07/06/2019 13:07, Andrew Cooper wrote: > Currently, booting staging fails with: > > (XEN) Using APIC driver default > (XEN) ----[ Xen-4.13-unstable x86_64 debug=y Not tainted ]---- > (XEN) CPU: 0 > (XEN) RIP: e008:[<ffff82d08038f66e>] __x86_indirect_thunk_rax+0xe/0x10 > (XEN) RFLAGS: 0000000000010016 CONTEXT: hypervisor > (XEN) rax: c2c2c2c2c2c2c2c2 rbx: ffff83003f4cc000 rcx: 0000000000000000 > <snip> > (XEN) Xen code around <ffff82d08038f66e> > (__x86_indirect_thunk_rax+0xe/0x10): > (XEN) ae e8 eb fb 48 89 04 24 <c3> 90 e8 05 00 00 00 0f ae e8 eb fb 48 89 > 0c 24 > (XEN) Xen stack trace from rsp=ffff82d080827d28: > (XEN) c2c2c2c2c2c2c2c2 ffff82d080207588 ffff82d080827d68 0000000000000000 > <snip> > (XEN) Xen call trace: > (XEN) [<ffff82d08038f66e>] __x86_indirect_thunk_rax+0xe/0x10 > (XEN) [<ffff82d0806078a9>] setup_system_domains+0x18/0xab > (XEN) [<ffff82d08062d9c8>] __start_xen+0x1ea9/0x2935 > (XEN) [<ffff82d0802000f3>] __high_start+0x53/0x55 > (XEN) > (XEN) **************************************** > (XEN) Panic on CPU 0: > (XEN) GENERAL PROTECTION FAULT > (XEN) [error_code=0000] > (XEN) **************************************** > > UBSAN (which I happened to have active in my build at the time) identifies the > problem explicitly: > > (XEN) Using APIC driver default > (XEN) > ================================================================================ > (XEN) UBSAN: Undefined behaviour in > /local/xen.git/xen/include/xsm/xsm.h:309:19 > (XEN) member access within null pointer of type 'struct xsm_operations' > (XEN) ----[ Xen-4.13-unstable x86_64 debug=y Not tainted ]---- > > "adjust system domain creation (and call it earlier on x86)" didn't account > for the fact that domain_create() depends on XSM already being set up. There > is nothing very interesting which xsm_multiboot_init() more than allocating > memory, which means it is safe to move earlier during boot.
Oh - perhaps it is worth pointing out that we end up following the NULL function pointer xsm_ops->alloc_security_domain() and execute part of the 16bit IVT until we end up with the retpoline explosion. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
