On Fri, 03 Jan, at 04:39:38PM, Madper Xie wrote: > Howdy Folks, > Happy new yeah, happy new bug! > With a uefi system, I meet following panic when reboot after I adding > `reboot=efi,warm` > [call trace]: > <0>[ 698.736637] reboot: Restarting system > <5>[ 698.737407] reboot: machine restart > <1>[ 698.738399] BUG: unable to handle kernel paging request at 00000000ded53e60 > <1>[ 698.738924] IP: [<ffff8800dedb946d>] 0xffff8800dedb946d > <4>[ 698.739408] PGD 0 > <4>[ 698.739868] Oops: 0000 [#1] SMP [...] > According to Call Trace, the panic happen when call ResetSystem() which > is a uefi run time service. It's seems a asm code in efi_stub_64.S > I disassembly it with crash got following outputs: > crash> dis efi_call4 > 0xffffffff810518f0 <efi_call4>: mov %rsp,%rax > [ ... ] > 0xffffffff81051918 <efi_call4+40>: movaps %xmm3,0x30(%rsp) > 0xffffffff8105191d <efi_call4+45>: movaps %xmm4,0x20(%rsp) > 0xffffffff81051922 <efi_call4+50>: movaps %xmm5,0x10(%rsp) > 0xffffffff81051927 <efi_call4+55>: sub $0x20,%rsp > [ ... ] > > So it seems the panic happen when SAVE_XMM? Does SAVE_XMM will trigger > paging? (`unable to handle kernel paging request at 00000000ded53e60`) No, the crash is happening within the ResetSystem() runtime service. Checkout the RIP, it's in the direct mapping region (0xffff8800.....). > in case it's a hardware special issue: My testbed is a DELL xps x8500 > And I'll try to test it on another uefi system. It looks like your firmware is trying to access physical addresses. Can you build a kernel from the 'next' branch at, git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git That branch includes Borislav's 1:1 mapping work and may fix your issue. -- Matt Fleming, Intel Open Source Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
