Hi Laszlo, We've found this issue. The patch for it has sent out at
https://lists.01.org/pipermail/edk2-devel/2018-January/020467.html It will be checked in soon. Regards, Jian > -----Original Message----- > From: Laszlo Ersek [mailto:ler...@redhat.com] > Sent: Monday, January 29, 2018 5:44 AM > To: Wang, Jian J <jian.j.w...@intel.com>; edk2-devel@lists.01.org > Cc: Ni, Ruiyu <ruiyu...@intel.com>; Yao, Jiewen <jiewen....@intel.com>; Dong, > Eric <eric.d...@intel.com> > Subject: Re: [edk2] [PATCH 1/6] UefiCpuPkg/MpInitLib: split wake up buffer > into > two parts > > On 01/27/18 17:17, Laszlo Ersek wrote: > > Hello Jian, > > > > On 01/15/18 09:54, Jian J Wang wrote: > >> If PcdDxeNxMemoryProtectionPolicy is set to enable protection for memory > >> of EfiBootServicesCode, EfiConventionalMemory, the BIOS will hang at a > page > >> fault exception during MP initialization. > >> > >> The root cause is that the AP wake up buffer, which is below 1MB and used > >> to hold both AP init code and data, is type of EfiConventionalMemory (not > >> really allocated because of potential conflict with legacy code), and is > >> marked as non-executable. During the transition from real address mode > >> to long mode, the AP init code has to enable paging which will then cause > >> itself a page fault exception because it's just running in non-executable > >> memory. > >> > >> The solution is splitting AP wake up buffer into two part: lower part is > >> still below 1MB and shared with legacy system, higher part is really > >> allocated memory of BootServicesCode type. The init code in the memory > >> below 1MB will not enable paging but just switch to protected mode and > >> jump to higher memory, in which the init code will enable paging and > >> switch to long mode. > >> > >> Cc: Jiewen Yao <jiewen....@intel.com> > >> Cc: Ruiyu Ni <ruiyu...@intel.com> > >> Cc: Eric Dong <eric.d...@intel.com> > >> Cc: Laszlo Ersek <ler...@redhat.com> > >> Contributed-under: TianoCore Contribution Agreement 1.1 > >> Signed-off-by: Jian J Wang <jian.j.w...@intel.com> > >> --- > >> UefiCpuPkg/Library/MpInitLib/DxeMpLib.c | 34 ++++++++++ > >> UefiCpuPkg/Library/MpInitLib/Ia32/MpEqu.inc | 5 ++ > >> UefiCpuPkg/Library/MpInitLib/Ia32/MpFuncs.nasm | 32 +++++----- > >> UefiCpuPkg/Library/MpInitLib/MpLib.c | 45 +++++++++++++ > >> UefiCpuPkg/Library/MpInitLib/MpLib.h | 22 +++++++ > >> UefiCpuPkg/Library/MpInitLib/PeiMpLib.c | 23 +++++++ > >> UefiCpuPkg/Library/MpInitLib/X64/MpEqu.inc | 5 +- > >> UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm | 87 ++++++++++++++++- > --------- > >> 8 files changed, 204 insertions(+), 49 deletions(-) > > > > This patch breaks OVMF on KVM. The symptom is that the guest crashes > > and reboots as follows (infinite reboot loop): > > > >> Loading PEIM at 0x0007FEB0000 EntryPoint=0x0007FEB5C96 CpuMpPei.efi > >> AP Loop Mode is 1 > >> WakeupBufferStart = 9F000, WakeupBufferSize = 1000 > >> -- crash & reboot here -- > >> SecCoreStartupWithStack(0xFFFCC000, 0x820000) > > The following build options were used for this build: > > $ build -a X64 -p OvmfPkg/OvmfPkgX64.dsc -D SECURE_BOOT_ENABLE \ > -t GCC48 -b NOOPT -D HTTP_BOOT_ENABLE > > The tree was built at 06c1f423e17f ("BeagleBoardPkg: reroute Firmware > Vendor Pcd to MdeModulePkg", 2018-01-26). (This commit is listed at the > top of the bisection log in my previous email.) > > Here's the KVM log up to the triple fault: > > > CPU-32283 [004] 13652.374591: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374594: kvm_exit: reason > > CR_ACCESS > rip 0x3a info 0 0 > > CPU-32283 [004] 13652.374595: kvm_cr: cr_write 0 > > = > 0x60000013 > > CPU-32283 [004] 13652.374596: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374597: kvm_exit: reason > > CR_ACCESS > rip 0x9f06a info 4 0 > > CPU-32283 [004] 13652.374598: kvm_cr: cr_write 4 > > = 0x20 > > CPU-32283 [004] 13652.374603: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374604: kvm_exit: reason > > CR_ACCESS > rip 0x9f075 info 103 0 > > CPU-32283 [004] 13652.374605: kvm_cr: cr_write 3 > > = 0x800000 > > CPU-32283 [004] 13652.374606: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374607: kvm_exit: reason > > MSR_READ > rip 0x9f07d info 0 0 > > CPU-32283 [004] 13652.374608: kvm_msr: msr_read > > c0000080 > = 0x0 > > CPU-32283 [004] 13652.374608: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374609: kvm_exit: reason > > MSR_WRITE > rip 0x9f083 info 0 0 > > CPU-32283 [004] 13652.374611: kvm_msr: msr_write > > c0000080 > = 0x100 > > CPU-32283 [004] 13652.374612: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374613: kvm_exit: reason > > CR_ACCESS > rip 0x9f08c info 0 0 > > CPU-32283 [004] 13652.374613: kvm_cr: cr_write 0 > > = > 0xe0000013 > > CPU-32283 [004] 13652.374620: kvm_entry: vcpu 2 > > CPU-32283 [004] 13652.374622: kvm_exit: reason > TRIPLE_FAULT rip 0x9f096 info 0 0 > > Offset 0x96 (relative to 0x9F000) is from > "UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm": > > > 5c66d125eaae5 (Jeff Fan 2016-07-29 21:13:34 +0800 103) > SkipEnableExecuteDisableBit: > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 104) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 105) ; Enable > > PAE > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 106) ; > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 107) mov > > eax, > cr4 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 108) bts > > eax, 5 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 109) mov > > cr4, > eax > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 110) > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 111) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 112) ; Load page > table > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 113) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 114) mov > > esi, > Cr3Location ; Save CR3 in ecx > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 115) mov > > ecx, > [ebx + esi] > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 116) mov > > cr3, > ecx ; Load CR3 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 117) > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 118) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 119) ; Enable > > long > mode > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 120) ; > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 121) mov > > ecx, > 0c0000080h ; EFER MSR number > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 122) > rdmsr ; Read EFER > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 123) bts > > eax, > 8 ; Set LME=1 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 124) > wrmsr ; Write EFER > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 125) > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 126) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 127) ; Enable > paging > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 128) ; > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 129) mov > > eax, > cr0 ; Read CR0 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 130) bts > > eax, > 31 ; Set PG=1 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 131) mov > > cr0, > eax ; Write CR0 > > d94e5f672994f (Jeff Fan 2016-07-20 22:44:39 +0800 132) > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 133) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 134) ; Far jump > > to > 64-bit code > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 135) ; > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 136) mov > > edi, > ModeHighMemoryLocation > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 137) add > > edi, > ebx > > f32bfe6d06142 (Jian J Wang 2017-12-29 09:12:54 +0800 138) jmp far > > [edi] > <- here > > Thanks > Laszlo _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
