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From: "Wang, Jian J" <jian.j.wang@intel.com>
To: Laszlo Ersek <lersek@redhat.com>,
	"edk2-devel@lists.01.org" <edk2-devel@lists.01.org>
Cc: "Ni, Ruiyu" <ruiyu.ni@intel.com>,
	"Yao, Jiewen" <jiewen.yao@intel.com>,
	"Dong, Eric" <eric.dong@intel.com>
Subject: Re: [PATCH 1/6] UefiCpuPkg/MpInitLib: split wake up buffer into two parts
Date: Mon, 29 Jan 2018 01:06:39 +0000	[thread overview]
Message-ID: <D827630B58408649ACB04F44C510003624CDF8DD@SHSMSX103.ccr.corp.intel.com> (raw)
In-Reply-To: <6264fc27-bf8d-5ee5-f631-31c28c32abeb@redhat.com>

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:lersek@redhat.com]
> Sent: Monday, January 29, 2018 5:44 AM
> To: Wang, Jian J <jian.j.wang@intel.com>; edk2-devel@lists.01.org
> Cc: Ni, Ruiyu <ruiyu.ni@intel.com>; Yao, Jiewen <jiewen.yao@intel.com>; Dong,
> Eric <eric.dong@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.yao@intel.com>
> >> Cc: Ruiyu Ni <ruiyu.ni@intel.com>
> >> Cc: Eric Dong <eric.dong@intel.com>
> >> Cc: Laszlo Ersek <lersek@redhat.com>
> >> Contributed-under: TianoCore Contribution Agreement 1.1
> >> Signed-off-by: Jian J Wang <jian.j.wang@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

  reply	other threads:[~2018-01-29  1:01 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-15  8:54 [PATCH 0/6] Fix issues caused by NX memory protection Jian J Wang
2018-01-15  8:54 ` [PATCH 1/6] UefiCpuPkg/MpInitLib: split wake up buffer into two parts Jian J Wang
2018-01-18  6:53   ` Dong, Eric
2018-01-27 16:17   ` Laszlo Ersek
2018-01-28 21:43     ` Laszlo Ersek
2018-01-29  1:06       ` Wang, Jian J [this message]
2018-01-29 15:50         ` Laszlo Ersek
2018-01-15  8:54 ` [PATCH 2/6] UefiCpuPkg/CpuExceptionHandlerLib: alloc code memory for exception handlers Jian J Wang
2018-01-16 14:02   ` Dong, Eric
2018-01-15  8:54 ` [PATCH 3/6] UefiCpuPkg/CpuDxe: clear NX attr for page directory Jian J Wang
2018-01-16 14:02   ` Dong, Eric
2018-01-15  8:54 ` [PATCH 4/6] UefiCpuPkg/PiSmmCpuDxeSmm: Enable NXE if it's supported Jian J Wang
2018-01-16 14:02   ` Dong, Eric
2018-01-28 22:46   ` Laszlo Ersek
2018-01-29  9:02     ` Wang, Jian J
2018-01-29 19:48       ` Laszlo Ersek
2018-01-30 13:09         ` Laszlo Ersek
2018-02-01  1:08         ` Wang, Jian J
2018-01-15  8:54 ` [PATCH 5/6] MdeModulePkg/PiSmmCore: remove NX attr for SMM RAM Jian J Wang
2018-01-15 10:18   ` Zeng, Star
2018-01-15  8:54 ` [PATCH 6/6] MdeModulePkg/BootScriptExecutorDxe: remove NX attr for FfsBuffer Jian J Wang
2018-01-15 10:18   ` Zeng, Star

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