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authorYao, Jiewen <jiewen.yao@intel.com>2015-11-30 19:57:45 +0000
committerlersek <lersek@Edk2>2015-11-30 19:57:45 +0000
commit53ba3fb8aaf91df4a65244480deb6fa60968c146 (patch)
tree88fcdb7992f9d50dd1d46189e6c93491549e4a5d /UefiCpuPkg
parent881520ea6778953c57d975ca2a9cf3f2114f99c4 (diff)
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UefiCpuPkg/PiSmmCpu: Always set WP in CR0
So that we can use write-protection for code later. It is REPOST. It includes suggestion from Michael Kinney <michael.d.kinney@intel.com>: - "For IA32 assembly, can we combine into a single OR instruction that sets both page enable and WP?" - "For X64, does it make sense to use single OR instruction instead of 2 BTS instructions as well?" Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: "Yao, Jiewen" <jiewen.yao@intel.com> Suggested-by: Michael Kinney <michael.d.kinney@intel.com> Reviewed-by: Michael Kinney <michael.d.kinney@intel.com> Tested-by: Laszlo Ersek <lersek@redhat.com> Cc: "Fan, Jeff" <jeff.fan@intel.com> Cc: "Kinney, Michael D" <michael.d.kinney@intel.com> Cc: "Laszlo Ersek" <lersek@redhat.com> Cc: "Paolo Bonzini" <pbonzini@redhat.com> git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19068 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'UefiCpuPkg')
-rw-r--r--UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S2
-rw-r--r--UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm2
-rw-r--r--UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.S2
-rw-r--r--UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.asm2
4 files changed, 4 insertions, 4 deletions
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S
index fbaa0725f0..ec5b9a0b04 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S
@@ -123,7 +123,7 @@ L11:
L12: # as cr4.PGE is not set here, refresh cr3
movl %eax, %cr4 # in PreModifyMtrrs() to flush TLB.
movl %cr0, %ebx
- orl $0x080000000, %ebx # enable paging
+ orl $0x080010000, %ebx # enable paging + WP
movl %ebx, %cr0
leal DSC_OFFSET(%edi),%ebx
movw DSC_DS(%ebx),%ax
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm
index 8a12927300..ac1a9b48dd 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm
@@ -129,7 +129,7 @@ gSmiCr3 DD ?
@@: ; as cr4.PGE is not set here, refresh cr3
mov cr4, eax ; in PreModifyMtrrs() to flush TLB.
mov ebx, cr0
- or ebx, 080000000h ; enable paging
+ or ebx, 080010000h ; enable paging + WP
mov cr0, ebx
lea ebx, [edi + DSC_OFFSET]
mov ax, [ebx + DSC_DS]
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.S b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.S
index b488b74b70..7e9ac58cb2 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.S
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.S
@@ -144,7 +144,7 @@ Base:
orb $1,%ah
wrmsr
movq %cr0, %rbx
- btsl $31, %ebx
+ orl $0x080010000, %ebx # enable paging + WP
movq %rbx, %cr0
retf
LongMode: # long mode (64-bit code) starts here
diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.asm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.asm
index 4f5c03c5cf..094cf2c3da 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.asm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.asm
@@ -140,7 +140,7 @@ Base:
or ah, 1
wrmsr
mov rbx, cr0
- bts ebx, 31
+ or ebx, 080010000h ; enable paging + WP
mov cr0, rbx
retf
@LongMode: ; long mode (64-bit code) starts here