| Message ID | 1460648907-18866-1-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | Accepted |
| Commit | 61b02ba1f2a3f80fa06f5006f0aea1572093a067 |
| Headers | show |
On Thu, Apr 14, 2016 at 05:48:27PM +0200, Ard Biesheuvel wrote: > On ARM, manipulating live page tables is cumbersome since the architecture > mandates the use of break-before-make, i.e., replacing a block entry with > a table entry requires an intermediate step via an invalid entry, or TLB > conflicts may occur. > > Since it is not generally feasible to decide in the page table manipulation > routines whether such an invalid entry will result in those routines > themselves to become unavailable, use a function that is callable with > the MMU off (i.e., a leaf function that does not access the stack) to > perform the change of a block entry into a table entry. > > Note that the opposite should never occur, i.e., table entries are never > coalesced into block entries. > > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Mark. > --- > ArmPkg/Include/Library/ArmLib.h | 6 ++ > ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf | 5 +- > ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c | 36 ++++++++++++ > ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c | 17 +++++- > ArmPkg/Library/ArmLib/AArch64/AArch64Support.S | 62 ++++++++++++++++++++ > 5 files changed, 124 insertions(+), 2 deletions(-) > > diff --git a/ArmPkg/Include/Library/ArmLib.h b/ArmPkg/Include/Library/ArmLib.h > index 15f610d82e1d..1689f0072db6 100644 > --- a/ArmPkg/Include/Library/ArmLib.h > +++ b/ArmPkg/Include/Library/ArmLib.h > @@ -613,4 +613,10 @@ ArmClearMemoryRegionReadOnly ( > IN UINT64 Length > ); > > +VOID > +ArmReplaceLiveTranslationEntry ( > + IN UINT64 *Entry, > + IN UINT64 Value > + ); > + > #endif // __ARM_LIB__ > diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf > index dd585dea91fb..58684e8492f2 100644 > --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf > +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf > @@ -17,9 +17,10 @@ [Defines] > INF_VERSION = 0x00010005 > BASE_NAME = AArch64Lib > FILE_GUID = ef20ddf5-b334-47b3-94cf-52ff44c29138 > - MODULE_TYPE = DXE_DRIVER > + MODULE_TYPE = BASE > VERSION_STRING = 1.0 > LIBRARY_CLASS = ArmLib > + CONSTRUCTOR = AArch64LibConstructor > > [Sources.AARCH64] > AArch64Lib.c > @@ -31,6 +32,7 @@ [Sources.AARCH64] > > ../Common/AArch64/ArmLibSupport.S > ../Common/ArmLib.c > + AArch64LibConstructor.c > > [Packages] > ArmPkg/ArmPkg.dec > @@ -38,6 +40,7 @@ [Packages] > > [LibraryClasses] > MemoryAllocationLib > + CacheMaintenanceLib > > [Protocols] > gEfiCpuArchProtocolGuid > diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c b/ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c > new file mode 100644 > index 000000000000..d2d0d3c15ee3 > --- /dev/null > +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c > @@ -0,0 +1,36 @@ > +#/* @file > +# > +# Copyright (c) 2016, Linaro Limited. All rights reserved. > +# > +# This program and the accompanying materials > +# are licensed and made available under the terms and conditions of the BSD License > +# which accompanies this distribution. The full text of the license may be found at > +# http://opensource.org/licenses/bsd-license.php > +# > +# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, > +# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. > +# > +#*/ > + > +#include <Base.h> > + > +#include <Library/ArmLib.h> > +#include <Library/CacheMaintenanceLib.h> > + > +RETURN_STATUS > +EFIAPI > +AArch64LibConstructor ( > + VOID > + ) > +{ > + extern UINT32 ArmReplaceLiveTranslationEntrySize; > + > + // > + // The ArmReplaceLiveTranslationEntry () helper function may be invoked > + // with the MMU off so we have to ensure that it gets cleaned to the PoC > + // > + WriteBackDataCacheRange (ArmReplaceLiveTranslationEntry, > + ArmReplaceLiveTranslationEntrySize); > + > + return RETURN_SUCCESS; > +} > diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c b/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c > index b7d23c6f3286..2cc6fc45aecf 100644 > --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c > +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c > @@ -169,6 +169,20 @@ GetRootTranslationTableInfo ( > > STATIC > VOID > +ReplaceLiveEntry ( > + IN UINT64 *Entry, > + IN UINT64 Value > + ) > +{ > + if (!ArmMmuEnabled ()) { > + *Entry = Value; > + } else { > + ArmReplaceLiveTranslationEntry (Entry, Value); > + } > +} > + > +STATIC > +VOID > LookupAddresstoRootTable ( > IN UINT64 MaxAddress, > OUT UINTN *T0SZ, > @@ -330,7 +344,8 @@ GetBlockEntryListFromAddress ( > } > > // Fill the BlockEntry with the new TranslationTable > - *BlockEntry = ((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE) | TableAttributes | TT_TYPE_TABLE_ENTRY; > + ReplaceLiveEntry (BlockEntry, > + ((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE) | TableAttributes | TT_TYPE_TABLE_ENTRY); > } > } else { > if (IndexLevel != PageLevel) { > diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S > index 1a3023b79487..43f7a795acec 100644 > --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S > +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S > @@ -56,6 +56,8 @@ GCC_ASM_EXPORT (ArmReadIdPfr1) > GCC_ASM_EXPORT (ArmWriteHcr) > GCC_ASM_EXPORT (ArmReadHcr) > GCC_ASM_EXPORT (ArmReadCurrentEL) > +GCC_ASM_EXPORT (ArmReplaceLiveTranslationEntry) > +GCC_ASM_EXPORT (ArmReplaceLiveTranslationEntrySize) > > .set CTRL_M_BIT, (1 << 0) > .set CTRL_A_BIT, (1 << 1) > @@ -481,4 +483,64 @@ ASM_PFX(ArmReadCurrentEL): > mrs x0, CurrentEL > ret > > + > + .macro __replace_entry, el > + > + // disable the MMU > + mrs x8, sctlr_el\el > + bic x9, x8, #CTRL_M_BIT > + msr sctlr_el\el, x9 > + isb > + > + // write updated entry > + str x1, [x0] > + > + // invalidate again to get rid of stale clean cachelines that may > + // have been filled speculatively since the last invalidate > + dmb sy > + dc ivac, x0 > + > + // flush the TLBs > + .if \el == 1 > + tlbi vmalle1 > + .else > + tlbi alle\el > + .endif > + dsb sy > + > + // re-enable the MMU > + msr sctlr_el\el, x8 > + isb > + .endm > + > +//VOID > +//ArmReplaceLiveTranslationEntry ( > +// IN UINT64 *Entry, > +// IN UINT64 Value > +// ) > +ASM_PFX(ArmReplaceLiveTranslationEntry): > + > + // disable interrupts > + mrs x2, daif > + msr daifset, #0xf > + isb > + > + // clean and invalidate first so that we don't clobber > + // adjacent entries that are dirty in the caches > + dc civac, x0 > + dsb ish > + > + EL1_OR_EL2_OR_EL3(x3) > +1:__replace_entry 1 > + b 4f > +2:__replace_entry 2 > + b 4f > +3:__replace_entry 3 > + > +4:msr daif, x2 > + ret > + > +ASM_PFX(ArmReplaceLiveTranslationEntrySize): > + .long . - ArmReplaceLiveTranslationEntry > + > ASM_FUNCTION_REMOVE_IF_UNREFERENCED > -- > 2.5.0 > _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
diff --git a/ArmPkg/Include/Library/ArmLib.h b/ArmPkg/Include/Library/ArmLib.h index 15f610d82e1d..1689f0072db6 100644 --- a/ArmPkg/Include/Library/ArmLib.h +++ b/ArmPkg/Include/Library/ArmLib.h @@ -613,4 +613,10 @@ ArmClearMemoryRegionReadOnly ( IN UINT64 Length ); +VOID +ArmReplaceLiveTranslationEntry ( + IN UINT64 *Entry, + IN UINT64 Value + ); + #endif // __ARM_LIB__ diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf index dd585dea91fb..58684e8492f2 100644 --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf @@ -17,9 +17,10 @@ [Defines] INF_VERSION = 0x00010005 BASE_NAME = AArch64Lib FILE_GUID = ef20ddf5-b334-47b3-94cf-52ff44c29138 - MODULE_TYPE = DXE_DRIVER + MODULE_TYPE = BASE VERSION_STRING = 1.0 LIBRARY_CLASS = ArmLib + CONSTRUCTOR = AArch64LibConstructor [Sources.AARCH64] AArch64Lib.c @@ -31,6 +32,7 @@ [Sources.AARCH64] ../Common/AArch64/ArmLibSupport.S ../Common/ArmLib.c + AArch64LibConstructor.c [Packages] ArmPkg/ArmPkg.dec @@ -38,6 +40,7 @@ [Packages] [LibraryClasses] MemoryAllocationLib + CacheMaintenanceLib [Protocols] gEfiCpuArchProtocolGuid diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c b/ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c new file mode 100644 index 000000000000..d2d0d3c15ee3 --- /dev/null +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c @@ -0,0 +1,36 @@ +#/* @file +# +# Copyright (c) 2016, Linaro Limited. All rights reserved. +# +# This program and the accompanying materials +# are licensed and made available under the terms and conditions of the BSD License +# which accompanies this distribution. The full text of the license may be found at +# http://opensource.org/licenses/bsd-license.php +# +# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +# +#*/ + +#include <Base.h> + +#include <Library/ArmLib.h> +#include <Library/CacheMaintenanceLib.h> + +RETURN_STATUS +EFIAPI +AArch64LibConstructor ( + VOID + ) +{ + extern UINT32 ArmReplaceLiveTranslationEntrySize; + + // + // The ArmReplaceLiveTranslationEntry () helper function may be invoked + // with the MMU off so we have to ensure that it gets cleaned to the PoC + // + WriteBackDataCacheRange (ArmReplaceLiveTranslationEntry, + ArmReplaceLiveTranslationEntrySize); + + return RETURN_SUCCESS; +} diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c b/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c index b7d23c6f3286..2cc6fc45aecf 100644 --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c @@ -169,6 +169,20 @@ GetRootTranslationTableInfo ( STATIC VOID +ReplaceLiveEntry ( + IN UINT64 *Entry, + IN UINT64 Value + ) +{ + if (!ArmMmuEnabled ()) { + *Entry = Value; + } else { + ArmReplaceLiveTranslationEntry (Entry, Value); + } +} + +STATIC +VOID LookupAddresstoRootTable ( IN UINT64 MaxAddress, OUT UINTN *T0SZ, @@ -330,7 +344,8 @@ GetBlockEntryListFromAddress ( } // Fill the BlockEntry with the new TranslationTable - *BlockEntry = ((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE) | TableAttributes | TT_TYPE_TABLE_ENTRY; + ReplaceLiveEntry (BlockEntry, + ((UINTN)TranslationTable & TT_ADDRESS_MASK_DESCRIPTION_TABLE) | TableAttributes | TT_TYPE_TABLE_ENTRY); } } else { if (IndexLevel != PageLevel) { diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S index 1a3023b79487..43f7a795acec 100644 --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S @@ -56,6 +56,8 @@ GCC_ASM_EXPORT (ArmReadIdPfr1) GCC_ASM_EXPORT (ArmWriteHcr) GCC_ASM_EXPORT (ArmReadHcr) GCC_ASM_EXPORT (ArmReadCurrentEL) +GCC_ASM_EXPORT (ArmReplaceLiveTranslationEntry) +GCC_ASM_EXPORT (ArmReplaceLiveTranslationEntrySize) .set CTRL_M_BIT, (1 << 0) .set CTRL_A_BIT, (1 << 1) @@ -481,4 +483,64 @@ ASM_PFX(ArmReadCurrentEL): mrs x0, CurrentEL ret + + .macro __replace_entry, el + + // disable the MMU + mrs x8, sctlr_el\el + bic x9, x8, #CTRL_M_BIT + msr sctlr_el\el, x9 + isb + + // write updated entry + str x1, [x0] + + // invalidate again to get rid of stale clean cachelines that may + // have been filled speculatively since the last invalidate + dmb sy + dc ivac, x0 + + // flush the TLBs + .if \el == 1 + tlbi vmalle1 + .else + tlbi alle\el + .endif + dsb sy + + // re-enable the MMU + msr sctlr_el\el, x8 + isb + .endm + +//VOID +//ArmReplaceLiveTranslationEntry ( +// IN UINT64 *Entry, +// IN UINT64 Value +// ) +ASM_PFX(ArmReplaceLiveTranslationEntry): + + // disable interrupts + mrs x2, daif + msr daifset, #0xf + isb + + // clean and invalidate first so that we don't clobber + // adjacent entries that are dirty in the caches + dc civac, x0 + dsb ish + + EL1_OR_EL2_OR_EL3(x3) +1:__replace_entry 1 + b 4f +2:__replace_entry 2 + b 4f +3:__replace_entry 3 + +4:msr daif, x2 + ret + +ASM_PFX(ArmReplaceLiveTranslationEntrySize): + .long . - ArmReplaceLiveTranslationEntry + ASM_FUNCTION_REMOVE_IF_UNREFERENCED
On ARM, manipulating live page tables is cumbersome since the architecture mandates the use of break-before-make, i.e., replacing a block entry with a table entry requires an intermediate step via an invalid entry, or TLB conflicts may occur. Since it is not generally feasible to decide in the page table manipulation routines whether such an invalid entry will result in those routines themselves to become unavailable, use a function that is callable with the MMU off (i.e., a leaf function that does not access the stack) to perform the change of a block entry into a table entry. Note that the opposite should never occur, i.e., table entries are never coalesced into block entries. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- ArmPkg/Include/Library/ArmLib.h | 6 ++ ArmPkg/Library/ArmLib/AArch64/AArch64Lib.inf | 5 +- ArmPkg/Library/ArmLib/AArch64/AArch64LibConstructor.c | 36 ++++++++++++ ArmPkg/Library/ArmLib/AArch64/AArch64Mmu.c | 17 +++++- ArmPkg/Library/ArmLib/AArch64/AArch64Support.S | 62 ++++++++++++++++++++ 5 files changed, 124 insertions(+), 2 deletions(-) -- 2.5.0 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel