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| author | Amit Daniel Kachhap <amit.kachhap@arm.com> | 2020-09-14 11:36:53 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2020-09-14 14:07:02 +0300 |
| commit | e16aeb072682d3dcdbdad452c974baa0d2b0c6db (patch) | |
| tree | 20484ed8c1c59204ef50fb524fa206e6198e63f9 /arch/arm64/include/asm/sysreg.h | |
| parent | 4ef333b2d10680b5d966a733ed7171f72164fcd5 (diff) | |
| download | linux-e16aeb072682d3dcdbdad452c974baa0d2b0c6db.tar.xz | |
arm64: ptrauth: Introduce Armv8.3 pointer authentication enhancements
Some Armv8.3 Pointer Authentication enhancements have been introduced
which are mandatory for Armv8.6 and optional for Armv8.3. These features
are,
* ARMv8.3-PAuth2 - An enhanced PAC generation logic is added which hardens
finding the correct PAC value of the authenticated pointer.
* ARMv8.3-FPAC - Fault is generated now when the ptrauth authentication
instruction fails in authenticating the PAC present in the address.
This is different from earlier case when such failures just adds an
error code in the top byte and waits for subsequent load/store to abort.
The ptrauth instructions which may cause this fault are autiasp, retaa
etc.
The above features are now represented by additional configurations
for the Address Authentication cpufeature and a new ESR exception class.
The userspace fault received in the kernel due to ARMv8.3-FPAC is treated
as Illegal instruction and hence signal SIGILL is injected with ILL_ILLOPN
as the signal code. Note that this is different from earlier ARMv8.3
ptrauth where signal SIGSEGV is issued due to Pointer authentication
failures. The in-kernel PAC fault causes kernel to crash.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20200914083656.21428-4-amit.kachhap@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/sysreg.h')
| -rw-r--r-- | arch/arm64/include/asm/sysreg.h | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 554a7e8ecb07..b738bc793369 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -636,14 +636,22 @@ #define ID_AA64ISAR1_APA_SHIFT 4 #define ID_AA64ISAR1_DPB_SHIFT 0 -#define ID_AA64ISAR1_APA_NI 0x0 -#define ID_AA64ISAR1_APA_ARCHITECTED 0x1 -#define ID_AA64ISAR1_API_NI 0x0 -#define ID_AA64ISAR1_API_IMP_DEF 0x1 -#define ID_AA64ISAR1_GPA_NI 0x0 -#define ID_AA64ISAR1_GPA_ARCHITECTED 0x1 -#define ID_AA64ISAR1_GPI_NI 0x0 -#define ID_AA64ISAR1_GPI_IMP_DEF 0x1 +#define ID_AA64ISAR1_APA_NI 0x0 +#define ID_AA64ISAR1_APA_ARCHITECTED 0x1 +#define ID_AA64ISAR1_APA_ARCH_EPAC 0x2 +#define ID_AA64ISAR1_APA_ARCH_EPAC2 0x3 +#define ID_AA64ISAR1_APA_ARCH_EPAC2_FPAC 0x4 +#define ID_AA64ISAR1_APA_ARCH_EPAC2_FPAC_CMB 0x5 +#define ID_AA64ISAR1_API_NI 0x0 +#define ID_AA64ISAR1_API_IMP_DEF 0x1 +#define ID_AA64ISAR1_API_IMP_DEF_EPAC 0x2 +#define ID_AA64ISAR1_API_IMP_DEF_EPAC2 0x3 +#define ID_AA64ISAR1_API_IMP_DEF_EPAC2_FPAC 0x4 +#define ID_AA64ISAR1_API_IMP_DEF_EPAC2_FPAC_CMB 0x5 +#define ID_AA64ISAR1_GPA_NI 0x0 +#define ID_AA64ISAR1_GPA_ARCHITECTED 0x1 +#define ID_AA64ISAR1_GPI_NI 0x0 +#define ID_AA64ISAR1_GPI_IMP_DEF 0x1 /* id_aa64pfr0 */ #define ID_AA64PFR0_CSV3_SHIFT 60 |