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| author |   Vincenzo Frascino <vincenzo.frascino@arm.com> | 2019-08-23 17:37:17 +0100 |
|---|---|---|
| committer |   Will Deacon <will@kernel.org> | 2019-08-27 18:16:20 +0100 |
| commit | 92af2b696119e491a95d77acdd8832b582d300d4 (patch) | |
| tree | fccf2394ba5784c978d80758bef60bab04f8ca5f /arch/arm64/include/asm/thread_info.h | |
| parent | arm64: Add tagged-address-abi.rst to index.rst (diff) | |
| download | linux-dev-92af2b696119e491a95d77acdd8832b582d300d4.tar.xz linux-dev-92af2b696119e491a95d77acdd8832b582d300d4.zip | |
arm64: Relax Documentation/arm64/tagged-pointers.rst
On AArch64 the TCR_EL1.TBI0 bit is set by default, allowing userspace
(EL0) to perform memory accesses through 64-bit pointers with a non-zero
top byte. However, such pointers were not allowed at the user-kernel
syscall ABI boundary.
With the Tagged Address ABI patchset, it is now possible to pass tagged
pointers to the syscalls. Relax the requirements described in
tagged-pointers.rst to be compliant with the behaviours guaranteed by
the AArch64 Tagged Address ABI.
Cc: Will Deacon <will.deacon@arm.com>
Cc: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Co-developed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/thread_info.h')
0 files changed, 0 insertions, 0 deletions