| Message ID | 20210423175134.14838-1-catalin.marinas@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: doc: Add brk/mmap/mremap() to the Tagged Address ABI Exceptions | expand |
On Fri, 23 Apr 2021 18:51:34 +0100, Catalin Marinas wrote: > Prior to commit dcde237319e6 ("mm: Avoid creating virtual address > aliases in brk()/mmap()/mremap()"), the kernel allowed tagged addresses > to be passed to the brk/mmap/mremap() syscalls. This relaxation was > tightened in 5.6 (backported to stable 5.4) but the > tagged-address-abi.rst document was only partially updated. Applied to arm64 (for-next/core), thanks! [1/1] arm64: doc: Add brk/mmap/mremap() to the Tagged Address ABI Exceptions https://git.kernel.org/arm64/c/75516c75a72b
diff --git a/Documentation/arm64/tagged-address-abi.rst b/Documentation/arm64/tagged-address-abi.rst index cbc4d4500241..459e6b66ff68 100644 --- a/Documentation/arm64/tagged-address-abi.rst +++ b/Documentation/arm64/tagged-address-abi.rst @@ -113,6 +113,12 @@ ABI relaxation: - ``shmat()`` and ``shmdt()``. +- ``brk()`` (since kernel v5.6). + +- ``mmap()`` (since kernel v5.6). + +- ``mremap()``, the ``new_address`` argument (since kernel v5.6). + Any attempt to use non-zero tagged pointers may result in an error code being returned, a (fatal) signal being raised, or other modes of failure.
Prior to commit dcde237319e6 ("mm: Avoid creating virtual address aliases in brk()/mmap()/mremap()"), the kernel allowed tagged addresses to be passed to the brk/mmap/mremap() syscalls. This relaxation was tightened in 5.6 (backported to stable 5.4) but the tagged-address-abi.rst document was only partially updated. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Fixes: dcde237319e6 ("mm: Avoid creating virtual address aliases in brk()/mmap()/mremap()") Reported-by: Peter Maydell <peter.maydell@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> --- Documentation/arm64/tagged-address-abi.rst | 6 ++++++ 1 file changed, 6 insertions(+)