diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/arm64/tagged-address-abi.rst | 26 | ||||
-rw-r--r-- | Documentation/trace/histogram.rst | 2 |
2 files changed, 19 insertions, 9 deletions
diff --git a/Documentation/arm64/tagged-address-abi.rst b/Documentation/arm64/tagged-address-abi.rst index 4a9d9c794ee5..7d255249094d 100644 --- a/Documentation/arm64/tagged-address-abi.rst +++ b/Documentation/arm64/tagged-address-abi.rst @@ -45,14 +45,24 @@ how the user addresses are used by the kernel: 1. User addresses not accessed by the kernel but used for address space management (e.g. ``mprotect()``, ``madvise()``). The use of valid - tagged pointers in this context is allowed with the exception of - ``brk()``, ``mmap()`` and the ``new_address`` argument to - ``mremap()`` as these have the potential to alias with existing - user addresses. - - NOTE: This behaviour changed in v5.6 and so some earlier kernels may - incorrectly accept valid tagged pointers for the ``brk()``, - ``mmap()`` and ``mremap()`` system calls. + tagged pointers in this context is allowed with these exceptions: + + - ``brk()``, ``mmap()`` and the ``new_address`` argument to + ``mremap()`` as these have the potential to alias with existing + user addresses. + + NOTE: This behaviour changed in v5.6 and so some earlier kernels may + incorrectly accept valid tagged pointers for the ``brk()``, + ``mmap()`` and ``mremap()`` system calls. + + - The ``range.start``, ``start`` and ``dst`` arguments to the + ``UFFDIO_*`` ``ioctl()``s used on a file descriptor obtained from + ``userfaultfd()``, as fault addresses subsequently obtained by reading + the file descriptor will be untagged, which may otherwise confuse + tag-unaware programs. + + NOTE: This behaviour changed in v5.14 and so some earlier kernels may + incorrectly accept valid tagged pointers for this system call. 2. User addresses accessed by the kernel (e.g. ``write()``). This ABI relaxation is disabled by default and the application thread needs to diff --git a/Documentation/trace/histogram.rst b/Documentation/trace/histogram.rst index 8408670d0328..3f3d1b960fe7 100644 --- a/Documentation/trace/histogram.rst +++ b/Documentation/trace/histogram.rst @@ -191,7 +191,7 @@ Documentation written by Tom Zanussi with the event, in nanoseconds. May be modified by .usecs to have timestamps interpreted as microseconds. - cpu int the cpu on which the event occurred. + common_cpu int the cpu on which the event occurred. ====================== ==== ======================================= Extended error information |