From 7e17dad9564c5375c45337889e6236708862e99a Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Wed, 19 Oct 2022 16:08:54 +0100 Subject: morello: Provide documentation about the morello port. --- manual/README.morello | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 manual/README.morello diff --git a/manual/README.morello b/manual/README.morello new file mode 100644 index 0000000000..8a2be21bd4 --- /dev/null +++ b/manual/README.morello @@ -0,0 +1,35 @@ +Morello glibc port +================== + +Morello is a prototype security architecture, led by Arm, based on CHERI. +https://www.morello-project.org/ +https://www.cl.cam.ac.uk/research/security/ctsrd/cheri/ + +Toolchain components of the morello port are maintained in upstream branches. +The morello port is implemented as an ABI variant of the aarch64 port that is +also called the purecap ABI. Morello specific ABI documents are at: +https://github.com/ARM-software/abi-aa +https://git.morello-project.org/morello/kernel/linux/-/wikis/home + +Areas with significant morello or CHERI specific changes outside the usual +target specific changes: + +- Early start code including ELF entry and auxv, +- Dynamic linker and relocation processing, +- malloc with narrow capability support, +- printf %#p to pretty print capabilities. + +Limitations of the morello port: + +- Building requires --disable-werror. +- Profiling and --enable-profile are not supported (gperf, sprof, LD_PROFILE). +- LD_AUDIT is not supported (symbind, PLT hooks, would require API redesign). +- VDSO is not supported (depends on Linux work). +- static-pie is not supported (requires start code redesign). +- POSIX message queue async notify does not work (pointers passed via an fd). +- Process shared robust mutexes don't work (pointers in shared memory). +- Purecap pldd only supports purecap ABI processes (not lp64). +- malloc has significant overhead (locks and hash table lookup). +- string functions are not optimized. +- Exectable stacks are not supported. +- Internal pointer protection and pointer mangling are disabled. -- cgit 1.4.1