aarch64: update NEWS about branch protection

After some discussions it seems the original news was not clear
and that it is valid to manually pass the branch protection flags
iff GCC target libs are built with them too. The main difference
between manually passing the flags and using the configure
option is that the latter also makes branch protection the
default in GCC which may not be desirable in some cases.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This commit is contained in:
Szabolcs Nagy 2020-07-29 08:27:27 +01:00
parent 17a0126abf
commit 42c9e9af22

4
NEWS
View File

@ -70,7 +70,9 @@ Major new features:
* AArch64 now supports standard branch protection security hardening * AArch64 now supports standard branch protection security hardening
in glibc when it is built with a GCC that is configured with in glibc when it is built with a GCC that is configured with
--enable-standard-branch-protection. This includes branch target --enable-standard-branch-protection (or if -mbranch-protection=standard
flag is passed when building both GCC target libraries and glibc,
in either case a custom GCC is needed). This includes branch target
identification (BTI) and pointer authentication for return addresses identification (BTI) and pointer authentication for return addresses
(PAC-RET). They require armv8.5-a and armv8.3-a architecture (PAC-RET). They require armv8.5-a and armv8.3-a architecture
extensions respectively for the protection to be effective, extensions respectively for the protection to be effective,