Re: [PATCH v6 07/13] arm64: add basic pointer authentication support
From: Mark Rutland <mark.rutland@arm.com>
Date: 2019-01-04 18:02:26
Also in:
kvmarm, lkml
On Fri, Jan 04, 2019 at 10:33:40AM +0100, Pavel Machek wrote:
On Fri 2019-01-04 09:21:30, Marc Zyngier wrote:quoted
On 03/01/2019 20:29, Pavel Machek wrote:quoted
On Fri 2018-12-07 18:39:25, Kristina Martsenko wrote:quoted
From: Mark Rutland <mark.rutland@arm.com> This patch adds basic support for pointer authentication, allowing userspace to make use of APIAKey, APIBKey, APDAKey, APDBKey, and APGAKey. The kernel maintains key values for each process (shared by all threads within), which are initialised to random values at exec()time. ...quoted
+/* + * We give each process its own keys, which are shared by all threads. The keys + * are inherited upon fork(), and reinitialised upon exec*(). + */ +struct ptrauth_keys { + struct ptrauth_key apia; + struct ptrauth_key apib; + struct ptrauth_key apda; + struct ptrauth_key apdb; + struct ptrauth_key apga; +};intstruction_a, data_a, generic_a? Should be easier to understand than "apdb" ...... until you realize that these names do match the documentation, which makes it even easier to understand how the code uses the architecture.See how not even the commit log matches the documentation then?
The commit message exactly matches the documentation, as it refers to: APIAKey, APIBKey, APDAKey, APDBKey, and APGAKey ... which are the architected names for those registers, in all the documentation. Searching "apga" in the ARM ARM finds all of the relevant information on APGAKey_EL1. Searching "generic_a" finds precisely nothing, as it's a term which you invented, that no-one else has previously used. Likewise for the other key names.
Naming something "apdb" is just bad... Just because the documentation is evil does not mean it should be followed...
It is in no way evil to use the documented names for things. It is unhelpful to make up terminology that no-one else uses. Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel