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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Peter Zijlstra' <peterz@infradead.org>,
        "x86@kernel.org" <x86@kernel.org>
CC:     Kees Cook <keescook@chromium.org>,
        Sami Tolvanen <samitolvanen@google.com>,
        Joao Moreira <joao@overdrivepizza.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: RE: [PATCH] x86/ibt: Implement FineIBT
Thread-Topic: [PATCH] x86/ibt: Implement FineIBT
Thread-Index: AQHY4vaTWxnEUTsnZEq6+EVM+oAeM64UOHoQ
Date:   Tue, 18 Oct 2022 14:43:01 +0000
Message-ID: <9bb036e48580454b81e6de7224c5f006@AcuMS.aculab.com>
References: <Y06rtoE9BsERG9uv@hirez.programming.kicks-ass.net>
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From: Peter Zijlstra
> Sent: 18 October 2022 14:36
> 
> Implement an alternative CFI scheme that merges both the fine-grained
> nature of kCFI but also takes full advantage of the coarse grained
> hardware CFI as provided by IBT.

Does the hash value for kCFI only depend on the function type?
Or is there something like a attribute that can also be included?

Otherwise all void (*)(void *) functions have the same hash.

Any such additional check would also improve compile-time checks.

	David

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