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From: Florian Weimer <fweimer@redhat.com>
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: "H.J. Lu" <hjl.tools@gmail.com>,  "H.J. Lu via Libc-alpha"
 <libc-alpha@sourceware.org>,  Joseph Myers <joseph@codesourcery.com>
Subject: Re: [RFC] <sys/tagged-address.h>: An API for tagged address
References: <20210211173711.71736-1-hjl.tools@gmail.com>
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 <20210218131751.GC12795@arm.com>
Date: Thu, 18 Feb 2021 14:21:42 +0100
In-Reply-To: <20210218131751.GC12795@arm.com> (Szabolcs Nagy's message of
 "Thu, 18 Feb 2021 13:17:53 +0000")
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* Szabolcs Nagy:

> we want the libc to decide early about the tagged syscall abi,
> later there is no reliable way to do it for the entire process.
> for this we may need to mark binaries that use tags (such
> marking also tells us that the binary is not MTE compatible)
> unfortunately HWASAN does not use any marking. (lack of marking
> is an issue in other sanitizers too). currently the opt-in is
> done based on a tunable that requests heap tagging.

Apparently x86 has a similar issue, see Kirill's comment that
H.J. relayed:

  <https://sourceware.org/pipermail/libc-alpha/2021-February/122775.html>

Thanks,
Florian