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From:   Michael Ellerman <mpe@ellerman.id.au>
To:     Peter Zijlstra <peterz@infradead.org>,
        Joel Fernandes <joel@joelfernandes.org>
Cc:     Zhouyi Zhou <zhouzhouyi@gmail.com>,
        Christophe Leroy <christophe.leroy@c-s.fr>,
        Boqun Feng <boqun.feng@gmail.com>,
        Segher Boessenkool <segher@kernel.crashing.org>,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        rcu <rcu@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>, lance@osuosl.org,
        "Paul E. McKenney" <paulmck@kernel.org>
Subject: Re: BUG : PowerPC RCU: torture test failed with __stack_chk_fail
In-Reply-To: <20230426142054.GA1381951@hirez.programming.kicks-ass.net>
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Date:   Thu, 27 Apr 2023 00:45:44 +1000
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Peter Zijlstra <peterz@infradead.org> writes:
> On Wed, Apr 26, 2023 at 09:44:22AM -0400, Joel Fernandes wrote:
>
>> How could you control which code paths don't have the stack protector?
>> Just curious.
>
> https://lkml.kernel.org/r/20230412-no_stackp-v2-0-116f9fe4bbe7@google.com

We also have some entire files disabled, eg:

$ git grep no-stack-protector arch/powerpc/
arch/powerpc/kernel/Makefile:CFLAGS_prom_init.o += -fno-stack-protector
arch/powerpc/kernel/Makefile:CFLAGS_syscall.o += -fno-stack-protector
arch/powerpc/kernel/Makefile:CFLAGS_setup_64.o                += -fno-stack-protector
arch/powerpc/kernel/Makefile:CFLAGS_paca.o                        += -fno-stack-protector

cheers