Re: [PATCH v2] ARM: unwind: improve unwinders for noreturn case

From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: David Laight <David.Laight@aculab.com>,
	Jiangfeng Xiao <xiaojiangfeng@huawei.com>,
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Subject: Re: [PATCH v2] ARM: unwind: improve unwinders for noreturn case
Date: Fri, 22 Mar 2024 00:08:54 +0000	[thread overview]
Message-ID: <ZfzMFv3zmYY36l9u@shell.armlinux.org.uk> (raw)
In-Reply-To: <CAMj1kXG2EGvgGuV-K7h5qDVJeLMd5hkq8GzigzCRzh9Z8cgyWw@mail.gmail.com>

On Thu, Mar 21, 2024 at 11:43:41PM +0100, Ard Biesheuvel wrote:
> Given that this particular issue would just disappear if the compiler
> would just insert a BRK after the BL, I'd prefer to explore first
> whether we can get this fixed on the compiler side.

Arm32 doesn't have a BRK instruction. What would be appropriate after
the no-return BL would be OS specific.

Maybe a branch to "abort" would be a good idea though.

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