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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Anton Ivanov <anton.ivanov@cambridgegreys.com>,
        Peter Zijlstra <peterz@infradead.org>,
        John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ankur Arora <ankur.a.arora@oracle.com>,
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        dave.hansen@linux.intel.com, hpa@zytor.com, mingo@redhat.com,
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        raghavendra.kt@amd.com, boris.ostrovsky@oracle.com,
        konrad.wilk@oracle.com, jgross@suse.com, andrew.cooper3@citrix.com,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        linux-m68k@lists.linux-m68k.org,
        Richard Weinberger <richard@nod.at>,
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        linux-um@lists.infradead.org, Brian Cain <bcain@quicinc.com>,
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        Richard Henderson <richard.henderson@linaro.org>,
        Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
        Matt Turner <mattst88@gmail.com>, linux-alpha@vger.kernel.org
Subject: Re: Arches that don't support PREEMPT
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Date:   Tue, 19 Sep 2023 17:17:23 +0200
Message-ID: <87y1h2ur98.ffs@tglx>
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On Tue, Sep 19 2023 at 15:21, Anton Ivanov wrote:
> On 19/09/2023 14:42, Peter Zijlstra wrote:
>> If you're working on one of them, then surely it's a simple matter of
>> working on adding CONFIG_PREEMPT support :-)
>
> In the case of UML adding preempt will be quite difficult. I looked at
> this a few years back.

What's so difficult about it?

Thanks,

        tglx