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Subject: Re: [PATCH 4/6] s390: add system call to run tasks with modified
 branch prediction
To: Martin Schwidefsky <schwidefsky@de.ibm.com>,
        linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org,
        kvm@vger.kernel.org
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jon Masters <jcm@redhat.com>,
        Marcus Meissner <meissner@suse.de>,
        Jiri Kosina <jkosina@suse.cz>
References: <1516182519-10623-1-git-send-email-schwidefsky@de.ibm.com>
 <1516182519-10623-5-git-send-email-schwidefsky@de.ibm.com>
From: Florian Weimer <fweimer@redhat.com>
Message-ID: <5bda76be-0fec-8165-20bf-5cd8e51e955a@redhat.com>
Date: Wed, 17 Jan 2018 11:03:03 +0100
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On 01/17/2018 10:48 AM, Martin Schwidefsky wrote:
>          rc = syscall(__NR_s390_modify_bp);
>          if (rc) {
>                  perror("s390_modify_bp");
>                  exit(EXIT_FAILURE);
>          }

Isn't this traditionally done through personality or prctl?

This looks like something other architectures may want as well.

Thanks,
Florian