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Date:   Sat, 27 Oct 2018 19:08:58 +0800
From:   Baoquan He <bhe@redhat.com>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Petr Tesarik <ptesarik@suse.cz>, lijiang <lijiang@redhat.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        kexec@lists.infradead.org, mingo@redhat.com, tglx@linutronix.de,
        dyoung@redhat.com
Subject: Re: [PATCH] kdump, vmcoreinfo: Export sme_me_mask value to vmcoreinfo
Message-ID: <20181027110858.GB14493@MiWiFi-R3L-srv>
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On 10/27/18 at 12:12pm, Borislav Petkov wrote:
> On Sat, Oct 27, 2018 at 05:39:17PM +0800, Baoquan He wrote:
> > Not very sure about this, we have arch_crash_save_vmcoreinfo() in
> > arch/x86/kernel/machine_kexec_64.c to export arch-specific stuffs
> > outside. Is there any special reason about a mask in one architecture
> > when expose it out?
> 
> Yes, we don't export random arch-specific details to the outside which
> we then cannot change later. So vmcoreinfo needs to define its own.

OK, then it's fine to get the bit number, e.g calling
find_first_bit(sme_me_mask, BITS_PER_LONG), and export it to
vmcoreinfo. Thanks.