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Date:   Thu, 27 Apr 2023 12:53:04 +0200
From:   Heiko Carstens <hca@linux.ibm.com>
To:     Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-s390@vger.kernel.org, frankja@linux.ibm.com,
        borntraeger@de.ibm.com, nrb@linux.ibm.com, nsg@linux.ibm.com,
        seiden@linux.ibm.com, jgg@nvidia.com
Subject: Re: [PATCH v2 1/1] KVM: s390: fix race in gmap_make_secure
Message-ID: <ZEpUEF7H86E9vVfS@osiris>
References: <20230426134834.35199-1-imbrenda@linux.ibm.com>
 <20230426134834.35199-2-imbrenda@linux.ibm.com>
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On Wed, Apr 26, 2023 at 03:48:34PM +0200, Claudio Imbrenda wrote:
> This patch fixes a potential race in gmap_make_secure and removes the
> last user of follow_page without FOLL_GET.
> 
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
> Fixes: 214d9bbcd3a6 ("s390/mm: provide memory management functions for protected KVM guests")
> ---
>  arch/s390/kernel/uv.c | 32 +++++++++++---------------------
>  1 file changed, 11 insertions(+), 21 deletions(-)

It would be helpful if this would be a bit more descriptive. "Fix
race" is not very helpful :)

What race does this fix?
When can this happen?
What are the consequences if the race window is being hit?