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Subject: Re: [PATCH v3] IB/sa: Resolving use-after-free in ib_nl_send_msg
To:     Jason Gunthorpe <jgg@ziepe.ca>
Cc:     Leon Romanovsky <leon@kernel.org>, linux-kernel@vger.kernel.org,
        linux-rdma@vger.kernel.org, Kaike Wan <kaike.wan@intel.com>,
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        Srinivas Eeda <srinivas.eeda@oracle.com>,
        Rama Nichanamatlu <rama.nichanamatlu@oracle.com>,
        Doug Ledford <dledford@redhat.com>
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From:   Divya Indi <divya.indi@oracle.com>
Message-ID: <3770b85e-c684-f534-d6d5-84cf0874e485@oracle.com>
Date:   Fri, 19 Jun 2020 17:43:14 -0700
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Hi Jason,

Thanks for taking the time to review!

On 6/17/20 11:24 AM, Jason Gunthorpe wrote:
> On Tue, Jun 16, 2020 at 10:56:53AM -0700, Divya Indi wrote:
>> The other option might be to use GFP_NOWAIT conditionally ie
>> (only use GFP_NOWAIT when GFP_ATOMIC is not specified in gfp_mask else
>> use GFP_ATOMIC). Eventual goal being to not have a blocking memory allocation.
> This is probably safest for now, unless you can audit all callers and
> see if they can switch to GFP_NOWAIT as well

At present the callers with GFP_ATOMIC appear to be ipoib. Might not be
feasible to change them all to GFP_NOWAIT. 

Will incorporate the review comments and send out v3 early next week.

Thanks,
Divya

>
> Jason