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Message-ID: <06400bab5a734666bc5b9565e151eb477f9831b7.camel@ozlabs.org>
Subject: Re: [PATCH 1/6] powerpc/spufs: simplify spufs core dumping
From:   Jeremy Kerr <jk@ozlabs.org>
To:     Christoph Hellwig <hch@lst.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Michael Ellerman <mpe@ellerman.id.au>
Cc:     Arnd Bergmann <arnd@arndb.de>, linuxppc-dev@lists.ozlabs.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Tue, 07 Apr 2020 08:01:16 +0800
In-Reply-To: <20200406120312.1150405-2-hch@lst.de>
References: <20200406120312.1150405-1-hch@lst.de>
         <20200406120312.1150405-2-hch@lst.de>
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Hi Christoph,

> Replace the coredump ->read method with a ->dump method that must call
> dump_emit itself.  That way we avoid a buffer allocation an messing with
> set_fs() to call into code that is intended to deal with user buffers.
> For the ->get case we can now use a small on-stack buffer and avoid
> memory allocations as well.

That looks much better, thanks!

Reviewed-by: Jeremy Kerr <jk@ozlabs.org>

However, I no longer have access to hardware to test this on. Michael,
are the coredump tests in spufs-testsuite still alive?

Cheers,


Jeremy