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    SubjectRe: [PATCH] remove BUG() in possible but rare condition
    On Wed 11-04-12 16:02:19, Glauber Costa wrote:
    > On 04/11/2012 03:57 PM, Linus Torvalds wrote:
    > >On Wed, Apr 11, 2012 at 11:48 AM, Michal Hocko<> wrote:
    > >>
    > >>I am not familiar with the code much but a trivial call chain walk up to
    > >>write_dev_supers (in btrfs) shows that we do not check for the return value
    > >>from __getblk so we would nullptr and there might be more.
    > >>I guess these need some treat before the BUG might be removed, right?
    > >
    > >Well, realistically, isn't BUG() as bad as a NULL pointer dereference?
    > >
    > >Do you care about the exact message on the screen when your machine dies?
    > Not particular, but I don't see why (I might be wrong) it would
    > necessarily lead to a NULL pointer dereference.

    Ahh, OK scratch that. I have misread __getblk_slow which returns NULL
    only if grow_buffers returned with < 0 which doesn't happen for the
    allocation failure.

    Sorry about noise
    Michal Hocko
    SUSE Labs
    SUSE LINUX s.r.o.
    Lihovarska 1060/12
    190 00 Praha 9
    Czech Republic

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