Messages in this thread | | | Date | Tue, 10 May 2011 09:44:28 +0200 | From | Jens Axboe <> | Subject | Re: [PATCH 1/2] cdrom: always check_disk_change() on open |
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On 2011-05-10 08:42, Amit Shah wrote: > On (Fri) 29 Apr 2011 [10:15:50], Jens Axboe wrote: >> On 2011-04-29 08:57, Amit Shah wrote: >>> On (Wed) 06 Apr 2011 [05:20:09], Tejun Heo wrote: >>>> cdrom_open() called check_disk_change() after the rest of open path >>>> succeeded which leads to the following bizarre behavior. >>>> >>>> * After media change, if the device opened without O_NONBLOCK, >>>> open_for_data() naturally fails with -ENOMEDIA and >>>> check_disk_change() is never called. The media is known to be gone >>>> and the open failure makes it obvious to the userland but device >>>> invalidation never happens. >>>> >>>> * But if the device is opened with O_NONBLOCK, all the checks are >>>> bypassed and cdrom_open() doesn't notice that the media is not there >>>> and check_disk_change() is called and invalidation happens. >>>> >>>> There's nothing to be gained by avoiding calling check_disk_change() >>>> on open failure. Common cases end up calling check_disk_change() >>>> anyway. All we get is inconsistent behavior. >>>> >>>> Fix it by moving check_disk_change() invocation to the top of >>>> cdrom_open() so that it always gets called regardless of how the rest >>>> of open proceeds. >>>> >>>> Signed-off-by: Tejun Heo <tj@kernel.org> >>>> Reported-by: Amit Shah <amit.shah@redhat.com> >>>> Tested-by: Amit Shah <amit.shah@redhat.com> >>> >>> Ping? >>> >>> Also, please mark this for stable-2.6.38. >> >> Done, added for 2.6.39 and marked stable for 2.6.38. > > Ping again. Don't see this yet in Linus's git tree.
It was added for 2.6.40 and marked for stable.
-- Jens Axboe
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