On Fri, 25 Jan 2013, Theodore Ts'o wrote: > Date: Fri, 25 Jan 2013 10:09:48 -0500 > From: Theodore Ts'o <tytso@xxxxxxx> > To: Lukáš Czerner <lczerner@xxxxxxxxxx> > Cc: linux-ext4@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 1/2] ext4: call WARN_ON after the debug message > > On Fri, Jan 25, 2013 at 10:22:44AM +0100, Lukáš Czerner wrote: > > > > we can get the EIO error from ext4_map_blocks not only in the case > > of hardware error. The extent tree might not be in consistent state, > > or we could even ask for blocks outside the file system itself (I > > believe I've seen this before) and I think that in those cases it > > might be worth to all WARN_ON. > > Sure, but in those cases, the file system is corrupt, and we should > have thrown an ext4_error() in ext4_map_blocks(). The point is that a > WARN_ON is only useful if there is a potential programming bug. If we > know for sure that it's caused by a file system corruption, then we > don't want to throw a WARN_ON. > > Even if there is a kerneloops.org replacement --- in fact, especially > if there is kerneloops.org replacement --- we only want to throw > WARN_ON's in cases where it's just a pedestrian file system > corruption. Otherwise we'll end up wasting a lot of time chasing down > something which was caused by a hardware error, and needing to calm > down users (and breathless, spectacularizing, irresponsible journalism > from web sites such as Phoronix). > > - Ted Fair enough, I'll remove the WARN_ON and use ext4_warning() instead of ext4_msg. Thanks! -Lukas
