On 9/18/17 4:31 PM, Dave Chinner wrote: > On Mon, Sep 18, 2017 at 09:28:55AM -0600, Jens Axboe wrote: >> On 09/18/2017 09:27 AM, Christoph Hellwig wrote: >>> On Mon, Sep 18, 2017 at 08:26:05PM +0530, Abdul Haleem wrote: >>>> Hi, >>>> >>>> A warning is triggered from: >>>> >>>> file fs/iomap.c in function iomap_dio_rw >>>> >>>> if (ret) >>>> goto out_free_dio; >>>> >>>> ret = invalidate_inode_pages2_range(mapping, >>>> start >> PAGE_SHIFT, end >> PAGE_SHIFT); >>>>>> WARN_ON_ONCE(ret); >>>> ret = 0; >>>> >>>> inode_dio_begin(inode); >>> >>> This is expected and an indication of a problematic workload - which >>> may be triggered by a fuzzer. >> >> If it's expected, why don't we kill the WARN_ON_ONCE()? I get it all >> the time running xfstests as well. > > Because when a user reports a data corruption, the only evidence we > have that they are running an app that does something stupid is this > warning in their syslogs. Tracepoints are not useful for replacing > warnings about data corruption vectors being triggered. Is the full WARN_ON spew really helpful to us, though? Certainly the user has no idea what it means, and will come away terrified but none the wiser. Would a more informative printk_once() still give us the evidence without the ZOMG I THINK I OOPSED that a WARN_ON produces? Or do we want/need the backtrace? -Eric > It needs to be on by default, bu tI'm sure we can wrap it with > something like an xfs_alert_tag() type of construct so the tag can > be set in /proc/fs/xfs/panic_mask to suppress it if testers so > desire. > > Cheers, > > Dave. > -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
