Dear Shaohua Li, In message <20160216201347.GB13119@xxxxxxxxxx> you wrote: > > > I think it is interesting that always the same RAID array gets > > kicked, and always the same disk. I cannot see any hardware > > problems, and a preventive replacement of the disk drive did not fix > > the problem. > > this doesn't like a md problem. I tend to agree, but so far I have not found any other test case that would trigger this problem. > Probably a dma address leak in the driver. To verify this, you can > do some IO against the raw disk (sdf/sdg) and check if you see the > 'swiotlb buffer is full' issue. At least sequentially reading the drive does not appear to have any effect; I've completely read it several times with no errors. > Did you really need iommu, eg if iommu=off works? This is a good idea; I will enable this setting next time the server crashed (probably next Sunday night). but then, is iommu=off not supposed to cause a performance degradation? Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@xxxxxxx Some people march to the beat of a different drummer. And some people tango! -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
