From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Thu, 19 Jun 2003 17:36:34 +0000 Subject: SCSI ERRORS triggered by BIO_VMERGE_BOUNDARY Message-Id: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Since we enabled block-layer-level merging of buffers via BIO_VMERGE_BOUNDARY (in asm-ia64/io.h), I started to notice SCSI errors on one of our machines (an rx5670 with 16GB of memory). If I set BIO_VMERGE_BOUNDARY to 0, the errors disappear. My suspicion is that something is wrong in the sba_iommu.c code with respect to block merging. Unfortunately, I won't be able to investigate this further at the moment, since I'm trying to get out a 2.5.72 patch and will be on vacation on and off over the next 2 weeks. One thing that would be interesting to know is whether similar SCSI errors show up on SN2 machines (assuming the SGI guys can get the latest 2.5 bits to boot, of course). This should tell us whether the bug is really in the I/O MMU or somewhere else. For reference, I attached a couple of sample error message below. Can someone look into this? --david Jun 19 06:31:15 magma kernel: SCSI error : <3 0 0 0> return code = 0x70000 Jun 19 06:31:15 magma kernel: end_request: I/O error, dev sda, sector 2573060 Jun 19 06:31:15 magma kernel: SCSI error : <3 0 0 0> return code = 0x70000 Jun 19 06:31:15 magma kernel: end_request: I/O error, dev sda, sector 2573068 Jun 19 06:31:15 magma kernel: SCSI error : <3 0 0 0> return code = 0x70000 Jun 19 06:31:15 magma kernel: end_request: I/O error, dev sda, sector 2573076