diff options
author | Tony Battersby <tonyb@cybernetics.com> | 2008-02-05 18:36:10 +0300 |
---|---|---|
committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2008-02-08 03:02:44 +0300 |
commit | 4d2de3a50ce19af2008a90636436a1bf5b3b697b (patch) | |
tree | 7bf2d1974e54567cba53f258ccfaaa8d9922319a /drivers/scsi/aacraid | |
parent | 76d78300a6eb8b7f08e47703b7e68a659ffc2053 (diff) | |
download | linux-4d2de3a50ce19af2008a90636436a1bf5b3b697b.tar.xz |
[SCSI] fix BUG when sum(scatterlist) > bufflen
When sending a SCSI command to a tape drive via the SCSI Generic (sg)
driver, if the command has a data transfer length more than
scatter_elem_sz (32 KB default) and not a multiple of 512, then I either
hit BUG_ON(!valid_dma_direction(direction)) in dma_unmap_sg() or else
the command never completes (depending on the LLDD).
When constructing scatterlists, the sg driver rounds up the scatterlist
element sizes to be a multiple of 512. This can result in
sum(scatterlist lengths) > bufflen. In this case, scsi_req_map_sg()
incorrectly sets bio->bi_size to sum(scatterlist lengths) rather than to
bufflen. When the command completes, req_bio_endio() detects that
bio->bi_size != 0, and so it doesn't call bio_endio(). This causes the
command to be resubmitted, resulting in BUG_ON or the command never
completing.
This patch makes scsi_req_map_sg() set bio->bi_size to bufflen rather
than to sum(scatterlist lengths), which fixes the problem.
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers/scsi/aacraid')
0 files changed, 0 insertions, 0 deletions