From a1a15ac5f9aeee521c048a88fc1aec848e623de7 Mon Sep 17 00:00:00 2001 From: Kris Shannon Date: Mon, 2 Mar 2009 19:47:37 +1100 Subject: Fix kernel NULL pointer dereference in xen-blkfront When booting Xen Dom0 on a pre-release 3.2.1 hypervisor the system Oopses on a "Unable to handle kernel NULL pointer dereference" in xenwatch. From the backtrace it looks like backend_changed is calling bdget_disk with a NULL pointer. Checking for NULL and returning ENODEV instead allows the kernel to boot. --- drivers/block/xen-blkfront.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index b6c8ce254359..8f905089b72b 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -977,6 +977,8 @@ static void backend_changed(struct xenbus_device *dev, break; case XenbusStateClosing: + if (info->gd == NULL) + xenbus_dev_fatal(dev, -ENODEV, "gd is NULL"); bd = bdget_disk(info->gd, 0); if (bd == NULL) xenbus_dev_fatal(dev, -ENODEV, "bdget failed"); -- cgit v1.2.3 From 5e18cfd04feca78cc08a6b8b71a60a610de81eaa Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 27 Feb 2009 08:10:26 +0100 Subject: cciss: remove 30 second initial timeout on controller reset Commit 5e4c91c84b194b26cf592779e451f4b5be777cba forgot to remove the initial sleep, get rid of it. Thanks to Randy Dunlap for spotting this error. Signed-off-by: Jens Axboe --- drivers/block/cciss.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c index b5a061114630..4f9b6d792017 100644 --- a/drivers/block/cciss.c +++ b/drivers/block/cciss.c @@ -3606,11 +3606,9 @@ static int __devinit cciss_init_one(struct pci_dev *pdev, if (cciss_hard_reset_controller(pdev) || cciss_reset_msi(pdev)) return -ENODEV; - /* Some devices (notably the HP Smart Array 5i Controller) - need a little pause here */ - schedule_timeout_uninterruptible(30*HZ); - - /* Now try to get the controller to respond to a no-op */ + /* Now try to get the controller to respond to a no-op. Some + devices (notably the HP Smart Array 5i Controller) need + up to 30 seconds to respond. */ for (i=0; i<30; i++) { if (cciss_noop(pdev) == 0) break; -- cgit v1.2.3 From a3941ec101a5ec54c1e929730afeb196441a171e Mon Sep 17 00:00:00 2001 From: Roel Kluin Date: Thu, 5 Mar 2009 08:03:53 +0100 Subject: loop: don't increment p->offset with (size_t) -EINVAL Upon a 'transfer error block' size is set to -EINVAL, but this becomes positive since size is unsigned: p->offset still gets incremented. Signed-off-by: Roel Kluin Signed-off-by: Jens Axboe --- drivers/block/loop.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index edbaac6c0573..bf0345577672 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -392,8 +392,7 @@ lo_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf, struct loop_device *lo = p->lo; struct page *page = buf->page; sector_t IV; - size_t size; - int ret; + int size, ret; ret = buf->ops->confirm(pipe, buf); if (unlikely(ret)) -- cgit v1.2.3 From 59247eaea50cc68cc6ce3d3fd3855f3301b65c96 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 6 Mar 2009 08:55:24 +0100 Subject: block: fix missing bio back/front segment size setting in blk_recount_segments() Commit 1e42807918d17e8c93bf14fbb74be84b141334c1 introduced a bug where we don't get front/back segment sizes in the bio in blk_recount_segments(). Fix this by tracking the back bio as well as the front bio in __blk_recalc_rq_segments(), this also cleans up the interface by getting rid of the segment size pointer passing. Tested-by: Thomas Gleixner Tested-by: Ingo Molnar Signed-off-by: Jens Axboe --- block/blk-merge.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-) diff --git a/block/blk-merge.c b/block/blk-merge.c index a104593e70c3..5a244f05360f 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -39,14 +39,13 @@ void blk_recalc_rq_sectors(struct request *rq, int nsect) } static unsigned int __blk_recalc_rq_segments(struct request_queue *q, - struct bio *bio, - unsigned int *seg_size_ptr) + struct bio *bio) { unsigned int phys_size; struct bio_vec *bv, *bvprv = NULL; int cluster, i, high, highprv = 1; unsigned int seg_size, nr_phys_segs; - struct bio *fbio; + struct bio *fbio, *bbio; if (!bio) return 0; @@ -87,26 +86,20 @@ new_segment: seg_size = bv->bv_len; highprv = high; } + bbio = bio; } - if (seg_size_ptr) - *seg_size_ptr = seg_size; + if (nr_phys_segs == 1 && seg_size > fbio->bi_seg_front_size) + fbio->bi_seg_front_size = seg_size; + if (seg_size > bbio->bi_seg_back_size) + bbio->bi_seg_back_size = seg_size; return nr_phys_segs; } void blk_recalc_rq_segments(struct request *rq) { - unsigned int seg_size = 0, phys_segs; - - phys_segs = __blk_recalc_rq_segments(rq->q, rq->bio, &seg_size); - - if (phys_segs == 1 && seg_size > rq->bio->bi_seg_front_size) - rq->bio->bi_seg_front_size = seg_size; - if (seg_size > rq->biotail->bi_seg_back_size) - rq->biotail->bi_seg_back_size = seg_size; - - rq->nr_phys_segments = phys_segs; + rq->nr_phys_segments = __blk_recalc_rq_segments(rq->q, rq->bio); } void blk_recount_segments(struct request_queue *q, struct bio *bio) @@ -114,7 +107,7 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio) struct bio *nxt = bio->bi_next; bio->bi_next = NULL; - bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio, NULL); + bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio); bio->bi_next = nxt; bio->bi_flags |= (1 << BIO_SEG_VALID); } -- cgit v1.2.3