From: Jérôme Glisse <jglisse@xxxxxxxxxx> For pages that were retained via get_user_pages*(), release those pages via the new put_user_page*() routines, instead of via put_page(). This is part a tree-wide conversion, as described in commit fc1d8e7cca2d ("mm: introduce put_user_page*(), placeholder versions"). Changes from Jérôme's original patch: * Changed a WARN_ON to a BUG_ON. Signed-off-by: Jérôme Glisse <jglisse@xxxxxxxxxx> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx> Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx Cc: linux-fsdevel@xxxxxxxxxxxxxxx Cc: linux-block@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: Jan Kara <jack@xxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Johannes Thumshirn <jthumshirn@xxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: Ming Lei <ming.lei@xxxxxxxxxx> Cc: Dave Chinner <david@xxxxxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Boaz Harrosh <boaz@xxxxxxxxxxxxx> Cc: Miklos Szeredi <miklos@xxxxxxxxxx> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: Stefan Hajnoczi <stefanha@xxxxxxxxxx> --- drivers/vhost/scsi.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index a9caf1bc3c3e..282565ab5e3f 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -329,11 +329,11 @@ static void vhost_scsi_release_cmd(struct se_cmd *se_cmd) if (tv_cmd->tvc_sgl_count) { for (i = 0; i < tv_cmd->tvc_sgl_count; i++) - put_page(sg_page(&tv_cmd->tvc_sgl[i])); + put_user_page(sg_page(&tv_cmd->tvc_sgl[i])); } if (tv_cmd->tvc_prot_sgl_count) { for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++) - put_page(sg_page(&tv_cmd->tvc_prot_sgl[i])); + put_user_page(sg_page(&tv_cmd->tvc_prot_sgl[i])); } vhost_scsi_put_inflight(tv_cmd->inflight); @@ -630,6 +630,13 @@ vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd, size_t offset; unsigned int npages = 0; + /* + * Here in all cases we should have an IOVEC which use GUP. If that is + * not the case then we will wrongly call put_user_page() and the page + * refcount will go wrong (this is in vhost_scsi_release_cmd()) + */ + WARN_ON(!iov_iter_get_pages_use_gup(iter)); + bytes = iov_iter_get_pages(iter, pages, LONG_MAX, VHOST_SCSI_PREALLOC_UPAGES, &offset); /* No pages were pinned */ @@ -681,7 +688,7 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write, while (p < sg) { struct page *page = sg_page(p++); if (page) - put_page(page); + put_user_page(page); } return ret; } -- 2.22.0