| Message ID | 1416215672-31554-1-git-send-email-ckeepax@opensource.wolfsonmicro.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Nov 17, 2014 at 09:14:31AM +0000, Charles Keepax wrote: > We can only use page_address on memory that has been mapped using kmap, > when the buffer passed to the SPI has been allocated by vmalloc the page > has not necessarily been mapped through kmap. This means sometimes > page_address will return NULL causing the pointer we pass to sg_set_buf > to be invalid. Applied, thanks.
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ebcb33d..50f20f2 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -615,13 +615,13 @@ static int spi_map_buf(struct spi_master *master, struct device *dev, sg_free_table(sgt); return -ENOMEM; } - sg_buf = page_address(vm_page) + - ((size_t)buf & ~PAGE_MASK); + sg_set_page(&sgt->sgl[i], vm_page, + min, offset_in_page(buf)); } else { sg_buf = buf; + sg_set_buf(&sgt->sgl[i], sg_buf, min); } - sg_set_buf(&sgt->sgl[i], sg_buf, min); buf += min; len -= min;
We can only use page_address on memory that has been mapped using kmap, when the buffer passed to the SPI has been allocated by vmalloc the page has not necessarily been mapped through kmap. This means sometimes page_address will return NULL causing the pointer we pass to sg_set_buf to be invalid. As we only call page_address so that we can pass a virtual address to sg_set_buf which will then immediately call virt_to_page on it, fix this by calling sg_set_page directly rather then relying on the sg_set_buf helper. Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> --- drivers/spi/spi.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-)