Here, If devm_ioremap_nocache will fail. It will return NULL. Kernel can run into a NULL-pointer dereference. This error check will avoid NULL pointer dereference.
Signed-off-by: Arvind Yadav <arvind.yadav...@gmail.com> --- drivers/gpu/drm/sti/sti_vtac.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/sti/sti_vtac.c b/drivers/gpu/drm/sti/sti_vtac.c index cf7fe8a..dd749e9 100644 --- a/drivers/gpu/drm/sti/sti_vtac.c +++ b/drivers/gpu/drm/sti/sti_vtac.c @@ -191,6 +191,10 @@ static int sti_vtac_probe(struct platform_device *pdev) if (res) { vtac->phy_regs = devm_ioremap_nocache(dev, res->start, resource_size(res)); + if (!vtac->phy_regs) { + DRM_ERROR("failed to remap I/O memory\n"); + return -ENOMEM; + } sti_vtac_tx_set_config(vtac); } else { -- 1.7.9.5