From 6599a613105892ff62a81b265e842455f759c399 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 14 Oct 2021 14:19:16 -0700 Subject: drm/i915: Avoid bitwise vs logical OR warning in snb_wm_latency_quirk() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 2e70570656adfe1c5d9a29940faa348d5f132199 upstream. A new warning in clang points out a place in this file where a bitwise OR is being used with boolean types: drivers/gpu/drm/i915/intel_pm.c:3066:12: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical] changed = ilk_increase_wm_latency(dev_priv, dev_priv->wm.pri_latency, 12) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This construct is intentional, as it allows every one of the calls to ilk_increase_wm_latency() to occur (instead of short circuiting with logical OR) while still caring about the result of each call. To make this clearer to the compiler, use the '|=' operator to assign the result of each ilk_increase_wm_latency() call to changed, which keeps the meaning of the code the same but makes it obvious that every one of these calls is expected to happen. Link: https://github.com/ClangBuiltLinux/linux/issues/1473 Reported-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Suggested-by: Dávid Bolvanský Reviewed-by: Nick Desaulniers Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20211014211916.3550122-1-nathan@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_pm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/gpu') diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 81bd84f9156b..3e107e103d35 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2245,9 +2245,9 @@ static void snb_wm_latency_quirk(struct drm_device *dev) * The BIOS provided WM memory latency values are often * inadequate for high resolution displays. Adjust them. */ - changed = ilk_increase_wm_latency(dev_priv, dev_priv->wm.pri_latency, 12) | - ilk_increase_wm_latency(dev_priv, dev_priv->wm.spr_latency, 12) | - ilk_increase_wm_latency(dev_priv, dev_priv->wm.cur_latency, 12); + changed = ilk_increase_wm_latency(dev_priv, dev_priv->wm.pri_latency, 12); + changed |= ilk_increase_wm_latency(dev_priv, dev_priv->wm.spr_latency, 12); + changed |= ilk_increase_wm_latency(dev_priv, dev_priv->wm.cur_latency, 12); if (!changed) return; -- cgit v1.2.3 From 86951efaf8f5da11596d2880faab0d3aab22f094 Mon Sep 17 00:00:00 2001 From: Zhou Qingyang Date: Fri, 3 Dec 2021 00:17:36 +0800 Subject: drm/amdgpu: Fix a NULL pointer dereference in amdgpu_connector_lcd_native_mode() [ Upstream commit b220110e4cd442156f36e1d9b4914bb9e87b0d00 ] In amdgpu_connector_lcd_native_mode(), the return value of drm_mode_duplicate() is assigned to mode, and there is a dereference of it in amdgpu_connector_lcd_native_mode(), which will lead to a NULL pointer dereference on failure of drm_mode_duplicate(). Fix this bug add a check of mode. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_DRM_AMDGPU=m show no new warnings, and our static analyzer no longer warns about this code. Fixes: d38ceaf99ed0 ("drm/amdgpu: add core driver (v4)") Signed-off-by: Zhou Qingyang Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/gpu') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c index e1d4115bd673..80e3b41294e5 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c @@ -404,6 +404,9 @@ amdgpu_connector_lcd_native_mode(struct drm_encoder *encoder) native_mode->vdisplay != 0 && native_mode->clock != 0) { mode = drm_mode_duplicate(dev, native_mode); + if (!mode) + return NULL; + mode->type = DRM_MODE_TYPE_PREFERRED | DRM_MODE_TYPE_DRIVER; drm_mode_set_name(mode); @@ -418,6 +421,9 @@ amdgpu_connector_lcd_native_mode(struct drm_encoder *encoder) * simpler. */ mode = drm_cvt_mode(dev, native_mode->hdisplay, native_mode->vdisplay, 60, true, false, false); + if (!mode) + return NULL; + mode->type = DRM_MODE_TYPE_PREFERRED | DRM_MODE_TYPE_DRIVER; DRM_DEBUG_KMS("Adding cvt approximation of native panel mode %s\n", mode->name); } -- cgit v1.2.3