From: Maxime Ripard <mripard@kernel.org>
To: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Thomas Zimmermann <tzimmermann@suse.de>,
David Airlie <airlied@gmail.com>,
Simona Vetter <simona@ffwll.ch>,
Andrzej Hajda <andrzej.hajda@intel.com>,
Neil Armstrong <neil.armstrong@linaro.org>,
Robert Foss <rfoss@kernel.org>,
Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
Jonas Karlman <jonas@kwiboo.se>,
Jernej Skrabec <jernej.skrabec@gmail.com>,
Jyri Sarha <jyri.sarha@iki.fi>,
Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Cc: Devarsh Thakkar <devarsht@ti.com>,
dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
Maxime Ripard <mripard@kernel.org>
Subject: [PATCH v2 03/28] drm/atomic_state_helper: Remove memset in __drm_atomic_helper_bridge_reset()
Date: Thu, 23 Apr 2026 12:18:16 +0200 [thread overview]
Message-ID: <20260423-drm-state-readout-v2-3-8549f87cb978@kernel.org> (raw)
In-Reply-To: <20260423-drm-state-readout-v2-0-8549f87cb978@kernel.org>
The general consensus is that reset helpers shouldn't call memset
directly because the object it initializes is supposed to have been
zeroed out.
Remove the memset call from
__drm_atomic_helper_bridge_reset() and document the expectation.
It should not have any impact on the current code base since there's
only two callers: drm_atomic_helper_bridge_reset() and
cdns-mhdp8546-core's cdns_mhdp_bridge_atomic_reset(), both allocating
the object using kzalloc_obj().
Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
drivers/gpu/drm/drm_atomic_state_helper.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
index c7eb3ce8c282..1a6f55329fee 100644
--- a/drivers/gpu/drm/drm_atomic_state_helper.c
+++ b/drivers/gpu/drm/drm_atomic_state_helper.c
@@ -952,15 +952,16 @@ EXPORT_SYMBOL(drm_atomic_helper_bridge_destroy_state);
* @state: bridge state to initialize
*
* Initializes the bridge state to default values. This is meant to be called
* by the bridge &drm_bridge_funcs.atomic_reset hook for bridges that subclass
* the bridge state.
+ *
+ * The object @state points to is assumed to have been initialized to zero.
*/
void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge,
struct drm_bridge_state *state)
{
- memset(state, 0, sizeof(*state));
__drm_atomic_helper_private_obj_create_state(&bridge->base, &state->base);
state->bridge = bridge;
}
EXPORT_SYMBOL(__drm_atomic_helper_bridge_reset);
--
2.53.0
next prev parent reply other threads:[~2026-04-23 10:18 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-23 10:18 [PATCH v2 00/28] drm: Implement state readout support Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 01/28] drm/atomic: Fix unused but set warning in state iterator macros Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 02/28] drm/atomic_helper: Skip over NULL private_obj pointers Maxime Ripard
2026-04-23 10:18 ` Maxime Ripard [this message]
2026-04-23 10:18 ` [PATCH v2 04/28] drm/atomic: Convert drm_priv_to_bridge_state to container_of_const Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 05/28] drm/atomic: Add drm_private_obj name Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 06/28] drm/bridge: Add drm_private_obj_is_bridge() Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 07/28] drm/bridge: Implement atomic_print_state Maxime Ripard
2026-04-24 14:13 ` Jani Nikula
2026-04-23 10:18 ` [PATCH v2 08/28] drm/atomic: Export drm_atomic_*_print_state Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 09/28] drm/atomic: Only call atomic_destroy_state on a !NULL pointer Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 10/28] drm/atomic_sro: Create drm_atomic_sro_state container Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 11/28] drm/atomic_sro: Create kernel parameter to force or disable readout Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 12/28] drm/atomic_sro: Add atomic state readout infrastructure Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 13/28] drm/atomic_sro: Add function to install state into drm objects Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 14/28] drm/atomic_sro: Create documentation Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 15/28] drm/bridge: Handle bridges with hardware state readout Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 16/28] drm/mode_config: Read out hardware state in drm_mode_config_create_state Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 17/28] drm/atomic_sro: Provide helpers to implement hardware state readout Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 18/28] drm/atomic_helper: Pass nonblock to commit_tail Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 19/28] drm/atomic_helper: Compare actual and readout states once the commit is done Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 20/28] drm/atomic_state_helper: Provide comparison macros Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 21/28] drm/atomic_state_helper: Provide atomic_compare_state helpers Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 22/28] drm/encoder: Create atomic_sro_get_current_crtc hook Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 23/28] drm/bridge: display-connector: Implement readout support Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 24/28] drm/bridge_connector: Implement hw readout for connector Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 25/28] drm/tidss: dispc: Improve mode checking logs Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 26/28] drm/tidss: Implement readout support Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 27/28] drm/tidss: encoder: Implement atomic_sro_get_current_crtc Maxime Ripard
2026-04-23 10:18 ` [PATCH v2 28/28] drm/bridge: sii902x: Implement hw state readout Maxime Ripard
-- strict thread matches above, loose matches on Subject: below --
2026-04-23 10:06 [PATCH v2 00/28] drm: Implement state readout support Maxime Ripard
2026-04-23 10:06 ` [PATCH v2 03/28] drm/atomic_state_helper: Remove memset in __drm_atomic_helper_bridge_reset() Maxime Ripard
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