The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 6d849ff573722afcf5508d2800017bdd40f27eb9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025120156-taunt-paternity-aa16@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6d849ff573722afcf5508d2800017bdd40f27eb9 Mon Sep 17 00:00:00 2001
From: Biju Das <biju.das.jz(a)bp.renesas.com>
Date: Tue, 18 Nov 2025 12:39:25 +0000
Subject: [PATCH] can: rcar_canfd: Fix CAN-FD mode as default
The commit 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting")
has aligned with the flow mentioned in the hardware manual for all SoCs
except R-Car Gen3 and RZ/G2L SoCs. On R-Car Gen4 and RZ/G3E SoCs, due to
the wrong logic in the commit[1] sets the default mode to FD-Only mode
instead of CAN-FD mode.
This patch sets the CAN-FD mode as the default for all SoCs by dropping
the rcar_canfd_set_mode() as some SoC requires mode setting in global
reset mode, and the rest of the SoCs in channel reset mode and update the
rcar_canfd_reset_controller() to take care of these constraints. Moreover,
the RZ/G3E and R-Car Gen4 SoCs support 3 modes compared to 2 modes on the
R-Car Gen3. Use inverted logic in rcar_canfd_reset_controller() to
simplify the code later to support FD-only mode.
[1]
commit 45721c406dcf ("can: rcar_canfd: Add support for r8a779a0 SoC")
Fixes: 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting")
Cc: stable(a)vger.kernel.org
Signed-off-by: Biju Das <biju.das.jz(a)bp.renesas.com>
Link: https://patch.msgid.link/20251118123926.193445-1-biju.das.jz@bp.renesas.com
Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de>
diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index 45d36adb51b7..4c0d7d26df9f 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -709,6 +709,11 @@ static void rcar_canfd_set_bit_reg(void __iomem *addr, u32 val)
rcar_canfd_update(val, val, addr);
}
+static void rcar_canfd_clear_bit_reg(void __iomem *addr, u32 val)
+{
+ rcar_canfd_update(val, 0, addr);
+}
+
static void rcar_canfd_update_bit_reg(void __iomem *addr, u32 mask, u32 val)
{
rcar_canfd_update(mask, val, addr);
@@ -755,25 +760,6 @@ static void rcar_canfd_set_rnc(struct rcar_canfd_global *gpriv, unsigned int ch,
rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLCFG(w), rnc);
}
-static void rcar_canfd_set_mode(struct rcar_canfd_global *gpriv)
-{
- if (gpriv->info->ch_interface_mode) {
- u32 ch, val = gpriv->fdmode ? RCANFD_GEN4_FDCFG_FDOE
- : RCANFD_GEN4_FDCFG_CLOE;
-
- for_each_set_bit(ch, &gpriv->channels_mask,
- gpriv->info->max_channels)
- rcar_canfd_set_bit_reg(&gpriv->fcbase[ch].cfdcfg, val);
- } else {
- if (gpriv->fdmode)
- rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG,
- RCANFD_GRMCFG_RCMC);
- else
- rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG,
- RCANFD_GRMCFG_RCMC);
- }
-}
-
static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
{
struct device *dev = &gpriv->pdev->dev;
@@ -806,6 +792,16 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
/* Reset Global error flags */
rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0x0);
+ /* Set the controller into appropriate mode */
+ if (!gpriv->info->ch_interface_mode) {
+ if (gpriv->fdmode)
+ rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG,
+ RCANFD_GRMCFG_RCMC);
+ else
+ rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG,
+ RCANFD_GRMCFG_RCMC);
+ }
+
/* Transition all Channels to reset mode */
for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
rcar_canfd_clear_bit(gpriv->base,
@@ -823,10 +819,23 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
dev_dbg(dev, "channel %u reset failed\n", ch);
return err;
}
- }
- /* Set the controller into appropriate mode */
- rcar_canfd_set_mode(gpriv);
+ /* Set the controller into appropriate mode */
+ if (gpriv->info->ch_interface_mode) {
+ /* Do not set CLOE and FDOE simultaneously */
+ if (!gpriv->fdmode) {
+ rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_FDOE);
+ rcar_canfd_set_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_CLOE);
+ } else {
+ rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_FDOE);
+ rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_CLOE);
+ }
+ }
+ }
return 0;
}
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x eb76d0f5553575599561010f24c277cc5b31d003
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025120119-quake-universal-d896@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From eb76d0f5553575599561010f24c277cc5b31d003 Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann(a)suse.de>
Date: Wed, 5 Nov 2025 17:14:49 +0100
Subject: [PATCH] drm, fbcon, vga_switcheroo: Avoid race condition in fbcon
setup
Protect vga_switcheroo_client_fb_set() with console lock. Avoids OOB
access in fbcon_remap_all(). Without holding the console lock the call
races with switching outputs.
VGA switcheroo calls fbcon_remap_all() when switching clients. The fbcon
function uses struct fb_info.node, which is set by register_framebuffer().
As the fb-helper code currently sets up VGA switcheroo before registering
the framebuffer, the value of node is -1 and therefore not a legal value.
For example, fbcon uses the value within set_con2fb_map() [1] as an index
into an array.
Moving vga_switcheroo_client_fb_set() after register_framebuffer() can
result in VGA switching that does not switch fbcon correctly.
Therefore move vga_switcheroo_client_fb_set() under fbcon_fb_registered(),
which already holds the console lock. Fbdev calls fbcon_fb_registered()
from within register_framebuffer(). Serializes the helper with VGA
switcheroo's call to fbcon_remap_all().
Although vga_switcheroo_client_fb_set() takes an instance of struct fb_info
as parameter, it really only needs the contained fbcon state. Moving the
call to fbcon initialization is therefore cleaner than before. Only amdgpu,
i915, nouveau and radeon support vga_switcheroo. For all other drivers,
this change does nothing.
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Link: https://elixir.bootlin.com/linux/v6.17/source/drivers/video/fbdev/core/fbco… # [1]
Fixes: 6a9ee8af344e ("vga_switcheroo: initial implementation (v15)")
Acked-by: Javier Martinez Canillas <javierm(a)redhat.com>
Acked-by: Alex Deucher <alexander.deucher(a)amd.com>
Cc: dri-devel(a)lists.freedesktop.org
Cc: nouveau(a)lists.freedesktop.org
Cc: amd-gfx(a)lists.freedesktop.org
Cc: linux-fbdev(a)vger.kernel.org
Cc: <stable(a)vger.kernel.org> # v2.6.34+
Link: https://patch.msgid.link/20251105161549.98836-1-tzimmermann@suse.de
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 11a5b60cb9ce..0b3ee008523d 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -31,9 +31,7 @@
#include <linux/console.h>
#include <linux/export.h>
-#include <linux/pci.h>
#include <linux/sysrq.h>
-#include <linux/vga_switcheroo.h>
#include <drm/drm_atomic.h>
#include <drm/drm_drv.h>
@@ -566,11 +564,6 @@ EXPORT_SYMBOL(drm_fb_helper_release_info);
*/
void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
{
- struct fb_info *info = fb_helper->info;
- struct device *dev = info->device;
-
- if (dev_is_pci(dev))
- vga_switcheroo_client_fb_set(to_pci_dev(dev), NULL);
unregister_framebuffer(fb_helper->info);
}
EXPORT_SYMBOL(drm_fb_helper_unregister_info);
@@ -1632,7 +1625,6 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper)
struct drm_client_dev *client = &fb_helper->client;
struct drm_device *dev = fb_helper->dev;
struct drm_fb_helper_surface_size sizes;
- struct fb_info *info;
int ret;
if (drm_WARN_ON(dev, !dev->driver->fbdev_probe))
@@ -1653,12 +1645,6 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper)
strcpy(fb_helper->fb->comm, "[fbcon]");
- info = fb_helper->info;
-
- /* Set the fb info for vgaswitcheroo clients. Does nothing otherwise. */
- if (dev_is_pci(info->device))
- vga_switcheroo_client_fb_set(to_pci_dev(info->device), info);
-
return 0;
}
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 9bd3c3814b5c..e7e07eb2142e 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -66,6 +66,7 @@
#include <linux/string.h>
#include <linux/kd.h>
#include <linux/panic.h>
+#include <linux/pci.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/fb.h>
@@ -78,6 +79,7 @@
#include <linux/interrupt.h>
#include <linux/crc32.h> /* For counting font checksums */
#include <linux/uaccess.h>
+#include <linux/vga_switcheroo.h>
#include <asm/irq.h>
#include "fbcon.h"
@@ -2899,6 +2901,9 @@ void fbcon_fb_unregistered(struct fb_info *info)
console_lock();
+ if (info->device && dev_is_pci(info->device))
+ vga_switcheroo_client_fb_set(to_pci_dev(info->device), NULL);
+
fbcon_registered_fb[info->node] = NULL;
fbcon_num_registered_fb--;
@@ -3032,6 +3037,10 @@ static int do_fb_registered(struct fb_info *info)
}
}
+ /* Set the fb info for vga_switcheroo clients. Does nothing otherwise. */
+ if (info->device && dev_is_pci(info->device))
+ vga_switcheroo_client_fb_set(to_pci_dev(info->device), info);
+
return ret;
}
The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 6d849ff573722afcf5508d2800017bdd40f27eb9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025120155-wrench-aching-b242@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6d849ff573722afcf5508d2800017bdd40f27eb9 Mon Sep 17 00:00:00 2001
From: Biju Das <biju.das.jz(a)bp.renesas.com>
Date: Tue, 18 Nov 2025 12:39:25 +0000
Subject: [PATCH] can: rcar_canfd: Fix CAN-FD mode as default
The commit 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting")
has aligned with the flow mentioned in the hardware manual for all SoCs
except R-Car Gen3 and RZ/G2L SoCs. On R-Car Gen4 and RZ/G3E SoCs, due to
the wrong logic in the commit[1] sets the default mode to FD-Only mode
instead of CAN-FD mode.
This patch sets the CAN-FD mode as the default for all SoCs by dropping
the rcar_canfd_set_mode() as some SoC requires mode setting in global
reset mode, and the rest of the SoCs in channel reset mode and update the
rcar_canfd_reset_controller() to take care of these constraints. Moreover,
the RZ/G3E and R-Car Gen4 SoCs support 3 modes compared to 2 modes on the
R-Car Gen3. Use inverted logic in rcar_canfd_reset_controller() to
simplify the code later to support FD-only mode.
[1]
commit 45721c406dcf ("can: rcar_canfd: Add support for r8a779a0 SoC")
Fixes: 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting")
Cc: stable(a)vger.kernel.org
Signed-off-by: Biju Das <biju.das.jz(a)bp.renesas.com>
Link: https://patch.msgid.link/20251118123926.193445-1-biju.das.jz@bp.renesas.com
Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de>
diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index 45d36adb51b7..4c0d7d26df9f 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -709,6 +709,11 @@ static void rcar_canfd_set_bit_reg(void __iomem *addr, u32 val)
rcar_canfd_update(val, val, addr);
}
+static void rcar_canfd_clear_bit_reg(void __iomem *addr, u32 val)
+{
+ rcar_canfd_update(val, 0, addr);
+}
+
static void rcar_canfd_update_bit_reg(void __iomem *addr, u32 mask, u32 val)
{
rcar_canfd_update(mask, val, addr);
@@ -755,25 +760,6 @@ static void rcar_canfd_set_rnc(struct rcar_canfd_global *gpriv, unsigned int ch,
rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLCFG(w), rnc);
}
-static void rcar_canfd_set_mode(struct rcar_canfd_global *gpriv)
-{
- if (gpriv->info->ch_interface_mode) {
- u32 ch, val = gpriv->fdmode ? RCANFD_GEN4_FDCFG_FDOE
- : RCANFD_GEN4_FDCFG_CLOE;
-
- for_each_set_bit(ch, &gpriv->channels_mask,
- gpriv->info->max_channels)
- rcar_canfd_set_bit_reg(&gpriv->fcbase[ch].cfdcfg, val);
- } else {
- if (gpriv->fdmode)
- rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG,
- RCANFD_GRMCFG_RCMC);
- else
- rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG,
- RCANFD_GRMCFG_RCMC);
- }
-}
-
static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
{
struct device *dev = &gpriv->pdev->dev;
@@ -806,6 +792,16 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
/* Reset Global error flags */
rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0x0);
+ /* Set the controller into appropriate mode */
+ if (!gpriv->info->ch_interface_mode) {
+ if (gpriv->fdmode)
+ rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG,
+ RCANFD_GRMCFG_RCMC);
+ else
+ rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG,
+ RCANFD_GRMCFG_RCMC);
+ }
+
/* Transition all Channels to reset mode */
for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
rcar_canfd_clear_bit(gpriv->base,
@@ -823,10 +819,23 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
dev_dbg(dev, "channel %u reset failed\n", ch);
return err;
}
- }
- /* Set the controller into appropriate mode */
- rcar_canfd_set_mode(gpriv);
+ /* Set the controller into appropriate mode */
+ if (gpriv->info->ch_interface_mode) {
+ /* Do not set CLOE and FDOE simultaneously */
+ if (!gpriv->fdmode) {
+ rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_FDOE);
+ rcar_canfd_set_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_CLOE);
+ } else {
+ rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_FDOE);
+ rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg,
+ RCANFD_GEN4_FDCFG_CLOE);
+ }
+ }
+ }
return 0;
}