FAILED: patch "[PATCH] fbdev: kyro: Release WC setup on registration failure" failed to apply to 5.15-stable tree

FAILED: patch "[PATCH] fbdev: kyro: Release WC setup on registration failure" failed to apply to 5.15-stable tree

[Sasha Levin]

The patch below does not apply to the 5.15-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@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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x d3bc005a62945aec57059201092b12b7c955e5a7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107060509-failed-5.15-d3bc005a6294@kernel.org' --subject-prefix 'PATCH 5.15.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From d3bc005a62945aec57059201092b12b7c955e5a7 Mon Sep 17 00:00:00 2001
From: Myeonghun Pak <mhun512@gmail.com>
Date: Mon, 14 Sep 2026 20:52:43 -0400
Subject: [PATCH] fbdev: kyro: Release WC setup on registration failure

If register_framebuffer() fails, kyrofb_probe() frees the framebuffer
without releasing its write-combining range. Release the range before
freeing the framebuffer. Earlier failures still skip this cleanup.

The missing cleanup already exists in the initial Git import, before
the conversion from mtrr_add() to arch_phys_wc_add().

This issue was identified during our ongoing static-analysis research
while reviewing kernel code.

Cc: stable@vger.kernel.org
Assisted-by: LLM
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
---
 drivers/video/fbdev/kyro/fbdev.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c
index c237389888229..94d6af54e6c46 100644
--- a/drivers/video/fbdev/kyro/fbdev.c
+++ b/drivers/video/fbdev/kyro/fbdev.c
@@ -765,7 +765,7 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	fb_memset_io(info->screen_base, 0, size);
 
 	if (register_framebuffer(info) < 0)
-		goto out_free_fb;
+		goto out_free_wc;
 
 	fb_info(info, "%s frame buffer device, at %dx%d@%d using %ldk/%ldk of VRAM\n",
 		info->fix.id,
@@ -776,6 +776,8 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	return 0;
 
+out_free_wc:
+	arch_phys_wc_del(currentpar->wc_cookie);
 out_free_fb:
 	framebuffer_release(info);
 
-- 
2.53.0

[PATCH 5.15.y 1/3] fbdev: kyro: Use devm_ioremap() for mmio registers

[Sasha Levin]

From: Giovanni Di Santi <giovanni.disanti.lkl@gmail.com>

[ Upstream commit e0bf12a43243e6afc5a03fc55c58ec48aba48088 ]

Replace the manual ioremap() call for the MMIO registers with the
device-managed devm_ioremap() variant.

This simplifies the driver's resource management by ensuring the memory is
automatically unmapped when the driver detaches from the device.

Signed-off-by: Giovanni Di Santi <giovanni.disanti.lkl@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Stable-dep-of: d3bc005a6294 ("fbdev: kyro: Release WC setup on registration failure")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/kyro/fbdev.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c
index 4979339dbc008..7441d48faea77 100644
--- a/drivers/video/fbdev/kyro/fbdev.c
+++ b/drivers/video/fbdev/kyro/fbdev.c
@@ -713,13 +713,14 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	kyro_fix.mmio_len   = pci_resource_len(pdev, 1);
 
 	currentpar->regbase = deviceInfo.pSTGReg =
-		ioremap(kyro_fix.mmio_start, kyro_fix.mmio_len);
+		devm_ioremap(&pdev->dev, kyro_fix.mmio_start,
+			     kyro_fix.mmio_len);
 	if (!currentpar->regbase)
 		goto out_free_fb;
 
 	info->screen_base = pci_ioremap_wc_bar(pdev, 0);
 	if (!info->screen_base)
-		goto out_unmap_regs;
+		goto out_free_fb;
 
 	if (!nomtrr)
 		currentpar->wc_cookie = arch_phys_wc_add(kyro_fix.smem_start,
@@ -768,8 +769,6 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 out_unmap:
 	iounmap(info->screen_base);
-out_unmap_regs:
-	iounmap(currentpar->regbase);
 out_free_fb:
 	framebuffer_release(info);
 
@@ -792,7 +791,6 @@ static void kyrofb_remove(struct pci_dev *pdev)
 	deviceInfo.ulOverlayOffset = 0;
 
 	iounmap(info->screen_base);
-	iounmap(par->regbase);
 
 	arch_phys_wc_del(par->wc_cookie);
 
-- 
2.53.0

[PATCH 5.15.y 2/3] fbdev: kyro: Use devm_ioremap_wc() for screen mem

[Sasha Levin]

From: Giovanni Di Santi <giovanni.disanti.lkl@gmail.com>

[ Upstream commit 32dfb6112ea3ca143636832cd34234f2be4830bb ]

Replace the manual pci_ioremap_wc() call for mapping screen memory with the
device-managed devm_ioremap_wc() variant.

This simplifies the driver's resource management by ensuring the memory is
automatically unmapped when the driver detaches from the device.

Signed-off-by: Giovanni Di Santi <giovanni.disanti.lkl@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Stable-dep-of: d3bc005a6294 ("fbdev: kyro: Release WC setup on registration failure")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/kyro/fbdev.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c
index 7441d48faea77..b298e9a1b4510 100644
--- a/drivers/video/fbdev/kyro/fbdev.c
+++ b/drivers/video/fbdev/kyro/fbdev.c
@@ -718,7 +718,8 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (!currentpar->regbase)
 		goto out_free_fb;
 
-	info->screen_base = pci_ioremap_wc_bar(pdev, 0);
+	info->screen_base = devm_ioremap_wc(&pdev->dev, kyro_fix.smem_start,
+					    kyro_fix.smem_len);
 	if (!info->screen_base)
 		goto out_free_fb;
 
@@ -756,7 +757,7 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	fb_memset(info->screen_base, 0, size);
 
 	if (register_framebuffer(info) < 0)
-		goto out_unmap;
+		goto out_free_fb;
 
 	fb_info(info, "%s frame buffer device, at %dx%d@%d using %ldk/%ldk of VRAM\n",
 		info->fix.id,
@@ -767,8 +768,6 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	return 0;
 
-out_unmap:
-	iounmap(info->screen_base);
 out_free_fb:
 	framebuffer_release(info);
 
@@ -790,8 +789,6 @@ static void kyrofb_remove(struct pci_dev *pdev)
 	deviceInfo.ulNextFreeVidMem = 0;
 	deviceInfo.ulOverlayOffset = 0;
 
-	iounmap(info->screen_base);
-
 	arch_phys_wc_del(par->wc_cookie);
 
 	unregister_framebuffer(info);
-- 
2.53.0

[PATCH 5.15.y 3/3] fbdev: kyro: Release WC setup on registration failure

[Sasha Levin]

From: Myeonghun Pak <mhun512@gmail.com>

[ Upstream commit d3bc005a62945aec57059201092b12b7c955e5a7 ]

If register_framebuffer() fails, kyrofb_probe() frees the framebuffer
without releasing its write-combining range. Release the range before
freeing the framebuffer. Earlier failures still skip this cleanup.

The missing cleanup already exists in the initial Git import, before
the conversion from mtrr_add() to arch_phys_wc_add().

This issue was identified during our ongoing static-analysis research
while reviewing kernel code.

Cc: stable@vger.kernel.org
Assisted-by: LLM
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/kyro/fbdev.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c
index b298e9a1b4510..c9f8875e34d91 100644
--- a/drivers/video/fbdev/kyro/fbdev.c
+++ b/drivers/video/fbdev/kyro/fbdev.c
@@ -757,7 +757,7 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	fb_memset(info->screen_base, 0, size);
 
 	if (register_framebuffer(info) < 0)
-		goto out_free_fb;
+		goto out_free_wc;
 
 	fb_info(info, "%s frame buffer device, at %dx%d@%d using %ldk/%ldk of VRAM\n",
 		info->fix.id,
@@ -768,6 +768,8 @@ static int kyrofb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	return 0;
 
+out_free_wc:
+	arch_phys_wc_del(currentpar->wc_cookie);
 out_free_fb:
 	framebuffer_release(info);
 
-- 
2.53.0