The patch titled
Subject: samples/damon/wsse: fix boot time enable handling
has been added to the -mm mm-new branch. Its filename is
samples-damon-wsse-fix-boot-time-enable-handling.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-new branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews. Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: SeongJae Park <sj(a)kernel.org>
Subject: samples/damon/wsse: fix boot time enable handling
Date: Sun, 6 Jul 2025 12:32:02 -0700
Patch series "mm/damon: fix misc bugs in DAMON modules".
From manual code review, I found below bugs in DAMON modules.
DAMON sample modules crash if those are enabled at boot time, via kernel
command line. A similar issue was found and fixed on DAMON non-sample
modules in the past, but we didn't check that for sample modules.
DAMON non-sample modules are not setting 'enabled' parameters accordingly
when real enabling is failed. Honggyu found and fixed[1] this type of
bugs in DAMON sample modules, and my inspection was motivated by the great
work. Kudos to Honggyu.
Finally, DAMON_RECLIAM is mistakenly losing scheme internal status due to
misuse of damon_commit_ctx(). DAMON_LRU_SORT has a similar misuse, but
fortunately it is not causing real status loss.
Fix the bugs. Since these are similar patterns of bugs that were found in
the past, it would be better to add tests or refactor the code, in future.
This patch (of 6):
If 'enable' parameter of the 'wsse' DAMON sample module is set at boot
time via the kernel command line, memory allocation is tried before the
slab is initialized. As a result kernel NULL pointer dereference BUG can
happen. Fix it by checking the initialization status.
Link: https://lkml.kernel.org/r/20250706193207.39810-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20250706193207.39810-2-sj@kernel.org
Link: https://lore.kernel.org/20250702000205.1921-1-honggyu.kim@sk.com [1]
Fixes: b757c6cfc696 ("samples/damon/wsse: start and stop DAMON as the user requests")
Signed-off-by: SeongJae Park <sj(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
samples/damon/wsse.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
--- a/samples/damon/wsse.c~samples-damon-wsse-fix-boot-time-enable-handling
+++ a/samples/damon/wsse.c
@@ -89,6 +89,8 @@ static void damon_sample_wsse_stop(void)
put_pid(target_pidp);
}
+static bool init_called;
+
static int damon_sample_wsse_enable_store(
const char *val, const struct kernel_param *kp)
{
@@ -103,6 +105,9 @@ static int damon_sample_wsse_enable_stor
return 0;
if (enable) {
+ if (!init_called)
+ return 0;
+
err = damon_sample_wsse_start();
if (err)
enable = false;
@@ -114,7 +119,15 @@ static int damon_sample_wsse_enable_stor
static int __init damon_sample_wsse_init(void)
{
- return 0;
+ int err = 0;
+
+ init_called = true;
+ if (enable) {
+ err = damon_sample_wsse_start();
+ if (err)
+ enable = false;
+ }
+ return err;
}
module_init(damon_sample_wsse_init);
_
Patches currently in -mm which might be from sj(a)kernel.org are
mm-damon-core-handle-damon_call_control-as-normal-under-kdmond-deactivation.patch
mm-damon-introduce-damon_stat-module.patch
mm-damon-introduce-damon_stat-module-fix.patch
mm-damon-stat-calculate-and-expose-estimated-memory-bandwidth.patch
mm-damon-stat-calculate-and-expose-idle-time-percentiles.patch
docs-admin-guide-mm-damon-add-damon_stat-usage-document.patch
mm-damon-paddr-use-alloc_migartion_target-with-no-migration-fallback-nodemask.patch
revert-mm-rename-alloc_demote_folio-to-alloc_migrate_folio.patch
revert-mm-make-alloc_demote_folio-externally-invokable-for-migration.patch
selftets-damon-add-a-test-for-memcg_path-leak.patch
mm-damon-sysfs-schemes-decouple-from-damos_quota_goal_metric.patch
mm-damon-sysfs-schemes-decouple-from-damos_action.patch
mm-damon-sysfs-schemes-decouple-from-damos_wmark_metric.patch
mm-damon-sysfs-schemes-decouple-from-damos_filter_type.patch
mm-damon-sysfs-decouple-from-damon_ops_id.patch
selftests-damon-add-drgn-script-for-extracting-damon-status.patch
selftests-damon-_damon_sysfs-set-kdamondpid-in-start.patch
selftests-damon-add-python-and-drgn-based-damon-sysfs-test.patch
selftests-damon-sysfspy-test-monitoring-attribute-parameters.patch
selftests-damon-sysfspy-test-adaptive-targets-parameter.patch
selftests-damon-sysfspy-test-damos-schemes-parameters-setup.patch
mm-damon-add-trace-event-for-auto-tuned-monitoring-intervals.patch
mm-damon-add-trace-event-for-effective-size-quota.patch
samples-damon-wsse-fix-boot-time-enable-handling.patch
samples-damon-prcl-fix-boot-time-enable-crash.patch
samples-damon-mtier-support-boot-time-enable-setup.patch
mm-damon-reclaim-reset-enabled-when-damon-start-failed.patch
mm-damon-lru_sort-reset-enabled-when-damon-start-failed.patch
mm-damon-reclaim-use-parameter-context-correctly.patch
From manual code review, I found below bugs in DAMON modules.
DAMON sample modules crash if those are enabled at boot time, via kernel
command line. A similar issue was found and fixed on DAMON non-sample
modules in the past, but we didn't check that for sample modules.
DAMON non-sample modules are not setting 'enabled' parameters
accordingly when real enabling is failed. Honggyu found and fixed[1]
this type of bugs in DAMON sample modules, and my inspection was
motivated by the great work. Kudos to Honggyu.
Finally, DAMON_RECLIAM is mistakenly losing scheme internal status due
to misuse of damon_commit_ctx(). DAMON_LRU_SORT has a similar misuse,
but fortunately it is not causing real status loss.
Fix the bugs. Since these are similar patterns of bugs that were found
in the past, it would be better to add tests or refactor the code, in
future.
Note that the fix of the second bug for DAMON_STAT is sent
separately[2], since it is a fix for a bug in mm-unstable tree at the
moment. Also as mentioned above, DAMON_LRU_SORT also has a misuse of
damon_commit_ctx(), but it is not causing a real issue, hence the fix is
not included in this series. I will post it later.
[1] https://lore.kernel.org/20250702000205.1921-1-honggyu.kim@sk.com
[2] https://lore.kernel.org/20250706184750.36588-1-sj@kernel.org
SeongJae Park (6):
samples/damon/wsse: fix boot time enable handling
samples/damon/prcl: fix boot time enable crash
samples/damon/mtier: support boot time enable setup
mm/damon/reclaim: reset enabled when DAMON start failed
mm/damon/lru_sort: reset enabled when DAMON start failed
mm/damon/reclaim: use parameter context correctly
mm/damon/lru_sort.c | 5 ++++-
mm/damon/reclaim.c | 9 ++++++---
samples/damon/mtier.c | 13 +++++++++++++
samples/damon/prcl.c | 13 +++++++++++++
samples/damon/wsse.c | 15 ++++++++++++++-
5 files changed, 50 insertions(+), 5 deletions(-)
base-commit: a555ad24c884e9f4ee2f2a0184f5b7b89c8d4a6e
--
2.39.5
Acquire GEM handles in drm_framebuffer_init() and release them in
the corresponding drm_framebuffer_cleanup(). Ties the handle's
lifetime to the framebuffer. Not all GEM buffer objects have GEM
handles. If not set, no refcounting takes place. This is the case
for some fbdev emulation. This is not a problem as these GEM objects
do not use dma-bufs and drivers will not release them while fbdev
emulation is running.
As all drivers use drm_framebuffer_init(), they will now all hold
dma-buf references as fixed in commit 5307dce878d4 ("drm/gem: Acquire
references on GEM handles for framebuffers").
In the GEM framebuffer helpers, restore the original ref counting
on buffer objects. As the helpers for handle refcounting are now
no longer called from outside the DRM core, unexport the symbols.
Gma500 (unnecessarily) clears the framebuffer's GEM-object pointer
before calling drm_framebuffer_cleanup(). Remove these lines to
make it consistent with the rest of the drivers. It's one of the
fbdev emulations with no GEM handle on their buffers. The change
to gma500 is therefore rather cosmetic.
Tested on i915, amdgpu (by Bert) and gma500. Also tested on i915
plus udl for the original problem with dma-buf sharing.
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Fixes: 5307dce878d4 ("drm/gem: Acquire references on GEM handles for framebuffers")
Reported-by: Bert Karwatzki <spasswolf(a)web.de>
Closes: https://lore.kernel.org/dri-devel/20250703115915.3096-1-spasswolf@web.de/
Tested-by: Bert Karwatzki <spasswolf(a)web.de>
Cc: Thomas Zimmermann <tzimmermann(a)suse.de>
Cc: Anusha Srivatsa <asrivats(a)redhat.com>
Cc: Christian König <christian.koenig(a)amd.com>
Cc: Maarten Lankhorst <maarten.lankhorst(a)linux.intel.com>
Cc: Maxime Ripard <mripard(a)kernel.org>
Cc: Sumit Semwal <sumit.semwal(a)linaro.org>
Cc: "Christian König" <christian.koenig(a)amd.com>
Cc: linux-media(a)vger.kernel.org
Cc: dri-devel(a)lists.freedesktop.org
Cc: linaro-mm-sig(a)lists.linaro.org
Cc: <stable(a)vger.kernel.org>
---
drivers/gpu/drm/drm_framebuffer.c | 23 +++++++-
drivers/gpu/drm/drm_gem.c | 59 +++++++++++++-------
drivers/gpu/drm/drm_gem_framebuffer_helper.c | 16 +++---
drivers/gpu/drm/drm_internal.h | 4 +-
drivers/gpu/drm/gma500/fbdev.c | 2 -
5 files changed, 69 insertions(+), 35 deletions(-)
diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index b781601946db..e4a10dd053fc 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -862,11 +862,17 @@ EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_framebuffer_free);
int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
const struct drm_framebuffer_funcs *funcs)
{
+ unsigned int i;
int ret;
if (WARN_ON_ONCE(fb->dev != dev || !fb->format))
return -EINVAL;
+ for (i = 0; i < fb->format->num_planes; i++) {
+ if (fb->obj[i])
+ drm_gem_object_handle_get_if_exists_unlocked(fb->obj[i]);
+ }
+
INIT_LIST_HEAD(&fb->filp_head);
fb->funcs = funcs;
@@ -875,7 +881,7 @@ int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
ret = __drm_mode_object_add(dev, &fb->base, DRM_MODE_OBJECT_FB,
false, drm_framebuffer_free);
if (ret)
- goto out;
+ goto err;
mutex_lock(&dev->mode_config.fb_lock);
dev->mode_config.num_fb++;
@@ -883,7 +889,14 @@ int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
mutex_unlock(&dev->mode_config.fb_lock);
drm_mode_object_register(dev, &fb->base);
-out:
+
+ return 0;
+
+err:
+ for (i = 0; i < fb->format->num_planes; i++) {
+ if (fb->obj[i])
+ drm_gem_object_handle_put_if_exists_unlocked(fb->obj[i]);
+ }
return ret;
}
EXPORT_SYMBOL(drm_framebuffer_init);
@@ -960,6 +973,12 @@ EXPORT_SYMBOL(drm_framebuffer_unregister_private);
void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
{
struct drm_device *dev = fb->dev;
+ unsigned int i;
+
+ for (i = 0; i < fb->format->num_planes; i++) {
+ if (fb->obj[i])
+ drm_gem_object_handle_put_if_exists_unlocked(fb->obj[i]);
+ }
mutex_lock(&dev->mode_config.fb_lock);
list_del(&fb->head);
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index bc505d938b3e..9d8b9e6b7d25 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -224,23 +224,27 @@ static void drm_gem_object_handle_get(struct drm_gem_object *obj)
}
/**
- * drm_gem_object_handle_get_unlocked - acquire reference on user-space handles
+ * drm_gem_object_handle_get_if_exists_unlocked - acquire reference on user-space handle, if any
* @obj: GEM object
*
- * Acquires a reference on the GEM buffer object's handle. Required
- * to keep the GEM object alive. Call drm_gem_object_handle_put_unlocked()
- * to release the reference.
+ * Acquires a reference on the GEM buffer object's handle. Required to keep
+ * the GEM object alive. Call drm_gem_object_handle_put_if_exists_unlocked()
+ * to release the reference. Does nothing if the buffer object has no handle.
*/
-void drm_gem_object_handle_get_unlocked(struct drm_gem_object *obj)
+void drm_gem_object_handle_get_if_exists_unlocked(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
guard(mutex)(&dev->object_name_lock);
- drm_WARN_ON(dev, !obj->handle_count); /* first ref taken in create-tail helper */
- drm_gem_object_handle_get(obj);
+ /*
+ * First ref taken during GEM object creation, if any. Some
+ * drivers set up internal framebuffers with GEM objects that
+ * do not have a GEM handle. Hence, this counter can be zero.
+ */
+ if (obj->handle_count)
+ drm_gem_object_handle_get(obj);
}
-EXPORT_SYMBOL(drm_gem_object_handle_get_unlocked);
/**
* drm_gem_object_handle_free - release resources bound to userspace handles
@@ -272,21 +276,11 @@ static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj)
}
}
-/**
- * drm_gem_object_handle_put_unlocked - releases reference on user-space handles
- * @obj: GEM object
- *
- * Releases a reference on the GEM buffer object's handle. Possibly releases
- * the GEM buffer object and associated dma-buf objects.
- */
-void drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj)
+static void drm_gem_object_handle_put_unlocked_tail(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
bool final = false;
- if (WARN_ON(READ_ONCE(obj->handle_count) == 0))
- return;
-
/*
* Must bump handle count first as this may be the last
* ref, in which case the object would disappear before we
@@ -304,7 +298,32 @@ void drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj)
if (final)
drm_gem_object_put(obj);
}
-EXPORT_SYMBOL(drm_gem_object_handle_put_unlocked);
+
+static void drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj)
+{
+ struct drm_device *dev = obj->dev;
+
+ if (drm_WARN_ON(dev, READ_ONCE(obj->handle_count) == 0))
+ return;
+
+ drm_gem_object_handle_put_unlocked_tail(obj);
+}
+
+/**
+ * drm_gem_object_handle_put_if_exists_unlocked - releases reference on user-space handle, if any
+ * @obj: GEM object
+ *
+ * Releases a reference on the GEM buffer object's handle. Possibly releases
+ * the GEM buffer object and associated dma-buf objects. Does nothing if the
+ * buffer object has no handle.
+ */
+void drm_gem_object_handle_put_if_exists_unlocked(struct drm_gem_object *obj)
+{
+ if (!obj->handle_count)
+ return;
+
+ drm_gem_object_handle_put_unlocked_tail(obj);
+}
/*
* Called at device or object close to release the file's
diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index c60d0044d036..618ce725cd75 100644
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -100,7 +100,7 @@ void drm_gem_fb_destroy(struct drm_framebuffer *fb)
unsigned int i;
for (i = 0; i < fb->format->num_planes; i++)
- drm_gem_object_handle_put_unlocked(fb->obj[i]);
+ drm_gem_object_put(fb->obj[i]);
drm_framebuffer_cleanup(fb);
kfree(fb);
@@ -183,10 +183,8 @@ int drm_gem_fb_init_with_funcs(struct drm_device *dev,
if (!objs[i]) {
drm_dbg_kms(dev, "Failed to lookup GEM object\n");
ret = -ENOENT;
- goto err_gem_object_handle_put_unlocked;
+ goto err_gem_object_put;
}
- drm_gem_object_handle_get_unlocked(objs[i]);
- drm_gem_object_put(objs[i]);
min_size = (height - 1) * mode_cmd->pitches[i]
+ drm_format_info_min_pitch(info, i, width)
@@ -196,22 +194,22 @@ int drm_gem_fb_init_with_funcs(struct drm_device *dev,
drm_dbg_kms(dev,
"GEM object size (%zu) smaller than minimum size (%u) for plane %d\n",
objs[i]->size, min_size, i);
- drm_gem_object_handle_put_unlocked(objs[i]);
+ drm_gem_object_put(objs[i]);
ret = -EINVAL;
- goto err_gem_object_handle_put_unlocked;
+ goto err_gem_object_put;
}
}
ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs);
if (ret)
- goto err_gem_object_handle_put_unlocked;
+ goto err_gem_object_put;
return 0;
-err_gem_object_handle_put_unlocked:
+err_gem_object_put:
while (i > 0) {
--i;
- drm_gem_object_handle_put_unlocked(objs[i]);
+ drm_gem_object_put(objs[i]);
}
return ret;
}
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index f7b414a813ae..9233019f54a8 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -161,8 +161,8 @@ void drm_sysfs_lease_event(struct drm_device *dev);
/* drm_gem.c */
int drm_gem_init(struct drm_device *dev);
-void drm_gem_object_handle_get_unlocked(struct drm_gem_object *obj);
-void drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj);
+void drm_gem_object_handle_get_if_exists_unlocked(struct drm_gem_object *obj);
+void drm_gem_object_handle_put_if_exists_unlocked(struct drm_gem_object *obj);
int drm_gem_handle_create_tail(struct drm_file *file_priv,
struct drm_gem_object *obj,
u32 *handlep);
diff --git a/drivers/gpu/drm/gma500/fbdev.c b/drivers/gpu/drm/gma500/fbdev.c
index 8edefea2ef59..afd252108cfa 100644
--- a/drivers/gpu/drm/gma500/fbdev.c
+++ b/drivers/gpu/drm/gma500/fbdev.c
@@ -121,7 +121,6 @@ static void psb_fbdev_fb_destroy(struct fb_info *info)
drm_fb_helper_fini(fb_helper);
drm_framebuffer_unregister_private(fb);
- fb->obj[0] = NULL;
drm_framebuffer_cleanup(fb);
kfree(fb);
@@ -243,7 +242,6 @@ int psb_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
err_drm_framebuffer_unregister_private:
drm_framebuffer_unregister_private(fb);
- fb->obj[0] = NULL;
drm_framebuffer_cleanup(fb);
kfree(fb);
err_drm_gem_object_put:
--
2.50.0
The patch below does not apply to the 5.4-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-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x ec54c0a20709ed6e56f40a8d59eee725c31a916b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070655-graded-numbly-6d00@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From ec54c0a20709ed6e56f40a8d59eee725c31a916b Mon Sep 17 00:00:00 2001
From: Sergey Senozhatsky <senozhatsky(a)chromium.org>
Date: Wed, 25 Jun 2025 14:20:37 +0900
Subject: [PATCH] mtk-sd: reset host->mrq on prepare_data() error
Do not leave host with dangling ->mrq pointer if we hit
the msdc_prepare_data() error out path.
Signed-off-by: Sergey Senozhatsky <senozhatsky(a)chromium.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat(a)kernel.org>
Fixes: f5de469990f1 ("mtk-sd: Prevent memory corruption from DMA map failure")
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20250625052106.584905-1-senozhatsky@chromium.org
Signed-off-by: Ulf Hansson <ulf.hansson(a)linaro.org>
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index b12cfb9a5e5f..d7020e06dd55 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -1492,6 +1492,7 @@ static void msdc_ops_request(struct mmc_host *mmc, struct mmc_request *mrq)
if (mrq->data) {
msdc_prepare_data(host, mrq->data);
if (!msdc_data_prepared(mrq->data)) {
+ host->mrq = NULL;
/*
* Failed to prepare DMA area, fail fast before
* starting any commands.
The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x ec54c0a20709ed6e56f40a8d59eee725c31a916b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070655-kindred-magnify-4bcf@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From ec54c0a20709ed6e56f40a8d59eee725c31a916b Mon Sep 17 00:00:00 2001
From: Sergey Senozhatsky <senozhatsky(a)chromium.org>
Date: Wed, 25 Jun 2025 14:20:37 +0900
Subject: [PATCH] mtk-sd: reset host->mrq on prepare_data() error
Do not leave host with dangling ->mrq pointer if we hit
the msdc_prepare_data() error out path.
Signed-off-by: Sergey Senozhatsky <senozhatsky(a)chromium.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat(a)kernel.org>
Fixes: f5de469990f1 ("mtk-sd: Prevent memory corruption from DMA map failure")
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20250625052106.584905-1-senozhatsky@chromium.org
Signed-off-by: Ulf Hansson <ulf.hansson(a)linaro.org>
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index b12cfb9a5e5f..d7020e06dd55 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -1492,6 +1492,7 @@ static void msdc_ops_request(struct mmc_host *mmc, struct mmc_request *mrq)
if (mrq->data) {
msdc_prepare_data(host, mrq->data);
if (!msdc_data_prepared(mrq->data)) {
+ host->mrq = NULL;
/*
* Failed to prepare DMA area, fail fast before
* starting any commands.