[PATCH AUTOSEL 4.19 01/10] drm/amd/display: Fix potential null-deref in dm_resume

[PATCH AUTOSEL 4.19 01/10] drm/amd/display: Fix potential null-deref in dm_resume

[Sasha Levin]

From: Roman Li <roman.li@amd.com>

[ Upstream commit 7a7175a2cd84b7874bebbf8e59f134557a34161b ]

[Why]
Fixing smatch error:
dm_resume() error: we previously assumed 'aconnector->dc_link' could be null

[How]
Check if dc_link null at the beginning of the loop,
so further checks can be dropped.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

Reviewed-by: Wayne Lin <Wayne.Lin@amd.com>
Acked-by: Jasdeep Dhillon <jdhillon@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 57678e6dcdc4c..98d51bc204172 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -773,12 +773,14 @@ static int dm_resume(void *handle)
 	list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
 		aconnector = to_amdgpu_dm_connector(connector);
 
+		if (!aconnector->dc_link)
+			continue;
+
 		/*
 		 * this is the case when traversing through already created
 		 * MST connectors, should be skipped
 		 */
-		if (aconnector->dc_link &&
-		    aconnector->dc_link->type == dc_connection_mst_branch)
+		if (aconnector->dc_link->type == dc_connection_mst_branch)
 			continue;
 
 		mutex_lock(&aconnector->hpd_lock);
-- 
2.39.0

[PATCH AUTOSEL 4.19 02/10] drm/radeon: free iio for atombios when driver shutdown

[Sasha Levin]

From: Liwei Song <liwei.song@windriver.com>

[ Upstream commit 4773fadedca918faec443daaca5e4ea1c0ced144 ]

Fix below kmemleak when unload radeon driver:

unreferenced object 0xffff9f8608ede200 (size 512):
  comm "systemd-udevd", pid 326, jiffies 4294682822 (age 716.338s)
  hex dump (first 32 bytes):
    00 00 00 00 c4 aa ec aa 14 ab 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000062fadebe>] kmem_cache_alloc_trace+0x2f1/0x500
    [<00000000b6883cea>] atom_parse+0x117/0x230 [radeon]
    [<00000000158c23fd>] radeon_atombios_init+0xab/0x170 [radeon]
    [<00000000683f672e>] si_init+0x57/0x750 [radeon]
    [<00000000566cc31f>] radeon_device_init+0x559/0x9c0 [radeon]
    [<0000000046efabb3>] radeon_driver_load_kms+0xc1/0x1a0 [radeon]
    [<00000000b5155064>] drm_dev_register+0xdd/0x1d0
    [<0000000045fec835>] radeon_pci_probe+0xbd/0x100 [radeon]
    [<00000000e69ecca3>] pci_device_probe+0xe1/0x160
    [<0000000019484b76>] really_probe.part.0+0xc1/0x2c0
    [<000000003f2649da>] __driver_probe_device+0x96/0x130
    [<00000000231c5bb1>] driver_probe_device+0x24/0xf0
    [<0000000000a42377>] __driver_attach+0x77/0x190
    [<00000000d7574da6>] bus_for_each_dev+0x7f/0xd0
    [<00000000633166d2>] driver_attach+0x1e/0x30
    [<00000000313b05b8>] bus_add_driver+0x12c/0x1e0

iio was allocated in atom_index_iio() called by atom_parse(),
but it doesn't got released when the dirver is shutdown.
Fix this kmemleak by free it in radeon_atombios_fini().

Signed-off-by: Liwei Song <liwei.song@windriver.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/radeon/radeon_device.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index cc1c07963116c..bcca0dd67fd15 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1015,6 +1015,7 @@ void radeon_atombios_fini(struct radeon_device *rdev)
 {
 	if (rdev->mode_info.atom_context) {
 		kfree(rdev->mode_info.atom_context->scratch);
+		kfree(rdev->mode_info.atom_context->iio);
 	}
 	kfree(rdev->mode_info.atom_context);
 	rdev->mode_info.atom_context = NULL;
-- 
2.39.0

[PATCH AUTOSEL 4.19 03/10] drm/msm/dsi: Add missing check for alloc_ordered_workqueue

[Sasha Levin]

From: Jiasheng Jiang <jiasheng@iscas.ac.cn>

[ Upstream commit 115906ca7b535afb1fe7b5406c566ccd3873f82b ]

Add check for the return value of alloc_ordered_workqueue as it may return
NULL pointer and cause NULL pointer dereference.

Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/517646/
Link: https://lore.kernel.org/r/20230110021651.12770-1-jiasheng@iscas.ac.cn
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/msm/dsi/dsi_host.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 56cfa0a03fd5b..059578faa1c6d 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1883,6 +1883,9 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 
 	/* setup workqueue */
 	msm_host->workqueue = alloc_ordered_workqueue("dsi_drm_work", 0);
+	if (!msm_host->workqueue)
+		return -ENOMEM;
+
 	INIT_WORK(&msm_host->err_work, dsi_err_worker);
 	INIT_WORK(&msm_host->hpd_work, dsi_hpd_worker);
 
-- 
2.39.0

[PATCH AUTOSEL 4.19 04/10] docs/scripts/gdb: add necessary make scripts_gdb step

[Sasha Levin]

From: Jakob Koschel <jkl820.git@gmail.com>

[ Upstream commit 6b219431037bf98c9efd49716aea9b68440477a3 ]

In order to debug the kernel successfully with gdb you need to run
'make scripts_gdb' nowadays.

This was changed with the following commit:

Commit 67274c083438340ad16c ("scripts/gdb: delay generation of gdb
constants.py")

In order to have a complete guide for beginners this remark
should be added to the offial documentation.

Signed-off-by: Jakob Koschel <jkl820.git@gmail.com>
Link: https://lore.kernel.org/r/20230112-documentation-gdb-v2-1-292785c43dc9@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 Documentation/dev-tools/gdb-kernel-debugging.rst | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/dev-tools/gdb-kernel-debugging.rst b/Documentation/dev-tools/gdb-kernel-debugging.rst
index 19df79286f000..afe4bc206486c 100644
--- a/Documentation/dev-tools/gdb-kernel-debugging.rst
+++ b/Documentation/dev-tools/gdb-kernel-debugging.rst
@@ -39,6 +39,10 @@ Setup
   this mode. In this case, you should build the kernel with
   CONFIG_RANDOMIZE_BASE disabled if the architecture supports KASLR.
 
+- Build the gdb scripts (required on kernels v5.1 and above)::
+
+    make scripts_gdb
+
 - Enable the gdb stub of QEMU/KVM, either
 
     - at VM startup time by appending "-s" to the QEMU command line
-- 
2.39.0

[PATCH AUTOSEL 4.19 05/10] ASoC: kirkwood: Iterate over array indexes instead of using pointer math

[Sasha Levin]

From: Kees Cook <keescook@chromium.org>

[ Upstream commit b3bcedc0402fcdc5c8624c433562d9d1882749d8 ]

Walking the dram->cs array was seen as accesses beyond the first array
item by the compiler. Instead, use the array index directly. This allows
for run-time bounds checking under CONFIG_UBSAN_BOUNDS as well. Seen
with GCC 13 with -fstrict-flex-arrays:

../sound/soc/kirkwood/kirkwood-dma.c: In function
'kirkwood_dma_conf_mbus_windows.constprop':
../sound/soc/kirkwood/kirkwood-dma.c:90:24: warning: array subscript 0 is outside array bounds of 'const struct mbus_dram_window[0]' [-Warray-bounds=]
   90 |                 if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
      |                      ~~^~~~~~

Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: alsa-devel@alsa-project.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230127224128.never.410-kees@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/soc/kirkwood/kirkwood-dma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/kirkwood/kirkwood-dma.c b/sound/soc/kirkwood/kirkwood-dma.c
index 255cc45905b81..51f75523b691a 100644
--- a/sound/soc/kirkwood/kirkwood-dma.c
+++ b/sound/soc/kirkwood/kirkwood-dma.c
@@ -90,7 +90,7 @@ kirkwood_dma_conf_mbus_windows(void __iomem *base, int win,
 
 	/* try to find matching cs for current dma address */
 	for (i = 0; i < dram->num_cs; i++) {
-		const struct mbus_dram_window *cs = dram->cs + i;
+		const struct mbus_dram_window *cs = &dram->cs[i];
 		if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
 			writel(cs->base & 0xffff0000,
 				base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
-- 
2.39.0

[PATCH AUTOSEL 4.19 06/10] regulator: max77802: Bounds check regulator id against opmode

[Sasha Levin]

From: Kees Cook <keescook@chromium.org>

[ Upstream commit 4fd8bcec5fd7c0d586206fa2f42bd67b06cdaa7e ]

Explicitly bounds-check the id before accessing the opmode array. Seen
with GCC 13:

../drivers/regulator/max77802-regulator.c: In function 'max77802_enable':
../drivers/regulator/max77802-regulator.c:217:29: warning: array subscript [0, 41] is outside array bounds of 'unsigned int[42]' [-Warray-bounds=]
  217 |         if (max77802->opmode[id] == MAX77802_OFF_PWRREQ)
      |             ~~~~~~~~~~~~~~~~^~~~
../drivers/regulator/max77802-regulator.c:62:22: note: while referencing 'opmode'
   62 |         unsigned int opmode[MAX77802_REG_MAX];
      |                      ^~~~~~

Cc: Javier Martinez Canillas <javier@dowhile0.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20230127225203.never.864-kees@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/regulator/max77802-regulator.c | 34 ++++++++++++++++++--------
 1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/regulator/max77802-regulator.c b/drivers/regulator/max77802-regulator.c
index c30cf5c9f2de3..ef314de7c2c01 100644
--- a/drivers/regulator/max77802-regulator.c
+++ b/drivers/regulator/max77802-regulator.c
@@ -97,9 +97,11 @@ static int max77802_set_suspend_disable(struct regulator_dev *rdev)
 {
 	unsigned int val = MAX77802_OFF_PWRREQ;
 	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
-	int id = rdev_get_id(rdev);
+	unsigned int id = rdev_get_id(rdev);
 	int shift = max77802_get_opmode_shift(id);
 
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(max77802->opmode)))
+		return -EINVAL;
 	max77802->opmode[id] = val;
 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  rdev->desc->enable_mask, val << shift);
@@ -113,7 +115,7 @@ static int max77802_set_suspend_disable(struct regulator_dev *rdev)
 static int max77802_set_mode(struct regulator_dev *rdev, unsigned int mode)
 {
 	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
-	int id = rdev_get_id(rdev);
+	unsigned int id = rdev_get_id(rdev);
 	unsigned int val;
 	int shift = max77802_get_opmode_shift(id);
 
@@ -130,6 +132,9 @@ static int max77802_set_mode(struct regulator_dev *rdev, unsigned int mode)
 		return -EINVAL;
 	}
 
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(max77802->opmode)))
+		return -EINVAL;
+
 	max77802->opmode[id] = val;
 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  rdev->desc->enable_mask, val << shift);
@@ -138,8 +143,10 @@ static int max77802_set_mode(struct regulator_dev *rdev, unsigned int mode)
 static unsigned max77802_get_mode(struct regulator_dev *rdev)
 {
 	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
-	int id = rdev_get_id(rdev);
+	unsigned int id = rdev_get_id(rdev);
 
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(max77802->opmode)))
+		return -EINVAL;
 	return max77802_map_mode(max77802->opmode[id]);
 }
 
@@ -163,10 +170,13 @@ static int max77802_set_suspend_mode(struct regulator_dev *rdev,
 				     unsigned int mode)
 {
 	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
-	int id = rdev_get_id(rdev);
+	unsigned int id = rdev_get_id(rdev);
 	unsigned int val;
 	int shift = max77802_get_opmode_shift(id);
 
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(max77802->opmode)))
+		return -EINVAL;
+
 	/*
 	 * If the regulator has been disabled for suspend
 	 * then is invalid to try setting a suspend mode.
@@ -212,9 +222,11 @@ static int max77802_set_suspend_mode(struct regulator_dev *rdev,
 static int max77802_enable(struct regulator_dev *rdev)
 {
 	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
-	int id = rdev_get_id(rdev);
+	unsigned int id = rdev_get_id(rdev);
 	int shift = max77802_get_opmode_shift(id);
 
+	if (WARN_ON_ONCE(id >= ARRAY_SIZE(max77802->opmode)))
+		return -EINVAL;
 	if (max77802->opmode[id] == MAX77802_OFF_PWRREQ)
 		max77802->opmode[id] = MAX77802_OPMODE_NORMAL;
 
@@ -543,7 +555,7 @@ static int max77802_pmic_probe(struct platform_device *pdev)
 
 	for (i = 0; i < MAX77802_REG_MAX; i++) {
 		struct regulator_dev *rdev;
-		int id = regulators[i].id;
+		unsigned int id = regulators[i].id;
 		int shift = max77802_get_opmode_shift(id);
 		int ret;
 
@@ -561,10 +573,12 @@ static int max77802_pmic_probe(struct platform_device *pdev)
 		 * the hardware reports OFF as the regulator operating mode.
 		 * Default to operating mode NORMAL in that case.
 		 */
-		if (val == MAX77802_STATUS_OFF)
-			max77802->opmode[id] = MAX77802_OPMODE_NORMAL;
-		else
-			max77802->opmode[id] = val;
+		if (id < ARRAY_SIZE(max77802->opmode)) {
+			if (val == MAX77802_STATUS_OFF)
+				max77802->opmode[id] = MAX77802_OPMODE_NORMAL;
+			else
+				max77802->opmode[id] = val;
+		}
 
 		rdev = devm_regulator_register(&pdev->dev,
 					       &regulators[i], &config);
-- 
2.39.0

[PATCH AUTOSEL 4.19 07/10] regulator: s5m8767: Bounds check id indexing into arrays

[Sasha Levin]

From: Kees Cook <keescook@chromium.org>

[ Upstream commit e314e15a0b58f9d051c00b25951073bcdae61953 ]

The compiler has no way to know if "id" is within the array bounds of
the regulators array. Add a check for this and a build-time check that
the regulators and reg_voltage_map arrays are sized the same. Seen with
GCC 13:

../drivers/regulator/s5m8767.c: In function 's5m8767_pmic_probe':
../drivers/regulator/s5m8767.c:936:35: warning: array subscript [0, 36] is outside array bounds of 'struct regulator_desc[37]' [-Warray-bounds=]
  936 |                         regulators[id].vsel_reg =
      |                         ~~~~~~~~~~^~~~

Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: linux-samsung-soc@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230128005358.never.313-kees@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/regulator/s5m8767.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/s5m8767.c b/drivers/regulator/s5m8767.c
index 4818df3f8ec91..24c0c82b08a5d 100644
--- a/drivers/regulator/s5m8767.c
+++ b/drivers/regulator/s5m8767.c
@@ -922,10 +922,14 @@ static int s5m8767_pmic_probe(struct platform_device *pdev)
 
 	for (i = 0; i < pdata->num_regulators; i++) {
 		const struct sec_voltage_desc *desc;
-		int id = pdata->regulators[i].id;
+		unsigned int id = pdata->regulators[i].id;
 		int enable_reg, enable_val;
 		struct regulator_dev *rdev;
 
+		BUILD_BUG_ON(ARRAY_SIZE(regulators) != ARRAY_SIZE(reg_voltage_map));
+		if (WARN_ON_ONCE(id >= ARRAY_SIZE(regulators)))
+			continue;
+
 		desc = reg_voltage_map[id];
 		if (desc) {
 			regulators[id].n_voltages =
-- 
2.39.0

[PATCH AUTOSEL 4.19 08/10] pinctrl: at91: use devm_kasprintf() to avoid potential leaks

[Sasha Levin]

From: Claudiu Beznea <claudiu.beznea@microchip.com>

[ Upstream commit 1c4e5c470a56f7f7c649c0c70e603abc1eab15c4 ]

Use devm_kasprintf() instead of kasprintf() to avoid any potential
leaks. At the moment drivers have no remove functionality thus
there is no need for fixes tag.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20230203132714.1931596-1-claudiu.beznea@microchip.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pinctrl/pinctrl-at91-pio4.c | 4 ++--
 drivers/pinctrl/pinctrl-at91.c      | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c
index 9e2f3738bf3ec..89d88e447d44f 100644
--- a/drivers/pinctrl/pinctrl-at91-pio4.c
+++ b/drivers/pinctrl/pinctrl-at91-pio4.c
@@ -1022,8 +1022,8 @@ static int atmel_pinctrl_probe(struct platform_device *pdev)
 
 		pin_desc[i].number = i;
 		/* Pin naming convention: P(bank_name)(bank_pin_number). */
-		pin_desc[i].name = kasprintf(GFP_KERNEL, "P%c%d",
-					     bank + 'A', line);
+		pin_desc[i].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "P%c%d",
+						  bank + 'A', line);
 
 		group->name = group_names[i] = pin_desc[i].name;
 		group->pin = pin_desc[i].number;
diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
index fad0e132ead84..ad01cc5798232 100644
--- a/drivers/pinctrl/pinctrl-at91.c
+++ b/drivers/pinctrl/pinctrl-at91.c
@@ -1782,7 +1782,7 @@ static int at91_gpio_probe(struct platform_device *pdev)
 	}
 
 	for (i = 0; i < chip->ngpio; i++)
-		names[i] = kasprintf(GFP_KERNEL, "pio%c%d", alias_idx + 'A', i);
+		names[i] = devm_kasprintf(&pdev->dev, GFP_KERNEL, "pio%c%d", alias_idx + 'A', i);
 
 	chip->names = (const char *const *)names;
 
-- 
2.39.0

[PATCH AUTOSEL 4.19 09/10] dm thin: add cond_resched() to various workqueue loops

[Sasha Levin]

From: Mike Snitzer <snitzer@kernel.org>

[ Upstream commit e4f80303c2353952e6e980b23914e4214487f2a6 ]

Otherwise on resource constrained systems these workqueues may be too
greedy.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/md/dm-thin.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 386cb33953783..969ea013c74e4 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -2222,6 +2222,7 @@ static void process_thin_deferred_bios(struct thin_c *tc)
 			throttle_work_update(&pool->throttle);
 			dm_pool_issue_prefetches(pool->pmd);
 		}
+		cond_resched();
 	}
 	blk_finish_plug(&plug);
 }
@@ -2305,6 +2306,7 @@ static void process_thin_deferred_cells(struct thin_c *tc)
 			else
 				pool->process_cell(tc, cell);
 		}
+		cond_resched();
 	} while (!list_empty(&cells));
 }
 
-- 
2.39.0

[PATCH AUTOSEL 4.19 10/10] dm cache: add cond_resched() to various workqueue loops

[Sasha Levin]

From: Mike Snitzer <snitzer@kernel.org>

[ Upstream commit 76227f6dc805e9e960128bcc6276647361e0827c ]

Otherwise on resource constrained systems these workqueues may be too
greedy.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/md/dm-cache-target.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index df7bc45bc0ced..b3371812a2158 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -1905,6 +1905,7 @@ static void process_deferred_bios(struct work_struct *ws)
 
 		else
 			commit_needed = process_bio(cache, bio) || commit_needed;
+		cond_resched();
 	}
 
 	if (commit_needed)
@@ -1927,6 +1928,7 @@ static void requeue_deferred_bios(struct cache *cache)
 	while ((bio = bio_list_pop(&bios))) {
 		bio->bi_status = BLK_STS_DM_REQUEUE;
 		bio_endio(bio);
+		cond_resched();
 	}
 }
 
@@ -1967,6 +1969,8 @@ static void check_migrations(struct work_struct *ws)
 		r = mg_start(cache, op, NULL);
 		if (r)
 			break;
+
+		cond_resched();
 	}
 }
 
-- 
2.39.0