[PATCH AUTOSEL 5.15 1/4] locking/semaphore: Use wake_q to wake up processes outside lock critical section

[PATCH AUTOSEL 5.15 1/4] locking/semaphore: Use wake_q to wake up processes outside lock critical section

[Sasha Levin]

From: Waiman Long <longman@redhat.com>

[ Upstream commit 85b2b9c16d053364e2004883140538e73b333cdb ]

A circular lock dependency splat has been seen involving down_trylock():

  ======================================================
  WARNING: possible circular locking dependency detected
  6.12.0-41.el10.s390x+debug
  ------------------------------------------------------
  dd/32479 is trying to acquire lock:
  0015a20accd0d4f8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x26/0x90

  but task is already holding lock:
  000000017e461698 (&zone->lock){-.-.}-{2:2}, at: rmqueue_bulk+0xac/0x8f0

  the existing dependency chain (in reverse order) is:
  -> #4 (&zone->lock){-.-.}-{2:2}:
  -> #3 (hrtimer_bases.lock){-.-.}-{2:2}:
  -> #2 (&rq->__lock){-.-.}-{2:2}:
  -> #1 (&p->pi_lock){-.-.}-{2:2}:
  -> #0 ((console_sem).lock){-.-.}-{2:2}:

The console_sem -> pi_lock dependency is due to calling try_to_wake_up()
while holding the console_sem raw_spinlock. This dependency can be broken
by using wake_q to do the wakeup instead of calling try_to_wake_up()
under the console_sem lock. This will also make the semaphore's
raw_spinlock become a terminal lock without taking any further locks
underneath it.

The hrtimer_bases.lock is a raw_spinlock while zone->lock is a
spinlock. The hrtimer_bases.lock -> zone->lock dependency happens via
the debug_objects_fill_pool() helper function in the debugobjects code.

  -> #4 (&zone->lock){-.-.}-{2:2}:
         __lock_acquire+0xe86/0x1cc0
         lock_acquire.part.0+0x258/0x630
         lock_acquire+0xb8/0xe0
         _raw_spin_lock_irqsave+0xb4/0x120
         rmqueue_bulk+0xac/0x8f0
         __rmqueue_pcplist+0x580/0x830
         rmqueue_pcplist+0xfc/0x470
         rmqueue.isra.0+0xdec/0x11b0
         get_page_from_freelist+0x2ee/0xeb0
         __alloc_pages_noprof+0x2c2/0x520
         alloc_pages_mpol_noprof+0x1fc/0x4d0
         alloc_pages_noprof+0x8c/0xe0
         allocate_slab+0x320/0x460
         ___slab_alloc+0xa58/0x12b0
         __slab_alloc.isra.0+0x42/0x60
         kmem_cache_alloc_noprof+0x304/0x350
         fill_pool+0xf6/0x450
         debug_object_activate+0xfe/0x360
         enqueue_hrtimer+0x34/0x190
         __run_hrtimer+0x3c8/0x4c0
         __hrtimer_run_queues+0x1b2/0x260
         hrtimer_interrupt+0x316/0x760
         do_IRQ+0x9a/0xe0
         do_irq_async+0xf6/0x160

Normally a raw_spinlock to spinlock dependency is not legitimate
and will be warned if CONFIG_PROVE_RAW_LOCK_NESTING is enabled,
but debug_objects_fill_pool() is an exception as it explicitly
allows this dependency for non-PREEMPT_RT kernel without causing
PROVE_RAW_LOCK_NESTING lockdep splat. As a result, this dependency is
legitimate and not a bug.

Anyway, semaphore is the only locking primitive left that is still
using try_to_wake_up() to do wakeup inside critical section, all the
other locking primitives had been migrated to use wake_q to do wakeup
outside of the critical section. It is also possible that there are
other circular locking dependencies involving printk/console_sem or
other existing/new semaphores lurking somewhere which may show up in
the future. Let just do the migration now to wake_q to avoid headache
like this.

Reported-by: yzbot+ed801a886dfdbfe7136d@syzkaller.appspotmail.com
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250307232717.1759087-3-boqun.feng@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/locking/semaphore.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c
index 9ee381e4d2a4d..a26c915430ba0 100644
--- a/kernel/locking/semaphore.c
+++ b/kernel/locking/semaphore.c
@@ -29,6 +29,7 @@
 #include <linux/export.h>
 #include <linux/sched.h>
 #include <linux/sched/debug.h>
+#include <linux/sched/wake_q.h>
 #include <linux/semaphore.h>
 #include <linux/spinlock.h>
 #include <linux/ftrace.h>
@@ -37,7 +38,7 @@ static noinline void __down(struct semaphore *sem);
 static noinline int __down_interruptible(struct semaphore *sem);
 static noinline int __down_killable(struct semaphore *sem);
 static noinline int __down_timeout(struct semaphore *sem, long timeout);
-static noinline void __up(struct semaphore *sem);
+static noinline void __up(struct semaphore *sem, struct wake_q_head *wake_q);
 
 /**
  * down - acquire the semaphore
@@ -182,13 +183,16 @@ EXPORT_SYMBOL(down_timeout);
 void up(struct semaphore *sem)
 {
 	unsigned long flags;
+	DEFINE_WAKE_Q(wake_q);
 
 	raw_spin_lock_irqsave(&sem->lock, flags);
 	if (likely(list_empty(&sem->wait_list)))
 		sem->count++;
 	else
-		__up(sem);
+		__up(sem, &wake_q);
 	raw_spin_unlock_irqrestore(&sem->lock, flags);
+	if (!wake_q_empty(&wake_q))
+		wake_up_q(&wake_q);
 }
 EXPORT_SYMBOL(up);
 
@@ -256,11 +260,12 @@ static noinline int __sched __down_timeout(struct semaphore *sem, long timeout)
 	return __down_common(sem, TASK_UNINTERRUPTIBLE, timeout);
 }
 
-static noinline void __sched __up(struct semaphore *sem)
+static noinline void __sched __up(struct semaphore *sem,
+				  struct wake_q_head *wake_q)
 {
 	struct semaphore_waiter *waiter = list_first_entry(&sem->wait_list,
 						struct semaphore_waiter, list);
 	list_del(&waiter->list);
 	waiter->up = true;
-	wake_up_process(waiter->task);
+	wake_q_add(wake_q, waiter->task);
 }
-- 
2.39.5

[PATCH AUTOSEL 5.15 2/4] x86/sgx: Warn explicitly if X86_FEATURE_SGX_LC is not enabled

[Sasha Levin]

From: Vladis Dronov <vdronov@redhat.com>

[ Upstream commit 65be5c95d08eedda570a6c888a12384c77fe7614 ]

The kernel requires X86_FEATURE_SGX_LC to be able to create SGX enclaves,
not just X86_FEATURE_SGX.

There is quite a number of hardware which has X86_FEATURE_SGX but not
X86_FEATURE_SGX_LC. A kernel running on such hardware does not create
the /dev/sgx_enclave file and does so silently.

Explicitly warn if X86_FEATURE_SGX_LC is not enabled to properly notify
users that the kernel disabled the SGX driver.

The X86_FEATURE_SGX_LC, a.k.a. SGX Launch Control, is a CPU feature
that enables LE (Launch Enclave) hash MSRs to be writable (with
additional opt-in required in the 'feature control' MSR) when running
enclaves, i.e. using a custom root key rather than the Intel proprietary
key for enclave signing.

I've hit this issue myself and have spent some time researching where
my /dev/sgx_enclave file went on SGX-enabled hardware.

Related links:

  https://github.com/intel/linux-sgx/issues/837
  https://patchwork.kernel.org/project/platform-driver-x86/patch/20180827185507.17087-3-jarkko.sakkinen@linux.intel.com/

[ mingo: Made the error message a bit more verbose, and added other cases
         where the kernel fails to create the /dev/sgx_enclave device node. ]

Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Kai Huang <kai.huang@intel.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250309172215.21777-2-vdronov@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/x86/kernel/cpu/sgx/driver.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/driver.c b/arch/x86/kernel/cpu/sgx/driver.c
index aa9b8b8688676..afccb69cd9a2c 100644
--- a/arch/x86/kernel/cpu/sgx/driver.c
+++ b/arch/x86/kernel/cpu/sgx/driver.c
@@ -150,13 +150,15 @@ int __init sgx_drv_init(void)
 	u64 xfrm_mask;
 	int ret;
 
-	if (!cpu_feature_enabled(X86_FEATURE_SGX_LC))
+	if (!cpu_feature_enabled(X86_FEATURE_SGX_LC)) {
+		pr_info("SGX disabled: SGX launch control CPU feature is not available, /dev/sgx_enclave disabled.\n");
 		return -ENODEV;
+	}
 
 	cpuid_count(SGX_CPUID, 0, &eax, &ebx, &ecx, &edx);
 
 	if (!(eax & 1))  {
-		pr_err("SGX disabled: SGX1 instruction support not available.\n");
+		pr_info("SGX disabled: SGX1 instruction support not available, /dev/sgx_enclave disabled.\n");
 		return -ENODEV;
 	}
 
@@ -173,8 +175,10 @@ int __init sgx_drv_init(void)
 	}
 
 	ret = misc_register(&sgx_dev_enclave);
-	if (ret)
+	if (ret) {
+		pr_info("SGX disabled: Unable to register the /dev/sgx_enclave driver (%d).\n", ret);
 		return ret;
+	}
 
 	return 0;
 }
-- 
2.39.5

[PATCH AUTOSEL 5.15 3/4] drm/amd: Keep display off while going into S4

[Sasha Levin]

From: Mario Limonciello <mario.limonciello@amd.com>

[ Upstream commit 4afacc9948e1f8fdbca401d259ae65ad93d298c0 ]

When userspace invokes S4 the flow is:

1) amdgpu_pmops_prepare()
2) amdgpu_pmops_freeze()
3) Create hibernation image
4) amdgpu_pmops_thaw()
5) Write out image to disk
6) Turn off system

Then on resume amdgpu_pmops_restore() is called.

This flow has a problem that because amdgpu_pmops_thaw() is called
it will call amdgpu_device_resume() which will resume all of the GPU.

This includes turning the display hardware back on and discovering
connectors again.

This is an unexpected experience for the display to turn back on.
Adjust the flow so that during the S4 sequence display hardware is
not turned back on.

Reported-by: Xaver Hugl <xaver.hugl@gmail.com>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/2038
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Link: https://lore.kernel.org/r/20250306185124.44780-1-mario.limonciello@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 68bfdc8dc0a1a7fdd9ab61e69907ae71a6fd3d91)
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c           | 11 +++++++++--
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  5 +++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 57943e9008710..adcf3adc5ca51 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -2294,7 +2294,6 @@ static int amdgpu_pmops_freeze(struct device *dev)
 
 	adev->in_s4 = true;
 	r = amdgpu_device_suspend(drm_dev, true);
-	adev->in_s4 = false;
 	if (r)
 		return r;
 	return amdgpu_asic_reset(adev);
@@ -2303,8 +2302,13 @@ static int amdgpu_pmops_freeze(struct device *dev)
 static int amdgpu_pmops_thaw(struct device *dev)
 {
 	struct drm_device *drm_dev = dev_get_drvdata(dev);
+	struct amdgpu_device *adev = drm_to_adev(drm_dev);
+	int r;
 
-	return amdgpu_device_resume(drm_dev, true);
+	r = amdgpu_device_resume(drm_dev, true);
+	adev->in_s4 = false;
+
+	return r;
 }
 
 static int amdgpu_pmops_poweroff(struct device *dev)
@@ -2317,6 +2321,9 @@ static int amdgpu_pmops_poweroff(struct device *dev)
 static int amdgpu_pmops_restore(struct device *dev)
 {
 	struct drm_device *drm_dev = dev_get_drvdata(dev);
+	struct amdgpu_device *adev = drm_to_adev(drm_dev);
+
+	adev->in_s4 = false;
 
 	return amdgpu_device_resume(drm_dev, true);
 }
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 bfa15d8959553..c93b27b6b17a6 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2700,6 +2700,11 @@ static int dm_resume(void *handle)
 
 		return 0;
 	}
+
+	/* leave display off for S4 sequence */
+	if (adev->in_s4)
+		return 0;
+
 	/* Recreate dc_state - DC invalidates it when setting power state to S3. */
 	dc_release_state(dm_state->context);
 	dm_state->context = dc_create_state(dm->dc);
-- 
2.39.5

[PATCH AUTOSEL 5.15 4/4] ALSA: hda/realtek: Add mute LED quirk for HP Pavilion x360 14-dy1xxx

[Sasha Levin]

From: Navon John Lukose <navonjohnlukose@gmail.com>

[ Upstream commit b11a74ac4f545626d0dc95a8ca8c41df90532bf3 ]

Add a fixup to enable the mute LED on HP Pavilion x360 Convertible
14-dy1xxx with ALC295 codec. The appropriate coefficient index and bits
were identified through a brute-force method, as detailed in
https://bbs.archlinux.org/viewtopic.php?pid=2079504#p2079504.

Signed-off-by: Navon John Lukose <navonjohnlukose@gmail.com>
Link: https://patch.msgid.link/20250307213319.35507-1-navonjohnlukose@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/pci/hda/patch_realtek.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 6440a79f4d480..f60e10a0c657f 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -4757,6 +4757,21 @@ static void alc236_fixup_hp_coef_micmute_led(struct hda_codec *codec,
 	}
 }
 
+static void alc295_fixup_hp_mute_led_coefbit11(struct hda_codec *codec,
+				const struct hda_fixup *fix, int action)
+{
+	struct alc_spec *spec = codec->spec;
+
+	if (action == HDA_FIXUP_ACT_PRE_PROBE) {
+		spec->mute_led_polarity = 0;
+		spec->mute_led_coef.idx = 0xb;
+		spec->mute_led_coef.mask = 3 << 3;
+		spec->mute_led_coef.on = 1 << 3;
+		spec->mute_led_coef.off = 1 << 4;
+		snd_hda_gen_add_mute_led_cdev(codec, coef_mute_led_set);
+	}
+}
+
 static void alc285_fixup_hp_mute_led(struct hda_codec *codec,
 				const struct hda_fixup *fix, int action)
 {
@@ -6996,6 +7011,7 @@ enum {
 	ALC290_FIXUP_MONO_SPEAKERS_HSJACK,
 	ALC290_FIXUP_SUBWOOFER,
 	ALC290_FIXUP_SUBWOOFER_HSJACK,
+	ALC295_FIXUP_HP_MUTE_LED_COEFBIT11,
 	ALC269_FIXUP_THINKPAD_ACPI,
 	ALC269_FIXUP_DMIC_THINKPAD_ACPI,
 	ALC269VB_FIXUP_INFINIX_ZERO_BOOK_13,
@@ -8542,6 +8558,10 @@ static const struct hda_fixup alc269_fixups[] = {
 		.chained = true,
 		.chain_id = ALC283_FIXUP_INT_MIC,
 	},
+	[ALC295_FIXUP_HP_MUTE_LED_COEFBIT11] = {
+		.type = HDA_FIXUP_FUNC,
+		.v.func = alc295_fixup_hp_mute_led_coefbit11,
+	},
 	[ALC298_FIXUP_SAMSUNG_AMP] = {
 		.type = HDA_FIXUP_FUNC,
 		.v.func = alc298_fixup_samsung_amp,
@@ -9256,6 +9276,7 @@ static const struct snd_pci_quirk alc269_fixup_tbl[] = {
 	SND_PCI_QUIRK(0x103c, 0x84e7, "HP Pavilion 15", ALC269_FIXUP_HP_MUTE_LED_MIC3),
 	SND_PCI_QUIRK(0x103c, 0x8519, "HP Spectre x360 15-df0xxx", ALC285_FIXUP_HP_SPECTRE_X360),
 	SND_PCI_QUIRK(0x103c, 0x8537, "HP ProBook 440 G6", ALC236_FIXUP_HP_MUTE_LED_MICMUTE_VREF),
+	SND_PCI_QUIRK(0x103c, 0x85c6, "HP Pavilion x360 Convertible 14-dy1xxx", ALC295_FIXUP_HP_MUTE_LED_COEFBIT11),
 	SND_PCI_QUIRK(0x103c, 0x85de, "HP Envy x360 13-ar0xxx", ALC285_FIXUP_HP_ENVY_X360),
 	SND_PCI_QUIRK(0x103c, 0x860f, "HP ZBook 15 G6", ALC285_FIXUP_HP_GPIO_AMP_INIT),
 	SND_PCI_QUIRK(0x103c, 0x861f, "HP Elite Dragonfly G1", ALC285_FIXUP_HP_GPIO_AMP_INIT),
-- 
2.39.5