We flush the rebind worker during the vm close phase, however in places
like preempt_fence_work_func() we seem to queue the rebind worker
without first checking if the vm has already been closed. The concern
here is the vm being closed with the worker flushed, but then being
rearmed later, which looks like potential uaf, since there is no actual
refcounting to track the queued worker. We can't take the vm->lock here
in preempt_rebind_work_func() to first check if the vm is closed since
that will deadlock, so instead flush the worker again when the vm
refcount reaches zero.
v2:
- Grabbing vm->lock in the preempt worker creates a deadlock, so
checking the closed state is tricky. Instead flush the worker when
the refcount reaches zero. It should be impossible to queue the
preempt worker without already holding vm ref.
Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1676
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1591
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1304
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1249
Signed-off-by: Matthew Auld <matthew.auld(a)intel.com>
Cc: Matthew Brost <matthew.brost(a)intel.com>
Cc: <stable(a)vger.kernel.org> # v6.8+
---
drivers/gpu/drm/xe/xe_vm.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 2ba7c920a8af..71de9848bdc2 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -1509,6 +1509,9 @@ static void vm_destroy_work_func(struct work_struct *w)
/* xe_vm_close_and_put was not called? */
xe_assert(xe, !vm->size);
+ if (xe_vm_in_preempt_fence_mode(vm))
+ flush_work(&vm->preempt.rebind_work);
+
mutex_destroy(&vm->snap_mutex);
if (!(vm->flags & XE_VM_FLAG_MIGRATION))
--
2.44.0
From: Eric Biggers <ebiggers(a)google.com>
Since the signature self-test uses RSA and SHA-256, it must only be
enabled when those algorithms are enabled. Otherwise it fails and
panics the kernel on boot-up.
Reported-by: kernel test robot <oliver.sang(a)intel.com>
Closes: https://lore.kernel.org/oe-lkp/202404221528.51d75177-lkp@intel.com
Fixes: 3cde3174eb91 ("certs: Add FIPS selftests")
Cc: stable(a)vger.kernel.org
Cc: Simo Sorce <simo(a)redhat.com>
Cc: David Howells <dhowells(a)redhat.com>
Signed-off-by: Eric Biggers <ebiggers(a)google.com>
---
crypto/asymmetric_keys/Kconfig | 2 ++
1 file changed, 2 insertions(+)
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
index 59ec726b7c77..4abc58c55efa 100644
--- a/crypto/asymmetric_keys/Kconfig
+++ b/crypto/asymmetric_keys/Kconfig
@@ -83,7 +83,9 @@ config FIPS_SIGNATURE_SELFTEST
for FIPS.
depends on KEYS
depends on ASYMMETRIC_KEY_TYPE
depends on PKCS7_MESSAGE_PARSER=X509_CERTIFICATE_PARSER
depends on X509_CERTIFICATE_PARSER
+ depends on CRYPTO_RSA
+ depends on CRYPTO_SHA256
endif # ASYMMETRIC_KEY_TYPE
base-commit: ed30a4a51bb196781c8058073ea720133a65596f
--
2.44.0
From: Eric Biggers <ebiggers(a)google.com>
Make ASYMMETRIC_PUBLIC_KEY_SUBTYPE select CRYPTO_SIG to avoid build
errors like the following, which were possible with
CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE=y && CONFIG_CRYPTO_SIG=n:
ld: vmlinux.o: in function `public_key_verify_signature':
(.text+0x306280): undefined reference to `crypto_alloc_sig'
ld: (.text+0x306300): undefined reference to `crypto_sig_set_pubkey'
ld: (.text+0x306324): undefined reference to `crypto_sig_verify'
ld: (.text+0x30636c): undefined reference to `crypto_sig_set_privkey'
Fixes: 63ba4d67594a ("KEYS: asymmetric: Use new crypto interface without scatterlists")
Cc: stable(a)vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers(a)google.com>
---
crypto/asymmetric_keys/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
index 59ec726b7c77..3f089abd6fc9 100644
--- a/crypto/asymmetric_keys/Kconfig
+++ b/crypto/asymmetric_keys/Kconfig
@@ -13,10 +13,11 @@ if ASYMMETRIC_KEY_TYPE
config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
tristate "Asymmetric public-key crypto algorithm subtype"
select MPILIB
select CRYPTO_HASH_INFO
select CRYPTO_AKCIPHER
+ select CRYPTO_SIG
select CRYPTO_HASH
help
This option provides support for asymmetric public key type handling.
If signature generation and/or verification are to be used,
appropriate hash algorithms (such as SHA-1) must be available.
base-commit: ed30a4a51bb196781c8058073ea720133a65596f
--
2.44.0
The patch below does not apply to the 6.1-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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 1e560864159d002b453da42bd2c13a1805515a20
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024021334-each-residence-41ce@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
1e560864159d ("PCI/ASPM: Fix deadlock when enabling ASPM")
ac865f00af29 ("Merge tag 'pci-v6.7-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1e560864159d002b453da42bd2c13a1805515a20 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan+linaro(a)kernel.org>
Date: Tue, 30 Jan 2024 11:02:43 +0100
Subject: [PATCH] PCI/ASPM: Fix deadlock when enabling ASPM
A last minute revert in 6.7-final introduced a potential deadlock when
enabling ASPM during probe of Qualcomm PCIe controllers as reported by
lockdep:
============================================
WARNING: possible recursive locking detected
6.7.0 #40 Not tainted
--------------------------------------------
kworker/u16:5/90 is trying to acquire lock:
ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc
but task is already holding lock:
ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(pci_bus_sem);
lock(pci_bus_sem);
*** DEADLOCK ***
Call trace:
print_deadlock_bug+0x25c/0x348
__lock_acquire+0x10a4/0x2064
lock_acquire+0x1e8/0x318
down_read+0x60/0x184
pcie_aspm_pm_state_change+0x58/0xdc
pci_set_full_power_state+0xa8/0x114
pci_set_power_state+0xc4/0x120
qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom]
pci_walk_bus+0x64/0xbc
qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom]
The deadlock can easily be reproduced on machines like the Lenovo ThinkPad
X13s by adding a delay to increase the race window during asynchronous
probe where another thread can take a write lock.
Add a new pci_set_power_state_locked() and associated helper functions that
can be called with the PCI bus semaphore held to avoid taking the read lock
twice.
Link: https://lore.kernel.org/r/ZZu0qx2cmn7IwTyQ@hovoldconsulting.com
Link: https://lore.kernel.org/r/20240130100243.11011-1-johan+linaro@kernel.org
Fixes: f93e71aea6c6 ("Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"")
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com>
Cc: <stable(a)vger.kernel.org> # 6.7
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 9c2137dae429..826b5016a101 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -386,21 +386,8 @@ void pci_bus_add_devices(const struct pci_bus *bus)
}
EXPORT_SYMBOL(pci_bus_add_devices);
-/** pci_walk_bus - walk devices on/under bus, calling callback.
- * @top bus whose devices should be walked
- * @cb callback to be called for each device found
- * @userdata arbitrary pointer to be passed to callback.
- *
- * Walk the given bus, including any bridged devices
- * on buses under this bus. Call the provided callback
- * on each device found.
- *
- * We check the return of @cb each time. If it returns anything
- * other than 0, we break out.
- *
- */
-void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
- void *userdata)
+static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
+ void *userdata, bool locked)
{
struct pci_dev *dev;
struct pci_bus *bus;
@@ -408,7 +395,8 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
int retval;
bus = top;
- down_read(&pci_bus_sem);
+ if (!locked)
+ down_read(&pci_bus_sem);
next = top->devices.next;
for (;;) {
if (next == &bus->devices) {
@@ -431,10 +419,37 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
if (retval)
break;
}
- up_read(&pci_bus_sem);
+ if (!locked)
+ up_read(&pci_bus_sem);
+}
+
+/**
+ * pci_walk_bus - walk devices on/under bus, calling callback.
+ * @top: bus whose devices should be walked
+ * @cb: callback to be called for each device found
+ * @userdata: arbitrary pointer to be passed to callback
+ *
+ * Walk the given bus, including any bridged devices
+ * on buses under this bus. Call the provided callback
+ * on each device found.
+ *
+ * We check the return of @cb each time. If it returns anything
+ * other than 0, we break out.
+ */
+void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
+{
+ __pci_walk_bus(top, cb, userdata, false);
}
EXPORT_SYMBOL_GPL(pci_walk_bus);
+void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
+{
+ lockdep_assert_held(&pci_bus_sem);
+
+ __pci_walk_bus(top, cb, userdata, true);
+}
+EXPORT_SYMBOL_GPL(pci_walk_bus_locked);
+
struct pci_bus *pci_bus_get(struct pci_bus *bus)
{
if (bus)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 10f2d0bb86be..2ce2a3bd932b 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -972,7 +972,7 @@ static int qcom_pcie_enable_aspm(struct pci_dev *pdev, void *userdata)
* Downstream devices need to be in D0 state before enabling PCI PM
* substates.
*/
- pci_set_power_state(pdev, PCI_D0);
+ pci_set_power_state_locked(pdev, PCI_D0);
pci_enable_link_state_locked(pdev, PCIE_LINK_STATE_ALL);
return 0;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index d8f11a078924..9ab9b1008d8b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1354,6 +1354,7 @@ int pci_power_up(struct pci_dev *dev)
/**
* pci_set_full_power_state - Put a PCI device into D0 and update its state
* @dev: PCI device to power up
+ * @locked: whether pci_bus_sem is held
*
* Call pci_power_up() to put @dev into D0, read from its PCI_PM_CTRL register
* to confirm the state change, restore its BARs if they might be lost and
@@ -1363,7 +1364,7 @@ int pci_power_up(struct pci_dev *dev)
* to D0, it is more efficient to use pci_power_up() directly instead of this
* function.
*/
-static int pci_set_full_power_state(struct pci_dev *dev)
+static int pci_set_full_power_state(struct pci_dev *dev, bool locked)
{
u16 pmcsr;
int ret;
@@ -1399,7 +1400,7 @@ static int pci_set_full_power_state(struct pci_dev *dev)
}
if (dev->bus->self)
- pcie_aspm_pm_state_change(dev->bus->self);
+ pcie_aspm_pm_state_change(dev->bus->self, locked);
return 0;
}
@@ -1428,10 +1429,22 @@ void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
pci_walk_bus(bus, __pci_dev_set_current_state, &state);
}
+static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state, bool locked)
+{
+ if (!bus)
+ return;
+
+ if (locked)
+ pci_walk_bus_locked(bus, __pci_dev_set_current_state, &state);
+ else
+ pci_walk_bus(bus, __pci_dev_set_current_state, &state);
+}
+
/**
* pci_set_low_power_state - Put a PCI device into a low-power state.
* @dev: PCI device to handle.
* @state: PCI power state (D1, D2, D3hot) to put the device into.
+ * @locked: whether pci_bus_sem is held
*
* Use the device's PCI_PM_CTRL register to put it into a low-power state.
*
@@ -1442,7 +1455,7 @@ void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
* 0 if device already is in the requested state.
* 0 if device's power state has been successfully changed.
*/
-static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state)
+static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state, bool locked)
{
u16 pmcsr;
@@ -1496,29 +1509,12 @@ static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state)
pci_power_name(state));
if (dev->bus->self)
- pcie_aspm_pm_state_change(dev->bus->self);
+ pcie_aspm_pm_state_change(dev->bus->self, locked);
return 0;
}
-/**
- * pci_set_power_state - Set the power state of a PCI device
- * @dev: PCI device to handle.
- * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
- *
- * Transition a device to a new power state, using the platform firmware and/or
- * the device's PCI PM registers.
- *
- * RETURN VALUE:
- * -EINVAL if the requested state is invalid.
- * -EIO if device does not support PCI PM or its PM capabilities register has a
- * wrong version, or device doesn't support the requested state.
- * 0 if the transition is to D1 or D2 but D1 and D2 are not supported.
- * 0 if device already is in the requested state.
- * 0 if the transition is to D3 but D3 is not supported.
- * 0 if device's power state has been successfully changed.
- */
-int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
+static int __pci_set_power_state(struct pci_dev *dev, pci_power_t state, bool locked)
{
int error;
@@ -1542,7 +1538,7 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
return 0;
if (state == PCI_D0)
- return pci_set_full_power_state(dev);
+ return pci_set_full_power_state(dev, locked);
/*
* This device is quirked not to be put into D3, so don't put it in
@@ -1556,16 +1552,16 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
* To put the device in D3cold, put it into D3hot in the native
* way, then put it into D3cold using platform ops.
*/
- error = pci_set_low_power_state(dev, PCI_D3hot);
+ error = pci_set_low_power_state(dev, PCI_D3hot, locked);
if (pci_platform_power_transition(dev, PCI_D3cold))
return error;
/* Powering off a bridge may power off the whole hierarchy */
if (dev->current_state == PCI_D3cold)
- pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
+ __pci_bus_set_current_state(dev->subordinate, PCI_D3cold, locked);
} else {
- error = pci_set_low_power_state(dev, state);
+ error = pci_set_low_power_state(dev, state, locked);
if (pci_platform_power_transition(dev, state))
return error;
@@ -1573,8 +1569,38 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
return 0;
}
+
+/**
+ * pci_set_power_state - Set the power state of a PCI device
+ * @dev: PCI device to handle.
+ * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
+ *
+ * Transition a device to a new power state, using the platform firmware and/or
+ * the device's PCI PM registers.
+ *
+ * RETURN VALUE:
+ * -EINVAL if the requested state is invalid.
+ * -EIO if device does not support PCI PM or its PM capabilities register has a
+ * wrong version, or device doesn't support the requested state.
+ * 0 if the transition is to D1 or D2 but D1 and D2 are not supported.
+ * 0 if device already is in the requested state.
+ * 0 if the transition is to D3 but D3 is not supported.
+ * 0 if device's power state has been successfully changed.
+ */
+int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
+{
+ return __pci_set_power_state(dev, state, false);
+}
EXPORT_SYMBOL(pci_set_power_state);
+int pci_set_power_state_locked(struct pci_dev *dev, pci_power_t state)
+{
+ lockdep_assert_held(&pci_bus_sem);
+
+ return __pci_set_power_state(dev, state, true);
+}
+EXPORT_SYMBOL(pci_set_power_state_locked);
+
#define PCI_EXP_SAVE_REGS 7
static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 2336a8d1edab..e9750b1b19ba 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -571,12 +571,12 @@ int pcie_retrain_link(struct pci_dev *pdev, bool use_lt);
#ifdef CONFIG_PCIEASPM
void pcie_aspm_init_link_state(struct pci_dev *pdev);
void pcie_aspm_exit_link_state(struct pci_dev *pdev);
-void pcie_aspm_pm_state_change(struct pci_dev *pdev);
+void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked);
void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
#else
static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { }
static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { }
-static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
+static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked) { }
static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
#endif
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 5a0066ecc3c5..bc0bd86695ec 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1003,8 +1003,11 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev)
up_read(&pci_bus_sem);
}
-/* @pdev: the root port or switch downstream port */
-void pcie_aspm_pm_state_change(struct pci_dev *pdev)
+/*
+ * @pdev: the root port or switch downstream port
+ * @locked: whether pci_bus_sem is held
+ */
+void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked)
{
struct pcie_link_state *link = pdev->link_state;
@@ -1014,12 +1017,14 @@ void pcie_aspm_pm_state_change(struct pci_dev *pdev)
* Devices changed PM state, we should recheck if latency
* meets all functions' requirement
*/
- down_read(&pci_bus_sem);
+ if (!locked)
+ down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
pcie_update_aspm_capable(link->root);
pcie_config_aspm_path(link);
mutex_unlock(&aspm_lock);
- up_read(&pci_bus_sem);
+ if (!locked)
+ up_read(&pci_bus_sem);
}
void pcie_aspm_powersave_config_link(struct pci_dev *pdev)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index add9368e6314..7ab0d13672da 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1422,6 +1422,7 @@ int pci_load_and_free_saved_state(struct pci_dev *dev,
struct pci_saved_state **state);
int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state);
int pci_set_power_state(struct pci_dev *dev, pci_power_t state);
+int pci_set_power_state_locked(struct pci_dev *dev, pci_power_t state);
pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state);
bool pci_pme_capable(struct pci_dev *dev, pci_power_t state);
void pci_pme_active(struct pci_dev *dev, bool enable);
@@ -1625,6 +1626,8 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
void *userdata);
+void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
+ void *userdata);
int pci_cfg_space_size(struct pci_dev *dev);
unsigned char pci_bus_max_busnr(struct pci_bus *bus);
void pci_setup_bridge(struct pci_bus *bus);
@@ -2025,6 +2028,8 @@ static inline int pci_save_state(struct pci_dev *dev) { return 0; }
static inline void pci_restore_state(struct pci_dev *dev) { }
static inline int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{ return 0; }
+static inline int pci_set_power_state_locked(struct pci_dev *dev, pci_power_t state)
+{ return 0; }
static inline int pci_wake_from_d3(struct pci_dev *dev, bool enable)
{ return 0; }
static inline pci_power_t pci_choose_state(struct pci_dev *dev,
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 1e560864159d002b453da42bd2c13a1805515a20
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024021328-stylus-ooze-f752@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
1e560864159d ("PCI/ASPM: Fix deadlock when enabling ASPM")
ac865f00af29 ("Merge tag 'pci-v6.7-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1e560864159d002b453da42bd2c13a1805515a20 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan+linaro(a)kernel.org>
Date: Tue, 30 Jan 2024 11:02:43 +0100
Subject: [PATCH] PCI/ASPM: Fix deadlock when enabling ASPM
A last minute revert in 6.7-final introduced a potential deadlock when
enabling ASPM during probe of Qualcomm PCIe controllers as reported by
lockdep:
============================================
WARNING: possible recursive locking detected
6.7.0 #40 Not tainted
--------------------------------------------
kworker/u16:5/90 is trying to acquire lock:
ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc
but task is already holding lock:
ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(pci_bus_sem);
lock(pci_bus_sem);
*** DEADLOCK ***
Call trace:
print_deadlock_bug+0x25c/0x348
__lock_acquire+0x10a4/0x2064
lock_acquire+0x1e8/0x318
down_read+0x60/0x184
pcie_aspm_pm_state_change+0x58/0xdc
pci_set_full_power_state+0xa8/0x114
pci_set_power_state+0xc4/0x120
qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom]
pci_walk_bus+0x64/0xbc
qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom]
The deadlock can easily be reproduced on machines like the Lenovo ThinkPad
X13s by adding a delay to increase the race window during asynchronous
probe where another thread can take a write lock.
Add a new pci_set_power_state_locked() and associated helper functions that
can be called with the PCI bus semaphore held to avoid taking the read lock
twice.
Link: https://lore.kernel.org/r/ZZu0qx2cmn7IwTyQ@hovoldconsulting.com
Link: https://lore.kernel.org/r/20240130100243.11011-1-johan+linaro@kernel.org
Fixes: f93e71aea6c6 ("Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"")
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com>
Cc: <stable(a)vger.kernel.org> # 6.7
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 9c2137dae429..826b5016a101 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -386,21 +386,8 @@ void pci_bus_add_devices(const struct pci_bus *bus)
}
EXPORT_SYMBOL(pci_bus_add_devices);
-/** pci_walk_bus - walk devices on/under bus, calling callback.
- * @top bus whose devices should be walked
- * @cb callback to be called for each device found
- * @userdata arbitrary pointer to be passed to callback.
- *
- * Walk the given bus, including any bridged devices
- * on buses under this bus. Call the provided callback
- * on each device found.
- *
- * We check the return of @cb each time. If it returns anything
- * other than 0, we break out.
- *
- */
-void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
- void *userdata)
+static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
+ void *userdata, bool locked)
{
struct pci_dev *dev;
struct pci_bus *bus;
@@ -408,7 +395,8 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
int retval;
bus = top;
- down_read(&pci_bus_sem);
+ if (!locked)
+ down_read(&pci_bus_sem);
next = top->devices.next;
for (;;) {
if (next == &bus->devices) {
@@ -431,10 +419,37 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
if (retval)
break;
}
- up_read(&pci_bus_sem);
+ if (!locked)
+ up_read(&pci_bus_sem);
+}
+
+/**
+ * pci_walk_bus - walk devices on/under bus, calling callback.
+ * @top: bus whose devices should be walked
+ * @cb: callback to be called for each device found
+ * @userdata: arbitrary pointer to be passed to callback
+ *
+ * Walk the given bus, including any bridged devices
+ * on buses under this bus. Call the provided callback
+ * on each device found.
+ *
+ * We check the return of @cb each time. If it returns anything
+ * other than 0, we break out.
+ */
+void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
+{
+ __pci_walk_bus(top, cb, userdata, false);
}
EXPORT_SYMBOL_GPL(pci_walk_bus);
+void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
+{
+ lockdep_assert_held(&pci_bus_sem);
+
+ __pci_walk_bus(top, cb, userdata, true);
+}
+EXPORT_SYMBOL_GPL(pci_walk_bus_locked);
+
struct pci_bus *pci_bus_get(struct pci_bus *bus)
{
if (bus)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 10f2d0bb86be..2ce2a3bd932b 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -972,7 +972,7 @@ static int qcom_pcie_enable_aspm(struct pci_dev *pdev, void *userdata)
* Downstream devices need to be in D0 state before enabling PCI PM
* substates.
*/
- pci_set_power_state(pdev, PCI_D0);
+ pci_set_power_state_locked(pdev, PCI_D0);
pci_enable_link_state_locked(pdev, PCIE_LINK_STATE_ALL);
return 0;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index d8f11a078924..9ab9b1008d8b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1354,6 +1354,7 @@ int pci_power_up(struct pci_dev *dev)
/**
* pci_set_full_power_state - Put a PCI device into D0 and update its state
* @dev: PCI device to power up
+ * @locked: whether pci_bus_sem is held
*
* Call pci_power_up() to put @dev into D0, read from its PCI_PM_CTRL register
* to confirm the state change, restore its BARs if they might be lost and
@@ -1363,7 +1364,7 @@ int pci_power_up(struct pci_dev *dev)
* to D0, it is more efficient to use pci_power_up() directly instead of this
* function.
*/
-static int pci_set_full_power_state(struct pci_dev *dev)
+static int pci_set_full_power_state(struct pci_dev *dev, bool locked)
{
u16 pmcsr;
int ret;
@@ -1399,7 +1400,7 @@ static int pci_set_full_power_state(struct pci_dev *dev)
}
if (dev->bus->self)
- pcie_aspm_pm_state_change(dev->bus->self);
+ pcie_aspm_pm_state_change(dev->bus->self, locked);
return 0;
}
@@ -1428,10 +1429,22 @@ void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
pci_walk_bus(bus, __pci_dev_set_current_state, &state);
}
+static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state, bool locked)
+{
+ if (!bus)
+ return;
+
+ if (locked)
+ pci_walk_bus_locked(bus, __pci_dev_set_current_state, &state);
+ else
+ pci_walk_bus(bus, __pci_dev_set_current_state, &state);
+}
+
/**
* pci_set_low_power_state - Put a PCI device into a low-power state.
* @dev: PCI device to handle.
* @state: PCI power state (D1, D2, D3hot) to put the device into.
+ * @locked: whether pci_bus_sem is held
*
* Use the device's PCI_PM_CTRL register to put it into a low-power state.
*
@@ -1442,7 +1455,7 @@ void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
* 0 if device already is in the requested state.
* 0 if device's power state has been successfully changed.
*/
-static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state)
+static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state, bool locked)
{
u16 pmcsr;
@@ -1496,29 +1509,12 @@ static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state)
pci_power_name(state));
if (dev->bus->self)
- pcie_aspm_pm_state_change(dev->bus->self);
+ pcie_aspm_pm_state_change(dev->bus->self, locked);
return 0;
}
-/**
- * pci_set_power_state - Set the power state of a PCI device
- * @dev: PCI device to handle.
- * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
- *
- * Transition a device to a new power state, using the platform firmware and/or
- * the device's PCI PM registers.
- *
- * RETURN VALUE:
- * -EINVAL if the requested state is invalid.
- * -EIO if device does not support PCI PM or its PM capabilities register has a
- * wrong version, or device doesn't support the requested state.
- * 0 if the transition is to D1 or D2 but D1 and D2 are not supported.
- * 0 if device already is in the requested state.
- * 0 if the transition is to D3 but D3 is not supported.
- * 0 if device's power state has been successfully changed.
- */
-int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
+static int __pci_set_power_state(struct pci_dev *dev, pci_power_t state, bool locked)
{
int error;
@@ -1542,7 +1538,7 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
return 0;
if (state == PCI_D0)
- return pci_set_full_power_state(dev);
+ return pci_set_full_power_state(dev, locked);
/*
* This device is quirked not to be put into D3, so don't put it in
@@ -1556,16 +1552,16 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
* To put the device in D3cold, put it into D3hot in the native
* way, then put it into D3cold using platform ops.
*/
- error = pci_set_low_power_state(dev, PCI_D3hot);
+ error = pci_set_low_power_state(dev, PCI_D3hot, locked);
if (pci_platform_power_transition(dev, PCI_D3cold))
return error;
/* Powering off a bridge may power off the whole hierarchy */
if (dev->current_state == PCI_D3cold)
- pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
+ __pci_bus_set_current_state(dev->subordinate, PCI_D3cold, locked);
} else {
- error = pci_set_low_power_state(dev, state);
+ error = pci_set_low_power_state(dev, state, locked);
if (pci_platform_power_transition(dev, state))
return error;
@@ -1573,8 +1569,38 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
return 0;
}
+
+/**
+ * pci_set_power_state - Set the power state of a PCI device
+ * @dev: PCI device to handle.
+ * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
+ *
+ * Transition a device to a new power state, using the platform firmware and/or
+ * the device's PCI PM registers.
+ *
+ * RETURN VALUE:
+ * -EINVAL if the requested state is invalid.
+ * -EIO if device does not support PCI PM or its PM capabilities register has a
+ * wrong version, or device doesn't support the requested state.
+ * 0 if the transition is to D1 or D2 but D1 and D2 are not supported.
+ * 0 if device already is in the requested state.
+ * 0 if the transition is to D3 but D3 is not supported.
+ * 0 if device's power state has been successfully changed.
+ */
+int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
+{
+ return __pci_set_power_state(dev, state, false);
+}
EXPORT_SYMBOL(pci_set_power_state);
+int pci_set_power_state_locked(struct pci_dev *dev, pci_power_t state)
+{
+ lockdep_assert_held(&pci_bus_sem);
+
+ return __pci_set_power_state(dev, state, true);
+}
+EXPORT_SYMBOL(pci_set_power_state_locked);
+
#define PCI_EXP_SAVE_REGS 7
static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 2336a8d1edab..e9750b1b19ba 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -571,12 +571,12 @@ int pcie_retrain_link(struct pci_dev *pdev, bool use_lt);
#ifdef CONFIG_PCIEASPM
void pcie_aspm_init_link_state(struct pci_dev *pdev);
void pcie_aspm_exit_link_state(struct pci_dev *pdev);
-void pcie_aspm_pm_state_change(struct pci_dev *pdev);
+void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked);
void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
#else
static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { }
static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { }
-static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
+static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked) { }
static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
#endif
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 5a0066ecc3c5..bc0bd86695ec 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1003,8 +1003,11 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev)
up_read(&pci_bus_sem);
}
-/* @pdev: the root port or switch downstream port */
-void pcie_aspm_pm_state_change(struct pci_dev *pdev)
+/*
+ * @pdev: the root port or switch downstream port
+ * @locked: whether pci_bus_sem is held
+ */
+void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked)
{
struct pcie_link_state *link = pdev->link_state;
@@ -1014,12 +1017,14 @@ void pcie_aspm_pm_state_change(struct pci_dev *pdev)
* Devices changed PM state, we should recheck if latency
* meets all functions' requirement
*/
- down_read(&pci_bus_sem);
+ if (!locked)
+ down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
pcie_update_aspm_capable(link->root);
pcie_config_aspm_path(link);
mutex_unlock(&aspm_lock);
- up_read(&pci_bus_sem);
+ if (!locked)
+ up_read(&pci_bus_sem);
}
void pcie_aspm_powersave_config_link(struct pci_dev *pdev)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index add9368e6314..7ab0d13672da 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1422,6 +1422,7 @@ int pci_load_and_free_saved_state(struct pci_dev *dev,
struct pci_saved_state **state);
int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state);
int pci_set_power_state(struct pci_dev *dev, pci_power_t state);
+int pci_set_power_state_locked(struct pci_dev *dev, pci_power_t state);
pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state);
bool pci_pme_capable(struct pci_dev *dev, pci_power_t state);
void pci_pme_active(struct pci_dev *dev, bool enable);
@@ -1625,6 +1626,8 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
void *userdata);
+void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
+ void *userdata);
int pci_cfg_space_size(struct pci_dev *dev);
unsigned char pci_bus_max_busnr(struct pci_bus *bus);
void pci_setup_bridge(struct pci_bus *bus);
@@ -2025,6 +2028,8 @@ static inline int pci_save_state(struct pci_dev *dev) { return 0; }
static inline void pci_restore_state(struct pci_dev *dev) { }
static inline int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{ return 0; }
+static inline int pci_set_power_state_locked(struct pci_dev *dev, pci_power_t state)
+{ return 0; }
static inline int pci_wake_from_d3(struct pci_dev *dev, bool enable)
{ return 0; }
static inline pci_power_t pci_choose_state(struct pci_dev *dev,
Hi,
We've got a collection of bug reports about how if a Thunderbolt device
is connected at bootup it doesn't behave the same as if it were
hotplugged by the user after bootup. Issues range from non-functional
devices or display devices working at lower performance.
All of the issues stem from a pre-OS firmware initializing the USB4
controller and the OS re-using those tunnels. This has been fixed in
6.9-rc1 by resetting the controller to a fresh state and discarding
whatever firmware has done. I'd like to bring it back to 6.6.y LTS and
6.8.y stable.
01da6b99d49f6 thunderbolt: Introduce tb_port_reset()
b35c1d7b11da8 thunderbolt: Introduce tb_path_deactivate_hop()
ec8162b3f0683 thunderbolt: Make tb_switch_reset() support Thunderbolt 2,
3 and USB4 routers
9a54c5f3dbde thunderbolt: Reset topology created by the boot firmware
Thanks!
From: Charles Keepax <ckeepax(a)opensource.cirrus.com>
[ Upstream commit 6588732445ff19f6183f0fa72ddedf67e5a5be32 ]
MIPS appears to define a RST symbol at a high level, which clashes
with some register naming in the driver. Since there is currently
no case for running this driver on MIPS devices simply cut off the
build of this driver on MIPS.
Reported-by: kernel test robot <lkp(a)intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311071303.JJMAOjy4-lkp@intel.com/
Suggested-by: Linus Walleij <linus.walleij(a)linaro.org>
Signed-off-by: Charles Keepax <ckeepax(a)opensource.cirrus.com>
Link: https://lore.kernel.org/r/20231115162853.1891940-1-ckeepax@opensource.cirru…
Signed-off-by: Linus Walleij <linus.walleij(a)linaro.org>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
drivers/pinctrl/cirrus/Kconfig | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/pinctrl/cirrus/Kconfig b/drivers/pinctrl/cirrus/Kconfig
index 530426a74f751..b3cea8d56c4f6 100644
--- a/drivers/pinctrl/cirrus/Kconfig
+++ b/drivers/pinctrl/cirrus/Kconfig
@@ -1,7 +1,8 @@
# SPDX-License-Identifier: GPL-2.0-only
config PINCTRL_LOCHNAGAR
tristate "Cirrus Logic Lochnagar pinctrl driver"
- depends on MFD_LOCHNAGAR
+ # Avoid clash caused by MIPS defining RST, which is used in the driver
+ depends on MFD_LOCHNAGAR && !MIPS
select GPIOLIB
select PINMUX
select PINCONF
--
2.42.0