From 3f9c33333f6c3d4550b0b7dc607976bc416fa82d Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 23 Apr 2024 13:39:27 -0700 Subject: 6.1-stable patches added patches: pci-aspm-fix-deadlock-when-enabling-aspm.patch --- .../pci-aspm-fix-deadlock-when-enabling-aspm.patch | 388 +++++++++++++++++++++ queue-6.1/series | 1 + 2 files changed, 389 insertions(+) create mode 100644 queue-6.1/pci-aspm-fix-deadlock-when-enabling-aspm.patch diff --git a/queue-6.1/pci-aspm-fix-deadlock-when-enabling-aspm.patch b/queue-6.1/pci-aspm-fix-deadlock-when-enabling-aspm.patch new file mode 100644 index 0000000000..9eab132bf0 --- /dev/null +++ b/queue-6.1/pci-aspm-fix-deadlock-when-enabling-aspm.patch @@ -0,0 +1,388 @@ +From 1e560864159d002b453da42bd2c13a1805515a20 Mon Sep 17 00:00:00 2001 +From: Johan Hovold +Date: Tue, 30 Jan 2024 11:02:43 +0100 +Subject: PCI/ASPM: Fix deadlock when enabling ASPM + +From: Johan Hovold + +commit 1e560864159d002b453da42bd2c13a1805515a20 upstream. + +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 +Signed-off-by: Bjorn Helgaas +Cc: # 6.7 +[bhelgaas: backported to v6.1.y, which contains b9c370b61d73 ("Revert + "PCI/ASPM: Remove pcie_aspm_pm_state_change()""), a backport of + f93e71aea6c6. This omits the drivers/pci/controller/dwc/pcie-qcom.c hunk + that updates qcom_pcie_enable_aspm(), which was added by 9f4f3dfad8cf + ("PCI: qcom: Enable ASPM for platforms supporting 1.9.0 ops"), which is not + present in v6.1.87.] +Signed-off-by: Bjorn Helgaas +Signed-off-by: Greg Kroah-Hartman +--- + drivers/pci/bus.c | 49 +++++++++++++++++++----------- + drivers/pci/pci.c | 78 ++++++++++++++++++++++++++++++++---------------- + drivers/pci/pci.h | 4 +- + drivers/pci/pcie/aspm.c | 13 +++++--- + include/linux/pci.h | 5 +++ + 5 files changed, 100 insertions(+), 49 deletions(-) + +--- a/drivers/pci/bus.c ++++ b/drivers/pci/bus.c +@@ -379,21 +379,8 @@ void pci_bus_add_devices(const struct pc + } + 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; +@@ -401,7 +388,8 @@ void pci_walk_bus(struct pci_bus *top, i + 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) { +@@ -424,10 +412,37 @@ void pci_walk_bus(struct pci_bus *top, i + 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) +--- a/drivers/pci/pci.c ++++ b/drivers/pci/pci.c +@@ -1258,6 +1258,7 @@ end: + /** + * 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 +@@ -1267,7 +1268,7 @@ end: + * 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; +@@ -1303,7 +1304,7 @@ static int pci_set_full_power_state(stru + } + + if (dev->bus->self) +- pcie_aspm_pm_state_change(dev->bus->self); ++ pcie_aspm_pm_state_change(dev->bus->self, locked); + + return 0; + } +@@ -1332,10 +1333,22 @@ void pci_bus_set_current_state(struct pc + 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. + * +@@ -1346,7 +1359,7 @@ void pci_bus_set_current_state(struct pc + * 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; + +@@ -1400,29 +1413,12 @@ static int pci_set_low_power_state(struc + 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; + +@@ -1446,7 +1442,7 @@ int pci_set_power_state(struct pci_dev * + 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 +@@ -1460,16 +1456,16 @@ int pci_set_power_state(struct pci_dev * + * 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; +@@ -1477,8 +1473,38 @@ int pci_set_power_state(struct pci_dev * + + 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, +--- a/drivers/pci/pci.h ++++ b/drivers/pci/pci.h +@@ -556,12 +556,12 @@ bool pcie_wait_for_link(struct pci_dev * + #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 + +--- a/drivers/pci/pcie/aspm.c ++++ b/drivers/pci/pcie/aspm.c +@@ -1055,8 +1055,11 @@ void pcie_aspm_exit_link_state(struct pc + 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; + +@@ -1066,12 +1069,14 @@ void pcie_aspm_pm_state_change(struct pc + * 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) +--- a/include/linux/pci.h ++++ b/include/linux/pci.h +@@ -1383,6 +1383,7 @@ int pci_load_and_free_saved_state(struct + 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); +@@ -1553,6 +1554,8 @@ int pci_scan_bridge(struct pci_bus *bus, + + 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); +@@ -1884,6 +1887,8 @@ static inline int pci_save_state(struct + 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, diff --git a/queue-6.1/series b/queue-6.1/series index 558a2bfe8f..42d2913c83 100644 --- a/queue-6.1/series +++ b/queue-6.1/series @@ -138,3 +138,4 @@ ksmbd-fix-slab-out-of-bounds-in-smb2_allocate_rsp_buf.patch ksmbd-validate-request-buffer-size-in-smb2_allocate_rsp_buf.patch ksmbd-clear-rename_noreplace-before-calling-vfs_rename.patch ksmbd-common-use-struct_group_attr-instead-of-struct_group-for-network_open_info.patch +pci-aspm-fix-deadlock-when-enabling-aspm.patch -- cgit 1.2.3-korg