From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- arch/mips/ath79/common.c | 149 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 149 insertions(+) create mode 100644 arch/mips/ath79/common.c (limited to 'arch/mips/ath79/common.c') diff --git a/arch/mips/ath79/common.c b/arch/mips/ath79/common.c new file mode 100644 index 000000000..137abbc65 --- /dev/null +++ b/arch/mips/ath79/common.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Atheros AR71XX/AR724X/AR913X common routines + * + * Copyright (C) 2010-2011 Jaiganesh Narayanan + * Copyright (C) 2008-2011 Gabor Juhos + * Copyright (C) 2008 Imre Kaloz + * + * Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP + */ + +#include +#include +#include +#include + +#include +#include +#include "common.h" + +static DEFINE_SPINLOCK(ath79_device_reset_lock); + +u32 ath79_cpu_freq; +EXPORT_SYMBOL_GPL(ath79_cpu_freq); + +u32 ath79_ahb_freq; +EXPORT_SYMBOL_GPL(ath79_ahb_freq); + +u32 ath79_ddr_freq; +EXPORT_SYMBOL_GPL(ath79_ddr_freq); + +enum ath79_soc_type ath79_soc; +unsigned int ath79_soc_rev; + +void __iomem *ath79_pll_base; +void __iomem *ath79_reset_base; +EXPORT_SYMBOL_GPL(ath79_reset_base); +static void __iomem *ath79_ddr_base; +static void __iomem *ath79_ddr_wb_flush_base; +static void __iomem *ath79_ddr_pci_win_base; + +void ath79_ddr_ctrl_init(void) +{ + ath79_ddr_base = ioremap(AR71XX_DDR_CTRL_BASE, + AR71XX_DDR_CTRL_SIZE); + if (soc_is_ar913x() || soc_is_ar724x() || soc_is_ar933x()) { + ath79_ddr_wb_flush_base = ath79_ddr_base + 0x7c; + ath79_ddr_pci_win_base = 0; + } else { + ath79_ddr_wb_flush_base = ath79_ddr_base + 0x9c; + ath79_ddr_pci_win_base = ath79_ddr_base + 0x7c; + } +} +EXPORT_SYMBOL_GPL(ath79_ddr_ctrl_init); + +void ath79_ddr_wb_flush(u32 reg) +{ + void __iomem *flush_reg = ath79_ddr_wb_flush_base + (reg * 4); + + /* Flush the DDR write buffer. */ + __raw_writel(0x1, flush_reg); + while (__raw_readl(flush_reg) & 0x1) + ; + + /* It must be run twice. */ + __raw_writel(0x1, flush_reg); + while (__raw_readl(flush_reg) & 0x1) + ; +} +EXPORT_SYMBOL_GPL(ath79_ddr_wb_flush); + +void ath79_ddr_set_pci_windows(void) +{ + BUG_ON(!ath79_ddr_pci_win_base); + + __raw_writel(AR71XX_PCI_WIN0_OFFS, ath79_ddr_pci_win_base + 0x0); + __raw_writel(AR71XX_PCI_WIN1_OFFS, ath79_ddr_pci_win_base + 0x4); + __raw_writel(AR71XX_PCI_WIN2_OFFS, ath79_ddr_pci_win_base + 0x8); + __raw_writel(AR71XX_PCI_WIN3_OFFS, ath79_ddr_pci_win_base + 0xc); + __raw_writel(AR71XX_PCI_WIN4_OFFS, ath79_ddr_pci_win_base + 0x10); + __raw_writel(AR71XX_PCI_WIN5_OFFS, ath79_ddr_pci_win_base + 0x14); + __raw_writel(AR71XX_PCI_WIN6_OFFS, ath79_ddr_pci_win_base + 0x18); + __raw_writel(AR71XX_PCI_WIN7_OFFS, ath79_ddr_pci_win_base + 0x1c); +} +EXPORT_SYMBOL_GPL(ath79_ddr_set_pci_windows); + +void ath79_device_reset_set(u32 mask) +{ + unsigned long flags; + u32 reg; + u32 t; + + if (soc_is_ar71xx()) + reg = AR71XX_RESET_REG_RESET_MODULE; + else if (soc_is_ar724x()) + reg = AR724X_RESET_REG_RESET_MODULE; + else if (soc_is_ar913x()) + reg = AR913X_RESET_REG_RESET_MODULE; + else if (soc_is_ar933x()) + reg = AR933X_RESET_REG_RESET_MODULE; + else if (soc_is_ar934x()) + reg = AR934X_RESET_REG_RESET_MODULE; + else if (soc_is_qca953x()) + reg = QCA953X_RESET_REG_RESET_MODULE; + else if (soc_is_qca955x()) + reg = QCA955X_RESET_REG_RESET_MODULE; + else if (soc_is_qca956x() || soc_is_tp9343()) + reg = QCA956X_RESET_REG_RESET_MODULE; + else + BUG(); + + spin_lock_irqsave(&ath79_device_reset_lock, flags); + t = ath79_reset_rr(reg); + ath79_reset_wr(reg, t | mask); + spin_unlock_irqrestore(&ath79_device_reset_lock, flags); +} +EXPORT_SYMBOL_GPL(ath79_device_reset_set); + +void ath79_device_reset_clear(u32 mask) +{ + unsigned long flags; + u32 reg; + u32 t; + + if (soc_is_ar71xx()) + reg = AR71XX_RESET_REG_RESET_MODULE; + else if (soc_is_ar724x()) + reg = AR724X_RESET_REG_RESET_MODULE; + else if (soc_is_ar913x()) + reg = AR913X_RESET_REG_RESET_MODULE; + else if (soc_is_ar933x()) + reg = AR933X_RESET_REG_RESET_MODULE; + else if (soc_is_ar934x()) + reg = AR934X_RESET_REG_RESET_MODULE; + else if (soc_is_qca953x()) + reg = QCA953X_RESET_REG_RESET_MODULE; + else if (soc_is_qca955x()) + reg = QCA955X_RESET_REG_RESET_MODULE; + else if (soc_is_qca956x() || soc_is_tp9343()) + reg = QCA956X_RESET_REG_RESET_MODULE; + else + BUG(); + + spin_lock_irqsave(&ath79_device_reset_lock, flags); + t = ath79_reset_rr(reg); + ath79_reset_wr(reg, t & ~mask); + spin_unlock_irqrestore(&ath79_device_reset_lock, flags); +} +EXPORT_SYMBOL_GPL(ath79_device_reset_clear); -- cgit v1.3.1