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 --- drivers/clk/versatile/clk-versatile.c | 98 +++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) create mode 100644 drivers/clk/versatile/clk-versatile.c (limited to 'drivers/clk/versatile/clk-versatile.c') diff --git a/drivers/clk/versatile/clk-versatile.c b/drivers/clk/versatile/clk-versatile.c new file mode 100644 index 000000000..8ed7a179f --- /dev/null +++ b/drivers/clk/versatile/clk-versatile.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Clock driver for the ARM Integrator/AP, Integrator/CP, Versatile AB and + * Versatile PB boards. + * Copyright (C) 2012 Linus Walleij + */ +#include +#include +#include +#include + +#include "icst.h" +#include "clk-icst.h" + +#define INTEGRATOR_HDR_LOCK_OFFSET 0x14 + +#define VERSATILE_SYS_OSCCLCD_OFFSET 0x1c +#define VERSATILE_SYS_LOCK_OFFSET 0x20 + +/* Base offset for the core module */ +static void __iomem *cm_base; + +static const struct icst_params cp_auxosc_params = { + .vco_max = ICST525_VCO_MAX_5V, + .vco_min = ICST525_VCO_MIN, + .vd_min = 8, + .vd_max = 263, + .rd_min = 3, + .rd_max = 65, + .s2div = icst525_s2div, + .idx2s = icst525_idx2s, +}; + +static const struct clk_icst_desc cm_auxosc_desc __initconst = { + .params = &cp_auxosc_params, + .vco_offset = 0x1c, + .lock_offset = INTEGRATOR_HDR_LOCK_OFFSET, +}; + +static const struct icst_params versatile_auxosc_params = { + .vco_max = ICST307_VCO_MAX, + .vco_min = ICST307_VCO_MIN, + .vd_min = 4 + 8, + .vd_max = 511 + 8, + .rd_min = 1 + 2, + .rd_max = 127 + 2, + .s2div = icst307_s2div, + .idx2s = icst307_idx2s, +}; + +static const struct clk_icst_desc versatile_auxosc_desc __initconst = { + .params = &versatile_auxosc_params, + .vco_offset = VERSATILE_SYS_OSCCLCD_OFFSET, + .lock_offset = VERSATILE_SYS_LOCK_OFFSET, +}; +static void __init cm_osc_setup(struct device_node *np, + const struct clk_icst_desc *desc) +{ + struct clk *clk; + const char *clk_name = np->name; + const char *parent_name; + + if (!cm_base) { + /* Remap the core module base if not done yet */ + struct device_node *parent; + + parent = of_get_parent(np); + if (!parent) { + pr_err("no parent on core module clock\n"); + return; + } + cm_base = of_iomap(parent, 0); + of_node_put(parent); + if (!cm_base) { + pr_err("could not remap core module base\n"); + return; + } + } + + parent_name = of_clk_get_parent_name(np, 0); + clk = icst_clk_register(NULL, desc, clk_name, parent_name, cm_base); + if (!IS_ERR(clk)) + of_clk_add_provider(np, of_clk_src_simple_get, clk); +} + +static void __init of_integrator_cm_osc_setup(struct device_node *np) +{ + cm_osc_setup(np, &cm_auxosc_desc); +} +CLK_OF_DECLARE(integrator_cm_auxosc_clk, + "arm,integrator-cm-auxosc", of_integrator_cm_osc_setup); + +static void __init of_versatile_cm_osc_setup(struct device_node *np) +{ + cm_osc_setup(np, &versatile_auxosc_desc); +} +CLK_OF_DECLARE(versatile_cm_auxosc_clk, + "arm,versatile-cm-auxosc", of_versatile_cm_osc_setup); -- cgit v1.3.1