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/video/fbdev/savage/Makefile | 10 + drivers/video/fbdev/savage/savagefb-i2c.c | 241 +++ drivers/video/fbdev/savage/savagefb.h | 406 ++++ drivers/video/fbdev/savage/savagefb_accel.c | 137 ++ drivers/video/fbdev/savage/savagefb_driver.c | 2579 ++++++++++++++++++++++++++ 5 files changed, 3373 insertions(+) create mode 100644 drivers/video/fbdev/savage/Makefile create mode 100644 drivers/video/fbdev/savage/savagefb-i2c.c create mode 100644 drivers/video/fbdev/savage/savagefb.h create mode 100644 drivers/video/fbdev/savage/savagefb_accel.c create mode 100644 drivers/video/fbdev/savage/savagefb_driver.c (limited to 'drivers/video/fbdev/savage') diff --git a/drivers/video/fbdev/savage/Makefile b/drivers/video/fbdev/savage/Makefile new file mode 100644 index 000000000..3f6fcced1 --- /dev/null +++ b/drivers/video/fbdev/savage/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for the S3 Savage framebuffer driver +# + +obj-$(CONFIG_FB_SAVAGE) += savagefb.o + +savagefb-y += savagefb_driver.o +savagefb-$(CONFIG_FB_SAVAGE_I2C) += savagefb-i2c.o +savagefb-$(CONFIG_FB_SAVAGE_ACCEL) += savagefb_accel.o diff --git a/drivers/video/fbdev/savage/savagefb-i2c.c b/drivers/video/fbdev/savage/savagefb-i2c.c new file mode 100644 index 000000000..80fa87e2a --- /dev/null +++ b/drivers/video/fbdev/savage/savagefb-i2c.c @@ -0,0 +1,241 @@ +/* + * linux/drivers/video/savage/savagefb-i2c.c - S3 Savage DDC2 + * + * Copyright 2004 Antonino A. Daplas + * + * Based partly on rivafb-i2c.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +#include +#include +#include +#include +#include +#include + +#include +#include "savagefb.h" + +#define SAVAGE_DDC 0x50 + +#define VGA_CR_IX 0x3d4 +#define VGA_CR_DATA 0x3d5 + +#define CR_SERIAL1 0xa0 /* I2C serial communications interface */ +#define MM_SERIAL1 0xff20 +#define CR_SERIAL2 0xb1 /* DDC2 monitor communications interface */ + +/* based on vt8365 documentation */ +#define PROSAVAGE_I2C_ENAB 0x10 +#define PROSAVAGE_I2C_SCL_OUT 0x01 +#define PROSAVAGE_I2C_SDA_OUT 0x02 +#define PROSAVAGE_I2C_SCL_IN 0x04 +#define PROSAVAGE_I2C_SDA_IN 0x08 + +#define SAVAGE4_I2C_ENAB 0x00000020 +#define SAVAGE4_I2C_SCL_OUT 0x00000001 +#define SAVAGE4_I2C_SDA_OUT 0x00000002 +#define SAVAGE4_I2C_SCL_IN 0x00000008 +#define SAVAGE4_I2C_SDA_IN 0x00000010 + +static void savage4_gpio_setscl(void *data, int val) +{ + struct savagefb_i2c_chan *chan = data; + unsigned int r; + + r = readl(chan->ioaddr + chan->reg); + if(val) + r |= SAVAGE4_I2C_SCL_OUT; + else + r &= ~SAVAGE4_I2C_SCL_OUT; + writel(r, chan->ioaddr + chan->reg); + readl(chan->ioaddr + chan->reg); /* flush posted write */ +} + +static void savage4_gpio_setsda(void *data, int val) +{ + struct savagefb_i2c_chan *chan = data; + + unsigned int r; + r = readl(chan->ioaddr + chan->reg); + if(val) + r |= SAVAGE4_I2C_SDA_OUT; + else + r &= ~SAVAGE4_I2C_SDA_OUT; + writel(r, chan->ioaddr + chan->reg); + readl(chan->ioaddr + chan->reg); /* flush posted write */ +} + +static int savage4_gpio_getscl(void *data) +{ + struct savagefb_i2c_chan *chan = data; + + return (0 != (readl(chan->ioaddr + chan->reg) & SAVAGE4_I2C_SCL_IN)); +} + +static int savage4_gpio_getsda(void *data) +{ + struct savagefb_i2c_chan *chan = data; + + return (0 != (readl(chan->ioaddr + chan->reg) & SAVAGE4_I2C_SDA_IN)); +} + +static void prosavage_gpio_setscl(void* data, int val) +{ + struct savagefb_i2c_chan *chan = data; + u32 r; + + r = VGArCR(chan->reg, chan->par); + r |= PROSAVAGE_I2C_ENAB; + if (val) { + r |= PROSAVAGE_I2C_SCL_OUT; + } else { + r &= ~PROSAVAGE_I2C_SCL_OUT; + } + + VGAwCR(chan->reg, r, chan->par); +} + +static void prosavage_gpio_setsda(void* data, int val) +{ + struct savagefb_i2c_chan *chan = data; + unsigned int r; + + r = VGArCR(chan->reg, chan->par); + r |= PROSAVAGE_I2C_ENAB; + if (val) { + r |= PROSAVAGE_I2C_SDA_OUT; + } else { + r &= ~PROSAVAGE_I2C_SDA_OUT; + } + + VGAwCR(chan->reg, r, chan->par); +} + +static int prosavage_gpio_getscl(void* data) +{ + struct savagefb_i2c_chan *chan = data; + + return (VGArCR(chan->reg, chan->par) & PROSAVAGE_I2C_SCL_IN) ? 1 : 0; +} + +static int prosavage_gpio_getsda(void* data) +{ + struct savagefb_i2c_chan *chan = data; + + return (VGArCR(chan->reg, chan->par) & PROSAVAGE_I2C_SDA_IN) ? 1 : 0; +} + +static int savage_setup_i2c_bus(struct savagefb_i2c_chan *chan, + const char *name) +{ + int rc = 0; + + if (chan->par) { + strcpy(chan->adapter.name, name); + chan->adapter.owner = THIS_MODULE; + chan->adapter.algo_data = &chan->algo; + chan->adapter.dev.parent = &chan->par->pcidev->dev; + chan->algo.udelay = 10; + chan->algo.timeout = 20; + chan->algo.data = chan; + + i2c_set_adapdata(&chan->adapter, chan); + + /* Raise SCL and SDA */ + chan->algo.setsda(chan, 1); + chan->algo.setscl(chan, 1); + udelay(20); + + rc = i2c_bit_add_bus(&chan->adapter); + + if (rc == 0) + dev_dbg(&chan->par->pcidev->dev, + "I2C bus %s registered.\n", name); + else + dev_warn(&chan->par->pcidev->dev, + "Failed to register I2C bus %s.\n", name); + } + + return rc; +} + +void savagefb_create_i2c_busses(struct fb_info *info) +{ + struct savagefb_par *par = info->par; + par->chan.par = par; + + switch (par->chip) { + case S3_PROSAVAGE: + case S3_PROSAVAGEDDR: + case S3_TWISTER: + par->chan.reg = CR_SERIAL2; + par->chan.ioaddr = par->mmio.vbase; + par->chan.algo.setsda = prosavage_gpio_setsda; + par->chan.algo.setscl = prosavage_gpio_setscl; + par->chan.algo.getsda = prosavage_gpio_getsda; + par->chan.algo.getscl = prosavage_gpio_getscl; + break; + case S3_SAVAGE4: + par->chan.reg = CR_SERIAL1; + if (par->pcidev->revision > 1 && !(VGArCR(0xa6, par) & 0x40)) + par->chan.reg = CR_SERIAL2; + par->chan.ioaddr = par->mmio.vbase; + par->chan.algo.setsda = prosavage_gpio_setsda; + par->chan.algo.setscl = prosavage_gpio_setscl; + par->chan.algo.getsda = prosavage_gpio_getsda; + par->chan.algo.getscl = prosavage_gpio_getscl; + break; + case S3_SAVAGE2000: + par->chan.reg = MM_SERIAL1; + par->chan.ioaddr = par->mmio.vbase; + par->chan.algo.setsda = savage4_gpio_setsda; + par->chan.algo.setscl = savage4_gpio_setscl; + par->chan.algo.getsda = savage4_gpio_getsda; + par->chan.algo.getscl = savage4_gpio_getscl; + break; + default: + par->chan.par = NULL; + } + + savage_setup_i2c_bus(&par->chan, "SAVAGE DDC2"); +} + +void savagefb_delete_i2c_busses(struct fb_info *info) +{ + struct savagefb_par *par = info->par; + + if (par->chan.par) + i2c_del_adapter(&par->chan.adapter); + + par->chan.par = NULL; +} + +int savagefb_probe_i2c_connector(struct fb_info *info, u8 **out_edid) +{ + struct savagefb_par *par = info->par; + u8 *edid; + + if (par->chan.par) + edid = fb_ddc_read(&par->chan.adapter); + else + edid = NULL; + + if (!edid) { + /* try to get from firmware */ + const u8 *e = fb_firmware_edid(info->device); + + if (e) + edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL); + } + + *out_edid = edid; + + return (edid) ? 0 : 1; +} + +MODULE_LICENSE("GPL"); diff --git a/drivers/video/fbdev/savage/savagefb.h b/drivers/video/fbdev/savage/savagefb.h new file mode 100644 index 000000000..b6b8cc208 --- /dev/null +++ b/drivers/video/fbdev/savage/savagefb.h @@ -0,0 +1,406 @@ +/* + * linux/drivers/video/savagefb.h -- S3 Savage Framebuffer Driver + * + * Copyright (c) 2001 Denis Oliver Kropp + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. + */ + + +#ifndef __SAVAGEFB_H__ +#define __SAVAGEFB_H__ + +#include +#include +#include +#include