From c33fa9f5609e918824446ef9a75319d4a802f1f4 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 17 Apr 2008 20:05:36 +0200 Subject: uaccess: add probe_kernel_write() add probe_kernel_read() and probe_kernel_write(). Uninlined and restricted to kernel range memory only, as suggested by Linus. Signed-off-by: Ingo Molnar Reviewed-by: Thomas Gleixner --- include/linux/uaccess.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include/linux') diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 975c963e578..fec6decfb98 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -84,4 +84,26 @@ static inline unsigned long __copy_from_user_nocache(void *to, ret; \ }) +/* + * probe_kernel_read(): safely attempt to read from a location + * @dst: pointer to the buffer that shall take the data + * @src: address to read from + * @size: size of the data chunk + * + * Safely read from address @src to the buffer at @dst. If a kernel fault + * happens, handle that and return -EFAULT. + */ +extern long probe_kernel_read(void *dst, void *src, size_t size); + +/* + * probe_kernel_write(): safely attempt to write to a location + * @dst: address to write to + * @src: pointer to the data that shall be written + * @size: size of the data chunk + * + * Safely write to address @dst from the buffer at @src. If a kernel fault + * happens, handle that and return -EFAULT. + */ +extern long probe_kernel_write(void *dst, void *src, size_t size); + #endif /* __LINUX_UACCESS_H__ */ -- cgit v1.2.3 From dc7d552705215ac50a0617fcf51bb9c736255b8e Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 17 Apr 2008 20:05:37 +0200 Subject: kgdb: core kgdb core code. Handles the protocol and the arch details. [ mingo@elte.hu: heavily modified, simplified and cleaned up. ] [ xemul@openvz.org: use find_task_by_pid_ns ] Signed-off-by: Jason Wessel Signed-off-by: Ingo Molnar Signed-off-by: Jan Kiszka Reviewed-by: Thomas Gleixner --- include/linux/kgdb.h | 271 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 271 insertions(+) create mode 100644 include/linux/kgdb.h (limited to 'include/linux') diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h new file mode 100644 index 00000000000..b0985b79b63 --- /dev/null +++ b/include/linux/kgdb.h @@ -0,0 +1,271 @@ +/* + * This provides the callbacks and functions that KGDB needs to share between + * the core, I/O and arch-specific portions. + * + * Author: Amit Kale and + * Tom Rini + * + * 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc. + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ +#ifndef _KGDB_H_ +#define _KGDB_H_ + +#include +#include +#include + +#include +#include + +struct pt_regs; + +/* + * kgdb_skipexception - Bail out of KGDB when we've been triggered. + * @exception: Exception vector number + * @regs: Current &struct pt_regs. + * + * On some architectures we need to skip a breakpoint exception when + * it occurs after a breakpoint has been removed. + */ +extern int kgdb_skipexception(int exception, struct pt_regs *regs); + +/* + * kgdb_post_primary_code - Save error vector/code numbers. + * @regs: Original pt_regs. + * @e_vector: Original error vector. + * @err_code: Original error code. + * + * This is needed on architectures which support SMP and KGDB. + * This function is called after all the secondary cpus have been put + * to a know spin state and the primary CPU has control over KGDB. + */ +extern void kgdb_post_primary_code(struct pt_regs *regs, int e_vector, + int err_code); + +/* + * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb. + * @regs: Current &struct pt_regs. + * + * This function will be called if the particular architecture must + * disable hardware debugging while it is processing gdb packets or + * handling exception. + */ +extern void kgdb_disable_hw_debug(struct pt_regs *regs); + +struct tasklet_struct; +struct task_struct; +struct uart_port; + +/* To enter the debugger explicitly. */ +void kgdb_breakpoint(void); + +extern int kgdb_connected; + +extern atomic_t kgdb_setting_breakpoint; +extern atomic_t kgdb_cpu_doing_single_step; + +extern struct task_struct *kgdb_usethread; +extern struct task_struct *kgdb_contthread; + +enum kgdb_bptype { + BP_BREAKPOINT = 0, + BP_HARDWARE_BREAKPOINT, + BP_WRITE_WATCHPOINT, + BP_READ_WATCHPOINT, + BP_ACCESS_WATCHPOINT +}; + +enum kgdb_bpstate { + BP_UNDEFINED = 0, + BP_REMOVED, + BP_SET, + BP_ACTIVE +}; + +struct kgdb_bkpt { + unsigned long bpt_addr; + unsigned char saved_instr[BREAK_INSTR_SIZE]; + enum kgdb_bptype type; + enum kgdb_bpstate state; +}; + +#ifndef KGDB_MAX_BREAKPOINTS +# define KGDB_MAX_BREAKPOINTS 1000 +#endif + +#define KGDB_HW_BREAKPOINT 1 + +/* + * Functions each KGDB-supporting architecture must provide: + */ + +/* + * kgdb_arch_init - Perform any architecture specific initalization. + * + * This function will handle the initalization of any architecture + * specific callbacks. + */ +extern int kgdb_arch_init(void); + +/* + * kgdb_arch_exit - Perform any architecture specific uninitalization. + * + * This function will handle the uninitalization of any architecture + * specific callbacks, for dynamic registration and unregistration. + */ +extern void kgdb_arch_exit(void); + +/* + * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs + * @gdb_regs: A pointer to hold the registers in the order GDB wants. + * @regs: The &struct pt_regs of the current process. + * + * Convert the pt_regs in @regs into the format for registers that + * GDB expects, stored in @gdb_regs. + */ +extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs); + +/* + * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs + * @gdb_regs: A pointer to hold the registers in the order GDB wants. + * @p: The &struct task_struct of the desired process. + * + * Convert the register values of the sleeping process in @p to + * the format that GDB expects. + * This function is called when kgdb does not have access to the + * &struct pt_regs and therefore it should fill the gdb registers + * @gdb_regs with what has been saved in &struct thread_struct + * thread field during switch_to. + */ +extern void +sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p); + +/* + * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs. + * @gdb_regs: A pointer to hold the registers we've received from GDB. + * @regs: A pointer to a &struct pt_regs to hold these values in. + * + * Convert the GDB regs in @gdb_regs into the pt_regs, and store them + * in @regs. + */ +extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs); + +/* + * kgdb_arch_handle_exception - Handle architecture specific GDB packets. + * @vector: The error vector of the exception that happened. + * @signo: The signal number of the exception that happened. + * @err_code: The error code of the exception that happened. + * @remcom_in_buffer: The buffer of the packet we have read. + * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into. + * @regs: The &struct pt_regs of the current process. + * + * This function MUST handle the 'c' and 's' command packets, + * as well packets to set / remove a hardware breakpoint, if used. + * If there are additional packets which the hardware needs to handle, + * they are handled here. The code should return -1 if it wants to + * process more packets, and a %0 or %1 if it wants to exit from the + * kgdb callback. + */ +extern int +kgdb_arch_handle_exception(int vector, int signo, int err_code, + char *remcom_in_buffer, + char *remcom_out_buffer, + struct pt_regs *regs); + +/* + * kgdb_roundup_cpus - Get other CPUs into a holding pattern + * @flags: Current IRQ state + * + * On SMP systems, we need to get the attention of the other CPUs + * and get them be in a known state. This should do what is needed + * to get the other CPUs to call kgdb_wait(). Note that on some arches, + * the NMI approach is not used for rounding up all the CPUs. For example, + * in case of MIPS, smp_call_function() is used to roundup CPUs. In + * this case, we have to make sure that interrupts are enabled before + * calling smp_call_function(). The argument to this function is + * the flags that will be used when restoring the interrupts. There is + * local_irq_save() call before kgdb_roundup_cpus(). + * + * On non-SMP systems, this is not called. + */ +extern void kgdb_roundup_cpus(unsigned long flags); + +/* Optional functions. */ +extern int kgdb_validate_break_address(unsigned long addr); +extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr); +extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle); + +/* + * struct kgdb_arch - Describe architecture specific values. + * @gdb_bpt_instr: The instruction to trigger a breakpoint. + * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT. + * @set_breakpoint: Allow an architecture to specify how to set a software + * breakpoint. + * @remove_breakpoint: Allow an architecture to specify how to remove a + * software breakpoint. + * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware + * breakpoint. + * @remove_hw_breakpoint: Allow an architecture to specify how to remove a + * hardware breakpoint. + * @remove_all_hw_break: Allow an architecture to specify how to remove all + * hardware breakpoints. + * @correct_hw_break: Allow an architecture to specify how to correct the + * hardware debug registers. + */ +struct kgdb_arch { + unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE]; + unsigned long flags; + + int (*set_breakpoint)(unsigned long, char *); + int (*remove_breakpoint)(unsigned long, char *); + int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype); + int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype); + void (*remove_all_hw_break)(void); + void (*correct_hw_break)(void); +}; + +/* + * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB. + * @name: Name of the I/O driver. + * @read_char: Pointer to a function that will return one char. + * @write_char: Pointer to a function that will write one char. + * @flush: Pointer to a function that will flush any pending writes. + * @init: Pointer to a function that will initialize the device. + * @pre_exception: Pointer to a function that will do any prep work for + * the I/O driver. + * @post_exception: Pointer to a function that will do any cleanup work + * for the I/O driver. + */ +struct kgdb_io { + const char *name; + int (*read_char) (void); + void (*write_char) (u8); + void (*flush) (void); + int (*init) (void); + void (*pre_exception) (void); + void (*post_exception) (void); +}; + +extern struct kgdb_arch arch_kgdb_ops; + +extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops); +extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops); + +extern int kgdb_hex2long(char **ptr, long *long_val); +extern int kgdb_mem2hex(char *mem, char *buf, int count); +extern int kgdb_hex2mem(char *buf, char *mem, int count); + +extern int kgdb_isremovedbreak(unsigned long addr); + +extern int +kgdb_handle_exception(int ex_vector, int signo, int err_code, + struct pt_regs *regs); +extern int kgdb_nmicallback(int cpu, void *regs); + +extern int kgdb_single_step; +extern atomic_t kgdb_active; + +#endif /* _KGDB_H_ */ -- cgit v1.2.3 From f2d937f3bf00665ccf048b3b6616ef95859b0945 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 17 Apr 2008 20:05:37 +0200 Subject: consoles: polling support, kgdboc polled console handling support, to access a console in an irq-less way while in debug or irq context. absolutely zero impact as long as CONFIG_CONSOLE_POLL is disabled. (which is the default) [ jan.kiszka@siemens.com: lots of cleanups ] [ mingo@elte.hu: redesign, splitups, cleanups. ] Signed-off-by: Jason Wessel Signed-off-by: Ingo Molnar Signed-off-by: Jan Kiszka Reviewed-by: Thomas Gleixner --- include/linux/serial_core.h | 4 ++++ include/linux/tty_driver.h | 12 ++++++++++++ 2 files changed, 16 insertions(+) (limited to 'include/linux') diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 289942fc665..7cb094a8245 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -213,6 +213,10 @@ struct uart_ops { void (*config_port)(struct uart_port *, int); int (*verify_port)(struct uart_port *, struct serial_struct *); int (*ioctl)(struct uart_port *, unsigned int, unsigned long); +#ifdef CONFIG_CONSOLE_POLL + void (*poll_put_char)(struct uart_port *, unsigned char); + int (*poll_get_char)(struct uart_port *); +#endif }; #define UART_CONFIG_TYPE (1 << 0) diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h index 85c95cd39bc..21f69aca450 100644 --- a/include/linux/tty_driver.h +++ b/include/linux/tty_driver.h @@ -125,6 +125,7 @@ #include struct tty_struct; +struct tty_driver; struct tty_operations { int (*open)(struct tty_struct * tty, struct file * filp); @@ -157,6 +158,11 @@ struct tty_operations { int (*tiocmget)(struct tty_struct *tty, struct file *file); int (*tiocmset)(struct tty_struct *tty, struct file *file, unsigned int set, unsigned int clear); +#ifdef CONFIG_CONSOLE_POLL + int (*poll_init)(struct tty_driver *driver, int line, char *options); + int (*poll_get_char)(struct tty_driver *driver, int line); + void (*poll_put_char)(struct tty_driver *driver, int line, char ch); +#endif }; struct tty_driver { @@ -220,6 +226,11 @@ struct tty_driver { int (*tiocmget)(struct tty_struct *tty, struct file *file); int (*tiocmset)(struct tty_struct *tty, struct file *file, unsigned int set, unsigned int clear); +#ifdef CONFIG_CONSOLE_POLL + int (*poll_init)(struct tty_driver *driver, int line, char *options); + int (*poll_get_char)(struct tty_driver *driver, int line); + void (*poll_put_char)(struct tty_driver *driver, int line, char ch); +#endif struct list_head tty_drivers; }; @@ -230,6 +241,7 @@ struct tty_driver *alloc_tty_driver(int lines); void put_tty_driver(struct tty_driver *driver); void tty_set_operations(struct tty_driver *driver, const struct tty_operations *op); +extern struct tty_driver *tty_find_polling_driver(char *name, int *line); /* tty driver magic number */ #define TTY_DRIVER_MAGIC 0x5402 -- cgit v1.2.3 From 7c3078b637882303b1dcf6a16229d0e35f6b60a5 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Fri, 15 Feb 2008 14:55:54 -0600 Subject: kgdb: clocksource watchdog In order to not trip the clocksource watchdog, kgdb must touch the clocksource watchdog on the return to normal system run state. Signed-off-by: Jason Wessel Signed-off-by: Ingo Molnar --- include/linux/clocksource.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 85778a4b120..35094479ca5 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -216,6 +216,7 @@ static inline void clocksource_calculate_interval(struct clocksource *c, /* used to install a new clocksource */ extern int clocksource_register(struct clocksource*); extern void clocksource_unregister(struct clocksource*); +extern void clocksource_touch_watchdog(void); extern struct clocksource* clocksource_get_next(void); extern void clocksource_change_rating(struct clocksource *cs, int rating); extern void clocksource_resume(void); -- cgit v1.2.3 From e3e2aaf7dc0d82a055e084cfd48b9257c0c66b68 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 20 Mar 2008 13:43:45 -0500 Subject: kgdb: add documentation Add in the kgdb documentation for kgdb. Signed-off-by: Jason Wessel Signed-off-by: Ingo Molnar --- include/linux/kgdb.h | 52 +++++++++++++++++++++++++++++++--------------------- 1 file changed, 31 insertions(+), 21 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h index b0985b79b63..9757b1a6d9d 100644 --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -22,31 +22,34 @@ struct pt_regs; -/* - * kgdb_skipexception - Bail out of KGDB when we've been triggered. +/** + * kgdb_skipexception - (optional) exit kgdb_handle_exception early * @exception: Exception vector number * @regs: Current &struct pt_regs. * - * On some architectures we need to skip a breakpoint exception when - * it occurs after a breakpoint has been removed. + * On some architectures it is required to skip a breakpoint + * exception when it occurs after a breakpoint has been removed. + * This can be implemented in the architecture specific portion of + * for kgdb. */ extern int kgdb_skipexception(int exception, struct pt_regs *regs); -/* - * kgdb_post_primary_code - Save error vector/code numbers. +/** + * kgdb_post_primary_code - (optional) Save error vector/code numbers. * @regs: Original pt_regs. * @e_vector: Original error vector. * @err_code: Original error code. * - * This is needed on architectures which support SMP and KGDB. - * This function is called after all the secondary cpus have been put - * to a know spin state and the primary CPU has control over KGDB. + * This is usually needed on architectures which support SMP and + * KGDB. This function is called after all the secondary cpus have + * been put to a know spin state and the primary CPU has control over + * KGDB. */ extern void kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code); -/* - * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb. +/** + * kgdb_disable_hw_debug - (optional) Disable hardware debugging hook * @regs: Current &struct pt_regs. * * This function will be called if the particular architecture must @@ -59,7 +62,14 @@ struct tasklet_struct; struct task_struct; struct uart_port; -/* To enter the debugger explicitly. */ +/** + * kgdb_breakpoint - compiled in breakpoint + * + * This will be impelmented a static inline per architecture. This + * function is called by the kgdb core to execute an architecture + * specific trap to cause kgdb to enter the exception processing. + * + */ void kgdb_breakpoint(void); extern int kgdb_connected; @@ -102,7 +112,7 @@ struct kgdb_bkpt { * Functions each KGDB-supporting architecture must provide: */ -/* +/** * kgdb_arch_init - Perform any architecture specific initalization. * * This function will handle the initalization of any architecture @@ -110,7 +120,7 @@ struct kgdb_bkpt { */ extern int kgdb_arch_init(void); -/* +/** * kgdb_arch_exit - Perform any architecture specific uninitalization. * * This function will handle the uninitalization of any architecture @@ -118,7 +128,7 @@ extern int kgdb_arch_init(void); */ extern void kgdb_arch_exit(void); -/* +/** * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs * @gdb_regs: A pointer to hold the registers in the order GDB wants. * @regs: The &struct pt_regs of the current process. @@ -128,7 +138,7 @@ extern void kgdb_arch_exit(void); */ extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs); -/* +/** * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs * @gdb_regs: A pointer to hold the registers in the order GDB wants. * @p: The &struct task_struct of the desired process. @@ -143,7 +153,7 @@ extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs); extern void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p); -/* +/** * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs. * @gdb_regs: A pointer to hold the registers we've received from GDB. * @regs: A pointer to a &struct pt_regs to hold these values in. @@ -153,7 +163,7 @@ sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p); */ extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs); -/* +/** * kgdb_arch_handle_exception - Handle architecture specific GDB packets. * @vector: The error vector of the exception that happened. * @signo: The signal number of the exception that happened. @@ -175,7 +185,7 @@ kgdb_arch_handle_exception(int vector, int signo, int err_code, char *remcom_out_buffer, struct pt_regs *regs); -/* +/** * kgdb_roundup_cpus - Get other CPUs into a holding pattern * @flags: Current IRQ state * @@ -198,7 +208,7 @@ extern int kgdb_validate_break_address(unsigned long addr); extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr); extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle); -/* +/** * struct kgdb_arch - Describe architecture specific values. * @gdb_bpt_instr: The instruction to trigger a breakpoint. * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT. @@ -227,7 +237,7 @@ struct kgdb_arch { void (*correct_hw_break)(void); }; -/* +/** * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB. * @name: Name of the I/O driver. * @read_char: Pointer to a function that will return one char. -- cgit v1.2.3