+++ /dev/null
-From ac9ca8a06f060318966c312bf9a5bd554dc392fb Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Wed, 29 Sep 2021 15:02:14 -0700
-Subject: sched: Add wrapper for get_wchan() to keep task blocked
-
-From: Kees Cook <keescook@chromium.org>
-
-[ Upstream commit 42a20f86dc19f9282d974df0ba4d226c865ab9dd ]
-
-Having a stable wchan means the process must be blocked and for it to
-stay that way while performing stack unwinding.
-
-Suggested-by: Peter Zijlstra <peterz@infradead.org>
-Signed-off-by: Kees Cook <keescook@chromium.org>
-Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
-Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
-Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm]
-Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64]
-Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org
-Signed-off-by: Sasha Levin <sashal@kernel.org>
----
- arch/alpha/include/asm/processor.h | 2 +-
- arch/alpha/kernel/process.c | 5 ++---
- arch/arc/include/asm/processor.h | 2 +-
- arch/arc/kernel/stacktrace.c | 4 ++--
- arch/arm/include/asm/processor.h | 2 +-
- arch/arm/kernel/process.c | 4 +---
- arch/arm64/include/asm/processor.h | 2 +-
- arch/arm64/kernel/process.c | 4 +---
- arch/csky/include/asm/processor.h | 2 +-
- arch/csky/kernel/stacktrace.c | 5 ++---
- arch/h8300/include/asm/processor.h | 2 +-
- arch/h8300/kernel/process.c | 5 +----
- arch/hexagon/include/asm/processor.h | 2 +-
- arch/hexagon/kernel/process.c | 4 +---
- arch/ia64/include/asm/processor.h | 2 +-
- arch/ia64/kernel/process.c | 5 +----
- arch/m68k/include/asm/processor.h | 2 +-
- arch/m68k/kernel/process.c | 4 +---
- arch/microblaze/include/asm/processor.h | 2 +-
- arch/microblaze/kernel/process.c | 2 +-
- arch/mips/include/asm/processor.h | 2 +-
- arch/mips/kernel/process.c | 8 +++-----
- arch/nds32/include/asm/processor.h | 2 +-
- arch/nds32/kernel/process.c | 7 +------
- arch/nios2/include/asm/processor.h | 2 +-
- arch/nios2/kernel/process.c | 5 +----
- arch/openrisc/include/asm/processor.h | 2 +-
- arch/openrisc/kernel/process.c | 2 +-
- arch/parisc/include/asm/processor.h | 2 +-
- arch/parisc/kernel/process.c | 5 +----
- arch/powerpc/include/asm/processor.h | 2 +-
- arch/powerpc/kernel/process.c | 9 +++------
- arch/riscv/include/asm/processor.h | 2 +-
- arch/riscv/kernel/stacktrace.c | 12 +++++-------
- arch/s390/include/asm/processor.h | 2 +-
- arch/s390/kernel/process.c | 4 ++--
- arch/sh/include/asm/processor_32.h | 2 +-
- arch/sh/kernel/process_32.c | 5 +----
- arch/sparc/include/asm/processor_32.h | 2 +-
- arch/sparc/include/asm/processor_64.h | 2 +-
- arch/sparc/kernel/process_32.c | 5 +----
- arch/sparc/kernel/process_64.c | 5 +----
- arch/um/include/asm/processor-generic.h | 2 +-
- arch/um/kernel/process.c | 5 +----
- arch/x86/include/asm/processor.h | 2 +-
- arch/x86/kernel/process.c | 5 +----
- arch/xtensa/include/asm/processor.h | 2 +-
- arch/xtensa/kernel/process.c | 5 +----
- include/linux/sched.h | 1 +
- kernel/sched/core.c | 19 +++++++++++++++++++
- 50 files changed, 80 insertions(+), 112 deletions(-)
-
-diff --git a/arch/alpha/include/asm/processor.h b/arch/alpha/include/asm/processor.h
-index 6100431da07a3..090499c99c1c1 100644
---- a/arch/alpha/include/asm/processor.h
-+++ b/arch/alpha/include/asm/processor.h
-@@ -42,7 +42,7 @@ extern void start_thread(struct pt_regs *, unsigned long, unsigned long);
- struct task_struct;
- extern void release_thread(struct task_struct *);
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
-
-diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
-index a5123ea426ce5..5f8527081da92 100644
---- a/arch/alpha/kernel/process.c
-+++ b/arch/alpha/kernel/process.c
-@@ -376,12 +376,11 @@ thread_saved_pc(struct task_struct *t)
- }
-
- unsigned long
--get_wchan(struct task_struct *p)
-+__get_wchan(struct task_struct *p)
- {
- unsigned long schedule_frame;
- unsigned long pc;
-- if (!p || p == current || task_is_running(p))
-- return 0;
-+
- /*
- * This one depends on the frame size of schedule(). Do a
- * "disass schedule" in gdb to find the frame size. Also, the
-diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h
-index f28afcf5c6d10..54db9d7bb562d 100644
---- a/arch/arc/include/asm/processor.h
-+++ b/arch/arc/include/asm/processor.h
-@@ -70,7 +70,7 @@ struct task_struct;
- extern void start_thread(struct pt_regs * regs, unsigned long pc,
- unsigned long usp);
-
--extern unsigned int get_wchan(struct task_struct *p);
-+extern unsigned int __get_wchan(struct task_struct *p);
-
- #endif /* !__ASSEMBLY__ */
-
-diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c
-index c376ff3147e7b..5372dc04e7847 100644
---- a/arch/arc/kernel/stacktrace.c
-+++ b/arch/arc/kernel/stacktrace.c
-@@ -15,7 +15,7 @@
- * = specifics of data structs where trace is saved(CONFIG_STACKTRACE etc)
- *
- * vineetg: March 2009
-- * -Implemented correct versions of thread_saved_pc() and get_wchan()
-+ * -Implemented correct versions of thread_saved_pc() and __get_wchan()
- *
- * rajeshwarr: 2008
- * -Initial implementation
-@@ -248,7 +248,7 @@ void show_stack(struct task_struct *tsk, unsigned long *sp, const char *loglvl)
- * Of course just returning schedule( ) would be pointless so unwind until
- * the function is not in schedular code
- */
--unsigned int get_wchan(struct task_struct *tsk)
-+unsigned int __get_wchan(struct task_struct *tsk)
- {
- return arc_unwind_core(tsk, NULL, __get_first_nonsched, NULL);
- }
-diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h
-index 9e6b972863077..6af68edfa53ab 100644
---- a/arch/arm/include/asm/processor.h
-+++ b/arch/arm/include/asm/processor.h
-@@ -84,7 +84,7 @@ struct task_struct;
- /* Free all resources held by a thread. */
- extern void release_thread(struct task_struct *);
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define task_pt_regs(p) \
- ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
-diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
-index 0e2d3051741ed..96f577e59595f 100644
---- a/arch/arm/kernel/process.c
-+++ b/arch/arm/kernel/process.c
-@@ -276,13 +276,11 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
- return 0;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- struct stackframe frame;
- unsigned long stack_page;
- int count = 0;
-- if (!p || p == current || task_is_running(p))
-- return 0;
-
- frame.fp = thread_saved_fp(p);
- frame.sp = thread_saved_sp(p);
-diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
-index ee2bdc1b9f5bb..55ca034238eae 100644
---- a/arch/arm64/include/asm/processor.h
-+++ b/arch/arm64/include/asm/processor.h
-@@ -257,7 +257,7 @@ struct task_struct;
- /* Free all resources held by a thread. */
- extern void release_thread(struct task_struct *);
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- void update_sctlr_el1(u64 sctlr);
-
-diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
-index 40adb8cdbf5af..aacf2f5559a8b 100644
---- a/arch/arm64/kernel/process.c
-+++ b/arch/arm64/kernel/process.c
-@@ -528,13 +528,11 @@ __notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev,
- return last;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- struct stackframe frame;
- unsigned long stack_page, ret = 0;
- int count = 0;
-- if (!p || p == current || task_is_running(p))
-- return 0;
-
- stack_page = (unsigned long)try_get_task_stack(p);
- if (!stack_page)
-diff --git a/arch/csky/include/asm/processor.h b/arch/csky/include/asm/processor.h
-index 9e933021fe8e0..817dd60ff152d 100644
---- a/arch/csky/include/asm/processor.h
-+++ b/arch/csky/include/asm/processor.h
-@@ -81,7 +81,7 @@ static inline void release_thread(struct task_struct *dead_task)
-
- extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
- #define KSTK_ESP(tsk) (task_pt_regs(tsk)->usp)
-diff --git a/arch/csky/kernel/stacktrace.c b/arch/csky/kernel/stacktrace.c
-index 1b280ef080045..9f78f5d215117 100644
---- a/arch/csky/kernel/stacktrace.c
-+++ b/arch/csky/kernel/stacktrace.c
-@@ -111,12 +111,11 @@ static bool save_wchan(unsigned long pc, void *arg)
- return false;
- }
-
--unsigned long get_wchan(struct task_struct *task)
-+unsigned long __get_wchan(struct task_struct *task)
- {
- unsigned long pc = 0;
-
-- if (likely(task && task != current && !task_is_running(task)))
-- walk_stackframe(task, NULL, save_wchan, &pc);
-+ walk_stackframe(task, NULL, save_wchan, &pc);
- return pc;
- }
-
-diff --git a/arch/h8300/include/asm/processor.h b/arch/h8300/include/asm/processor.h
-index a060b41b2d31c..141a23eb62b74 100644
---- a/arch/h8300/include/asm/processor.h
-+++ b/arch/h8300/include/asm/processor.h
-@@ -105,7 +105,7 @@ static inline void release_thread(struct task_struct *dead_task)
- {
- }
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) \
- ({ \
-diff --git a/arch/h8300/kernel/process.c b/arch/h8300/kernel/process.c
-index 2ac27e4248a46..8833fa4f5d516 100644
---- a/arch/h8300/kernel/process.c
-+++ b/arch/h8300/kernel/process.c
-@@ -128,15 +128,12 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
- return 0;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long fp, pc;
- unsigned long stack_page;
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- stack_page = (unsigned long)p;
- fp = ((struct pt_regs *)p->thread.ksp)->er6;
- do {
-diff --git a/arch/hexagon/include/asm/processor.h b/arch/hexagon/include/asm/processor.h
-index 9f0cc99420bee..615f7e49968e6 100644
---- a/arch/hexagon/include/asm/processor.h
-+++ b/arch/hexagon/include/asm/processor.h
-@@ -64,7 +64,7 @@ struct thread_struct {
- extern void release_thread(struct task_struct *dead_task);
-
- /* Get wait channel for task P. */
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
- /* The following stuff is pretty HEXAGON specific. */
-
-diff --git a/arch/hexagon/kernel/process.c b/arch/hexagon/kernel/process.c
-index 6a6835fb42425..232dfd8956aa2 100644
---- a/arch/hexagon/kernel/process.c
-+++ b/arch/hexagon/kernel/process.c
-@@ -130,13 +130,11 @@ void flush_thread(void)
- * is an identification of the point at which the scheduler
- * was invoked by a blocked thread.
- */
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long fp, pc;
- unsigned long stack_page;
- int count = 0;
-- if (!p || p == current || task_is_running(p))
-- return 0;
-
- stack_page = (unsigned long)task_stack_page(p);
- fp = ((struct hexagon_switch_stack *)p->thread.switch_sp)->fp;
-diff --git a/arch/ia64/include/asm/processor.h b/arch/ia64/include/asm/processor.h
-index 2d8bcdc27d7f8..45365c2ef5983 100644
---- a/arch/ia64/include/asm/processor.h
-+++ b/arch/ia64/include/asm/processor.h
-@@ -330,7 +330,7 @@ struct task_struct;
- #define release_thread(dead_task)
-
- /* Get wait channel for task P. */
--extern unsigned long get_wchan (struct task_struct *p);
-+extern unsigned long __get_wchan (struct task_struct *p);
-
- /* Return instruction pointer of blocked task TSK. */
- #define KSTK_EIP(tsk) \
-diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
-index e56d63f4abf9d..834df24a88f12 100644
---- a/arch/ia64/kernel/process.c
-+++ b/arch/ia64/kernel/process.c
-@@ -523,15 +523,12 @@ exit_thread (struct task_struct *tsk)
- }
-
- unsigned long
--get_wchan (struct task_struct *p)
-+__get_wchan (struct task_struct *p)
- {
- struct unw_frame_info info;
- unsigned long ip;
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- /*
- * Note: p may not be a blocked task (it could be current or
- * another process running on some other CPU. Rather than
-diff --git a/arch/m68k/include/asm/processor.h b/arch/m68k/include/asm/processor.h
-index f4d82c619a5c4..ffeda9aa526a5 100644
---- a/arch/m68k/include/asm/processor.h
-+++ b/arch/m68k/include/asm/processor.h
-@@ -150,7 +150,7 @@ static inline void release_thread(struct task_struct *dead_task)
- {
- }
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) \
- ({ \
-diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c
-index 1ab692b952cd6..a6030dbaa0891 100644
---- a/arch/m68k/kernel/process.c
-+++ b/arch/m68k/kernel/process.c
-@@ -263,13 +263,11 @@ int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
- }
- EXPORT_SYMBOL(dump_fpu);
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long fp, pc;
- unsigned long stack_page;
- int count = 0;
-- if (!p || p == current || task_is_running(p))
-- return 0;
-
- stack_page = (unsigned long)task_stack_page(p);
- fp = ((struct switch_stack *)p->thread.ksp)->a6;
-diff --git a/arch/microblaze/include/asm/processor.h b/arch/microblaze/include/asm/processor.h
-index 06c6e493590a2..7e9e92670df33 100644
---- a/arch/microblaze/include/asm/processor.h
-+++ b/arch/microblaze/include/asm/processor.h
-@@ -68,7 +68,7 @@ static inline void release_thread(struct task_struct *dead_task)
- {
- }
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- /* The size allocated for kernel stacks. This _must_ be a power of two! */
- # define KERNEL_STACK_SIZE 0x2000
-diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c
-index 62aa237180b67..5e2b91c1e8ced 100644
---- a/arch/microblaze/kernel/process.c
-+++ b/arch/microblaze/kernel/process.c
-@@ -112,7 +112,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
- return 0;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- /* TBD (used by procfs) */
- return 0;
-diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h
-index 0c3550c82b726..252ed38ce8c5a 100644
---- a/arch/mips/include/asm/processor.h
-+++ b/arch/mips/include/asm/processor.h
-@@ -369,7 +369,7 @@ static inline void flush_thread(void)
- {
- }
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
- THREAD_SIZE - 32 - sizeof(struct pt_regs))
-diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
-index 95aa86fa60778..cbff1b974f882 100644
---- a/arch/mips/kernel/process.c
-+++ b/arch/mips/kernel/process.c
-@@ -511,7 +511,7 @@ static int __init frame_info_init(void)
-
- /*
- * Without schedule() frame info, result given by
-- * thread_saved_pc() and get_wchan() are not reliable.
-+ * thread_saved_pc() and __get_wchan() are not reliable.
- */
- if (schedule_mfi.pc_offset < 0)
- printk("Can't analyze schedule() prologue at %p\n", schedule);
-@@ -652,9 +652,9 @@ unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
- #endif
-
- /*
-- * get_wchan - a maintenance nightmare^W^Wpain in the ass ...
-+ * __get_wchan - a maintenance nightmare^W^Wpain in the ass ...
- */
--unsigned long get_wchan(struct task_struct *task)
-+unsigned long __get_wchan(struct task_struct *task)
- {
- unsigned long pc = 0;
- #ifdef CONFIG_KALLSYMS
-@@ -662,8 +662,6 @@ unsigned long get_wchan(struct task_struct *task)
- unsigned long ra = 0;
- #endif
-
-- if (!task || task == current || task_is_running(task))
-- goto out;
- if (!task_stack_page(task))
- goto out;
-
-diff --git a/arch/nds32/include/asm/processor.h b/arch/nds32/include/asm/processor.h
-index b82369c7659d4..e6bfc74972bb3 100644
---- a/arch/nds32/include/asm/processor.h
-+++ b/arch/nds32/include/asm/processor.h
-@@ -83,7 +83,7 @@ extern struct task_struct *last_task_used_math;
- /* Prepare to copy thread state - unlazy all lazy status */
- #define prepare_to_copy(tsk) do { } while (0)
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define cpu_relax() barrier()
-
-diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c
-index 391895b54d13c..49fab9e39cbff 100644
---- a/arch/nds32/kernel/process.c
-+++ b/arch/nds32/kernel/process.c
-@@ -233,15 +233,12 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpu)
-
- EXPORT_SYMBOL(dump_fpu);
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long fp, lr;
- unsigned long stack_start, stack_end;
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- if (IS_ENABLED(CONFIG_FRAME_POINTER)) {
- stack_start = (unsigned long)end_of_stack(p);
- stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE;
-@@ -258,5 +255,3 @@ unsigned long get_wchan(struct task_struct *p)
- }
- return 0;
- }
--
--EXPORT_SYMBOL(get_wchan);
-diff --git a/arch/nios2/include/asm/processor.h b/arch/nios2/include/asm/processor.h
-index 94bcb86f679f5..b8125dfbcad2d 100644
---- a/arch/nios2/include/asm/processor.h
-+++ b/arch/nios2/include/asm/processor.h
-@@ -69,7 +69,7 @@ static inline void release_thread(struct task_struct *dead_task)
- {
- }
-
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
- #define task_pt_regs(p) \
- ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
-diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c
-index 9ff37ba2bb603..f8ea522a15880 100644
---- a/arch/nios2/kernel/process.c
-+++ b/arch/nios2/kernel/process.c
-@@ -217,15 +217,12 @@ void dump(struct pt_regs *fp)
- pr_emerg("\n\n");
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long fp, pc;
- unsigned long stack_page;
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- stack_page = (unsigned long)p;
- fp = ((struct switch_stack *)p->thread.ksp)->fp; /* ;dgt2 */
- do {
-diff --git a/arch/openrisc/include/asm/processor.h b/arch/openrisc/include/asm/processor.h
-index ad53b31848859..aa1699c18add8 100644
---- a/arch/openrisc/include/asm/processor.h
-+++ b/arch/openrisc/include/asm/processor.h
-@@ -73,7 +73,7 @@ struct thread_struct {
-
- void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
- void release_thread(struct task_struct *);
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define cpu_relax() barrier()
-
-diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
-index b0698d9ce14fa..3c0c91bcdcbaa 100644
---- a/arch/openrisc/kernel/process.c
-+++ b/arch/openrisc/kernel/process.c
-@@ -263,7 +263,7 @@ void dump_elf_thread(elf_greg_t *dest, struct pt_regs* regs)
- dest[35] = 0;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- /* TODO */
-
-diff --git a/arch/parisc/include/asm/processor.h b/arch/parisc/include/asm/processor.h
-index eeb7da0642891..85a2dbfe52787 100644
---- a/arch/parisc/include/asm/processor.h
-+++ b/arch/parisc/include/asm/processor.h
-@@ -273,7 +273,7 @@ struct mm_struct;
- /* Free all resources held by a thread. */
- extern void release_thread(struct task_struct *);
-
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) ((tsk)->thread.regs.iaoq[0])
- #define KSTK_ESP(tsk) ((tsk)->thread.regs.gr[30])
-diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
-index 38ec4ae812396..4f562dee65a2c 100644
---- a/arch/parisc/kernel/process.c
-+++ b/arch/parisc/kernel/process.c
-@@ -240,15 +240,12 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
- }
-
- unsigned long
--get_wchan(struct task_struct *p)
-+__get_wchan(struct task_struct *p)
- {
- struct unwind_frame_info info;
- unsigned long ip;
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- /*
- * These bracket the sleeping functions..
- */
-diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
-index f348e564f7dd5..e39bd0ff69f3a 100644
---- a/arch/powerpc/include/asm/processor.h
-+++ b/arch/powerpc/include/asm/processor.h
-@@ -300,7 +300,7 @@ struct thread_struct {
-
- #define task_pt_regs(tsk) ((tsk)->thread.regs)
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) ((tsk)->thread.regs? (tsk)->thread.regs->nip: 0)
- #define KSTK_ESP(tsk) ((tsk)->thread.regs? (tsk)->thread.regs->gpr[1]: 0)
-diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
-index 50436b52c2133..406d7ee9e3220 100644
---- a/arch/powerpc/kernel/process.c
-+++ b/arch/powerpc/kernel/process.c
-@@ -2111,14 +2111,11 @@ int validate_sp(unsigned long sp, struct task_struct *p,
-
- EXPORT_SYMBOL(validate_sp);
-
--static unsigned long __get_wchan(struct task_struct *p)
-+static unsigned long ___get_wchan(struct task_struct *p)
- {
- unsigned long ip, sp;
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- sp = p->thread.ksp;
- if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
- return 0;
-@@ -2137,14 +2134,14 @@ static unsigned long __get_wchan(struct task_struct *p)
- return 0;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long ret;
-
- if (!try_get_task_stack(p))
- return 0;
-
-- ret = __get_wchan(p);
-+ ret = ___get_wchan(p);
-
- put_task_stack(p);
-
-diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
-index 46b492c78cbbf..0749924d9e552 100644
---- a/arch/riscv/include/asm/processor.h
-+++ b/arch/riscv/include/asm/processor.h
-@@ -66,7 +66,7 @@ static inline void release_thread(struct task_struct *dead_task)
- {
- }
-
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
-
- static inline void wait_for_interrupt(void)
-diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
-index 315db3d0229bf..0fcdc0233faca 100644
---- a/arch/riscv/kernel/stacktrace.c
-+++ b/arch/riscv/kernel/stacktrace.c
-@@ -128,16 +128,14 @@ static bool save_wchan(void *arg, unsigned long pc)
- return true;
- }
-
--unsigned long get_wchan(struct task_struct *task)
-+unsigned long __get_wchan(struct task_struct *task)
- {
- unsigned long pc = 0;
-
-- if (likely(task && task != current && !task_is_running(task))) {
-- if (!try_get_task_stack(task))
-- return 0;
-- walk_stackframe(task, NULL, save_wchan, &pc);
-- put_task_stack(task);
-- }
-+ if (!try_get_task_stack(task))
-+ return 0;
-+ walk_stackframe(task, NULL, save_wchan, &pc);
-+ put_task_stack(task);
- return pc;
- }
-
-diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
-index 879b8e3f609cd..f54c152bf2bf9 100644
---- a/arch/s390/include/asm/processor.h
-+++ b/arch/s390/include/asm/processor.h
-@@ -192,7 +192,7 @@ static inline void release_thread(struct task_struct *tsk) { }
- void guarded_storage_release(struct task_struct *tsk);
- void gs_load_bc_cb(struct pt_regs *regs);
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
- #define task_pt_regs(tsk) ((struct pt_regs *) \
- (task_stack_page(tsk) + THREAD_SIZE) - 1)
- #define KSTK_EIP(tsk) (task_pt_regs(tsk)->psw.addr)
-diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
-index 350e94d0cac23..e5dd46b1bff8c 100644
---- a/arch/s390/kernel/process.c
-+++ b/arch/s390/kernel/process.c
-@@ -181,12 +181,12 @@ void execve_tail(void)
- asm volatile("sfpc %0" : : "d" (0));
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- struct unwind_state state;
- unsigned long ip = 0;
-
-- if (!p || p == current || task_is_running(p) || !task_stack_page(p))
-+ if (!task_stack_page(p))
- return 0;
-
- if (!try_get_task_stack(p))
-diff --git a/arch/sh/include/asm/processor_32.h b/arch/sh/include/asm/processor_32.h
-index aa92cc933889d..45240ec6b85a4 100644
---- a/arch/sh/include/asm/processor_32.h
-+++ b/arch/sh/include/asm/processor_32.h
-@@ -180,7 +180,7 @@ static inline void show_code(struct pt_regs *regs)
- }
- #endif
-
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
- #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[15])
-diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
-index 717de05c81f49..1c28e3cddb60d 100644
---- a/arch/sh/kernel/process_32.c
-+++ b/arch/sh/kernel/process_32.c
-@@ -182,13 +182,10 @@ __switch_to(struct task_struct *prev, struct task_struct *next)
- return prev;
- }
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long pc;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- /*
- * The same comment as on the Alpha applies here, too ...
- */
-diff --git a/arch/sparc/include/asm/processor_32.h b/arch/sparc/include/asm/processor_32.h
-index b6242f7771e9e..647bf0ac7beb9 100644
---- a/arch/sparc/include/asm/processor_32.h
-+++ b/arch/sparc/include/asm/processor_32.h
-@@ -89,7 +89,7 @@ static inline void start_thread(struct pt_regs * regs, unsigned long pc,
- /* Free all resources held by a thread. */
- #define release_thread(tsk) do { } while(0)
-
--unsigned long get_wchan(struct task_struct *);
-+unsigned long __get_wchan(struct task_struct *);
-
- #define task_pt_regs(tsk) ((tsk)->thread.kregs)
- #define KSTK_EIP(tsk) ((tsk)->thread.kregs->pc)
-diff --git a/arch/sparc/include/asm/processor_64.h b/arch/sparc/include/asm/processor_64.h
-index 5cf145f18f36b..ae851e8fce4c9 100644
---- a/arch/sparc/include/asm/processor_64.h
-+++ b/arch/sparc/include/asm/processor_64.h
-@@ -183,7 +183,7 @@ do { \
- /* Free all resources held by a thread. */
- #define release_thread(tsk) do { } while (0)
-
--unsigned long get_wchan(struct task_struct *task);
-+unsigned long __get_wchan(struct task_struct *task);
-
- #define task_pt_regs(tsk) (task_thread_info(tsk)->kregs)
- #define KSTK_EIP(tsk) (task_pt_regs(tsk)->tpc)
-diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
-index bbbe0cfef7465..2dc0bf9fe62eb 100644
---- a/arch/sparc/kernel/process_32.c
-+++ b/arch/sparc/kernel/process_32.c
-@@ -365,7 +365,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
- return 0;
- }
-
--unsigned long get_wchan(struct task_struct *task)
-+unsigned long __get_wchan(struct task_struct *task)
- {
- unsigned long pc, fp, bias = 0;
- unsigned long task_base = (unsigned long) task;
-@@ -373,9 +373,6 @@ unsigned long get_wchan(struct task_struct *task)
- struct reg_window32 *rw;
- int count = 0;
-
-- if (!task || task == current || task_is_running(task))
-- goto out;
--
- fp = task_thread_info(task)->ksp + bias;
- do {
- /* Bogus frame pointer? */
-diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
-index d1cc410d2f647..f5b2cac8669f9 100644
---- a/arch/sparc/kernel/process_64.c
-+++ b/arch/sparc/kernel/process_64.c
-@@ -663,7 +663,7 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
- return 0;
- }
-
--unsigned long get_wchan(struct task_struct *task)
-+unsigned long __get_wchan(struct task_struct *task)
- {
- unsigned long pc, fp, bias = 0;
- struct thread_info *tp;
-@@ -671,9 +671,6 @@ unsigned long get_wchan(struct task_struct *task)
- unsigned long ret = 0;
- int count = 0;
-
-- if (!task || task == current || task_is_running(task))
-- goto out;
--
- tp = task_thread_info(task);
- bias = STACK_BIAS;
- fp = task_thread_info(task)->ksp + bias;
-diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h
-index b5cf0ed116d9e..579692a40a556 100644
---- a/arch/um/include/asm/processor-generic.h
-+++ b/arch/um/include/asm/processor-generic.h
-@@ -106,6 +106,6 @@ extern struct cpuinfo_um boot_cpu_data;
- #define cache_line_size() (boot_cpu_data.cache_alignment)
-
- #define KSTK_REG(tsk, reg) get_thread_reg(reg, &tsk->thread.switch_buf)
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
- #endif
-diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
-index 457a38db368b7..82107373ac7e9 100644
---- a/arch/um/kernel/process.c
-+++ b/arch/um/kernel/process.c
-@@ -364,14 +364,11 @@ unsigned long arch_align_stack(unsigned long sp)
- }
- #endif
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long stack_page, sp, ip;
- bool seen_sched = 0;
-
-- if ((p == NULL) || (p == current) || task_is_running(p))
-- return 0;
--
- stack_page = (unsigned long) task_stack_page(p);
- /* Bail if the process has no kernel stack for some reason */
- if (stack_page == 0)
-diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
-index 577f342dbfb27..2b5f6c6c2b322 100644
---- a/arch/x86/include/asm/processor.h
-+++ b/arch/x86/include/asm/processor.h
-@@ -590,7 +590,7 @@ static inline void load_sp0(unsigned long sp0)
- /* Free all resources held by a thread. */
- extern void release_thread(struct task_struct *);
-
--unsigned long get_wchan(struct task_struct *p);
-+unsigned long __get_wchan(struct task_struct *p);
-
- /*
- * Generic CPUID function
-diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
-index cd426c3283ee1..266962547b58c 100644
---- a/arch/x86/kernel/process.c
-+++ b/arch/x86/kernel/process.c
-@@ -943,13 +943,10 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
- * because the task might wake up and we might look at a stack
- * changing under us.
- */
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long entry = 0;
-
-- if (p == current || task_is_running(p))
-- return 0;
--
- stack_trace_save_tsk(p, &entry, 1, 0);
- return entry;
- }
-diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h
-index 7f63aca6a0d34..ad15fbc572838 100644
---- a/arch/xtensa/include/asm/processor.h
-+++ b/arch/xtensa/include/asm/processor.h
-@@ -215,7 +215,7 @@ struct mm_struct;
- /* Free all resources held by a thread. */
- #define release_thread(thread) do { } while(0)
-
--extern unsigned long get_wchan(struct task_struct *p);
-+extern unsigned long __get_wchan(struct task_struct *p);
-
- #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
- #define KSTK_ESP(tsk) (task_pt_regs(tsk)->areg[1])
-diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
-index 0601653406123..47f933fed8700 100644
---- a/arch/xtensa/kernel/process.c
-+++ b/arch/xtensa/kernel/process.c
-@@ -298,15 +298,12 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
- * These bracket the sleeping functions..
- */
-
--unsigned long get_wchan(struct task_struct *p)
-+unsigned long __get_wchan(struct task_struct *p)
- {
- unsigned long sp, pc;
- unsigned long stack_page = (unsigned long) task_stack_page(p);
- int count = 0;
-
-- if (!p || p == current || task_is_running(p))
-- return 0;
--
- sp = p->thread.sp;
- pc = MAKE_PC_FROM_RA(p->thread.ra, p->thread.sp);
-
-diff --git a/include/linux/sched.h b/include/linux/sched.h
-index c1a927ddec646..71b012a224e4c 100644
---- a/include/linux/sched.h
-+++ b/include/linux/sched.h
-@@ -2137,6 +2137,7 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
- #endif /* CONFIG_SMP */
-
- extern bool sched_task_on_rq(struct task_struct *p);
-+extern unsigned long get_wchan(struct task_struct *p);
-
- /*
- * In order to reduce various lock holder preemption latencies provide an
-diff --git a/kernel/sched/core.c b/kernel/sched/core.c
-index aea60eae21a7f..d37f959ed1ab8 100644
---- a/kernel/sched/core.c
-+++ b/kernel/sched/core.c
-@@ -1962,6 +1962,25 @@ bool sched_task_on_rq(struct task_struct *p)
- return task_on_rq_queued(p);
- }
-
-+unsigned long get_wchan(struct task_struct *p)
-+{
-+ unsigned long ip = 0;
-+ unsigned int state;
-+
-+ if (!p || p == current)
-+ return 0;
-+
-+ /* Only get wchan if task is blocked and we can keep it that way. */
-+ raw_spin_lock_irq(&p->pi_lock);
-+ state = READ_ONCE(p->__state);
-+ smp_rmb(); /* see try_to_wake_up() */
-+ if (state != TASK_RUNNING && state != TASK_WAKING && !p->on_rq)
-+ ip = __get_wchan(p);
-+ raw_spin_unlock_irq(&p->pi_lock);
-+
-+ return ip;
-+}
-+
- static inline void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
- {
- if (!(flags & ENQUEUE_NOCLOCK))
---
-2.33.0
-
projects / thirdparty / kernel / stable-queue.git / commitdiff
