diff options
| author | Kees Cook <keescook@chromium.org> | 2021-09-29 15:02:14 -0700 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2021-10-15 11:25:14 +0200 |
| commit | 42a20f86dc19f9282d974df0ba4d226c865ab9dd (patch) | |
| tree | 548e09e31785a53f7907e0e4c28471d0e53fcbb5 /arch/um | |
| parent | bc9bbb81730ea667c31c5b284f95ee312bab466f (diff) | |
| download | linux-42a20f86dc19f9282d974df0ba4d226c865ab9dd.tar.gz | |
sched: Add wrapper for get_wchan() to keep task blocked
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
Diffstat (limited to 'arch/um')
| -rw-r--r-- | arch/um/include/asm/processor-generic.h | 2 | ||||
| -rw-r--r-- | arch/um/kernel/process.c | 5 |
2 files changed, 2 insertions, 5 deletions
diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h index b5cf0ed116d9..579692a40a55 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 457a38db368b..82107373ac7e 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) |