From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> euler inclusion category: bugfix bugzilla: 9509, https://gitee.com/openeuler/kernel/issues/I4K61K CVE: NA Reference: https://lore.kernel.org/lkml/20181017044843.GD1068@jagdpanzerIV/T/ ------------------------------------------------- Make printk_safe_enter_irqsave()/etc macros available to the rest of the kernel. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Hongbo Yao <yaohongbo@huawei.com> Signed-off-by: Peng Wu <wupeng58@huawei.com> Reviewed-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Cheng Jian <cj.chengjian@huawei.com> Reviewed-by: Cheng Jian <cj.chengjian@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- include/linux/printk.h | 40 +++++++++++++++++++++++++++++++++++++ kernel/printk/internal.h | 37 ---------------------------------- kernel/printk/printk_safe.c | 6 ++++-- 3 files changed, 44 insertions(+), 39 deletions(-) diff --git a/include/linux/printk.h b/include/linux/printk.h index e6a8ee6db68e..7d787f91db92 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -161,6 +161,46 @@ static inline void printk_nmi_direct_enter(void) { } static inline void printk_nmi_direct_exit(void) { } #endif /* PRINTK_NMI */ +#ifdef CONFIG_PRINTK +extern void printk_safe_enter(void); +extern void printk_safe_exit(void); + +#define printk_safe_enter_irqsave(flags) \ + do { \ + local_irq_save(flags); \ + printk_safe_enter(); \ + } while (0) + +#define printk_safe_exit_irqrestore(flags) \ + do { \ + printk_safe_exit(); \ + local_irq_restore(flags); \ + } while (0) + +#define printk_safe_enter_irq() \ + do { \ + local_irq_disable(); \ + printk_safe_enter(); \ + } while (0) + +#define printk_safe_exit_irq() \ + do { \ + printk_safe_exit(); \ + local_irq_enable(); \ + } while (0) +#else +/* + * On !PRINTK builds we still export console output related locks + * and some functions (console_unlock()/tty/etc.), so printk-safe + * must preserve the existing local IRQ guarantees. + */ +#define printk_safe_enter_irqsave(flags) local_irq_save(flags) +#define printk_safe_exit_irqrestore(flags) local_irq_restore(flags) + +#define printk_safe_enter_irq() local_irq_disable() +#define printk_safe_exit_irq() local_irq_enable() +#endif + struct dev_printk_info; #ifdef CONFIG_PRINTK diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h index 3a8fd491758c..b1c155328b04 100644 --- a/kernel/printk/internal.h +++ b/kernel/printk/internal.h @@ -22,53 +22,16 @@ int vprintk_store(int facility, int level, __printf(1, 0) int vprintk_default(const char *fmt, va_list args); __printf(1, 0) int vprintk_deferred(const char *fmt, va_list args); __printf(1, 0) int vprintk_func(const char *fmt, va_list args); -void __printk_safe_enter(void); -void __printk_safe_exit(void); void printk_safe_init(void); bool printk_percpu_data_ready(void); -#define printk_safe_enter_irqsave(flags) \ - do { \ - local_irq_save(flags); \ - __printk_safe_enter(); \ - } while (0) - -#define printk_safe_exit_irqrestore(flags) \ - do { \ - __printk_safe_exit(); \ - local_irq_restore(flags); \ - } while (0) - -#define printk_safe_enter_irq() \ - do { \ - local_irq_disable(); \ - __printk_safe_enter(); \ - } while (0) - -#define printk_safe_exit_irq() \ - do { \ - __printk_safe_exit(); \ - local_irq_enable(); \ - } while (0) - void defer_console_output(void); #else __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; } -/* - * In !PRINTK builds we still export logbuf_lock spin_lock, console_sem - * semaphore and some of console functions (console_unlock()/etc.), so - * printk-safe must preserve the existing local IRQ guarantees. - */ -#define printk_safe_enter_irqsave(flags) local_irq_save(flags) -#define printk_safe_exit_irqrestore(flags) local_irq_restore(flags) - -#define printk_safe_enter_irq() local_irq_disable() -#define printk_safe_exit_irq() local_irq_enable() - static inline void printk_safe_init(void) { } static inline bool printk_percpu_data_ready(void) { return false; } #endif /* CONFIG_PRINTK */ diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c index 2e9e3ed7d63e..d03c36565e0d 100644 --- a/kernel/printk/printk_safe.c +++ b/kernel/printk/printk_safe.c @@ -356,16 +356,18 @@ static __printf(1, 0) int vprintk_safe(const char *fmt, va_list args) } /* Can be preempted by NMI. */ -void __printk_safe_enter(void) +void printk_safe_enter(void) { this_cpu_inc(printk_context); } +EXPORT_SYMBOL_GPL(printk_safe_enter); /* Can be preempted by NMI. */ -void __printk_safe_exit(void) +void printk_safe_exit(void) { this_cpu_dec(printk_context); } +EXPORT_SYMBOL_GPL(printk_safe_exit); __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { -- 2.20.1