The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 604407890ecf624c2fb41013c82b22aade59b455 Mon Sep 17 00:00:00 2001 From: Bart Van Assche <bart.vanassche@xxxxxxx> Date: Wed, 9 Aug 2017 11:32:11 -0700 Subject: [PATCH] dm: fix printk() rate limiting code Using the same rate limiting state for different kinds of messages is wrong because this can cause a high frequency message to suppress a report of a low frequency message. Hence use a unique rate limiting state per message type. Fixes: 71a16736a15e ("dm: use local printk ratelimit") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 8298670757e9..d669fddd9290 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -27,16 +27,6 @@ #define DM_MSG_PREFIX "core" -#ifdef CONFIG_PRINTK -/* - * ratelimit state to be used in DMXXX_LIMIT(). - */ -DEFINE_RATELIMIT_STATE(dm_ratelimit_state, - DEFAULT_RATELIMIT_INTERVAL, - DEFAULT_RATELIMIT_BURST); -EXPORT_SYMBOL(dm_ratelimit_state); -#endif - /* * Cookies are numeric values sent with CHANGE and REMOVE * uevents while resuming, removing or renaming the device. diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 1473455d0341..4f2b3b2076c4 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -549,46 +549,29 @@ void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); *---------------------------------------------------------------*/ #define DM_NAME "device-mapper" -#ifdef CONFIG_PRINTK -extern struct ratelimit_state dm_ratelimit_state; - -#define dm_ratelimit() __ratelimit(&dm_ratelimit_state) -#else -#define dm_ratelimit() 0 -#endif +#define DM_RATELIMIT(pr_func, fmt, ...) \ +do { \ + static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, \ + DEFAULT_RATELIMIT_BURST); \ + \ + if (__ratelimit(&rs)) \ + pr_func(DM_FMT(fmt), ##__VA_ARGS__); \ +} while (0) #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n" #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__) #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__) -#define DMERR_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMERR(fmt, ##__VA_ARGS__); \ -} while (0) - +#define DMERR_LIMIT(fmt, ...) DM_RATELIMIT(pr_err, fmt, ##__VA_ARGS__) #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__) -#define DMWARN_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMWARN(fmt, ##__VA_ARGS__); \ -} while (0) - +#define DMWARN_LIMIT(fmt, ...) DM_RATELIMIT(pr_warn, fmt, ##__VA_ARGS__) #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) -#define DMINFO_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMINFO(fmt, ##__VA_ARGS__); \ -} while (0) +#define DMINFO_LIMIT(fmt, ...) DM_RATELIMIT(pr_info, fmt, ##__VA_ARGS__) #ifdef CONFIG_DM_DEBUG #define DMDEBUG(fmt, ...) printk(KERN_DEBUG DM_FMT(fmt), ##__VA_ARGS__) -#define DMDEBUG_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMDEBUG(fmt, ##__VA_ARGS__); \ -} while (0) +#define DMDEBUG_LIMIT(fmt, ...) DM_RATELIMIT(pr_debug, fmt, ##__VA_ARGS__) #else #define DMDEBUG(fmt, ...) no_printk(fmt, ##__VA_ARGS__) #define DMDEBUG_LIMIT(fmt, ...) no_printk(fmt, ##__VA_ARGS__)