From efbed4dc5857f845d787e406ce85097d1ccc5c4f Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Thu, 17 Oct 2013 21:11:01 -0400 Subject: [PATCH] ext4: add ratelimiting to ext4 messages In the case of a storage device that suddenly disappears, or in the case of significant file system corruption, this can result in a huge flood of messages being sent to the console. This can overflow the file system containing /var/log/messages, or if a serial console is configured, this can slow down the system so much that a hardware watchdog can end up triggering forcing a system reboot. Google-Bug-Id: 7258357 Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 6 ++ fs/ext4/super.c | 152 ++++++++++++++++++++++++++++++------------------ 2 files changed, 100 insertions(+), 58 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index af815ea9d7cc..65485ab7a889 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -29,6 +29,7 @@ #include #include #include +#include #include #ifdef __KERNEL__ #include @@ -1314,6 +1315,11 @@ struct ext4_sb_info { unsigned long s_es_last_sorted; struct percpu_counter s_extent_cache_cnt; spinlock_t s_es_lru_lock ____cacheline_aligned_in_smp; + + /* Ratelimit ext4 messages. */ + struct ratelimit_state s_err_ratelimit_state; + struct ratelimit_state s_warning_ratelimit_state; + struct ratelimit_state s_msg_ratelimit_state; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 2c2e6cbc6bed..d3a857bfae47 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -411,20 +411,26 @@ static void ext4_handle_error(struct super_block *sb) sb->s_id); } +#define ext4_error_ratelimit(sb) \ + ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state), \ + "EXT4-fs error") + void __ext4_error(struct super_block *sb, const char *function, unsigned int line, const char *fmt, ...) { struct va_format vaf; va_list args; - va_start(args, fmt); - vaf.fmt = fmt; - vaf.va = &args; - printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n", - sb->s_id, function, line, current->comm, &vaf); - va_end(args); + if (ext4_error_ratelimit(sb)) { + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + printk(KERN_CRIT + "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n", + sb->s_id, function, line, current->comm, &vaf); + va_end(args); + } save_error_info(sb, function, line); - ext4_handle_error(sb); } @@ -438,22 +444,23 @@ void __ext4_error_inode(struct inode *inode, const char *function, es->s_last_error_ino = cpu_to_le32(inode->i_ino); es->s_last_error_block = cpu_to_le64(block); + if (ext4_error_ratelimit(inode->i_sb)) { + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + if (block) + printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: " + "inode #%lu: block %llu: comm %s: %pV\n", + inode->i_sb->s_id, function, line, inode->i_ino, + block, current->comm, &vaf); + else + printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: " + "inode #%lu: comm %s: %pV\n", + inode->i_sb->s_id, function, line, inode->i_ino, + current->comm, &vaf); + va_end(args); + } save_error_info(inode->i_sb, function, line); - va_start(args, fmt); - vaf.fmt = fmt; - vaf.va = &args; - if (block) - printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: " - "inode #%lu: block %llu: comm %s: %pV\n", - inode->i_sb->s_id, function, line, inode->i_ino, - block, current->comm, &vaf); - else - printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: " - "inode #%lu: comm %s: %pV\n", - inode->i_sb->s_id, function, line, inode->i_ino, - current->comm, &vaf); - va_end(args); - ext4_handle_error(inode->i_sb); } @@ -469,27 +476,28 @@ void __ext4_error_file(struct file *file, const char *function, es = EXT4_SB(inode->i_sb)->s_es; es->s_last_error_ino = cpu_to_le32(inode->i_ino); + if (ext4_error_ratelimit(inode->i_sb)) { + path = d_path(&(file->f_path), pathname, sizeof(pathname)); + if (IS_ERR(path)) + path = "(unknown)"; + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + if (block) + printk(KERN_CRIT + "EXT4-fs error (device %s): %s:%d: inode #%lu: " + "block %llu: comm %s: path %s: %pV\n", + inode->i_sb->s_id, function, line, inode->i_ino, + block, current->comm, path, &vaf); + else + printk(KERN_CRIT + "EXT4-fs error (device %s): %s:%d: inode #%lu: " + "comm %s: path %s: %pV\n", + inode->i_sb->s_id, function, line, inode->i_ino, + current->comm, path, &vaf); + va_end(args); + } save_error_info(inode->i_sb, function, line); - path = d_path(&(file->f_path), pathname, sizeof(pathname)); - if (IS_ERR(path)) - path = "(unknown)"; - va_start(args, fmt); - vaf.fmt = fmt; - vaf.va = &args; - if (block) - printk(KERN_CRIT - "EXT4-fs error (device %s): %s:%d: inode #%lu: " - "block %llu: comm %s: path %s: %pV\n", - inode->i_sb->s_id, function, line, inode->i_ino, - block, current->comm, path, &vaf); - else - printk(KERN_CRIT - "EXT4-fs error (device %s): %s:%d: inode #%lu: " - "comm %s: path %s: %pV\n", - inode->i_sb->s_id, function, line, inode->i_ino, - current->comm, path, &vaf); - va_end(args); - ext4_handle_error(inode->i_sb); } @@ -543,11 +551,13 @@ void __ext4_std_error(struct super_block *sb, const char *function, (sb->s_flags & MS_RDONLY)) return; - errstr = ext4_decode_error(sb, errno, nbuf); - printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n", - sb->s_id, function, line, errstr); - save_error_info(sb, function, line); + if (ext4_error_ratelimit(sb)) { + errstr = ext4_decode_error(sb, errno, nbuf); + printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n", + sb->s_id, function, line, errstr); + } + save_error_info(sb, function, line); ext4_handle_error(sb); } @@ -597,6 +607,9 @@ void __ext4_msg(struct super_block *sb, struct va_format vaf; va_list args; + if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs")) + return; + va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; @@ -610,6 +623,10 @@ void __ext4_warning(struct super_block *sb, const char *function, struct va_format vaf; va_list args; + if (!___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), + "EXT4-fs warning")) + return; + va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; @@ -633,18 +650,20 @@ __acquires(bitlock) es->s_last_error_block = cpu_to_le64(block); __save_error_info(sb, function, line); - va_start(args, fmt); - - vaf.fmt = fmt; - vaf.va = &args; - printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ", - sb->s_id, function, line, grp); - if (ino) - printk(KERN_CONT "inode %lu: ", ino); - if (block) - printk(KERN_CONT "block %llu:", (unsigned long long) block); - printk(KERN_CONT "%pV\n", &vaf); - va_end(args); + if (ext4_error_ratelimit(sb)) { + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ", + sb->s_id, function, line, grp); + if (ino) + printk(KERN_CONT "inode %lu: ", ino); + if (block) + printk(KERN_CONT "block %llu:", + (unsigned long long) block); + printk(KERN_CONT "%pV\n", &vaf); + va_end(args); + } if (test_opt(sb, ERRORS_CONT)) { ext4_commit_super(sb, 0); @@ -2606,6 +2625,12 @@ EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc); EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128); EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb); EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error); +EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); +EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst); +EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); +EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst); +EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval); +EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst); static struct attribute *ext4_attrs[] = { ATTR_LIST(delayed_allocation_blocks), @@ -2623,6 +2648,12 @@ static struct attribute *ext4_attrs[] = { ATTR_LIST(max_writeback_mb_bump), ATTR_LIST(extent_max_zeroout_kb), ATTR_LIST(trigger_fs_error), + ATTR_LIST(err_ratelimit_interval_ms), + ATTR_LIST(err_ratelimit_burst), + ATTR_LIST(warning_ratelimit_interval_ms), + ATTR_LIST(warning_ratelimit_burst), + ATTR_LIST(msg_ratelimit_interval_ms), + ATTR_LIST(msg_ratelimit_burst), NULL, }; @@ -4118,6 +4149,11 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) if (es->s_error_count) mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */ + /* Enable message ratelimiting. Default is 10 messages per 5 secs. */ + ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10); + ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10); + ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10); + kfree(orig_data); return 0; -- GitLab