There are 2 scenarios which would trigger infinite loop: 1. None log is recorded, then dumplog with "-n", for example: debugfs -R "logdump -O -n 10" /dev/xxx while /dev/xxx has no valid log recorded. 2. The log area is full and cycle write is triggered, then dumplog with debugfs -R "logdump -aOS" /dev/xxx This patch add a new flag "reverse_flag" to mark if logdump has reached to tail of logarea, it is default false, and set in macro WRAP(). If reverse_flag is true, and we comes to first_transaction_blocknr again, just break the logdump loop. Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx> --- debugfs/logdump.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/debugfs/logdump.c b/debugfs/logdump.c index b600228e..05ea839a 100644 --- a/debugfs/logdump.c +++ b/debugfs/logdump.c @@ -52,6 +52,7 @@ static int64_t dump_counts; static blk64_t block_to_dump, bitmap_to_dump, inode_block_to_dump; static unsigned int group_to_dump, inode_offset_to_dump; static ext2_ino_t inode_to_dump; +static bool reverse_flag; struct journal_source { @@ -80,8 +81,10 @@ static void dump_fc_block(FILE *out_file, char *buf, int blocksize, static void do_hexdump (FILE *, char *, int); #define WRAP(jsb, blocknr, maxlen) \ - if (blocknr >= (maxlen)) \ - blocknr -= (maxlen - be32_to_cpu((jsb)->s_first)); + if (blocknr >= (maxlen)) { \ + blocknr -= (maxlen - be32_to_cpu((jsb)->s_first)); \ + reverse_flag = true; \ + } void do_logdump(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)), void *infop EXT2FS_ATTR((unused))) @@ -115,6 +118,7 @@ void do_logdump(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)), inode_block_to_dump = ANY_BLOCK; inode_to_dump = -1; dump_counts = -1; + reverse_flag = false; reset_getopt(); while ((c = getopt (argc, argv, "ab:ci:f:OsSn:")) != EOF) { @@ -477,8 +481,7 @@ static void dump_journal(char *cmdname, FILE *out_file, if (dump_old && (dump_counts != -1) && (cur_counts >= dump_counts)) break; - if ((blocknr == first_transaction_blocknr) && - (cur_counts != 0) && dump_old && (dump_counts != -1)) { + if ((blocknr == first_transaction_blocknr) && dump_old && reverse_flag) { fprintf(out_file, "Dump all %lld journal records.\n", (long long) cur_counts); break; -- 2.32.0