| Message ID | 20210911090059.1876456-4-yebin10@huawei.com |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Fix some issues about mmp | expand |
On Sat 11-09-21 17:00:56, Ye Bin wrote: > As mmp and check_mmp is point to the same data, so there will never > detect conflict. > To solve this issue just compare to local data. > > Signed-off-by: Ye Bin <yebin10@huawei.com> Good spotting! Just one nit below. > --- > fs/ext4/mmp.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c > index c781b09a78c9..4433fe7e9e86 100644 > --- a/fs/ext4/mmp.c > +++ b/fs/ext4/mmp.c > @@ -154,6 +154,7 @@ static int kmmpd(void *data) > unsigned long last_update_time; > unsigned long last_check_time; > unsigned long diff; > + char nodename[64]; Perhaps define a constant for the length of nodename and use it here as well as in the declaration of mmp_struct->mmp_nodename? Honza
diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c index c781b09a78c9..4433fe7e9e86 100644 --- a/fs/ext4/mmp.c +++ b/fs/ext4/mmp.c @@ -154,6 +154,7 @@ static int kmmpd(void *data) unsigned long last_update_time; unsigned long last_check_time; unsigned long diff; + char nodename[64]; int retval = 0; mmp_block = le64_to_cpu(es->s_mmp_block); @@ -169,8 +170,8 @@ static int kmmpd(void *data) BUILD_BUG_ON(sizeof(mmp->mmp_bdevname) < BDEVNAME_SIZE); bdevname(bh->b_bdev, mmp->mmp_bdevname); - memcpy(mmp->mmp_nodename, init_utsname()->nodename, - sizeof(mmp->mmp_nodename)); + memcpy(nodename, init_utsname()->nodename, sizeof(nodename)); + memcpy(mmp->mmp_nodename, nodename, sizeof(mmp->mmp_nodename)); last_check_time = jiffies; while (!kthread_should_stop() && !sb_rdonly(sb)) { @@ -224,8 +225,8 @@ static int kmmpd(void *data) } mmp_check = (struct mmp_struct *)(bh_check->b_data); - if (mmp->mmp_seq != mmp_check->mmp_seq || - memcmp(mmp->mmp_nodename, mmp_check->mmp_nodename, + if (seq != mmp_check->mmp_seq || + memcmp(nodename, mmp_check->mmp_nodename, sizeof(mmp->mmp_nodename))) { dump_mmp_msg(sb, mmp_check, "Error while updating MMP info. "
As mmp and check_mmp is point to the same data, so there will never detect conflict. To solve this issue just compare to local data. Signed-off-by: Ye Bin <yebin10@huawei.com> --- fs/ext4/mmp.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)