Hi Yu, Thanks for your catch. Regards, Gu On 07/07/2014 09:39 AM, Chao Yu wrote: > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=75861 > > Denis 2014-05-10 11:28:59 UTC reported: > "F2FS-fs (mmcblk0p28): mounting.. > Unable to handle kernel NULL pointer dereference at virtual address 00000018 > ... > [<c0a2f678>] (_raw_spin_lock+0x3c/0x70) from [<c03a0330>] (issue_flush_thread+0x50/0x17c) > [<c03a0330>] (issue_flush_thread+0x50/0x17c) from [<c01b4064>] (kthread+0x98/0xa4) > [<c01b4064>] (kthread+0x98/0xa4) from [<c0108060>] (kernel_thread_exit+0x0/0x8)" > > This patch assign cmd_control_info in sm_info before issue_flush_thread is being > created, so this make sure that issue flush thread will have no chance to access > invalid info in fcc. > > Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx> Reviewed-by: Gu Zheng <guz.fnst@xxxxxxxxxxxxxx> > --- > fs/f2fs/segment.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index bb5980d..a4f8375 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -272,14 +272,15 @@ int create_flush_cmd_control(struct f2fs_sb_info *sbi) > return -ENOMEM; > spin_lock_init(&fcc->issue_lock); > init_waitqueue_head(&fcc->flush_wait_queue); > + sbi->sm_info->cmd_control_info = fcc; > fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi, > "f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev)); > if (IS_ERR(fcc->f2fs_issue_flush)) { > err = PTR_ERR(fcc->f2fs_issue_flush); > kfree(fcc); > + sbi->sm_info->cmd_control_info = NULL; > return err; > } > - sbi->sm_info->cmd_control_info = fcc; > > return err; > } -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
