Hi all, > -----Original Message----- > From: He YunLei [mailto:heyun...@huawei.com] > Sent: Wednesday, December 09, 2015 3:15 PM > To: Chao Yu > Cc: 'Jaegeuk Kim'; linux-f2fs-devel@lists.sourceforge.net; hebi...@huawei.com; > stuart...@huawei.com > Subject: Re: [f2fs-dev] [PATCH] back-up raw_super in sbi > > On 2015/12/9 14:11, Chao Yu wrote: > > Hi, > > > >> -----Original Message----- > >> From: Jaegeuk Kim [mailto:jaeg...@kernel.org] > >> Sent: Wednesday, December 09, 2015 2:19 AM > >> To: Yunlei He > >> Cc: linux-f2fs-devel@lists.sourceforge.net; chao2...@samsung.com; > >> hebi...@huawei.com; > >> stuart...@huawei.com > >> Subject: Re: [f2fs-dev] [PATCH] back-up raw_super in sbi > >> > >> Hi Yunlei, > >> > >> On Tue, Dec 08, 2015 at 09:17:13PM +0800, Yunlei He wrote: > >>> write_checkpoint() tries to get cp_blkaddr from superblock buffer, > >>> if the buffer happen to be destroied by something else, it may > > > > Yunlei, > > > > You mean hacking in memory? could you share more about process of > > destroying? > > I do some test on kernel version 3.10 like this: > > with mounted f2fs partition, use dd to erase the first sb > > dd if=/dev/zero of=/dev/sdx bs=4k count=1 > > then sync, and the system will panic. > > the log added in function do_checkpoint show: > > heyunlei:start_blk = 0 > > So maybe dd dirty the super block buffer stored in sbi.
Ah, I can understand your concerns now, thanks for your explanation! :) > > But, in latest dev branch, it has no problem, I don't know why. I do the test with latest dev branch, it shows warning dmesg info as F2FS_CHECK_FS is off. I think it has problem actually. > >> Need to consider f2fs_commit_super and kfree() in put_super. > > > > How about releasing grabbed block buffer 'sbi->raw_super_buf' since we > > already had one copy of it? Hi Jaegeuk, Yunlei, Any thoughts? ------------------------------------------------------------------------------ _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
