[f2fs-dev] F2FS Superblock Locations
Hello, Recently I was checking the file format for F2FS and noticed that the superblocks' location on the partition was both at the beginning. This means that if a large portion of the partition is corrupted, then it is possible for both superblocks to be destroyed. From my understanding of other filesystems, they prevent that by spreading out the superbolock backups across the partition so that it reduces the chances of all superblocks being destroyed. Has this been noticed before or am I mistaken in some way? Thank you, Zachary Winnerman -- Android is increasing in popularity, but the open development platform that developers love is also attractive to malware creators. Download this white paper to learn more about secure code signing practices that can help keep Android apps secure. http://pubads.g.doubleclick.net/gampad/clk?id=65839951iu=/4140/ostg.clktrk___ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
Re: [f2fs-dev] F2FS Superblock Locations
Hi, 2013-10-30 (수), 21:06 -0400, Zachary: Hello, Recently I was checking the file format for F2FS and noticed that the superblocks' location on the partition was both at the beginning. This means that if a large portion of the partition is corrupted, then it is possible for both superblocks to be destroyed. From my understanding of other filesystems, they prevent that by spreading out the superbolock backups across the partition so that it reduces the chances of all superblocks being destroyed. Has this been noticed before or am I mistaken in some way? IMHO, traditional rotational disks like HDDs need such the superblock backups. But for the solid-state disks like SSDs and eMMCs, I suspect that the backups are needed in practical, since its firmware, FTL, spreads the data across the whole NAND arrays to avoid cell errors (e.g., wear-out). So I think the superblock is very much hard to be broken especially on flash storages. Thank you, -- Jaegeuk Kim Samsung -- Android is increasing in popularity, but the open development platform that developers love is also attractive to malware creators. Download this white paper to learn more about secure code signing practices that can help keep Android apps secure. http://pubads.g.doubleclick.net/gampad/clk?id=65839951iu=/4140/ostg.clktrk ___ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
Re: [f2fs-dev] F2FS Superblock Locations
2013-10-30 (수), 23:33 -0400, Zachary: This was in reference to software mistakes that might wipe portions of the disk rather than hardware failures, it came up after I almost had one though it turns out its an unrelated problem. If this is due to the SW mistakes, it would be better to rewrite the superblock only by mkfs.f2fs, since the superblock contains just static information of its partition. I can simply add an option to do that in mkfs.f2fs. But, if the checkpoint is corrupted, there is no way to recover. Thanks, On Oct 30, 2013 9:56 PM, Jaegeuk Kim jaegeuk@samsung.com wrote: Hi, 2013-10-30 (수), 21:06 -0400, Zachary: Hello, Recently I was checking the file format for F2FS and noticed that the superblocks' location on the partition was both at the beginning. This means that if a large portion of the partition is corrupted, then it is possible for both superblocks to be destroyed. From my understanding of other filesystems, they prevent that by spreading out the superbolock backups across the partition so that it reduces the chances of all superblocks being destroyed. Has this been noticed before or am I mistaken in some way? IMHO, traditional rotational disks like HDDs need such the superblock backups. But for the solid-state disks like SSDs and eMMCs, I suspect that the backups are needed in practical, since its firmware, FTL, spreads the data across the whole NAND arrays to avoid cell errors (e.g., wear-out). So I think the superblock is very much hard to be broken especially on flash storages. Thank you, -- Jaegeuk Kim Samsung -- Jaegeuk Kim Samsung -- Android is increasing in popularity, but the open development platform that developers love is also attractive to malware creators. Download this white paper to learn more about secure code signing practices that can help keep Android apps secure. http://pubads.g.doubleclick.net/gampad/clk?id=65839951iu=/4140/ostg.clktrk ___ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
