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Description of problem: fdisk may suggest poor default values for the start of an extended (or primary) partition for a partition table made by an earlier version of fdisk or another program. Version-Release number of selected component (if applicable): 2.19.1-1.fc15 How reproducible: start with this partition table definition: # fdisk /dev/sda Command (m for help): p Disk /dev/sda: 64.0 GB, 64023257088 bytes 255 heads, 63 sectors/track, 7783 cylinders, total 125045424 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000a3918 Device Boot Start End Blocks Id System /dev/sda1 * 63 524350 262144 83 Linux /dev/sda2 524351 17301566 8388608 83 Linux /dev/sda3 17303552 17827839 262144 83 Linux # In other words, start with a partially completed partition table missing one or more primary or its extended partition, created by an earlier version of fdisk or another program. Add a primary or extended partition, accepting the default values suggested. For example, Steps to Reproduce: 1. fdisk /dev/sda 2. n 3. e 4. Selected partition 4 First sector (17301567-125045423, default 17301567): Using default value 17301567 5. Last sector, +sectors or +size{K,M,G} (17301567-17303551, default 17303551): Using default value 17303551 Actual results: Command (m for help): p Disk /dev/sda: 64.0 GB, 64023257088 bytes 255 heads, 63 sectors/track, 7783 cylinders, total 125045424 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000a3918 Device Boot Start End Blocks Id System /dev/sda1 * 63 524350 262144 83 Linux /dev/sda2 524351 17301566 8388608 83 Linux /dev/sda3 17303552 17827839 262144 83 Linux /dev/sda4 17301567 17303551 992+ 5 Extended Expected results: An extended partition spanning from the end of partition 3 to the end of the disk. A 992 sector = 496 KB extended partition between partition 2 and partition 3 should not be suggested, since it would very rarely be useful for creating logical partitions. Additional info: One could say that the fdisk functions correctly and it is operator error to accept the useless extended partition default addresses it provides, but it should be clear that when the user creates an extended partition, it should use by the default the largest free area as opposed to the smallest free area, especially when that smallest free area is not even 1MB in size. Accepting the defaults also creates out of order partitions, which isn't necessarily bad, but isn't what the user or some programs might expect.
(In reply to comment #0) > One could say that the fdisk functions correctly and it is operator error to > accept the useless extended partition default addresses it provides, but it The fdisk command is simple and stupid, and it's expected ;-) > should be clear that when the user creates an extended partition, it should use > by the default the largest free area as opposed to the smallest free area, > especially when that smallest free area is not even 1MB in size. It uses the first free area without care about partition type. In the "First sector" dialog you can select the right place and skip useless gaps. Anyway, I have added a note about this issue to util-linux upstream TODO list. I think we can improve the dialog to make it more user friendly. We will see... Thanks.