On Fri, Oct 30, 2015 at 09:43:28AM +0800, Tom Yan wrote: > So I noticed that SSD detection does work on unpartitioned devices in > mkfs.btrfs somehow: > https://bugzilla.kernel.org/show_bug.cgi?id=102921 > > Later I found out that it breaks at blkid_devno_to_wholedisk() in is_ssd(): > http://git.kernel.org/cgit/linux/kernel/git/kdave/btrfs-progs.git/tree/mkfs.c?h=v4.2.3#n1103 > > which Elliot had shown an example with strace: > https://lists.01.org/pipermail/linux-nvdimm/2015-September/002109.html > > And I think the problem occurs in the sysfs_get_devname() here: > https://git.kernel.org/cgit/utils/util-linux/util-linux.git/tree/lib/sysfs.c?h=v2.27#n785 > > Since sysfs_get_devname() has to call sysfs_readlink() later, which > output a long full device path in /sys, I don't think we should call > it directly with the buffer "diskname", which people won't expect that > it has to be large enough to carry the path in the middle of the > process. For example in is_sdd(), a char array of size 32 is used > ("wholedisk"). You're right. The function sysfs_get_devname() is not too elegant as it uses devname buffer for readlink. Fixed, the bugfix will be in v2.27.1. Thanks! Karel -- Karel Zak <kzak@xxxxxxxxxx> http://karelzak.blogspot.com -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
