Hi,
There seems a deadloop(?) when mkfs.xfs -o rtdev.
# mkfs.xfs -r rtdev=/dev/disk/by-id/ata-MZ7KM1T6HAJM00D3_S2CXNAAH600026 /dev/d
isk/by-id/scsi-SHITACHI_HUSMH842_CLAR100_0LX0JWVA -f
meta-data=/dev/disk/by-id/scsi-SHITACHI_HUSMH842_CLAR100_0LX0JWVA isize=512 agcount=20, agsize=1221072 blks
= sectsz=4096 attr=2, projid32bit=1
= crc=1 finobt=1, sparse=1, rmapbt=0
= reflink=0 bigtime=1 inobtcount=1 nrext64=1
= exchange=0
data = bsize=4096 blocks=24421440, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0, ftype=1, parent=0
log =internal log bsize=4096 blocks=41799, version=2
= sectsz=4096 sunit=1 blks, lazy-count=1
realtime =/dev/disk/by-id/ata-MZ7KM1T6HAJM00D3_S2CXNAAH600026 extsz=4096 blocks=390703446, rtextents=390703446
Discarding blocks...Done.
Discarding blocks...Done.
It did not fishish after 10 mins.
# pstack 5785
#0 0x00007f8df5efc01a in pread64 () from /lib64/libc.so.6
#1 0x0000557b7bbfe9c3 in __read_buf.constprop.0 ()
#2 0x0000557b7bbc3030 in libxfs_buf_read_map ()
#3 0x0000557b7bbfe1ae in libxfs_trans_read_buf_map.constprop ()
#4 0x0000557b7bbee7ef in xfs_rtbuf_get ()
#5 0x0000557b7bbf03d8 in libxfs_rtfree_extent ()
#6 0x0000557b7bbbb322 in parseproto.lto_priv ()
#7 0x0000557b7bbb7643 in main ()
And,
1) more chance happen when kernel 6.12.36, but yet not happen when kernel 6.6.93.
2) it happen on both xfsprogs-6.11.0 and xfsprogs-6.4.
Best Regards
Wang Yugui (wangyugui@xxxxxxxxxxxx)
2025/07/17
