Re: kern/54541: kernel panic using "zfs diff"

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

The following reply was made to PR kern/54541; it has been noted by GNATS.

From: Patrick Welche <prlw1%cam.ac.uk@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/54541: kernel panic using "zfs diff"
Date: Wed, 9 Oct 2019 16:12:50 +0100

 On Wed, Oct 09, 2019 at 02:30:02PM +0000, Patrick Welche wrote:
 >  zfs_onexit_fd_hold calls fd_getfile(133) which returns NULL. why?!
 
 (gdb) print fdp->fd_dt->dt_nfiles
 $6 = 20
 
 and 133 > 20
 
 
 better trace:
 (gdb) bt
 #0  fd_getfile (fd=133)
     at /usr/src/lib/librump/../../sys/rump/../kern/kern_descrip.c:365
 #1  0x00007f7ff4e6ab8d in zfs_onexit_fd_hold (fd=<optimized out>, 
     minorp=0x7f7fe2b3fbbc)
     at /usr/src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_onexit.c:145
 #2  0x00007f7ff4e6e2b9 in zfs_ioc_tmp_snapshot (zc=0x7f7ff481b000)
     at /usr/src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c:5252
 #3  0x00007f7ff4e765d2 in zfsdev_ioctl (dev=dev@entry=48640, 
     zcmd=zcmd@entry=3222821432, iarg=iarg@entry=140187241020992, 
     flag=flag@entry=3, cr=<optimized out>, rvalp=rvalp@entry=0x7f7fe2b3fcac)
     at /usr/src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c:6592
 #4  0x00007f7ff4e769e7 in nb_zfsdev_ioctl (dev=48640, cmd=3222821432, 
     argp=0x7f7fe2b3fe40, flag=3, l=<optimized out>)
     at /usr/src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c:7058
 #5  0x00007f7ff745f807 in VOP_IOCTL (vp=0x7f7ff72c16f0, 
     command=<optimized out>, data=<optimized out>, fflag=<optimized out>, 
     cred=<optimized out>)
     at /usr/src/lib/librump/../../sys/rump/../kern/vnode_if.c:610
 #6  0x00007f7ff7030285 in vn_ioctl (fp=0x7f7ff6bcc440, com=3222821432, 
     data=0x7f7fe2b3fe40)
     at /usr/src/lib/librumpvfs/../../sys/rump/../kern/vfs_vnops.c:775
 #7  0x00007f7ff744e593 in sys_ioctl (l=<optimized out>, uap=0x7f7ff6b3bf80, 
     retval=<optimized out>)
     at /usr/src/lib/librump/../../sys/rump/../kern/sys_generic.c:671
 #8  0x00007f7ff7801319 in sy_call (rval=0x7f7fe2b3ff10, uap=0x7f7ff6b3bf80, 
     l=0x7f7ff6a361c0, sy=0x7f7ff76f98d0 <rumpns_sysent+1296>)
     at /usr/src/sys/rump/kern/lib/libsysproxy/../../../../sys/syscallvar.h:65
 #9  sy_invoke (code=54, rval=0x7f7fe2b3ff10, uap=0x7f7ff6b3bf80, 
     l=0x7f7ff6a361c0, sy=0x7f7ff76f98d0 <rumpns_sysent+1296>)
     at /usr/src/sys/rump/kern/lib/libsysproxy/../../../../sys/syscallvar.h:94
 #10 hyp_syscall (num=54, arg=0x7f7ff6b3bf80, retval=0x7f7fe2b3ff90)
     at /usr/src/sys/rump/kern/lib/libsysproxy/sysproxy.c:74
 #11 0x00007f7ff6c06bd0 in rumpsyscall (regrv=0x7f7fe2b3ff80, 
     data=0x7f7ff6b3bf80, sysnum=54)
     at /usr/src/lib/librumpuser/rumpuser_sp.c:267
 #12 serv_handlesyscall (rhdr=0x7f7ff4806b48, rhdr=0x7f7ff4806b48, 
     data=0x7f7ff6b3bf80 "\003", spc=0x7f7ff6e0b7e8)
     at /usr/src/lib/librumpuser/rumpuser_sp.c:690
 #13 serv_workbouncer (arg=<optimized out>)
     at /usr/src/lib/librumpuser/rumpuser_sp.c:773
 #14 0x00007f7ff680c1e8 in pthread__create_tramp (cookie=0x7f7ff6b62c00)
     at /usr/src/lib/libpthread/pthread.c:593
 #15 0x00007f7ff60901c0 in ?? () from /usr/lib/libc.so.12
 #16 0x0000000000000000 in ?? ()