Re: kern/56931: Panic in vfs_insmntque(): panic: TAILQ_* forw 0xffffec0928771d00 /usr/src/sys/kern/vfs_mount.c:487

[Jason Thorpe <thorpej%me.com@localhost>]

> On Jul 17, 2022, at 2:55 PM, Leonardo Taccari <leot%NetBSD.org@localhost> wrote:
> 
> I was able to reproduce that again when building www/webkit-gtk and at
> least in that case I think it was while doing a `make clean' (at least
> that was the last line I was able to read from an SSH session after it
> get stuck and dropped to ddb(4)), the bt seems the same:
> 
>  panic: TAILQ_* forw 0xffff98a871b71d00 /usr/src/sys/kern/vfs_mount.c:487

It’s blowing up here:

                TAILQ_REMOVE(&vp->v_mount->mnt_vnodelist, vip, vi_mntvnodes);

…specifically in this sanity check:

#define QUEUEDEBUG_TAILQ_OP(elm, field)                                 \
        if ((elm)->field.tqe_next &&                                    \
            (elm)->field.tqe_next->field.tqe_prev !=                    \
            &(elm)->field.tqe_next)                                     \
                QUEUEDEBUG_ABORT("TAILQ_* forw %p %s:%d", (elm),        \
                    __FILE__, __LINE__);                                \
        if (*(elm)->field.tqe_prev != (elm))                            \
                QUEUEDEBUG_ABORT("TAILQ_* back %p %s:%d", (elm),        \
                    __FILE__, __LINE__);

From your core dump, can you print out the values of those pointers?

-- thorpej