r323694 amd64 - crash in linsysfs: Was: svn commit: r323692 - in head/sys/compat: linsysfs linux

On Sunday 17 September 2017 23:40:16 Conrad Meyer wrote:
> Author: cem
> Date: Sun Sep 17 23:40:16 2017
> New Revision: 323692
> URL: https://svnweb.freebsd.org/changeset/base/323692
> 
> Log:
>   linsysfs(5): Add support for recent libdrm
> 
>   Expose more information about PCI devices (and GPUs in 
particular) via
>   linsysfs to libdrm.
> 
>   This allows unmodified modern 64-bit Linux libdrm to work, 
which allows
>   modern Linux Mesa to work.  The submitter reports that he 
tested the
> change with an Ubuntu 16.04 chroot + amdgpu from graphics/drm-
next-kmod.
> 
>   PR:		222375
>   Submitted by:	Greg V <greg AT unrelenting.technology>
> 
> Modified:
>   head/sys/compat/linsysfs/linsysfs.c
>   head/sys/compat/linux/linux_util.c
> 
> Modified: head/sys/compat/linsysfs/linsysfs.c
> 

 Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address   = 0x3f
fault code              = supervisor read data, page not present
instruction pointer     = 0x20:0xffffffff81027779
stack pointer           = 0x28:0xfffffe034bc66e70
frame pointer           = 0x28:0xfffffe034bc66f00
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 65 (mount)
trap number             = 12
panic: page fault
cpuid = 0
time = 1505752282
Uptime: 2s
...
#0  doadump (textdump=<value optimized out>) at pcpu.h:232
232     pcpu.h: No such file or directory.
        in pcpu.h
(kgdb) #0  doadump (textdump=<value optimized out>) at 
pcpu.h:232
#1  0xffffffff804d74f6 in kern_reboot (howto=260)
    at /usr/src/sys/kern/kern_shutdown.c:386
#2  0xffffffff804d791c in vpanic (fmt=<value optimized out>, 
    ap=<value optimized out>) at 
/usr/src/sys/kern/kern_shutdown.c:779
#3  0xffffffff804d7773 in panic (fmt=<value optimized out>)
    at /usr/src/sys/kern/kern_shutdown.c:710
#4  0xffffffff806bc877 in trap_fatal (frame=0xfffffe034bc66db0, 
eva=63)
    at /usr/src/sys/amd64/amd64/trap.c:799
#5  0xffffffff806bca59 in trap_pfault (frame=<value optimized 
out>, 
    usermode=<value optimized out>) at pcpu.h:247
#6  0xffffffff806bc1c3 in trap (frame=0xfffffe034bc66db0)
    at /usr/src/sys/amd64/amd64/trap.c:420
#7  0xffffffff806a2363 in calltrap ()
    at /usr/src/sys/amd64/amd64/exception.S:237
#8  0xffffffff81027779 in linsysfs_run_bus (dir=<value optimized 
out>)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:357
#9  0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff8000e028600)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#10 0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff8000e028600)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#11 0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff80004c8fe00)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#12 0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff80004c8fe00)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#13 0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff80004c8fe00)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#14 0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff80004c8fe00)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#15 0xffffffff810278a1 in linsysfs_run_bus 
(dir=0xfffff80004c8fe00)
    at /usr/src/sys/compat/linsysfs/linsysfs.c:382
#16 0xffffffff81027194 in linsysfs_init (pi=<value optimized 
out>, 
    vfc=<value optimized out>) at 
/usr/src/sys/compat/linsysfs/linsysfs.c:478
#17 0xffffffff80462773 in pfs_init (pi=0xffffffff810285e8, 
    vfc=0xffffffff810284e0) at 
/usr/src/sys/fs/pseudofs/pseudofs.c:395
#18 0xffffffff805792b0 in vfs_modevent (mod=<value optimized 
out>, 
    type=<value optimized out>, data=0xffffffff810284e0)
    at /usr/src/sys/kern/vfs_init.c:281
#19 0xffffffff804c09a8 in module_register_init 
(arg=0xffffffff810284c8)
    at /usr/src/sys/kern/kern_module.c:123
#20 0xffffffff804b5df6 in linker_load_module (kldname=<value 
optimized out>, 
    modname=0xfffff80004062a70 "linsysfs", parent=0x0, 
    verinfo=<value optimized out>, lfpp=<value optimized out>)
    at /usr/src/sys/kern/kern_linker.c:234
#21 0xffffffff804b731f in kern_kldload (td=<value optimized 
out>, 
    file=<value optimized out>, fileid=0xfffffe034bc677c4)
    at /usr/src/sys/kern/kern_linker.c:1042
#22 0xffffffff80578e1d in vfs_byname_kld (
    fstype=0xfffff80004062a70 "linsysfs", td=0xfffff80004c1f560, 
    error=0xfffffe034bc679ec) at 
/usr/src/sys/kern/vfs_init.c:147
#23 0xffffffff8057c44f in vfs_donmount (td=<value optimized 
out>, 
    fsflags=<value optimized out>, fsoptions=0xfffff80004ca2400)
    at /usr/src/sys/kern/vfs_mount.c:1088
#24 0xffffffff8057ba70 in sys_nmount (td=0xfffff80004c1f560, 
    uap=<value optimized out>) at 
/usr/src/sys/kern/vfs_mount.c:421
#25 0xffffffff806bd2a2 in amd64_syscall (td=0xfffff80004c1f560, 
traced=0)
    at subr_syscall.c:132
#26 0xffffffff806a26bb in Xfast_syscall ()
    at /usr/src/sys/amd64/amd64/exception.S:419
#27 0x0000000800a88b3a in ?? ()
Previous frame inner to this frame (corrupt stack?)