Bug 224009 - Kernel panic after failed attempt to mount locked sdcard.
Summary: Kernel panic after failed attempt to mount locked sdcard.
Status: Closed DUPLICATE of bug 224037
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: 11.0-RELEASE
Hardware: amd64 Any
: --- Affects Many People
Assignee: freebsd-bugs (Nobody)
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-12-01 02:55 UTC by Peter C B Henderson
Modified: 2017-12-02 16:30 UTC (History)
1 user (show)

See Also:

Attachments
core.txt.1 (486.79 KB, text/plain)
2017-12-01 02:55 UTC, Peter C B Henderson 		no flags Details
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Description Peter C B Henderson 2017-12-01 02:55:25 UTC 
Created attachment 188444 [details]
core.txt.1

After using a locked sdcard, mounted ro, I unmounted it and inadvertently attempted to mount it rw.  There was a message to the effect that this wasn't allowed.  When I removed the sdcard, there was a kernel panic.

The sdcard reader is on my Dell monitor.

Output of uname -a:
FreeBSD hydrogen 11.0-RELEASE-p16 FreeBSD 11.0-RELEASE-p16 #0 r326382: Thu Nov 30 22:26:02 AEDT 2017     root@hydrogen:/usr/obj/usr/src/sys/GENERIC  amd64

Entries in fstab:
/dev/da1s1              /sdcard         msdosfs rw,noauto       0       0
/dev/da1s1              /sdcard-locked  msdosfs ro,noauto       0       0
Comment 1 Conrad Meyer freebsd_committer freebsd_triage 2017-12-01 03:19:32 UTC 
The interesting part of the panic (looks like NULL pointer dereference) is:

#5 0xffffffff80f84611 at calltrap+0x8
#6 0xffffffff80b8b227 at bufwrite+0x267
#7 0xffffffff80b9aac0 at vop_stdfsync+0x290
#8 0xffffffff80985fa6 at devfs_fsync+0x26
#9 0xffffffff8110cc8d at VOP_FSYNC_APV+0x8d
#10 0xffffffff80bb30ee at sched_sync+0x3be
#11 0xffffffff80a90485 at fork_exit+0x85
#12 0xffffffff80f84b4e at fork_trampoline+0xe
Comment 2 Conrad Meyer freebsd_committer freebsd_triage 2017-12-02 16:30:14 UTC 
Stack and probable cause matches PR 224037, but the newer one has more context so I'm marking this one the duplicate.

*** This bug has been marked as a duplicate of bug 224037 ***