511444 – sys-fs/zfs-kmod-0.6.2-r5 with sys-kernel/gentoo-sources-3.14.4 - upon reading /proc/spl/kstat/zfs/arcstats - BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 in [<ffffffffa04618ac>] __kstat_create+0x66c/0x690 [spl]

Bug 511444 - sys-fs/zfs-kmod-0.6.2-r5 with sys-kernel/gentoo-sources-3.14.4 - upon reading /proc/spl/kstat/zfs/arcstats - BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 in [<ffffffffa04618ac>] __kstat_create+0x66c/0x690 [spl]

Summary: sys-fs/zfs-kmod-0.6.2-r5 with sys-kernel/gentoo-sources-3.14.4 - upon reading...

Status:	RESOLVED INVALID

Alias:	None

Product:	Gentoo Linux
Classification:	Unclassified
Component:	[OLD] Core system (show other bugs)
Hardware:	All Linux

Importance:	Normal normal (vote)
Assignee:	Richard Yao (RETIRED)

URL:
Whiteboard:
Keywords:

Depends on:
Blocks:

Reported:	2014-05-25 12:06 UTC by Matthias Maier
Modified:	2014-05-25 21:34 UTC (History)
CC List:	0 users

See Also:
Package list:
Runtime testing required:	---

Attachments
Full dmesg output with kernel oops (dmesg,76.89 KB, text/plain) 2014-05-25 12:07 UTC, Matthias Maier	Details
emerge --info (emerge-info,5.43 KB, text/plain) 2014-05-25 12:07 UTC, Matthias Maier	Details
kernel configuration (kernel-config-x86_64-3.14.4-gentoo,92.25 KB, text/plain) 2014-05-25 12:09 UTC, Matthias Maier	Details
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.

Description Matthias Maier gentoo-dev

2014-05-25 12:06:05 UTC

With sys-fs/zfs-kmod-0.6.2-r5 (sys-fs/zfs-0.6.2-r5, sys-kernel/spl-0.6.2-r5) I encounter a NULL pointer dereference and Kernel Oops upon reading /proc/spl/kstat/zfs/arcstats (see attached dmesg).

This happens with sys-kernel/gentoo-sources-3.14.4, the currently stable version sys-kernel/gentoo-sources-3.12.13 is fine.

I also encounter some strange memory leak problems - slowly declining MemFree and MemAvailable by constant memory consumption from userland, and kernel (slab, buffer, cache) that I suspect are related to this. So this might be an indicator for a bigger problem with memory management - or memory accounting (which changed a bit in 3.14, e.g. new MemAvailable).

emerge --info and kernel configuration attached.

Reproducible: Always

Comment 1 Matthias Maier gentoo-dev

2014-05-25 12:07:00 UTC

Created attachment 377610 [details]
Full dmesg output with kernel oops

Comment 2 Matthias Maier gentoo-dev

2014-05-25 12:07:46 UTC

Created attachment 377612 [details]
emerge --info

Comment 3 Matthias Maier gentoo-dev

2014-05-25 12:09:21 UTC

Created attachment 377614 [details]
kernel configuration

Comment 4 Matthias Maier gentoo-dev

2014-05-25 21:34:51 UTC

Well, I tried to investigate a bit and I could not reproduce on a test setup. Later, upon completely rebuilding everything the kernel oops (and the memory consumption problem) do not show up any more. So, this was very likely a layer 8 problem.

Sorry for the noise.