#1023725 rasdaemon: kernel null pointer dereference oops with rasdaemon

Package:
rasdaemon
Source:
rasdaemon
Description:
utility to receive RAS error tracings
Submitter:
Michael Stone
Date:
2026-08-11 04:09:02 UTC
Severity:
normal
Tags:
#1023725#5
Date:
2022-11-09 02:42:52 UTC
From:
To:
With linux-image-6.0.0-2-amd64 rasdaemon causes a kernel oops with a signature similar to this:
 BUG: kernel NULL pointer dereference, address: 00000000000001c8
 #PF: supervisor write access in kernel mode
 #PF: error_code(0x0002) - not-present page
 PGD 0 P4D 0
 Oops: 0002 [#1] PREEMPT SMP NOPTI
 CPU: 11 PID: 1227 Comm: rasdaemon Tainted: P           OE      6.0.0-2-amd64 #1  Debian 6.0.6-2
 RIP: 0010:ring_buffer_wake_waiters+0x1c/0xa0

See
https://lore.kernel.org/lkml/CAM6Wdxft33zLeeXHhmNX5jyJtfGTLiwkQSApc=10fqf+rQh9DA@mail.gmail.com/T/
for a discussion of the bug (easiest to start from the bottom). It seems that
on systems which allow more cpus than are initialized[1], rasdaemon will attempt
to poll non-existent cpus which causes a kernel oops. The fix for this
reportedly causes rasdaemon to segfault which will likely require a fix there
as well.

A workaround for systems experiencing the oops with linux-image-6.0.0-2 is to
disable rasdaemon.

[1] On my system, dmesg reports
smpboot: Allowing 32 CPUs, 16 hotplug CPUs
for a system with 8 cores/16 threads
#1023725#12
Date:
2026-06-25 08:10:48 UTC
From:
To:
How do we reproduce this situation?

This bug is 4 years old so presumably the kernel part was fixed long ago.  How
do I determine if rasdamon is fixed?
#1023725#21
Date:
2026-08-11 03:59:43 UTC
From:
To:
close 1023725
thanks

I'm not sure this was ever a rasdaemon bug.  Anyway I think everything is OK
now so closing.