Bug 104921
| Summary: | BUG: unable to handle kernel NULL pointer dereference at (null) | ||
|---|---|---|---|
| Product: | IO/Storage | Reporter: | Curtis Lee Bolin (CurtisLeeBolin) |
| Component: | MD | Assignee: | io_md |
| Status: | RESOLVED PATCH_ALREADY_AVAILABLE | ||
| Severity: | normal | CC: | neilb |
| Priority: | P1 | ||
| Hardware: | x86-64 | ||
| OS: | Linux | ||
| Kernel Version: | Linux version 4.1.6-1-ARCH (builduser@tobias) (gcc version 5.2.0 (GCC) ) #1 SMP PREEMPT Mon Aug 17 08:52:28 CEST 2015 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
| Attachments: |
journal of error
Commit: 49895bcc7e56 Commit: 2d5b569b665e |
||
This is almost certainly fixed by
Commit: 49895bcc7e56 ("md/raid5: don't let shrink_slab shrink too far.")
I had hoped this would be in 4.1-stable by now, but it isn't. I have just sent to to stable@vger.kernel.org so it should be in 4.1.9.
If you are going to apply it, it would be good to apply
Commit: 2d5b569b665e ("md/raid5: avoid races when changing cache size.")
first. It has a simple easy to resolve conflict.
Created attachment 188251 [details]
Commit: 49895bcc7e56
Created attachment 188261 [details]
Commit: 2d5b569b665e
Neil Brown, thank you for your fast reply. I was getting worried because every time the qemu VM would tax the MD RAID5 hard, my server would lock up. I use Arch Linux so I create patches from your Commits, added them to the PKGBUILD, rebuilt the linux package, installed, and rebooted. I have tried very hard now for over 2 hours to get it to lock up again. I can confirm this solved my problem. I attached the patches just to confirm which ones I tried. Thanks again, Neil. Yes, those are the correct patches. Thanks for the confirmation that they fix the problem. |
Created attachment 188201 [details] journal of error Sep 23 18:44:12 sv kernel: BUG: unable to handle kernel NULL pointer dereference at (null) Sep 23 18:44:12 sv kernel: IP: [<ffffffffa07d8b91>] get_free_stripe+0x31/0xf0 [raid456]