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Sometimes I can't boot my laptop - it gets stuck here:

enter image description here

Then I have to do a hard-reset and it's fine. I checked the boot logs and this is what I think it's causing it (nevermind the timestamp inconsistencies):

[38.377595] BUG: unable to handle kernel NULL pointer dereference at           (null)
[38.377821] IP: [<ffffffffa01f6d7b>] r600_pcie_gart_tlb_flush+0xeb/0x110 [radeon]
[38.378065] PGD 121491067 PUD 121492067 PMD 0 
[38.378214] Oops: 0000 [#1] SMP

Here is the full log.

I found the patches but I have no idea about which to use and how.

share|improve this question
Possible duplicate? – Tom Brossman Sep 2 '12 at 7:38
No, user in that thread asked only about how to apply patch - what I essentially want too; but I also need some help about deciding which patch should I use or if I should just do a dist-upgrade to get a new kernel? – Primož Kralj Sep 2 '12 at 7:41
You are better off upgrading your kernel. Because you don't exactly know what bug hit you and hence, can't choose the most appropriate patch. Moreover, it is highly likely the latest kernel should have patched up your bug already. – jokerdino Sep 2 '12 at 8:42
up vote 1 down vote accepted

What I did:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

It essentially upgraded the kernel without making my hands dirty with patching the kernel myself.

I am not sure if it will help with my boot fail issue - have to boot a few times to see but I will report back. As far as the question is concerned, it is resolved.

share|improve this answer
Hopefully it's that simple! You can always post a new question later if you have more clues or data. – Tom Brossman Sep 2 '12 at 12:17
So far 5 boots and 0 problems :) Hope It stays this way. – Primož Kralj Sep 2 '12 at 14:07
I can confirm this fixes the bug. – Primož Kralj Sep 23 '12 at 7:21

The bug was fixed by upgrading the kernel, but this doesn't answer the opening question and is unsatisfying for everyone arriving here hoping for an answer.

So, how does one, generally, patch a kernel bug when patch files are available?

share|improve this answer
Did you follow the link from the first comment after the opening question? Also, your answer is a comment, not an answer, so it is not really in the right place. – Marty Fried Oct 11 '12 at 23:33

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