Re: random insta-reboots on AMD Phenom II

From: Adam Borowski
Date: Sun Oct 01 2017 - 09:07:08 EST


On Sat, Sep 30, 2017 at 01:53:02PM +0200, Borislav Petkov wrote:
> On Sat, Sep 30, 2017 at 01:29:03PM +0200, Adam Borowski wrote:
> > On Sat, Sep 30, 2017 at 01:11:37PM +0200, Borislav Petkov wrote:
> > > On Sat, Sep 30, 2017 at 04:05:16AM +0200, Adam Borowski wrote:

> Boot into -rc2+ and do as root:
>
> # wrmsr -a 0xc0010015 0x1000018

Seems to help, thus it's indeed this issue. I failed to mention that "once
per day" meant a day of regular use, of which heavy loads were only a tiny
fraction. I've applied this register setting, then kept the machine busy
(mostly with randconfig kernel builds) for a day, no explosions yet -- so
there's a good chance the problem would have triggered.

> If the issue gets fixed then Mr. Luto better revert the new lazy TLB
> flushing fun'n'games for 4.14 before it is too late and that kernel
> releases b0rked.

I have no clue about these matters so I'll leave it to you guys. But, as
the other report I see gives different effects (frequent segfaults vs rare
insta-reboots), you do want to include my machine in testing.

Thanks for the workaround!

Meow!
--
âââââââ We domesticated dogs 36000 years ago; together we chased
âââââââ animals, hung out and licked or scratched our private parts.
âââââââ Cats domesticated us 9500 years ago, and immediately we got
âââââââ agriculture, towns then cities. -- whitroth on /.