Weird temporary workaround for kernel 4.15.0-24 boot issue

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catweazel
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Weird temporary workaround for kernel 4.15.0-24 boot issue

Post by catweazel » Wed Jul 04, 2018 5:43 pm

https://ubuntuforums.org/showthread.php ... 451&page=2

"move the mouse while it is booting, just swing it side to side or circle as long as it is moving it'll boot right up."

Greg Kroah-Hartman strikes again. The last time we had a LTS kernel debacle, Kroah-Hartman blamed nvidia. I wonder who he'll blame for his latest mess.
¡uʍop ǝpısdn sı buıɥʇʎɹǝʌǝ os ɐıןɐɹʇsnɐ ɯoɹɟ ɯ,ı

JeremyB
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Re: Weird temporary workaround for kernel 4.15.0-24 boot issue

Post by JeremyB » Wed Jul 04, 2018 5:48 pm

Linus
This was only done 6 days ago https://git.kernel.org/pub/scm/linux/ke ... a661f01144
Most of the problem commits are from April

What post # has the strange fix? Page 2 doesn't work for me as I have my posts per page set at 75

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catweazel
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Re: Weird temporary workaround for kernel 4.15.0-24 boot issue

Post by catweazel » Wed Jul 04, 2018 5:54 pm

JeremyB wrote:
Wed Jul 04, 2018 5:48 pm
Linus
This was only done 6 days ago https://git.kernel.org/pub/scm/linux/ke ... a661f01144
Most of the problem commits are from April

What post # has the strange fix? Page 2 doesn't work for me as I have my posts per page set at 75
https://ubuntuforums.org/showthread.php ... st13780509

#12
¡uʍop ǝpısdn sı buıɥʇʎɹǝʌǝ os ɐıןɐɹʇsnɐ ɯoɹɟ ɯ,ı

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catweazel
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Re: Weird temporary workaround for kernel 4.15.0-24 boot issue

Post by catweazel » Wed Jul 04, 2018 5:55 pm

JeremyB wrote:
Wed Jul 04, 2018 5:48 pm
This was only done 6 days ago https://git.kernel.org/pub/scm/linux/ke ... a661f01144
I like how he doesn't pull punches...

Code: Select all

The poll() changes were not well thought out, and completely unexplained. They also caused a huge
performance regression, because "->poll()" was no longer a trivial file operation that just called down to
the underlying file operations, but instead did at least two indirect calls. Indirect calls are sadly slow now
with the Spectre mitigation, but the performance problem could at least be largely mitigated by changing
the "->get_poll_head()" operation to just have a per-file-descriptor pointer to the poll head instead. That
gets rid of one of the new indirections. But that doesn't fix the new complexity that is completely
unwarranted for the regular case. The (undocumented) reason for the poll() changes was some alleged AIO
poll race fixing, but we don't make the common case slower and more complex for some uncommon special
case, so this all really needs way more explanations and most likely a fundamental redesign. 
¡uʍop ǝpısdn sı buıɥʇʎɹǝʌǝ os ɐıןɐɹʇsnɐ ɯoɹɟ ɯ,ı

Hoser Rob
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Re: Weird temporary workaround for kernel 4.15.0-24 boot issue

Post by Hoser Rob » Thu Jul 05, 2018 9:51 am

catweazel wrote:
Wed Jul 04, 2018 5:43 pm
https://ubuntuforums.org/showthread.php ... 451&page=2

"move the mouse while it is booting, just swing it side to side or circle as long as it is moving it'll boot right up."

Greg Kroah-Hartman strikes again. The last time we had a LTS kernel debacle, Kroah-Hartman blamed nvidia. I wonder who he'll blame for his latest mess.
Buck passing is one of the biggest issues in FOSS software development. I think that's why there are so many ancient unresolved bugs in Linux, and not just minor ones. Like the one that lets xorg grab exclusive input control, so sometimes if you crash not even alt-sysreq REISUB will work.

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