After dozens and dozens of boots with the 3.2.0-14 and 3.2.0-15 kernels, here’s what I know.<\/p>\n
1. This *is* tied to wistron_btns as I reported. Without it, boot never fails (the way I initially reported, though I’ll redefine what ”fails” means further below).
\n2. With non-pae kernels, boot never fails.
\n3. With 3.2.0-14-pae, the boot always fails.
\n4. A cold boot with 3.2.0-15-pae never fails.
\n5. A re-boot with 3.2.0-15-pae after a *non-failing* boot never fails.
\n6. A re-boot of 3.2.0-15-pae, after a *failing* boot (of 3.2.0-14-pae for instance), is *almost* sure to fail. I’d give it a 10% chance of not failing.<\/p>\n
If you put it another way, this appears is pretty interesting:
\n1. You can ”break” 3.2.0-15-pae by booting 3.2.0-14-pae first.
\n2. You ”fix” a thus ”broken” 3.2.0-15-pae by booting a non-pae kernel.<\/p>\n
I suspect this brokenness is actually hidden in the hardware, in something (the wifi key perhaps?) controlled by wistron_btns. Booting 3.2.0-14-pae puts the controller(?) in a ”broken” state from which 3.2.0-15-pae can’t recover, but a non-pae kernel can. And though 3.2.0-15-pae can’t recover a ”broken” controller, it also cannot put it into that ”broken” state (which is a good turn of development).<\/p>\n
So now, about that ”fails” part.<\/p>\n
I discovered by accident that although the system appears to freeze in boots I referred to as ”fails”, it has in fact been brought down to *almost* complete halt, but *just* almost. If I’m patient enough to wait, it does actually boot into LDM, from where I can switch to another VT and log in… slooooooowly.<\/p>\n
Thus I was able to find out what’s going on that makes it so slow:<\/p>\n
jani@amilo:~$ head dmesg.fail
\nstron_btns: Unknown key code 10
\n[ 1011.554522] wistron_btns: Unknown key code 10
\n[ 1011.554722] wistron_btns: Unknown key code 10
\n[ 1011.554921] wistron_btns: Unknown key code 10
\n[ 1011.555120] wistron_btns: Unknown key code 10
\n[ 1011.555320] wistron_btns: Unknown key code 10
\n[ 1011.555518] wistron_btns: Unknown key code 10
\n[ 1011.555717] wistron_btns: Unknown key code 10
\n[ 1011.555916] wistron_btns: Unknown key code 10
\n[ 1011.556134] wistron_btns: Unknown key code 10
\njani@amilo:~$ grep wistron dmesg.fail | wc -l
\n2520<\/p>\n
Note that this is unrelated to pressing any actual physical buttons. It’ wistron_btns misbehaving under the conditions I described above.<\/p>\n","protected":false},"excerpt":{"rendered":"
If you put it another way, this appears is pretty interesting: 1. You can ”break” 3.2.0-15-pae by booting 3.2.0-14-pae first. 2. You ”fix” a thus ”broken” 3.2.0-15-pae by booting a non-pae kernel.<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8860],"tags":[27],"class_list":["post-2696","post","type-post","status-publish","format-standard","hentry","category-vianhallintajarjestelmat","tag-linux","sijainti-launchpad"],"_links":{"self":[{"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/posts\/2696","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/comments?post=2696"}],"version-history":[{"count":5,"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/posts\/2696\/revisions"}],"predecessor-version":[{"id":2701,"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/posts\/2696\/revisions\/2701"}],"wp:attachment":[{"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/media?parent=2696"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/categories?post=2696"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mummila.net\/kommentit\/wp-json\/wp\/v2\/tags?post=2696"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}