Gentoo Archives: gentoo-user

From: Greg Turner <gmt@×××××.us>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Re: Kernel boot messages are no longer displayed
Date: Sun, 25 May 2014 08:02:21
Message-Id: CA+VB3NRAmYw8_WB_OS+d9VXOTnQgU_6mdVuXrGCpVb5ZYGrLjg@mail.gmail.com
In Reply to: Re: [gentoo-user] Re: Kernel boot messages are no longer displayed by Hilco Wijbenga
1 The essence of your problem is: you need a working console during your boot
2 sequence if you want to see anything. For an X86 'puter the main two ways
3 to get that are: the VGA console, and the framebuffer console
4 (CONFIG_VGA_CONSOLE, almost always works in a pinch unless you boot from
5 EFI, in which case it probably doesn't work at all).
6
7 A working framebuffer console needs a working framebuffer. The glue that
8 says (as best I understand it): "hey, Mr. kernel, please don't just leave
9 that framebuffer of mine just lying around doing nothing, let's use it as a
10 console" is CONFIG_FRAMEBUFFER_CONSOLE.
11
12 Furthermore, CONFIG_EARLY_PRINTK is required if you want the really early
13 junk to whiz by illegibly at the beginning of your boot sequence (the stuff
14 that looks about like the output of "dmesg|head -n 500")
15
16 If you compiled your framebuffer as a module, it also won't load until that
17 module does. Which means, either until udev starts (and successfully loads
18 the module) or until it gets loaded by some other means, i.e., by script
19 code in an initrd/initramfs.
20
21 The's a migration, in linuxville, underway now, from the old-school
22 "userspace modesetting" paradigm (where graphic card configuration sorta
23 worked like Windows 95: the "drivers" were hyper-privileged user-land
24 programs running amok) to the newer, shinier "kernel modesetting" paradigm,
25 which finally brings linux, let's say, into a "Windows NT 3.5" sort-of
26 epoch (i.e.: working drivers, at least, finally, in the kernel, where they
27 belong -- but, God help you, if you start hot-plugging stuff or want to use
28 suspend, that stuff all broke). There has been some pain and upheaval.
29 Recipes that used to work have been breaking and you just have to read
30 your logs and some wikis and figure it out, sometimes, the old fashioned
31 way.
32
33 If you run radeon, well, read the wiki, most of the advice in there is
34 correct and necessary to get a working accelerated system these days --
35 disabling KMS will break your xorg and your framebuffer entirely! also be
36 /sure/ CONFIG_FB_RADEON and CONFIG_DRM_RADEON_UMS are both OFF (that's the
37 /opposite/ of on!! I mean it!!!) and CONFIG_DRM_RADEON is on (preferably
38 compiled into the kernel). Finally: if you you are using fglrx... well,
39 frankly, your drivers are a sinking ship, bail now while you are still
40 breathing. I'm not up to speed on the latest nvidia trouble but, read the
41 wiki is probably the best advice.
42
43
44 On Sat, May 24, 2014 at 8:19 PM, Hilco Wijbenga <hilco.wijbenga@×××××.com>wrote:
45
46 > On 24 May 2014 16:53, walt <w41ter@×××××.com> wrote:
47 > > On 05/24/2014 01:20 PM, Hilco Wijbenga wrote:
48 > >> Since kernel 3.12.13 (3.12.13-gentoo), the kernel boot messages have
49 > >> disappeared, i.e. they are no longer displayed at boot time. All I get
50 > >> is a line like "Loading kernel 3.12.13". (I just upgraded to
51 > >> 3.12.20-gentoo, so now it's something like "Loading kernel 3.12.20".)
52 > >>
53 > >> I have no idea why. I checked my grub config and it does not add a
54 > >> "quiet" argument. I see nothing in /etc/rc.conf about quiet (or
55 > >> verbose). And X86_VERBOSE_BOOTUP is set to 'y'. I also looked for
56 > >> "quiet", "boot", and "messages" (while running "make xconfig") and
57 > >> nothing untoward showed up.
58 > >>
59 > >> How do I get back to a normal and sane boot process?
60 > >
61 > > What is the next thing you see after "Loading kernel 3.12.20" ?
62 >
63 > Nothing. There is a pause of a dozen seconds or so and then the login
64 > panel appears.
65 >
66 > By the way, I checked again and it says "Loading Linux 3.12.20-gentoo
67 > ..." (just to be complete and precise).
68 >
69 > > What was the last kernel that booted normally? Does it still boot
70 > > normally?
71 >
72 > I don't quite remember. :-( Probably whatever kernel came before
73 > 3.12.13 but I don't have any leftover configs or anything like that. I
74 > ran the sys-kernel/aufs-sources (to be able to use Docker) so it might
75 > have been one of those but I doubt it.
76 >
77 > > The kernel config files for each kernel are installed as
78 > > /boot/config-3.12.nn so you can compare them to see what changed.
79 >
80 > Well, not by default... :-) In any case, I have deleted it all. It
81 > didn't seem a difficult thing to fix and whenever I had logged in
82 > other stuff happened that made me forget about the boot messages. :-)
83 > It's just today I decided to google for it. Surprisingly, nobody is
84 > complaining about this so it must be something specific to my
85 > environment. I just have no clue what. I certainly did nothing (on
86 > purpose) to get rid of boot messages.
87 >
88 >