From: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>
To: jim.cromie@gmail.com
Cc: kernelnewbies <kernelnewbies@kernelnewbies.org>
Subject: Re: CONFIG_KDB_KEYBOARD
Date: Mon, 03 Aug 2020 13:48:41 -0400 [thread overview]
Message-ID: <27268.1596476921@turing-police> (raw)
In-Reply-To: <CAJfuBxwJ_bFzs6rTFbD5fovvsSn7LyuJPe=p5PkqJadGW3xJog@mail.gmail.com>
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On Mon, 03 Aug 2020 11:30:05 -0600, jim.cromie@gmail.com said:
> I notice this excludes USB keyboard.
>
> does this mean it doesnt work early enough to be useful for early panics etc?
Very early panics and hangs are always a royal pain to deal with. There's no
really good way to deal with it, because let's face it - if the operating
system hasn't gotten its act together yet, it's going to have a hard time
talking to you unless you can run it in a virtual machine or similar that has
the tooling to allow you to usefully explore the memory entrails.
> what does it mean for a panic right after starting 2nd CPUs ?
> [ 0.416908] kthreadd invoked oom-killer: gfp_mask=0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GF
> gfp_mask=0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), order=0, oom_score_adj=0
> [ 0.417551] CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.8.0-rc7-00023-gede6954dc460-dirty #101
> [ 0.418541] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014
Hitting the OOM killer on PID 2 in QEMU sounds suspiciously like you started
QEMU and specified an insanely small memory space for the image.
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next prev parent reply other threads:[~2020-08-03 17:49 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-03 17:30 CONFIG_KDB_KEYBOARD jim.cromie
2020-08-03 17:48 ` Valdis Klētnieks [this message]
2020-08-03 20:30 ` CONFIG_KDB_KEYBOARD jim.cromie
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