Re: [PATCH] fbcon: Make fbcon a built-time depency for fbdev

From: Steven Rostedt
Date: Wed Jun 28 2017 - 11:08:31 EST


On Wed, 28 Jun 2017 12:36:35 +0200
Daniel Vetter <daniel.vetter@xxxxxxxx> wrote:

> There's a bunch of folks who're trying to make printk less
> contended and faster, but there's a problem: printk uses the
> console_lock, and the console lock has become the BKL for all things
> fbdev/fbcon, which in turn pulled in half the drm subsystem under that
> lock. That's awkward.
>

I applied your patch and compiled it, and got this error while
installing modules:

DEPMOD 4.12.0-rc5-test+
depmod: ERROR: Found 11 modules in dependency cycles!
depmod: ERROR: Cycle detected: fbcon -> bitblit -> softcursor -> fb -> fbcon
depmod: ERROR: Cycle detected: softcursor -> fb -> fbcon_rotate -> fbcon_ccw -> softcursor
depmod: ERROR: Cycle detected: fb -> fbcon_rotate -> fbcon_ccw -> fb
depmod: ERROR: Cycle detected: softcursor -> fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> softcursor
depmod: ERROR: Cycle detected: fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fb
depmod: ERROR: Cycle detected: softcursor -> fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fbcon_cw -> softcursor
depmod: ERROR: Cycle detected: fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fbcon_cw -> fb
depmod: ERROR: Cycle detected: fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fbcon_cw -> fb
depmod: ERROR: Cycle detected: fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fbcon_cw -> tileblit -> fb
depmod: ERROR: Cycle detected: fbcon -> bitblit -> softcursor -> fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fbcon_cw -> tileblit -> fbdev
depmod: ERROR: Cycle detected: fb -> fbcon_rotate -> fbcon_ccw -> fbcon_ud -> fbcon_cw -> tileblit -> fb
/work/git/linux-trace.git/Makefile:1251: recipe for target '_modinst_post' failed


Config attached.

Oh, and I changed CONFIG_FB to be a module, which is probably where the
error happened.

-- Steve

Attachment: config
Description: Binary data