From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Fleming Subject: Re: [PATCH V2] earlyprintk=efi,keep fix Date: Fri, 2 May 2014 14:00:31 +0100 Message-ID: <20140502130031.GT26088@console-pimps.org> References: <20140501131548.GA15258@darkstar.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20140501131548.GA15258-4/PLUo9XfK/1wF9wiOj0lkEOCMrvLtNR@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Dave Young Cc: matt.fleming-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-efi@vger.kernel.org On Thu, 01 May, at 09:15:48PM, Dave Young wrote: > > earlyprintk=efi,keep will cause kernel hangs while freeing initmem like below: > [ 2.826089] VFS: Mounted root (ext4 filesystem) readonly on device 254:2. > [ 2.846592] devtmpfs: mounted > [ 2.856974] Freeing unused kernel memory: 880K (ffffffff817d4000 - ffffffff818b0000) > > It is caused by efi earlyprintk use __init function which will be freed later. > Such as early_efi_write is marked as __init, also it will use early_ioremap > which is init function as well. > > To fix this issue, I added early initcall early_efi_map_fb which maps the whole > efi fb for later use. OTOH, adding a wrapper function early_efi_map which calls > early_ioremap before ioremap is available. > > With this patch applied efi boot ok with earlyprintk=efi,keep console=efi > > Signed-off-by: Dave Young > --- > arch/x86/platform/efi/early_printk.c | 83 ++++++++++++++++++++++++++--------- > 1 file changed, 64 insertions(+), 19 deletions(-) Thanks Dave, applied! -- Matt Fleming, Intel Open Source Technology Center