From mboxrd@z Thu Jan 1 00:00:00 1970 From: David VomLehn Subject: Re: [PATCH] Wait for console to become available, v2 Date: Sun, 19 Apr 2009 16:17:11 -0700 Message-ID: <49EBB0F7.3050606@cisco.com> References: <20090416190837.GA26734@cuplxvomd02.corp.sa.net> <874owlqcce.fsf@basil.nowhere.org> <49EB5008.1090000@cisco.com> <20090419163923.GS14687@one.firstfloor.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090419163923.GS14687-qrUzlfsMFqo/4alezvVtWx2eb7JE58TQ@public.gmane.org> DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; l=1208; t=1240183037; x=1241047037; c=relaxed/simple; s=sjdkim1004; h=Content-Type:From:Subject:Content-Transfer-Encoding:MIME-Version; d=cisco.com; i=dvomlehn-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org; z=From:=20David=20VomLehn=20 |Subject:=20Re=3A=20[PATCH]=20Wait=20for=20console=20to=20b ecome=20available,=20v2 |Sender:=20; bh=LKgucMAKZNb/KjIX6jL3H/39joAa061RHFRgL4+X9T0=; b=hMBVZhwpmKJq1oJnGls+k29c56z11w1IluS4aTozLcu+xZQT6EYSrJhPuY FzRg3dUpc1jJNheOvSzXY9olydqhvadtQsHLud+K1b+lKPhaxcYQiYHg2JbS LT/4ziPZbb9dw7ciW01r0LDQCxmwNgJeG+pVypc8r78q2AYhN7S0s=; Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Andi Kleen Cc: Linux Kernel Mailing List , Andrew Morton , Linux Embedded Mailing List , Linux USB Mailing List Andi Kleen wrote: > On Sun, Apr 19, 2009 at 09:23:36AM -0700, David VomLehn wrote: >> Andi Kleen wrote: >>> VomLehn writes: ... >>> Also a setting to panic in this case might be useful, normally a system >>> without console is not very useful and needs to be rebooted anyways. >> Umm, those of us in the embedded space have the, perhaps misguided, >> notion that our systems are quite useful without consoles... > > That seems more like a special case that shouldn't be default? I have to disagree. Panicing because you can't open /dev/console is likely to mean that you get no output at all and so no chance to see a message explaining why the open failed. If the open failure is all that happened, the rest of the system may very well come up normally. You would then be able to look at the kernel log and diagnose the issue. In any case, the purpose of this patch is fix USB consoles to work as they did before parallelized startup. This involves addressing a race condition that, theoretically, always existed but which previously hadn't been a problem. Changing the behavior when init_post() can't open /dev/console seems out of scope. > -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html