lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 23 Jul 2007 14:05:41 -0700 From: Andrew Morton <akpm@...ux-foundation.org> To: "Mike Frysinger" <vapier.adi@...il.com> Cc: "Robin Getz" <rgetz@...ckfin.uclinux.org>, linux-kernel@...r.kernel.org, "Greg Ungerer" <gerg@...pgear.com>, "Russell King" <rmk@....linux.org.uk>, "Paul Mundt" <lethal@...ux-sh.org>, "Tim Bird" <tim.bird@...sony.com>, bryan.wu@...log.com Subject: Re: early_printk accessing __log_buf On Mon, 23 Jul 2007 16:54:36 -0400 "Mike Frysinger" <vapier.adi@...il.com> wrote: > On 7/23/07, Andrew Morton <akpm@...ux-foundation.org> wrote: > > On Mon, 23 Jul 2007 14:19:12 -0400 > > Robin Getz <rgetz@...ckfin.uclinux.org> wrote: > > > > > On Sun 22 Jul 2007 19:50, Mike Frysinger pondered: > > > > > > > > i think the attached two functions account for what Robin and Andrew > > > > were thinking ... > > > > > > A note about why/when grab_lock would be set to zero (pre-kernel init, or > > > OOPs) might be nice. > > > > Definitely. > > > > The pre-kernel init shouldn't be an issue: logbuf_lock is initialised at > > compile time. > > > > At oops time we could possibly use oops_in_progress to work out whether to > > avoid taking the lock. That's not terribly nice, but nor is it nice for > > callers to know about printk internals. > > maybe, but for early debug users (the reason we wanted this > originally), it wouldnt be an oops in progress ... but i guess we can > just as easily set oops_in_progress to 1 in our code before calling > this function to keep from having to worry over locks from being > doubly grabbed. I don't immediately see how logbuf_lock could be doubly grabbed. Only if you're calling this from hard irq context? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists