| 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: Thu, 31 Jul 2014 15:45:40 -0700 From: Andrew Morton <akpm@...ux-foundation.org> To: Chintan Pandya <cpandya@...eaurora.org> Cc: David Rientjes <rientjes@...gle.com>, linux-kernel@...r.kernel.org, linux-mm@...ck.org Subject: Re: [PATCH v2] mm: BUG when __kmap_atomic_idx equals KM_TYPE_NR On Thu, 31 Jul 2014 14:58:58 +0530 Chintan Pandya <cpandya@...eaurora.org> wrote: > > > > I think Andrew's comment earlier was referring to the changelog only and > > not the patch, which looked correct. > > I think Andrew asked for a BUG case details also to justify the > overhead. But we have never encountered that BUG case. Present patch is > only logical fix to the code. However, in the fast path, if such > overhead is allowed, I can move BUG_ON out of any debug configs. > Otherwise, as per Andrew's suggestion, I will convert DEBUG_HIGHMEM into > DEBUG_VM which is used more frequently. The v1 patch added a small amount of overhead to kmap_atomic() for what is evidently a very small benefit. Yes, I suggest we remove CONFIG_DEBUG_HIGHMEM from the kernel entirely and switch all CONFIG_DEBUG_HIGHMEM sites to use CONFIG_DEBUG_VM. That way the BUG_ON which you believe is useful will be tested by more people more often. -- 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